Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * heapam.c
4 : : * heap access method code
5 : : *
6 : : * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
7 : : * Portions Copyright (c) 1994, Regents of the University of California
8 : : *
9 : : *
10 : : * IDENTIFICATION
11 : : * src/backend/access/heap/heapam.c
12 : : *
13 : : *
14 : : * INTERFACE ROUTINES
15 : : * heap_beginscan - begin relation scan
16 : : * heap_rescan - restart a relation scan
17 : : * heap_endscan - end relation scan
18 : : * heap_getnext - retrieve next tuple in scan
19 : : * heap_fetch - retrieve tuple with given tid
20 : : * heap_insert - insert tuple into a relation
21 : : * heap_multi_insert - insert multiple tuples into a relation
22 : : * heap_delete - delete a tuple from a relation
23 : : * heap_update - replace a tuple in a relation with another tuple
24 : : *
25 : : * NOTES
26 : : * This file contains the heap_ routines which implement
27 : : * the POSTGRES heap access method used for all POSTGRES
28 : : * relations.
29 : : *
30 : : *-------------------------------------------------------------------------
31 : : */
32 : : #include "postgres.h"
33 : :
34 : : #include "access/heapam.h"
35 : : #include "access/heaptoast.h"
36 : : #include "access/hio.h"
37 : : #include "access/multixact.h"
38 : : #include "access/subtrans.h"
39 : : #include "access/syncscan.h"
40 : : #include "access/valid.h"
41 : : #include "access/visibilitymap.h"
42 : : #include "access/xloginsert.h"
43 : : #include "catalog/pg_database.h"
44 : : #include "catalog/pg_database_d.h"
45 : : #include "commands/vacuum.h"
46 : : #include "pgstat.h"
47 : : #include "port/pg_bitutils.h"
48 : : #include "storage/lmgr.h"
49 : : #include "storage/predicate.h"
50 : : #include "storage/procarray.h"
51 : : #include "utils/datum.h"
52 : : #include "utils/injection_point.h"
53 : : #include "utils/inval.h"
54 : : #include "utils/spccache.h"
55 : : #include "utils/syscache.h"
56 : :
57 : :
58 : : static HeapTuple heap_prepare_insert(Relation relation, HeapTuple tup,
59 : : TransactionId xid, CommandId cid, int options);
60 : : static XLogRecPtr log_heap_update(Relation reln, Buffer oldbuf,
61 : : Buffer newbuf, HeapTuple oldtup,
62 : : HeapTuple newtup, HeapTuple old_key_tuple,
63 : : bool all_visible_cleared, bool new_all_visible_cleared);
64 : : #ifdef USE_ASSERT_CHECKING
65 : : static void check_lock_if_inplace_updateable_rel(Relation relation,
66 : : ItemPointer otid,
67 : : HeapTuple newtup);
68 : : static void check_inplace_rel_lock(HeapTuple oldtup);
69 : : #endif
70 : : static Bitmapset *HeapDetermineColumnsInfo(Relation relation,
71 : : Bitmapset *interesting_cols,
72 : : Bitmapset *external_cols,
73 : : HeapTuple oldtup, HeapTuple newtup,
74 : : bool *has_external);
75 : : static bool heap_acquire_tuplock(Relation relation, ItemPointer tid,
76 : : LockTupleMode mode, LockWaitPolicy wait_policy,
77 : : bool *have_tuple_lock);
78 : : static inline BlockNumber heapgettup_advance_block(HeapScanDesc scan,
79 : : BlockNumber block,
80 : : ScanDirection dir);
81 : : static pg_noinline BlockNumber heapgettup_initial_block(HeapScanDesc scan,
82 : : ScanDirection dir);
83 : : static void compute_new_xmax_infomask(TransactionId xmax, uint16 old_infomask,
84 : : uint16 old_infomask2, TransactionId add_to_xmax,
85 : : LockTupleMode mode, bool is_update,
86 : : TransactionId *result_xmax, uint16 *result_infomask,
87 : : uint16 *result_infomask2);
88 : : static TM_Result heap_lock_updated_tuple(Relation rel, HeapTuple tuple,
89 : : ItemPointer ctid, TransactionId xid,
90 : : LockTupleMode mode);
91 : : static void GetMultiXactIdHintBits(MultiXactId multi, uint16 *new_infomask,
92 : : uint16 *new_infomask2);
93 : : static TransactionId MultiXactIdGetUpdateXid(TransactionId xmax,
94 : : uint16 t_infomask);
95 : : static bool DoesMultiXactIdConflict(MultiXactId multi, uint16 infomask,
96 : : LockTupleMode lockmode, bool *current_is_member);
97 : : static void MultiXactIdWait(MultiXactId multi, MultiXactStatus status, uint16 infomask,
98 : : Relation rel, ItemPointer ctid, XLTW_Oper oper,
99 : : int *remaining);
100 : : static bool ConditionalMultiXactIdWait(MultiXactId multi, MultiXactStatus status,
101 : : uint16 infomask, Relation rel, int *remaining,
102 : : bool logLockFailure);
103 : : static void index_delete_sort(TM_IndexDeleteOp *delstate);
104 : : static int bottomup_sort_and_shrink(TM_IndexDeleteOp *delstate);
105 : : static XLogRecPtr log_heap_new_cid(Relation relation, HeapTuple tup);
106 : : static HeapTuple ExtractReplicaIdentity(Relation relation, HeapTuple tp, bool key_required,
107 : : bool *copy);
108 : :
109 : :
110 : : /*
111 : : * Each tuple lock mode has a corresponding heavyweight lock, and one or two
112 : : * corresponding MultiXactStatuses (one to merely lock tuples, another one to
113 : : * update them). This table (and the macros below) helps us determine the
114 : : * heavyweight lock mode and MultiXactStatus values to use for any particular
115 : : * tuple lock strength.
116 : : *
117 : : * These interact with InplaceUpdateTupleLock, an alias for ExclusiveLock.
118 : : *
119 : : * Don't look at lockstatus/updstatus directly! Use get_mxact_status_for_lock
120 : : * instead.
121 : : */
122 : : static const struct
123 : : {
124 : : LOCKMODE hwlock;
125 : : int lockstatus;
126 : : int updstatus;
127 : : }
128 : :
129 : : tupleLockExtraInfo[MaxLockTupleMode + 1] =
130 : : {
131 : : { /* LockTupleKeyShare */
132 : : AccessShareLock,
133 : : MultiXactStatusForKeyShare,
134 : : -1 /* KeyShare does not allow updating tuples */
135 : : },
136 : : { /* LockTupleShare */
137 : : RowShareLock,
138 : : MultiXactStatusForShare,
139 : : -1 /* Share does not allow updating tuples */
140 : : },
141 : : { /* LockTupleNoKeyExclusive */
142 : : ExclusiveLock,
143 : : MultiXactStatusForNoKeyUpdate,
144 : : MultiXactStatusNoKeyUpdate
145 : : },
146 : : { /* LockTupleExclusive */
147 : : AccessExclusiveLock,
148 : : MultiXactStatusForUpdate,
149 : : MultiXactStatusUpdate
150 : : }
151 : : };
152 : :
153 : : /* Get the LOCKMODE for a given MultiXactStatus */
154 : : #define LOCKMODE_from_mxstatus(status) \
155 : : (tupleLockExtraInfo[TUPLOCK_from_mxstatus((status))].hwlock)
156 : :
157 : : /*
158 : : * Acquire heavyweight locks on tuples, using a LockTupleMode strength value.
159 : : * This is more readable than having every caller translate it to lock.h's
160 : : * LOCKMODE.
161 : : */
162 : : #define LockTupleTuplock(rel, tup, mode) \
163 : : LockTuple((rel), (tup), tupleLockExtraInfo[mode].hwlock)
164 : : #define UnlockTupleTuplock(rel, tup, mode) \
165 : : UnlockTuple((rel), (tup), tupleLockExtraInfo[mode].hwlock)
166 : : #define ConditionalLockTupleTuplock(rel, tup, mode, log) \
167 : : ConditionalLockTuple((rel), (tup), tupleLockExtraInfo[mode].hwlock, (log))
168 : :
169 : : #ifdef USE_PREFETCH
170 : : /*
171 : : * heap_index_delete_tuples and index_delete_prefetch_buffer use this
172 : : * structure to coordinate prefetching activity
173 : : */
174 : : typedef struct
175 : : {
176 : : BlockNumber cur_hblkno;
177 : : int next_item;
178 : : int ndeltids;
179 : : TM_IndexDelete *deltids;
180 : : } IndexDeletePrefetchState;
181 : : #endif
182 : :
183 : : /* heap_index_delete_tuples bottom-up index deletion costing constants */
184 : : #define BOTTOMUP_MAX_NBLOCKS 6
185 : : #define BOTTOMUP_TOLERANCE_NBLOCKS 3
186 : :
187 : : /*
188 : : * heap_index_delete_tuples uses this when determining which heap blocks it
189 : : * must visit to help its bottom-up index deletion caller
190 : : */
191 : : typedef struct IndexDeleteCounts
192 : : {
193 : : int16 npromisingtids; /* Number of "promising" TIDs in group */
194 : : int16 ntids; /* Number of TIDs in group */
195 : : int16 ifirsttid; /* Offset to group's first deltid */
196 : : } IndexDeleteCounts;
197 : :
198 : : /*
199 : : * This table maps tuple lock strength values for each particular
200 : : * MultiXactStatus value.
201 : : */
202 : : static const int MultiXactStatusLock[MaxMultiXactStatus + 1] =
203 : : {
204 : : LockTupleKeyShare, /* ForKeyShare */
205 : : LockTupleShare, /* ForShare */
206 : : LockTupleNoKeyExclusive, /* ForNoKeyUpdate */
207 : : LockTupleExclusive, /* ForUpdate */
208 : : LockTupleNoKeyExclusive, /* NoKeyUpdate */
209 : : LockTupleExclusive /* Update */
210 : : };
211 : :
212 : : /* Get the LockTupleMode for a given MultiXactStatus */
213 : : #define TUPLOCK_from_mxstatus(status) \
214 : : (MultiXactStatusLock[(status)])
215 : :
216 : : /*
217 : : * Check that we have a valid snapshot if we might need TOAST access.
218 : : */
219 : : static inline void
151 nathan@postgresql.or 220 :CBC 10498136 : AssertHasSnapshotForToast(Relation rel)
221 : : {
222 : : #ifdef USE_ASSERT_CHECKING
223 : :
224 : : /* bootstrap mode in particular breaks this rule */
225 [ + + ]: 10498136 : if (!IsNormalProcessingMode())
226 : 585600 : return;
227 : :
228 : : /* if the relation doesn't have a TOAST table, we are good */
229 [ + + ]: 9912536 : if (!OidIsValid(rel->rd_rel->reltoastrelid))
230 : 5117163 : return;
231 : :
232 [ - + ]: 4795373 : Assert(HaveRegisteredOrActiveSnapshot());
233 : :
234 : : #endif /* USE_ASSERT_CHECKING */
235 : : }
236 : :
237 : : /* ----------------------------------------------------------------
238 : : * heap support routines
239 : : * ----------------------------------------------------------------
240 : : */
241 : :
242 : : /*
243 : : * Streaming read API callback for parallel sequential scans. Returns the next
244 : : * block the caller wants from the read stream or InvalidBlockNumber when done.
245 : : */
246 : : static BlockNumber
568 tmunro@postgresql.or 247 : 100898 : heap_scan_stream_read_next_parallel(ReadStream *stream,
248 : : void *callback_private_data,
249 : : void *per_buffer_data)
250 : : {
251 : 100898 : HeapScanDesc scan = (HeapScanDesc) callback_private_data;
252 : :
253 [ - + ]: 100898 : Assert(ScanDirectionIsForward(scan->rs_dir));
254 [ - + ]: 100898 : Assert(scan->rs_base.rs_parallel);
255 : :
256 [ + + ]: 100898 : if (unlikely(!scan->rs_inited))
257 : : {
258 : : /* parallel scan */
259 : 1569 : table_block_parallelscan_startblock_init(scan->rs_base.rs_rd,
260 : 1569 : scan->rs_parallelworkerdata,
261 : 1569 : (ParallelBlockTableScanDesc) scan->rs_base.rs_parallel);
262 : :
263 : : /* may return InvalidBlockNumber if there are no more blocks */
264 : 3138 : scan->rs_prefetch_block = table_block_parallelscan_nextpage(scan->rs_base.rs_rd,
265 : 1569 : scan->rs_parallelworkerdata,
266 : 1569 : (ParallelBlockTableScanDesc) scan->rs_base.rs_parallel);
267 : 1569 : scan->rs_inited = true;
268 : : }
269 : : else
270 : : {
271 : 99329 : scan->rs_prefetch_block = table_block_parallelscan_nextpage(scan->rs_base.rs_rd,
272 : 99329 : scan->rs_parallelworkerdata, (ParallelBlockTableScanDesc)
273 : 99329 : scan->rs_base.rs_parallel);
274 : : }
275 : :
276 : 100898 : return scan->rs_prefetch_block;
277 : : }
278 : :
279 : : /*
280 : : * Streaming read API callback for serial sequential and TID range scans.
281 : : * Returns the next block the caller wants from the read stream or
282 : : * InvalidBlockNumber when done.
283 : : */
284 : : static BlockNumber
285 : 3492394 : heap_scan_stream_read_next_serial(ReadStream *stream,
286 : : void *callback_private_data,
287 : : void *per_buffer_data)
288 : : {
289 : 3492394 : HeapScanDesc scan = (HeapScanDesc) callback_private_data;
290 : :
291 [ + + ]: 3492394 : if (unlikely(!scan->rs_inited))
292 : : {
293 : 963452 : scan->rs_prefetch_block = heapgettup_initial_block(scan, scan->rs_dir);
294 : 963452 : scan->rs_inited = true;
295 : : }
296 : : else
297 : 2528942 : scan->rs_prefetch_block = heapgettup_advance_block(scan,
298 : : scan->rs_prefetch_block,
299 : : scan->rs_dir);
300 : :
301 : 3492394 : return scan->rs_prefetch_block;
302 : : }
303 : :
304 : : /*
305 : : * Read stream API callback for bitmap heap scans.
306 : : * Returns the next block the caller wants from the read stream or
307 : : * InvalidBlockNumber when done.
308 : : */
309 : : static BlockNumber
227 melanieplageman@gmai 310 : 208876 : bitmapheap_stream_read_next(ReadStream *pgsr, void *private_data,
311 : : void *per_buffer_data)
312 : : {
313 : 208876 : TBMIterateResult *tbmres = per_buffer_data;
314 : 208876 : BitmapHeapScanDesc bscan = (BitmapHeapScanDesc) private_data;
315 : 208876 : HeapScanDesc hscan = (HeapScanDesc) bscan;
316 : 208876 : TableScanDesc sscan = &hscan->rs_base;
317 : :
318 : : for (;;)
319 : : {
320 [ - + ]: 208876 : CHECK_FOR_INTERRUPTS();
321 : :
322 : : /* no more entries in the bitmap */
323 [ + + ]: 208876 : if (!tbm_iterate(&sscan->st.rs_tbmiterator, tbmres))
324 : 10001 : return InvalidBlockNumber;
325 : :
326 : : /*
327 : : * Ignore any claimed entries past what we think is the end of the
328 : : * relation. It may have been extended after the start of our scan (we
329 : : * only hold an AccessShareLock, and it could be inserts from this
330 : : * backend). We don't take this optimization in SERIALIZABLE
331 : : * isolation though, as we need to examine all invisible tuples
332 : : * reachable by the index.
333 : : */
334 [ + + ]: 198875 : if (!IsolationIsSerializable() &&
335 [ - + ]: 198766 : tbmres->blockno >= hscan->rs_nblocks)
227 melanieplageman@gmai 336 :UBC 0 : continue;
337 : :
227 melanieplageman@gmai 338 :CBC 198875 : return tbmres->blockno;
339 : : }
340 : :
341 : : /* not reachable */
342 : : Assert(false);
343 : : }
344 : :
345 : : /* ----------------
346 : : * initscan - scan code common to heap_beginscan and heap_rescan
347 : : * ----------------
348 : : */
349 : : static void
3748 tgl@sss.pgh.pa.us 350 : 984859 : initscan(HeapScanDesc scan, ScanKey key, bool keep_startblock)
351 : : {
2423 andres@anarazel.de 352 : 984859 : ParallelBlockTableScanDesc bpscan = NULL;
353 : : bool allow_strat;
354 : : bool allow_sync;
355 : :
356 : : /*
357 : : * Determine the number of blocks we have to scan.
358 : : *
359 : : * It is sufficient to do this once at scan start, since any tuples added
360 : : * while the scan is in progress will be invisible to my snapshot anyway.
361 : : * (That is not true when using a non-MVCC snapshot. However, we couldn't
362 : : * guarantee to return tuples added after scan start anyway, since they
363 : : * might go into pages we already scanned. To guarantee consistent
364 : : * results for a non-MVCC snapshot, the caller must hold some higher-level
365 : : * lock that ensures the interesting tuple(s) won't change.)
366 : : */
367 [ + + ]: 984859 : if (scan->rs_base.rs_parallel != NULL)
368 : : {
369 : 2031 : bpscan = (ParallelBlockTableScanDesc) scan->rs_base.rs_parallel;
370 : 2031 : scan->rs_nblocks = bpscan->phs_nblocks;
371 : : }
372 : : else
373 : 982828 : scan->rs_nblocks = RelationGetNumberOfBlocks(scan->rs_base.rs_rd);
374 : :
375 : : /*
376 : : * If the table is large relative to NBuffers, use a bulk-read access
377 : : * strategy and enable synchronized scanning (see syncscan.c). Although
378 : : * the thresholds for these features could be different, we make them the
379 : : * same so that there are only two behaviors to tune rather than four.
380 : : * (However, some callers need to be able to disable one or both of these
381 : : * behaviors, independently of the size of the table; also there is a GUC
382 : : * variable that can disable synchronized scanning.)
383 : : *
384 : : * Note that table_block_parallelscan_initialize has a very similar test;
385 : : * if you change this, consider changing that one, too.
386 : : */
387 [ + + ]: 984857 : if (!RelationUsesLocalBuffers(scan->rs_base.rs_rd) &&
6716 tgl@sss.pgh.pa.us 388 [ + + ]: 977564 : scan->rs_nblocks > NBuffers / 4)
389 : : {
2354 andres@anarazel.de 390 : 13359 : allow_strat = (scan->rs_base.rs_flags & SO_ALLOW_STRAT) != 0;
391 : 13359 : allow_sync = (scan->rs_base.rs_flags & SO_ALLOW_SYNC) != 0;
392 : : }
393 : : else
6497 tgl@sss.pgh.pa.us 394 : 971498 : allow_strat = allow_sync = false;
395 : :
396 [ + + ]: 984857 : if (allow_strat)
397 : : {
398 : : /* During a rescan, keep the previous strategy object. */
6726 399 [ + + ]: 12085 : if (scan->rs_strategy == NULL)
400 : 11902 : scan->rs_strategy = GetAccessStrategy(BAS_BULKREAD);
401 : : }
402 : : else
403 : : {
404 [ - + ]: 972772 : if (scan->rs_strategy != NULL)
6726 tgl@sss.pgh.pa.us 405 :UBC 0 : FreeAccessStrategy(scan->rs_strategy);
6726 tgl@sss.pgh.pa.us 406 :CBC 972772 : scan->rs_strategy = NULL;
407 : : }
408 : :
2423 andres@anarazel.de 409 [ + + ]: 984857 : if (scan->rs_base.rs_parallel != NULL)
410 : : {
411 : : /* For parallel scan, believe whatever ParallelTableScanDesc says. */
2354 412 [ + + ]: 2031 : if (scan->rs_base.rs_parallel->phs_syncscan)
413 : 2 : scan->rs_base.rs_flags |= SO_ALLOW_SYNC;
414 : : else
415 : 2029 : scan->rs_base.rs_flags &= ~SO_ALLOW_SYNC;
416 : : }
3665 rhaas@postgresql.org 417 [ + + ]: 982826 : else if (keep_startblock)
418 : : {
419 : : /*
420 : : * When rescanning, we want to keep the previous startblock setting,
421 : : * so that rewinding a cursor doesn't generate surprising results.
422 : : * Reset the active syncscan setting, though.
423 : : */
2354 andres@anarazel.de 424 [ + + + + ]: 622419 : if (allow_sync && synchronize_seqscans)
425 : 50 : scan->rs_base.rs_flags |= SO_ALLOW_SYNC;
426 : : else
427 : 622369 : scan->rs_base.rs_flags &= ~SO_ALLOW_SYNC;
428 : : }
5984 tgl@sss.pgh.pa.us 429 [ + + + + ]: 360407 : else if (allow_sync && synchronize_seqscans)
430 : : {
2354 andres@anarazel.de 431 : 73 : scan->rs_base.rs_flags |= SO_ALLOW_SYNC;
2423 432 : 73 : scan->rs_startblock = ss_get_location(scan->rs_base.rs_rd, scan->rs_nblocks);
433 : : }
434 : : else
435 : : {
2354 436 : 360334 : scan->rs_base.rs_flags &= ~SO_ALLOW_SYNC;
6717 tgl@sss.pgh.pa.us 437 : 360334 : scan->rs_startblock = 0;
438 : : }
439 : :
4008 alvherre@alvh.no-ip. 440 : 984857 : scan->rs_numblocks = InvalidBlockNumber;
7276 tgl@sss.pgh.pa.us 441 : 984857 : scan->rs_inited = false;
8907 442 : 984857 : scan->rs_ctup.t_data = NULL;
7276 443 : 984857 : ItemPointerSetInvalid(&scan->rs_ctup.t_self);
8907 444 : 984857 : scan->rs_cbuf = InvalidBuffer;
7276 445 : 984857 : scan->rs_cblock = InvalidBlockNumber;
314 melanieplageman@gmai 446 : 984857 : scan->rs_ntuples = 0;
447 : 984857 : scan->rs_cindex = 0;
448 : :
449 : : /*
450 : : * Initialize to ForwardScanDirection because it is most common and
451 : : * because heap scans go forward before going backward (e.g. CURSORs).
452 : : */
568 tmunro@postgresql.or 453 : 984857 : scan->rs_dir = ForwardScanDirection;
454 : 984857 : scan->rs_prefetch_block = InvalidBlockNumber;
455 : :
456 : : /* page-at-a-time fields are always invalid when not rs_inited */
457 : :
458 : : /*
459 : : * copy the scan key, if appropriate
460 : : */
1335 tgl@sss.pgh.pa.us 461 [ + + + + ]: 984857 : if (key != NULL && scan->rs_base.rs_nkeys > 0)
2423 andres@anarazel.de 462 : 205815 : memcpy(scan->rs_base.rs_key, key, scan->rs_base.rs_nkeys * sizeof(ScanKeyData));
463 : :
464 : : /*
465 : : * Currently, we only have a stats counter for sequential heap scans (but
466 : : * e.g for bitmap scans the underlying bitmap index scans will be counted,
467 : : * and for sample scans we update stats for tuple fetches).
468 : : */
2354 469 [ + + ]: 984857 : if (scan->rs_base.rs_flags & SO_TYPE_SEQSCAN)
2423 470 [ + + + + : 964650 : pgstat_count_heap_scan(scan->rs_base.rs_rd);
+ + ]
10703 scrappy@hub.org 471 : 984857 : }
472 : :
473 : : /*
474 : : * heap_setscanlimits - restrict range of a heapscan
475 : : *
476 : : * startBlk is the page to start at
477 : : * numBlks is number of pages to scan (InvalidBlockNumber means "all")
478 : : */
479 : : void
2423 andres@anarazel.de 480 : 2818 : heap_setscanlimits(TableScanDesc sscan, BlockNumber startBlk, BlockNumber numBlks)
481 : : {
482 : 2818 : HeapScanDesc scan = (HeapScanDesc) sscan;
483 : :
3752 tgl@sss.pgh.pa.us 484 [ - + ]: 2818 : Assert(!scan->rs_inited); /* else too late to change */
485 : : /* else rs_startblock is significant */
2354 andres@anarazel.de 486 [ - + ]: 2818 : Assert(!(scan->rs_base.rs_flags & SO_ALLOW_SYNC));
487 : :
488 : : /* Check startBlk is valid (but allow case of zero blocks...) */
3752 tgl@sss.pgh.pa.us 489 [ + + - + ]: 2818 : Assert(startBlk == 0 || startBlk < scan->rs_nblocks);
490 : :
4008 alvherre@alvh.no-ip. 491 : 2818 : scan->rs_startblock = startBlk;
492 : 2818 : scan->rs_numblocks = numBlks;
493 : 2818 : }
494 : :
495 : : /*
496 : : * Per-tuple loop for heap_prepare_pagescan(). Pulled out so it can be called
497 : : * multiple times, with constant arguments for all_visible,
498 : : * check_serializable.
499 : : */
500 : : pg_attribute_always_inline
501 : : static int
569 andres@anarazel.de 502 : 2517883 : page_collect_tuples(HeapScanDesc scan, Snapshot snapshot,
503 : : Page page, Buffer buffer,
504 : : BlockNumber block, int lines,
505 : : bool all_visible, bool check_serializable)
506 : : {
570 507 : 2517883 : int ntup = 0;
508 : : OffsetNumber lineoff;
509 : :
510 [ + + ]: 127582118 : for (lineoff = FirstOffsetNumber; lineoff <= lines; lineoff++)
511 : : {
512 : 125064243 : ItemId lpp = PageGetItemId(page, lineoff);
513 : : HeapTupleData loctup;
514 : : bool valid;
515 : :
516 [ + + ]: 125064243 : if (!ItemIdIsNormal(lpp))
517 : 22940052 : continue;
518 : :
519 : 102124191 : loctup.t_data = (HeapTupleHeader) PageGetItem(page, lpp);
520 : 102124191 : loctup.t_len = ItemIdGetLength(lpp);
521 : 102124191 : loctup.t_tableOid = RelationGetRelid(scan->rs_base.rs_rd);
522 : 102124191 : ItemPointerSet(&(loctup.t_self), block, lineoff);
523 : :
524 [ + + ]: 102124191 : if (all_visible)
525 : 38820074 : valid = true;
526 : : else
527 : 63304117 : valid = HeapTupleSatisfiesVisibility(&loctup, snapshot, buffer);
528 : :
529 [ + + ]: 102124191 : if (check_serializable)
530 : 1409 : HeapCheckForSerializableConflictOut(valid, scan->rs_base.rs_rd,
531 : : &loctup, buffer, snapshot);
532 : :
533 [ + + ]: 102124183 : if (valid)
534 : : {
535 : 95364508 : scan->rs_vistuples[ntup] = lineoff;
536 : 95364508 : ntup++;
537 : : }
538 : : }
539 : :
540 [ - + ]: 2517875 : Assert(ntup <= MaxHeapTuplesPerPage);
541 : :
542 : 2517875 : return ntup;
543 : : }
544 : :
545 : : /*
546 : : * heap_prepare_pagescan - Prepare current scan page to be scanned in pagemode
547 : : *
548 : : * Preparation currently consists of 1. prune the scan's rs_cbuf page, and 2.
549 : : * fill the rs_vistuples[] array with the OffsetNumbers of visible tuples.
550 : : */
551 : : void
572 drowley@postgresql.o 552 : 2517883 : heap_prepare_pagescan(TableScanDesc sscan)
553 : : {
2423 andres@anarazel.de 554 : 2517883 : HeapScanDesc scan = (HeapScanDesc) sscan;
572 drowley@postgresql.o 555 : 2517883 : Buffer buffer = scan->rs_cbuf;
556 : 2517883 : BlockNumber block = scan->rs_cblock;
557 : : Snapshot snapshot;
558 : : Page page;
559 : : int lines;
560 : : bool all_visible;
561 : : bool check_serializable;
562 : :
563 [ - + ]: 2517883 : Assert(BufferGetBlockNumber(buffer) == block);
564 : :
565 : : /* ensure we're not accidentally being used when not in pagemode */
566 [ - + ]: 2517883 : Assert(scan->rs_base.rs_flags & SO_ALLOW_PAGEMODE);
2423 andres@anarazel.de 567 : 2517883 : snapshot = scan->rs_base.rs_snapshot;
568 : :
569 : : /*
570 : : * Prune and repair fragmentation for the whole page, if possible.
571 : : */
572 : 2517883 : heap_page_prune_opt(scan->rs_base.rs_rd, buffer);
573 : :
574 : : /*
575 : : * We must hold share lock on the buffer content while examining tuple
576 : : * visibility. Afterwards, however, the tuples we have found to be
577 : : * visible are guaranteed good as long as we hold the buffer pin.
578 : : */
7276 tgl@sss.pgh.pa.us 579 : 2517883 : LockBuffer(buffer, BUFFER_LOCK_SHARE);
580 : :
1077 peter@eisentraut.org 581 : 2517883 : page = BufferGetPage(buffer);
582 : 2517883 : lines = PageGetMaxOffsetNumber(page);
583 : :
584 : : /*
585 : : * If the all-visible flag indicates that all tuples on the page are
586 : : * visible to everyone, we can skip the per-tuple visibility tests.
587 : : *
588 : : * Note: In hot standby, a tuple that's already visible to all
589 : : * transactions on the primary might still be invisible to a read-only
590 : : * transaction in the standby. We partly handle this problem by tracking
591 : : * the minimum xmin of visible tuples as the cut-off XID while marking a
592 : : * page all-visible on the primary and WAL log that along with the
593 : : * visibility map SET operation. In hot standby, we wait for (or abort)
594 : : * all transactions that can potentially may not see one or more tuples on
595 : : * the page. That's how index-only scans work fine in hot standby. A
596 : : * crucial difference between index-only scans and heap scans is that the
597 : : * index-only scan completely relies on the visibility map where as heap
598 : : * scan looks at the page-level PD_ALL_VISIBLE flag. We are not sure if
599 : : * the page-level flag can be trusted in the same way, because it might
600 : : * get propagated somehow without being explicitly WAL-logged, e.g. via a
601 : : * full page write. Until we can prove that beyond doubt, let's check each
602 : : * tuple for visibility the hard way.
603 : : */
604 [ + + + + ]: 2517883 : all_visible = PageIsAllVisible(page) && !snapshot->takenDuringRecovery;
605 : : check_serializable =
570 andres@anarazel.de 606 : 2517883 : CheckForSerializableConflictOutNeeded(scan->rs_base.rs_rd, snapshot);
607 : :
608 : : /*
609 : : * We call page_collect_tuples() with constant arguments, to get the
610 : : * compiler to constant fold the constant arguments. Separate calls with
611 : : * constant arguments, rather than variables, are needed on several
612 : : * compilers to actually perform constant folding.
613 : : */
614 [ + + ]: 2517883 : if (likely(all_visible))
615 : : {
616 [ + - ]: 936482 : if (likely(!check_serializable))
569 617 : 936482 : scan->rs_ntuples = page_collect_tuples(scan, snapshot, page, buffer,
618 : : block, lines, true, false);
619 : : else
569 andres@anarazel.de 620 :UBC 0 : scan->rs_ntuples = page_collect_tuples(scan, snapshot, page, buffer,
621 : : block, lines, true, true);
622 : : }
623 : : else
624 : : {
570 andres@anarazel.de 625 [ + + ]:CBC 1581401 : if (likely(!check_serializable))
569 626 : 1580778 : scan->rs_ntuples = page_collect_tuples(scan, snapshot, page, buffer,
627 : : block, lines, false, false);
628 : : else
629 : 623 : scan->rs_ntuples = page_collect_tuples(scan, snapshot, page, buffer,
630 : : block, lines, false, true);
631 : : }
632 : :
7276 tgl@sss.pgh.pa.us 633 : 2517875 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
634 : 2517875 : }
635 : :
636 : : /*
637 : : * heap_fetch_next_buffer - read and pin the next block from MAIN_FORKNUM.
638 : : *
639 : : * Read the next block of the scan relation from the read stream and save it
640 : : * in the scan descriptor. It is already pinned.
641 : : */
642 : : static inline void
572 drowley@postgresql.o 643 : 3419753 : heap_fetch_next_buffer(HeapScanDesc scan, ScanDirection dir)
644 : : {
568 tmunro@postgresql.or 645 [ - + ]: 3419753 : Assert(scan->rs_read_stream);
646 : :
647 : : /* release previous scan buffer, if any */
572 drowley@postgresql.o 648 [ + + ]: 3419753 : if (BufferIsValid(scan->rs_cbuf))
649 : : {
650 : 2454730 : ReleaseBuffer(scan->rs_cbuf);
651 : 2454730 : scan->rs_cbuf = InvalidBuffer;
652 : : }
653 : :
654 : : /*
655 : : * Be sure to check for interrupts at least once per page. Checks at
656 : : * higher code levels won't be able to stop a seqscan that encounters many
657 : : * pages' worth of consecutive dead tuples.
658 : : */
659 [ + + ]: 3419753 : CHECK_FOR_INTERRUPTS();
660 : :
661 : : /*
662 : : * If the scan direction is changing, reset the prefetch block to the
663 : : * current block. Otherwise, we will incorrectly prefetch the blocks
664 : : * between the prefetch block and the current block again before
665 : : * prefetching blocks in the new, correct scan direction.
666 : : */
568 tmunro@postgresql.or 667 [ + + ]: 3419750 : if (unlikely(scan->rs_dir != dir))
668 : : {
669 : 76 : scan->rs_prefetch_block = scan->rs_cblock;
670 : 76 : read_stream_reset(scan->rs_read_stream);
671 : : }
672 : :
673 : 3419750 : scan->rs_dir = dir;
674 : :
675 : 3419750 : scan->rs_cbuf = read_stream_next_buffer(scan->rs_read_stream, NULL);
676 [ + + ]: 3419728 : if (BufferIsValid(scan->rs_cbuf))
677 : 2607832 : scan->rs_cblock = BufferGetBlockNumber(scan->rs_cbuf);
572 drowley@postgresql.o 678 : 3419728 : }
679 : :
680 : : /*
681 : : * heapgettup_initial_block - return the first BlockNumber to scan
682 : : *
683 : : * Returns InvalidBlockNumber when there are no blocks to scan. This can
684 : : * occur with empty tables and in parallel scans when parallel workers get all
685 : : * of the pages before we can get a chance to get our first page.
686 : : */
687 : : static pg_noinline BlockNumber
999 688 : 963452 : heapgettup_initial_block(HeapScanDesc scan, ScanDirection dir)
689 : : {
690 [ - + ]: 963452 : Assert(!scan->rs_inited);
568 tmunro@postgresql.or 691 [ - + ]: 963452 : Assert(scan->rs_base.rs_parallel == NULL);
692 : :
693 : : /* When there are no pages to scan, return InvalidBlockNumber */
999 drowley@postgresql.o 694 [ + + + + ]: 963452 : if (scan->rs_nblocks == 0 || scan->rs_numblocks == 0)
695 : 500439 : return InvalidBlockNumber;
696 : :
697 [ + + ]: 463013 : if (ScanDirectionIsForward(dir))
698 : : {
568 tmunro@postgresql.or 699 : 462982 : return scan->rs_startblock;
700 : : }
701 : : else
702 : : {
703 : : /*
704 : : * Disable reporting to syncscan logic in a backwards scan; it's not
705 : : * very likely anyone else is doing the same thing at the same time,
706 : : * and much more likely that we'll just bollix things for forward
707 : : * scanners.
708 : : */
999 drowley@postgresql.o 709 : 31 : scan->rs_base.rs_flags &= ~SO_ALLOW_SYNC;
710 : :
711 : : /*
712 : : * Start from last page of the scan. Ensure we take into account
713 : : * rs_numblocks if it's been adjusted by heap_setscanlimits().
714 : : */
715 [ + + ]: 31 : if (scan->rs_numblocks != InvalidBlockNumber)
716 : 3 : return (scan->rs_startblock + scan->rs_numblocks - 1) % scan->rs_nblocks;
717 : :
718 [ - + ]: 28 : if (scan->rs_startblock > 0)
999 drowley@postgresql.o 719 :UBC 0 : return scan->rs_startblock - 1;
720 : :
999 drowley@postgresql.o 721 :CBC 28 : return scan->rs_nblocks - 1;
722 : : }
723 : : }
724 : :
725 : :
726 : : /*
727 : : * heapgettup_start_page - helper function for heapgettup()
728 : : *
729 : : * Return the next page to scan based on the scan->rs_cbuf and set *linesleft
730 : : * to the number of tuples on this page. Also set *lineoff to the first
731 : : * offset to scan with forward scans getting the first offset and backward
732 : : * getting the final offset on the page.
733 : : */
734 : : static Page
998 735 : 94226 : heapgettup_start_page(HeapScanDesc scan, ScanDirection dir, int *linesleft,
736 : : OffsetNumber *lineoff)
737 : : {
738 : : Page page;
739 : :
740 [ - + ]: 94226 : Assert(scan->rs_inited);
741 [ - + ]: 94226 : Assert(BufferIsValid(scan->rs_cbuf));
742 : :
743 : : /* Caller is responsible for ensuring buffer is locked if needed */
744 : 94226 : page = BufferGetPage(scan->rs_cbuf);
745 : :
994 746 : 94226 : *linesleft = PageGetMaxOffsetNumber(page) - FirstOffsetNumber + 1;
747 : :
998 748 [ + - ]: 94226 : if (ScanDirectionIsForward(dir))
749 : 94226 : *lineoff = FirstOffsetNumber;
750 : : else
998 drowley@postgresql.o 751 :UBC 0 : *lineoff = (OffsetNumber) (*linesleft);
752 : :
753 : : /* lineoff now references the physically previous or next tid */
998 drowley@postgresql.o 754 :CBC 94226 : return page;
755 : : }
756 : :
757 : :
758 : : /*
759 : : * heapgettup_continue_page - helper function for heapgettup()
760 : : *
761 : : * Return the next page to scan based on the scan->rs_cbuf and set *linesleft
762 : : * to the number of tuples left to scan on this page. Also set *lineoff to
763 : : * the next offset to scan according to the ScanDirection in 'dir'.
764 : : */
765 : : static inline Page
766 : 7830256 : heapgettup_continue_page(HeapScanDesc scan, ScanDirection dir, int *linesleft,
767 : : OffsetNumber *lineoff)
768 : : {
769 : : Page page;
770 : :
771 [ - + ]: 7830256 : Assert(scan->rs_inited);
772 [ - + ]: 7830256 : Assert(BufferIsValid(scan->rs_cbuf));
773 : :
774 : : /* Caller is responsible for ensuring buffer is locked if needed */
775 : 7830256 : page = BufferGetPage(scan->rs_cbuf);
776 : :
777 [ + - ]: 7830256 : if (ScanDirectionIsForward(dir))
778 : : {
779 : 7830256 : *lineoff = OffsetNumberNext(scan->rs_coffset);
780 : 7830256 : *linesleft = PageGetMaxOffsetNumber(page) - (*lineoff) + 1;
781 : : }
782 : : else
783 : : {
784 : : /*
785 : : * The previous returned tuple may have been vacuumed since the
786 : : * previous scan when we use a non-MVCC snapshot, so we must
787 : : * re-establish the lineoff <= PageGetMaxOffsetNumber(page) invariant
788 : : */
998 drowley@postgresql.o 789 [ # # ]:UBC 0 : *lineoff = Min(PageGetMaxOffsetNumber(page), OffsetNumberPrev(scan->rs_coffset));
790 : 0 : *linesleft = *lineoff;
791 : : }
792 : :
793 : : /* lineoff now references the physically previous or next tid */
998 drowley@postgresql.o 794 :CBC 7830256 : return page;
795 : : }
796 : :
797 : : /*
798 : : * heapgettup_advance_block - helper for heap_fetch_next_buffer()
799 : : *
800 : : * Given the current block number, the scan direction, and various information
801 : : * contained in the scan descriptor, calculate the BlockNumber to scan next
802 : : * and return it. If there are no further blocks to scan, return
803 : : * InvalidBlockNumber to indicate this fact to the caller.
804 : : *
805 : : * This should not be called to determine the initial block number -- only for
806 : : * subsequent blocks.
807 : : *
808 : : * This also adjusts rs_numblocks when a limit has been imposed by
809 : : * heap_setscanlimits().
810 : : */
811 : : static inline BlockNumber
812 : 2528942 : heapgettup_advance_block(HeapScanDesc scan, BlockNumber block, ScanDirection dir)
813 : : {
568 tmunro@postgresql.or 814 [ - + ]: 2528942 : Assert(scan->rs_base.rs_parallel == NULL);
815 : :
816 [ + + ]: 2528942 : if (likely(ScanDirectionIsForward(dir)))
817 : : {
818 : 2528884 : block++;
819 : :
820 : : /* wrap back to the start of the heap */
821 [ + + ]: 2528884 : if (block >= scan->rs_nblocks)
822 : 367598 : block = 0;
823 : :
824 : : /*
825 : : * Report our new scan position for synchronization purposes. We don't
826 : : * do that when moving backwards, however. That would just mess up any
827 : : * other forward-moving scanners.
828 : : *
829 : : * Note: we do this before checking for end of scan so that the final
830 : : * state of the position hint is back at the start of the rel. That's
831 : : * not strictly necessary, but otherwise when you run the same query
832 : : * multiple times the starting position would shift a little bit
833 : : * backwards on every invocation, which is confusing. We don't
834 : : * guarantee any specific ordering in general, though.
835 : : */
836 [ + + ]: 2528884 : if (scan->rs_base.rs_flags & SO_ALLOW_SYNC)
837 : 11349 : ss_report_location(scan->rs_base.rs_rd, block);
838 : :
839 : : /* we're done if we're back at where we started */
840 [ + + ]: 2528884 : if (block == scan->rs_startblock)
841 : 367557 : return InvalidBlockNumber;
842 : :
843 : : /* check if the limit imposed by heap_setscanlimits() is met */
844 [ + + ]: 2161327 : if (scan->rs_numblocks != InvalidBlockNumber)
845 : : {
846 [ + + ]: 2466 : if (--scan->rs_numblocks == 0)
847 : 1532 : return InvalidBlockNumber;
848 : : }
849 : :
850 : 2159795 : return block;
851 : : }
852 : : else
853 : : {
854 : : /* we're done if the last block is the start position */
998 drowley@postgresql.o 855 [ + - ]: 58 : if (block == scan->rs_startblock)
856 : 58 : return InvalidBlockNumber;
857 : :
858 : : /* check if the limit imposed by heap_setscanlimits() is met */
998 drowley@postgresql.o 859 [ # # ]:UBC 0 : if (scan->rs_numblocks != InvalidBlockNumber)
860 : : {
861 [ # # ]: 0 : if (--scan->rs_numblocks == 0)
862 : 0 : return InvalidBlockNumber;
863 : : }
864 : :
865 : : /* wrap to the end of the heap when the last page was page 0 */
866 [ # # ]: 0 : if (block == 0)
867 : 0 : block = scan->rs_nblocks;
868 : :
869 : 0 : block--;
870 : :
871 : 0 : return block;
872 : : }
873 : : }
874 : :
875 : : /* ----------------
876 : : * heapgettup - fetch next heap tuple
877 : : *
878 : : * Initialize the scan if not already done; then advance to the next
879 : : * tuple as indicated by "dir"; return the next tuple in scan->rs_ctup,
880 : : * or set scan->rs_ctup.t_data = NULL if no more tuples.
881 : : *
882 : : * Note: the reason nkeys/key are passed separately, even though they are
883 : : * kept in the scan descriptor, is that the caller may not want us to check
884 : : * the scankeys.
885 : : *
886 : : * Note: when we fall off the end of the scan in either direction, we
887 : : * reset rs_inited. This means that a further request with the same
888 : : * scan direction will restart the scan, which is a bit odd, but a
889 : : * request with the opposite scan direction will start a fresh scan
890 : : * in the proper direction. The latter is required behavior for cursors,
891 : : * while the former case is generally undefined behavior in Postgres
892 : : * so we don't care too much.
893 : : * ----------------
894 : : */
895 : : static void
7276 tgl@sss.pgh.pa.us 896 :CBC 7850603 : heapgettup(HeapScanDesc scan,
897 : : ScanDirection dir,
898 : : int nkeys,
899 : : ScanKey key)
900 : : {
901 : 7850603 : HeapTuple tuple = &(scan->rs_ctup);
902 : : Page page;
903 : : OffsetNumber lineoff;
904 : : int linesleft;
905 : :
572 drowley@postgresql.o 906 [ + + ]: 7850603 : if (likely(scan->rs_inited))
907 : : {
908 : : /* continue from previously returned page/tuple */
998 909 : 7830256 : LockBuffer(scan->rs_cbuf, BUFFER_LOCK_SHARE);
910 : 7830256 : page = heapgettup_continue_page(scan, dir, &linesleft, &lineoff);
994 911 : 7830256 : goto continue_page;
912 : : }
913 : :
914 : : /*
915 : : * advance the scan until we find a qualifying tuple or run out of stuff
916 : : * to scan
917 : : */
918 : : while (true)
919 : : {
572 920 : 114423 : heap_fetch_next_buffer(scan, dir);
921 : :
922 : : /* did we run out of blocks to scan? */
923 [ + + ]: 114423 : if (!BufferIsValid(scan->rs_cbuf))
924 : 20197 : break;
925 : :
926 [ - + ]: 94226 : Assert(BufferGetBlockNumber(scan->rs_cbuf) == scan->rs_cblock);
927 : :
994 928 : 94226 : LockBuffer(scan->rs_cbuf, BUFFER_LOCK_SHARE);
929 : 94226 : page = heapgettup_start_page(scan, dir, &linesleft, &lineoff);
930 : 7924482 : continue_page:
931 : :
932 : : /*
933 : : * Only continue scanning the page while we have lines left.
934 : : *
935 : : * Note that this protects us from accessing line pointers past
936 : : * PageGetMaxOffsetNumber(); both for forward scans when we resume the
937 : : * table scan, and for when we start scanning a new page.
938 : : */
939 [ + + ]: 7959804 : for (; linesleft > 0; linesleft--, lineoff += dir)
940 : : {
941 : : bool visible;
942 : 7865728 : ItemId lpp = PageGetItemId(page, lineoff);
943 : :
944 [ + + ]: 7865728 : if (!ItemIdIsNormal(lpp))
945 : 30092 : continue;
946 : :
947 : 7835636 : tuple->t_data = (HeapTupleHeader) PageGetItem(page, lpp);
948 : 7835636 : tuple->t_len = ItemIdGetLength(lpp);
572 949 : 7835636 : ItemPointerSet(&(tuple->t_self), scan->rs_cblock, lineoff);
950 : :
994 951 : 7835636 : visible = HeapTupleSatisfiesVisibility(tuple,
952 : : scan->rs_base.rs_snapshot,
953 : : scan->rs_cbuf);
954 : :
955 : 7835636 : HeapCheckForSerializableConflictOut(visible, scan->rs_base.rs_rd,
956 : : tuple, scan->rs_cbuf,
957 : : scan->rs_base.rs_snapshot);
958 : :
959 : : /* skip tuples not visible to this snapshot */
960 [ + + ]: 7835636 : if (!visible)
961 : 5230 : continue;
962 : :
963 : : /* skip any tuples that don't match the scan key */
964 [ - + ]: 7830406 : if (key != NULL &&
994 drowley@postgresql.o 965 [ # # ]:UBC 0 : !HeapKeyTest(tuple, RelationGetDescr(scan->rs_base.rs_rd),
966 : : nkeys, key))
967 : 0 : continue;
968 : :
994 drowley@postgresql.o 969 :CBC 7830406 : LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
970 : 7830406 : scan->rs_coffset = lineoff;
971 : 7830406 : return;
972 : : }
973 : :
974 : : /*
975 : : * if we get here, it means we've exhausted the items on this page and
976 : : * it's time to move to the next.
977 : : */
7276 tgl@sss.pgh.pa.us 978 : 94076 : LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
979 : : }
980 : :
981 : : /* end of scan */
994 drowley@postgresql.o 982 [ - + ]: 20197 : if (BufferIsValid(scan->rs_cbuf))
994 drowley@postgresql.o 983 :UBC 0 : ReleaseBuffer(scan->rs_cbuf);
984 : :
994 drowley@postgresql.o 985 :CBC 20197 : scan->rs_cbuf = InvalidBuffer;
986 : 20197 : scan->rs_cblock = InvalidBlockNumber;
568 tmunro@postgresql.or 987 : 20197 : scan->rs_prefetch_block = InvalidBlockNumber;
994 drowley@postgresql.o 988 : 20197 : tuple->t_data = NULL;
989 : 20197 : scan->rs_inited = false;
990 : : }
991 : :
992 : : /* ----------------
993 : : * heapgettup_pagemode - fetch next heap tuple in page-at-a-time mode
994 : : *
995 : : * Same API as heapgettup, but used in page-at-a-time mode
996 : : *
997 : : * The internal logic is much the same as heapgettup's too, but there are some
998 : : * differences: we do not take the buffer content lock (that only needs to
999 : : * happen inside heap_prepare_pagescan), and we iterate through just the
1000 : : * tuples listed in rs_vistuples[] rather than all tuples on the page. Notice
1001 : : * that lineindex is 0-based, where the corresponding loop variable lineoff in
1002 : : * heapgettup is 1-based.
1003 : : * ----------------
1004 : : */
1005 : : static void
7276 tgl@sss.pgh.pa.us 1006 : 48446118 : heapgettup_pagemode(HeapScanDesc scan,
1007 : : ScanDirection dir,
1008 : : int nkeys,
1009 : : ScanKey key)
1010 : : {
1011 : 48446118 : HeapTuple tuple = &(scan->rs_ctup);
1012 : : Page page;
1013 : : uint32 lineindex;
1014 : : uint32 linesleft;
1015 : :
572 drowley@postgresql.o 1016 [ + + ]: 48446118 : if (likely(scan->rs_inited))
1017 : : {
1018 : : /* continue from previously returned page/tuple */
998 1019 : 47501442 : page = BufferGetPage(scan->rs_cbuf);
1020 : :
1021 : 47501442 : lineindex = scan->rs_cindex + dir;
1022 [ + + ]: 47501442 : if (ScanDirectionIsForward(dir))
1023 : 47501114 : linesleft = scan->rs_ntuples - lineindex;
1024 : : else
1025 : 328 : linesleft = scan->rs_cindex;
1026 : : /* lineindex now references the next or previous visible tid */
1027 : :
994 1028 : 47501442 : goto continue_page;
1029 : : }
1030 : :
1031 : : /*
1032 : : * advance the scan until we find a qualifying tuple or run out of stuff
1033 : : * to scan
1034 : : */
1035 : : while (true)
1036 : : {
572 1037 : 3305330 : heap_fetch_next_buffer(scan, dir);
1038 : :
1039 : : /* did we run out of blocks to scan? */
1040 [ + + ]: 3305305 : if (!BufferIsValid(scan->rs_cbuf))
1041 : 791699 : break;
1042 : :
1043 [ - + ]: 2513606 : Assert(BufferGetBlockNumber(scan->rs_cbuf) == scan->rs_cblock);
1044 : :
1045 : : /* prune the page and determine visible tuple offsets */
1046 : 2513606 : heap_prepare_pagescan((TableScanDesc) scan);
994 1047 : 2513598 : page = BufferGetPage(scan->rs_cbuf);
1048 : 2513598 : linesleft = scan->rs_ntuples;
1049 [ + + ]: 2513598 : lineindex = ScanDirectionIsForward(dir) ? 0 : linesleft - 1;
1050 : :
1051 : : /* block is the same for all tuples, set it once outside the loop */
210 heikki.linnakangas@i 1052 : 2513598 : ItemPointerSetBlockNumber(&tuple->t_self, scan->rs_cblock);
1053 : :
1054 : : /* lineindex now references the next or previous visible tid */
994 drowley@postgresql.o 1055 : 50015040 : continue_page:
1056 : :
1057 [ + + ]: 94705350 : for (; linesleft > 0; linesleft--, lineindex += dir)
1058 : : {
1059 : : ItemId lpp;
1060 : : OffsetNumber lineoff;
1061 : :
314 melanieplageman@gmai 1062 [ - + ]: 92344696 : Assert(lineindex <= scan->rs_ntuples);
7276 tgl@sss.pgh.pa.us 1063 : 92344696 : lineoff = scan->rs_vistuples[lineindex];
1077 peter@eisentraut.org 1064 : 92344696 : lpp = PageGetItemId(page, lineoff);
6621 tgl@sss.pgh.pa.us 1065 [ - + ]: 92344696 : Assert(ItemIdIsNormal(lpp));
1066 : :
1077 peter@eisentraut.org 1067 : 92344696 : tuple->t_data = (HeapTupleHeader) PageGetItem(page, lpp);
7276 tgl@sss.pgh.pa.us 1068 : 92344696 : tuple->t_len = ItemIdGetLength(lpp);
210 heikki.linnakangas@i 1069 : 92344696 : ItemPointerSetOffsetNumber(&tuple->t_self, lineoff);
1070 : :
1071 : : /* skip any tuples that don't match the scan key */
994 drowley@postgresql.o 1072 [ + + ]: 92344696 : if (key != NULL &&
1073 [ + + ]: 45001286 : !HeapKeyTest(tuple, RelationGetDescr(scan->rs_base.rs_rd),
1074 : : nkeys, key))
1075 : 44690310 : continue;
1076 : :
1077 : 47654386 : scan->rs_cindex = lineindex;
1078 : 47654386 : return;
1079 : : }
1080 : : }
1081 : :
1082 : : /* end of scan */
1083 [ - + ]: 791699 : if (BufferIsValid(scan->rs_cbuf))
994 drowley@postgresql.o 1084 :UBC 0 : ReleaseBuffer(scan->rs_cbuf);
994 drowley@postgresql.o 1085 :CBC 791699 : scan->rs_cbuf = InvalidBuffer;
1086 : 791699 : scan->rs_cblock = InvalidBlockNumber;
568 tmunro@postgresql.or 1087 : 791699 : scan->rs_prefetch_block = InvalidBlockNumber;
994 drowley@postgresql.o 1088 : 791699 : tuple->t_data = NULL;
1089 : 791699 : scan->rs_inited = false;
1090 : : }
1091 : :
1092 : :
1093 : : /* ----------------------------------------------------------------
1094 : : * heap access method interface
1095 : : * ----------------------------------------------------------------
1096 : : */
1097 : :
1098 : :
1099 : : TableScanDesc
8562 tgl@sss.pgh.pa.us 1100 : 362386 : heap_beginscan(Relation relation, Snapshot snapshot,
1101 : : int nkeys, ScanKey key,
1102 : : ParallelTableScanDesc parallel_scan,
1103 : : uint32 flags)
1104 : : {
1105 : : HeapScanDesc scan;
1106 : :
1107 : : /*
1108 : : * increment relation ref count while scanning relation
1109 : : *
1110 : : * This is just to make really sure the relcache entry won't go away while
1111 : : * the scan has a pointer to it. Caller should be holding the rel open
1112 : : * anyway, so this is redundant in all normal scenarios...
1113 : : */
9120 1114 : 362386 : RelationIncrementReferenceCount(relation);
1115 : :
1116 : : /*
1117 : : * allocate and initialize scan descriptor
1118 : : */
285 melanieplageman@gmai 1119 [ + + ]: 362386 : if (flags & SO_TYPE_BITMAPSCAN)
1120 : : {
1121 : 7929 : BitmapHeapScanDesc bscan = palloc(sizeof(BitmapHeapScanDescData));
1122 : :
1123 : : /*
1124 : : * Bitmap Heap scans do not have any fields that a normal Heap Scan
1125 : : * does not have, so no special initializations required here.
1126 : : */
1127 : 7929 : scan = (HeapScanDesc) bscan;
1128 : : }
1129 : : else
1130 : 354457 : scan = (HeapScanDesc) palloc(sizeof(HeapScanDescData));
1131 : :
2423 andres@anarazel.de 1132 : 362386 : scan->rs_base.rs_rd = relation;
1133 : 362386 : scan->rs_base.rs_snapshot = snapshot;
1134 : 362386 : scan->rs_base.rs_nkeys = nkeys;
2354 1135 : 362386 : scan->rs_base.rs_flags = flags;
2423 1136 : 362386 : scan->rs_base.rs_parallel = parallel_scan;
2354 1137 : 362386 : scan->rs_strategy = NULL; /* set in initscan */
227 melanieplageman@gmai 1138 : 362386 : scan->rs_cbuf = InvalidBuffer;
1139 : :
1140 : : /*
1141 : : * Disable page-at-a-time mode if it's not a MVCC-safe snapshot.
1142 : : */
2354 andres@anarazel.de 1143 [ + + + + : 362386 : if (!(snapshot && IsMVCCSnapshot(snapshot)))
+ + ]
1144 : 29093 : scan->rs_base.rs_flags &= ~SO_ALLOW_PAGEMODE;
1145 : :
1146 : : /* Check that a historic snapshot is not used for non-catalog tables */
67 heikki.linnakangas@i 1147 [ + + ]:GNC 362386 : if (snapshot &&
1148 [ + + ]: 353642 : IsHistoricMVCCSnapshot(snapshot) &&
1149 [ + - + - : 641 : !RelationIsAccessibleInLogicalDecoding(relation))
- + - - -
- - + - -
- - - - -
- - - ]
1150 : : {
67 heikki.linnakangas@i 1151 [ # # ]:UNC 0 : ereport(ERROR,
1152 : : (errcode(ERRCODE_INVALID_TRANSACTION_STATE),
1153 : : errmsg("cannot query non-catalog table \"%s\" during logical decoding",
1154 : : RelationGetRelationName(relation))));
1155 : : }
1156 : :
1157 : : /*
1158 : : * For seqscan and sample scans in a serializable transaction, acquire a
1159 : : * predicate lock on the entire relation. This is required not only to
1160 : : * lock all the matching tuples, but also to conflict with new insertions
1161 : : * into the table. In an indexscan, we take page locks on the index pages
1162 : : * covering the range specified in the scan qual, but in a heap scan there
1163 : : * is nothing more fine-grained to lock. A bitmap scan is a different
1164 : : * story, there we have already scanned the index and locked the index
1165 : : * pages covering the predicate. But in that case we still have to lock
1166 : : * any matching heap tuples. For sample scan we could optimize the locking
1167 : : * to be at least page-level granularity, but we'd need to add per-tuple
1168 : : * locking for that.
1169 : : */
2354 andres@anarazel.de 1170 [ + + ]:CBC 362386 : if (scan->rs_base.rs_flags & (SO_TYPE_SEQSCAN | SO_TYPE_SAMPLESCAN))
1171 : : {
1172 : : /*
1173 : : * Ensure a missing snapshot is noticed reliably, even if the
1174 : : * isolation mode means predicate locking isn't performed (and
1175 : : * therefore the snapshot isn't used here).
1176 : : */
1177 [ - + ]: 344393 : Assert(snapshot);
5235 heikki.linnakangas@i 1178 : 344393 : PredicateLockRelation(relation, snapshot);
1179 : : }
1180 : :
1181 : : /* we only need to set this up once */
7276 tgl@sss.pgh.pa.us 1182 : 362386 : scan->rs_ctup.t_tableOid = RelationGetRelid(relation);
1183 : :
1184 : : /*
1185 : : * Allocate memory to keep track of page allocation for parallel workers
1186 : : * when doing a parallel scan.
1187 : : */
1673 drowley@postgresql.o 1188 [ + + ]: 362386 : if (parallel_scan != NULL)
1189 : 1977 : scan->rs_parallelworkerdata = palloc(sizeof(ParallelBlockTableScanWorkerData));
1190 : : else
1191 : 360409 : scan->rs_parallelworkerdata = NULL;
1192 : :
1193 : : /*
1194 : : * we do this here instead of in initscan() because heap_rescan also calls
1195 : : * initscan() and we don't want to allocate memory again
1196 : : */
8562 tgl@sss.pgh.pa.us 1197 [ + + ]: 362386 : if (nkeys > 0)
2423 andres@anarazel.de 1198 : 205815 : scan->rs_base.rs_key = (ScanKey) palloc(sizeof(ScanKeyData) * nkeys);
1199 : : else
1200 : 156571 : scan->rs_base.rs_key = NULL;
1201 : :
5984 tgl@sss.pgh.pa.us 1202 : 362386 : initscan(scan, key, false);
1203 : :
568 tmunro@postgresql.or 1204 : 362384 : scan->rs_read_stream = NULL;
1205 : :
1206 : : /*
1207 : : * Set up a read stream for sequential scans and TID range scans. This
1208 : : * should be done after initscan() because initscan() allocates the
1209 : : * BufferAccessStrategy object passed to the read stream API.
1210 : : */
1211 [ + + ]: 362384 : if (scan->rs_base.rs_flags & SO_TYPE_SEQSCAN ||
1212 [ + + ]: 18066 : scan->rs_base.rs_flags & SO_TYPE_TIDRANGESCAN)
1213 : 345243 : {
1214 : : ReadStreamBlockNumberCB cb;
1215 : :
1216 [ + + ]: 345243 : if (scan->rs_base.rs_parallel)
1217 : 1977 : cb = heap_scan_stream_read_next_parallel;
1218 : : else
1219 : 343266 : cb = heap_scan_stream_read_next_serial;
1220 : :
1221 : : /* ---
1222 : : * It is safe to use batchmode as the only locks taken by `cb`
1223 : : * are never taken while waiting for IO:
1224 : : * - SyncScanLock is used in the non-parallel case
1225 : : * - in the parallel case, only spinlocks and atomics are used
1226 : : * ---
1227 : : */
212 andres@anarazel.de 1228 : 345243 : scan->rs_read_stream = read_stream_begin_relation(READ_STREAM_SEQUENTIAL |
1229 : : READ_STREAM_USE_BATCHING,
1230 : : scan->rs_strategy,
1231 : : scan->rs_base.rs_rd,
1232 : : MAIN_FORKNUM,
1233 : : cb,
1234 : : scan,
1235 : : 0);
1236 : : }
227 melanieplageman@gmai 1237 [ + + ]: 17141 : else if (scan->rs_base.rs_flags & SO_TYPE_BITMAPSCAN)
1238 : : {
208 1239 : 7929 : scan->rs_read_stream = read_stream_begin_relation(READ_STREAM_DEFAULT |
1240 : : READ_STREAM_USE_BATCHING,
1241 : : scan->rs_strategy,
1242 : : scan->rs_base.rs_rd,
1243 : : MAIN_FORKNUM,
1244 : : bitmapheap_stream_read_next,
1245 : : scan,
1246 : : sizeof(TBMIterateResult));
1247 : : }
1248 : :
1249 : :
2423 andres@anarazel.de 1250 : 362384 : return (TableScanDesc) scan;
1251 : : }
1252 : :
1253 : : void
1254 : 622473 : heap_rescan(TableScanDesc sscan, ScanKey key, bool set_params,
1255 : : bool allow_strat, bool allow_sync, bool allow_pagemode)
1256 : : {
1257 : 622473 : HeapScanDesc scan = (HeapScanDesc) sscan;
1258 : :
1259 [ + + ]: 622473 : if (set_params)
1260 : : {
2354 1261 [ + - ]: 15 : if (allow_strat)
1262 : 15 : scan->rs_base.rs_flags |= SO_ALLOW_STRAT;
1263 : : else
2354 andres@anarazel.de 1264 :UBC 0 : scan->rs_base.rs_flags &= ~SO_ALLOW_STRAT;
1265 : :
2354 andres@anarazel.de 1266 [ + + ]:CBC 15 : if (allow_sync)
1267 : 6 : scan->rs_base.rs_flags |= SO_ALLOW_SYNC;
1268 : : else
1269 : 9 : scan->rs_base.rs_flags &= ~SO_ALLOW_SYNC;
1270 : :
1271 [ + - + - ]: 15 : if (allow_pagemode && scan->rs_base.rs_snapshot &&
1272 [ - + - - ]: 15 : IsMVCCSnapshot(scan->rs_base.rs_snapshot))
1273 : 15 : scan->rs_base.rs_flags |= SO_ALLOW_PAGEMODE;
1274 : : else
2354 andres@anarazel.de 1275 :UBC 0 : scan->rs_base.rs_flags &= ~SO_ALLOW_PAGEMODE;
1276 : : }
1277 : :
1278 : : /*
1279 : : * unpin scan buffers
1280 : : */
8907 tgl@sss.pgh.pa.us 1281 [ + + ]:CBC 622473 : if (BufferIsValid(scan->rs_cbuf))
1282 : : {
1283 : 1853 : ReleaseBuffer(scan->rs_cbuf);
227 melanieplageman@gmai 1284 : 1853 : scan->rs_cbuf = InvalidBuffer;
1285 : : }
1286 : :
1287 : : /*
1288 : : * SO_TYPE_BITMAPSCAN would be cleaned up here, but it does not hold any
1289 : : * additional data vs a normal HeapScan
1290 : : */
1291 : :
1292 : : /*
1293 : : * The read stream is reset on rescan. This must be done before
1294 : : * initscan(), as some state referred to by read_stream_reset() is reset
1295 : : * in initscan().
1296 : : */
568 tmunro@postgresql.or 1297 [ + + ]: 622473 : if (scan->rs_read_stream)
1298 : 622455 : read_stream_reset(scan->rs_read_stream);
1299 : :
1300 : : /*
1301 : : * reinitialize scan descriptor
1302 : : */
5984 tgl@sss.pgh.pa.us 1303 : 622473 : initscan(scan, key, true);
10703 scrappy@hub.org 1304 : 622473 : }
1305 : :
1306 : : void
2423 andres@anarazel.de 1307 : 360015 : heap_endscan(TableScanDesc sscan)
1308 : : {
1309 : 360015 : HeapScanDesc scan = (HeapScanDesc) sscan;
1310 : :
1311 : : /* Note: no locking manipulations needed */
1312 : :
1313 : : /*
1314 : : * unpin scan buffers
1315 : : */
8907 tgl@sss.pgh.pa.us 1316 [ + + ]: 360015 : if (BufferIsValid(scan->rs_cbuf))
1317 : 149616 : ReleaseBuffer(scan->rs_cbuf);
1318 : :
1319 : : /*
1320 : : * Must free the read stream before freeing the BufferAccessStrategy.
1321 : : */
568 tmunro@postgresql.or 1322 [ + + ]: 360015 : if (scan->rs_read_stream)
1323 : 350857 : read_stream_end(scan->rs_read_stream);
1324 : :
1325 : : /*
1326 : : * decrement relation reference count and free scan descriptor storage
1327 : : */
2423 andres@anarazel.de 1328 : 360015 : RelationDecrementReferenceCount(scan->rs_base.rs_rd);
1329 : :
1330 [ + + ]: 360015 : if (scan->rs_base.rs_key)
1331 : 205784 : pfree(scan->rs_base.rs_key);
1332 : :
6726 tgl@sss.pgh.pa.us 1333 [ + + ]: 360015 : if (scan->rs_strategy != NULL)
1334 : 11893 : FreeAccessStrategy(scan->rs_strategy);
1335 : :
1673 drowley@postgresql.o 1336 [ + + ]: 360015 : if (scan->rs_parallelworkerdata != NULL)
1337 : 1977 : pfree(scan->rs_parallelworkerdata);
1338 : :
2354 andres@anarazel.de 1339 [ + + ]: 360015 : if (scan->rs_base.rs_flags & SO_TEMP_SNAPSHOT)
2423 1340 : 30696 : UnregisterSnapshot(scan->rs_base.rs_snapshot);
1341 : :
9537 tgl@sss.pgh.pa.us 1342 : 360015 : pfree(scan);
10703 scrappy@hub.org 1343 : 360015 : }
1344 : :
1345 : : HeapTuple
2423 andres@anarazel.de 1346 : 9083764 : heap_getnext(TableScanDesc sscan, ScanDirection direction)
1347 : : {
1348 : 9083764 : HeapScanDesc scan = (HeapScanDesc) sscan;
1349 : :
1350 : : /*
1351 : : * This is still widely used directly, without going through table AM, so
1352 : : * add a safety check. It's possible we should, at a later point,
1353 : : * downgrade this to an assert. The reason for checking the AM routine,
1354 : : * rather than the AM oid, is that this allows to write regression tests
1355 : : * that create another AM reusing the heap handler.
1356 : : */
1357 [ - + ]: 9083764 : if (unlikely(sscan->rs_rd->rd_tableam != GetHeapamTableAmRoutine()))
2423 andres@anarazel.de 1358 [ # # ]:UBC 0 : ereport(ERROR,
1359 : : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1360 : : errmsg_internal("only heap AM is supported")));
1361 : :
1362 : : /*
1363 : : * We don't expect direct calls to heap_getnext with valid CheckXidAlive
1364 : : * for catalog or regular tables. See detailed comments in xact.c where
1365 : : * these variables are declared. Normally we have such a check at tableam
1366 : : * level API but this is called from many places so we need to ensure it
1367 : : * here.
1368 : : */
1907 akapila@postgresql.o 1369 [ - + - - :CBC 9083764 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
- + ]
1907 akapila@postgresql.o 1370 [ # # ]:UBC 0 : elog(ERROR, "unexpected heap_getnext call during logical decoding");
1371 : :
1372 : : /* Note: no locking manipulations needed */
1373 : :
2354 andres@anarazel.de 1374 [ + + ]:CBC 9083764 : if (scan->rs_base.rs_flags & SO_ALLOW_PAGEMODE)
7189 neilc@samurai.com 1375 : 1715678 : heapgettup_pagemode(scan, direction,
2423 andres@anarazel.de 1376 : 1715678 : scan->rs_base.rs_nkeys, scan->rs_base.rs_key);
1377 : : else
1378 : 7368086 : heapgettup(scan, direction,
1379 : 7368086 : scan->rs_base.rs_nkeys, scan->rs_base.rs_key);
1380 : :
7276 tgl@sss.pgh.pa.us 1381 [ + + ]: 9083764 : if (scan->rs_ctup.t_data == NULL)
8562 1382 : 56926 : return NULL;
1383 : :
1384 : : /*
1385 : : * if we get here it means we have a new current scan tuple, so point to
1386 : : * the proper return buffer and return the tuple.
1387 : : */
1388 : :
2423 andres@anarazel.de 1389 [ - + - - : 9026838 : pgstat_count_heap_getnext(scan->rs_base.rs_rd);
+ - ]
1390 : :
1391 : 9026838 : return &scan->rs_ctup;
1392 : : }
1393 : :
1394 : : bool
1395 : 47209017 : heap_getnextslot(TableScanDesc sscan, ScanDirection direction, TupleTableSlot *slot)
1396 : : {
1397 : 47209017 : HeapScanDesc scan = (HeapScanDesc) sscan;
1398 : :
1399 : : /* Note: no locking manipulations needed */
1400 : :
2354 1401 [ + + ]: 47209017 : if (sscan->rs_flags & SO_ALLOW_PAGEMODE)
1402 : 46726500 : heapgettup_pagemode(scan, direction, sscan->rs_nkeys, sscan->rs_key);
1403 : : else
1404 : 482517 : heapgettup(scan, direction, sscan->rs_nkeys, sscan->rs_key);
1405 : :
2423 1406 [ + + ]: 47208990 : if (scan->rs_ctup.t_data == NULL)
1407 : : {
1408 : 754923 : ExecClearTuple(slot);
1409 : 754923 : return false;
1410 : : }
1411 : :
1412 : : /*
1413 : : * if we get here it means we have a new current scan tuple, so point to
1414 : : * the proper return buffer and return the tuple.
1415 : : */
1416 : :
1417 [ + + - + : 46454067 : pgstat_count_heap_getnext(scan->rs_base.rs_rd);
+ + ]
1418 : :
1419 : 46454067 : ExecStoreBufferHeapTuple(&scan->rs_ctup, slot,
1420 : : scan->rs_cbuf);
1421 : 46454067 : return true;
1422 : : }
1423 : :
1424 : : void
1704 drowley@postgresql.o 1425 : 958 : heap_set_tidrange(TableScanDesc sscan, ItemPointer mintid,
1426 : : ItemPointer maxtid)
1427 : : {
1428 : 958 : HeapScanDesc scan = (HeapScanDesc) sscan;
1429 : : BlockNumber startBlk;
1430 : : BlockNumber numBlks;
1431 : : ItemPointerData highestItem;
1432 : : ItemPointerData lowestItem;
1433 : :
1434 : : /*
1435 : : * For relations without any pages, we can simply leave the TID range
1436 : : * unset. There will be no tuples to scan, therefore no tuples outside
1437 : : * the given TID range.
1438 : : */
1439 [ + + ]: 958 : if (scan->rs_nblocks == 0)
1440 : 24 : return;
1441 : :
1442 : : /*
1443 : : * Set up some ItemPointers which point to the first and last possible
1444 : : * tuples in the heap.
1445 : : */
1446 : 952 : ItemPointerSet(&highestItem, scan->rs_nblocks - 1, MaxOffsetNumber);
1447 : 952 : ItemPointerSet(&lowestItem, 0, FirstOffsetNumber);
1448 : :
1449 : : /*
1450 : : * If the given maximum TID is below the highest possible TID in the
1451 : : * relation, then restrict the range to that, otherwise we scan to the end
1452 : : * of the relation.
1453 : : */
1454 [ + + ]: 952 : if (ItemPointerCompare(maxtid, &highestItem) < 0)
1455 : 68 : ItemPointerCopy(maxtid, &highestItem);
1456 : :
1457 : : /*
1458 : : * If the given minimum TID is above the lowest possible TID in the
1459 : : * relation, then restrict the range to only scan for TIDs above that.
1460 : : */
1461 [ + + ]: 952 : if (ItemPointerCompare(mintid, &lowestItem) > 0)
1462 : 881 : ItemPointerCopy(mintid, &lowestItem);
1463 : :
1464 : : /*
1465 : : * Check for an empty range and protect from would be negative results
1466 : : * from the numBlks calculation below.
1467 : : */
1468 [ + + ]: 952 : if (ItemPointerCompare(&highestItem, &lowestItem) < 0)
1469 : : {
1470 : : /* Set an empty range of blocks to scan */
1471 : 18 : heap_setscanlimits(sscan, 0, 0);
1472 : 18 : return;
1473 : : }
1474 : :
1475 : : /*
1476 : : * Calculate the first block and the number of blocks we must scan. We
1477 : : * could be more aggressive here and perform some more validation to try
1478 : : * and further narrow the scope of blocks to scan by checking if the
1479 : : * lowestItem has an offset above MaxOffsetNumber. In this case, we could
1480 : : * advance startBlk by one. Likewise, if highestItem has an offset of 0
1481 : : * we could scan one fewer blocks. However, such an optimization does not
1482 : : * seem worth troubling over, currently.
1483 : : */
1484 : 934 : startBlk = ItemPointerGetBlockNumberNoCheck(&lowestItem);
1485 : :
1486 : 934 : numBlks = ItemPointerGetBlockNumberNoCheck(&highestItem) -
1487 : 934 : ItemPointerGetBlockNumberNoCheck(&lowestItem) + 1;
1488 : :
1489 : : /* Set the start block and number of blocks to scan */
1490 : 934 : heap_setscanlimits(sscan, startBlk, numBlks);
1491 : :
1492 : : /* Finally, set the TID range in sscan */
368 melanieplageman@gmai 1493 : 934 : ItemPointerCopy(&lowestItem, &sscan->st.tidrange.rs_mintid);
1494 : 934 : ItemPointerCopy(&highestItem, &sscan->st.tidrange.rs_maxtid);
1495 : : }
1496 : :
1497 : : bool
1704 drowley@postgresql.o 1498 : 3847 : heap_getnextslot_tidrange(TableScanDesc sscan, ScanDirection direction,
1499 : : TupleTableSlot *slot)
1500 : : {
1501 : 3847 : HeapScanDesc scan = (HeapScanDesc) sscan;
368 melanieplageman@gmai 1502 : 3847 : ItemPointer mintid = &sscan->st.tidrange.rs_mintid;
1503 : 3847 : ItemPointer maxtid = &sscan->st.tidrange.rs_maxtid;
1504 : :
1505 : : /* Note: no locking manipulations needed */
1506 : : for (;;)
1507 : : {
1704 drowley@postgresql.o 1508 [ + - ]: 3940 : if (sscan->rs_flags & SO_ALLOW_PAGEMODE)
1509 : 3940 : heapgettup_pagemode(scan, direction, sscan->rs_nkeys, sscan->rs_key);
1510 : : else
1704 drowley@postgresql.o 1511 :UBC 0 : heapgettup(scan, direction, sscan->rs_nkeys, sscan->rs_key);
1512 : :
1704 drowley@postgresql.o 1513 [ + + ]:CBC 3934 : if (scan->rs_ctup.t_data == NULL)
1514 : : {
1515 : 47 : ExecClearTuple(slot);
1516 : 47 : return false;
1517 : : }
1518 : :
1519 : : /*
1520 : : * heap_set_tidrange will have used heap_setscanlimits to limit the
1521 : : * range of pages we scan to only ones that can contain the TID range
1522 : : * we're scanning for. Here we must filter out any tuples from these
1523 : : * pages that are outside of that range.
1524 : : */
1525 [ + + ]: 3887 : if (ItemPointerCompare(&scan->rs_ctup.t_self, mintid) < 0)
1526 : : {
1527 : 93 : ExecClearTuple(slot);
1528 : :
1529 : : /*
1530 : : * When scanning backwards, the TIDs will be in descending order.
1531 : : * Future tuples in this direction will be lower still, so we can
1532 : : * just return false to indicate there will be no more tuples.
1533 : : */
1534 [ - + ]: 93 : if (ScanDirectionIsBackward(direction))
1704 drowley@postgresql.o 1535 :UBC 0 : return false;
1536 : :
1704 drowley@postgresql.o 1537 :CBC 93 : continue;
1538 : : }
1539 : :
1540 : : /*
1541 : : * Likewise for the final page, we must filter out TIDs greater than
1542 : : * maxtid.
1543 : : */
1544 [ + + ]: 3794 : if (ItemPointerCompare(&scan->rs_ctup.t_self, maxtid) > 0)
1545 : : {
1546 : 38 : ExecClearTuple(slot);
1547 : :
1548 : : /*
1549 : : * When scanning forward, the TIDs will be in ascending order.
1550 : : * Future tuples in this direction will be higher still, so we can
1551 : : * just return false to indicate there will be no more tuples.
1552 : : */
1553 [ + - ]: 38 : if (ScanDirectionIsForward(direction))
1554 : 38 : return false;
1704 drowley@postgresql.o 1555 :UBC 0 : continue;
1556 : : }
1557 : :
1704 drowley@postgresql.o 1558 :CBC 3756 : break;
1559 : : }
1560 : :
1561 : : /*
1562 : : * if we get here it means we have a new current scan tuple, so point to
1563 : : * the proper return buffer and return the tuple.
1564 : : */
1565 [ - + - - : 3756 : pgstat_count_heap_getnext(scan->rs_base.rs_rd);
+ - ]
1566 : :
1567 : 3756 : ExecStoreBufferHeapTuple(&scan->rs_ctup, slot, scan->rs_cbuf);
1568 : 3756 : return true;
1569 : : }
1570 : :
1571 : : /*
1572 : : * heap_fetch - retrieve tuple with given tid
1573 : : *
1574 : : * On entry, tuple->t_self is the TID to fetch. We pin the buffer holding
1575 : : * the tuple, fill in the remaining fields of *tuple, and check the tuple
1576 : : * against the specified snapshot.
1577 : : *
1578 : : * If successful (tuple found and passes snapshot time qual), then *userbuf
1579 : : * is set to the buffer holding the tuple and true is returned. The caller
1580 : : * must unpin the buffer when done with the tuple.
1581 : : *
1582 : : * If the tuple is not found (ie, item number references a deleted slot),
1583 : : * then tuple->t_data is set to NULL, *userbuf is set to InvalidBuffer,
1584 : : * and false is returned.
1585 : : *
1586 : : * If the tuple is found but fails the time qual check, then the behavior
1587 : : * depends on the keep_buf parameter. If keep_buf is false, the results
1588 : : * are the same as for the tuple-not-found case. If keep_buf is true,
1589 : : * then tuple->t_data and *userbuf are returned as for the success case,
1590 : : * and again the caller must unpin the buffer; but false is returned.
1591 : : *
1592 : : * heap_fetch does not follow HOT chains: only the exact TID requested will
1593 : : * be fetched.
1594 : : *
1595 : : * It is somewhat inconsistent that we ereport() on invalid block number but
1596 : : * return false on invalid item number. There are a couple of reasons though.
1597 : : * One is that the caller can relatively easily check the block number for
1598 : : * validity, but cannot check the item number without reading the page
1599 : : * himself. Another is that when we are following a t_ctid link, we can be
1600 : : * reasonably confident that the page number is valid (since VACUUM shouldn't
1601 : : * truncate off the destination page without having killed the referencing
1602 : : * tuple first), but the item number might well not be good.
1603 : : */
1604 : : bool
10703 scrappy@hub.org 1605 : 178205 : heap_fetch(Relation relation,
1606 : : Snapshot snapshot,
1607 : : HeapTuple tuple,
1608 : : Buffer *userbuf,
1609 : : bool keep_buf)
1610 : : {
8558 tgl@sss.pgh.pa.us 1611 : 178205 : ItemPointer tid = &(tuple->t_self);
1612 : : ItemId lp;
1613 : : Buffer buffer;
1614 : : Page page;
1615 : : OffsetNumber offnum;
1616 : : bool valid;
1617 : :
1618 : : /*
1619 : : * Fetch and pin the appropriate page of the relation.
1620 : : */
6417 1621 : 178205 : buffer = ReadBuffer(relation, ItemPointerGetBlockNumber(tid));
1622 : :
1623 : : /*
1624 : : * Need share lock on buffer to examine tuple commit status.
1625 : : */
9814 vadim4o@yahoo.com 1626 : 178196 : LockBuffer(buffer, BUFFER_LOCK_SHARE);
3478 kgrittn@postgresql.o 1627 : 178196 : page = BufferGetPage(buffer);
1628 : :
1629 : : /*
1630 : : * We'd better check for out-of-range offnum in case of VACUUM since the
1631 : : * TID was obtained.
1632 : : */
10278 bruce@momjian.us 1633 : 178196 : offnum = ItemPointerGetOffsetNumber(tid);
6316 tgl@sss.pgh.pa.us 1634 [ + - + + ]: 178196 : if (offnum < FirstOffsetNumber || offnum > PageGetMaxOffsetNumber(page))
1635 : : {
7520 1636 : 3 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
2411 andres@anarazel.de 1637 : 3 : ReleaseBuffer(buffer);
1638 : 3 : *userbuf = InvalidBuffer;
7520 tgl@sss.pgh.pa.us 1639 : 3 : tuple->t_data = NULL;
1640 : 3 : return false;
1641 : : }
1642 : :
1643 : : /*
1644 : : * get the item line pointer corresponding to the requested tid
1645 : : */
6316 1646 : 178193 : lp = PageGetItemId(page, offnum);
1647 : :
1648 : : /*
1649 : : * Must check for deleted tuple.
1650 : : */
6621 1651 [ + + ]: 178193 : if (!ItemIdIsNormal(lp))
1652 : : {
9247 vadim4o@yahoo.com 1653 : 338 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
2411 andres@anarazel.de 1654 : 338 : ReleaseBuffer(buffer);
1655 : 338 : *userbuf = InvalidBuffer;
8558 tgl@sss.pgh.pa.us 1656 : 338 : tuple->t_data = NULL;
1657 : 338 : return false;
1658 : : }
1659 : :
1660 : : /*
1661 : : * fill in *tuple fields
1662 : : */
6316 1663 : 177855 : tuple->t_data = (HeapTupleHeader) PageGetItem(page, lp);
9832 vadim4o@yahoo.com 1664 : 177855 : tuple->t_len = ItemIdGetLength(lp);
7374 tgl@sss.pgh.pa.us 1665 : 177855 : tuple->t_tableOid = RelationGetRelid(relation);
1666 : :
1667 : : /*
1668 : : * check tuple visibility, then release lock
1669 : : */
7276 1670 : 177855 : valid = HeapTupleSatisfiesVisibility(tuple, snapshot, buffer);
1671 : :
5377 heikki.linnakangas@i 1672 [ + + ]: 177855 : if (valid)
2100 tmunro@postgresql.or 1673 : 177800 : PredicateLockTID(relation, &(tuple->t_self), snapshot,
1674 : 177800 : HeapTupleHeaderGetXmin(tuple->t_data));
1675 : :
1676 : 177855 : HeapCheckForSerializableConflictOut(valid, relation, tuple, buffer, snapshot);
1677 : :
5352 heikki.linnakangas@i 1678 : 177855 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
1679 : :
8558 tgl@sss.pgh.pa.us 1680 [ + + ]: 177855 : if (valid)
1681 : : {
1682 : : /*
1683 : : * All checks passed, so return the tuple as valid. Caller is now
1684 : : * responsible for releasing the buffer.
1685 : : */
9531 1686 : 177800 : *userbuf = buffer;
1687 : :
8558 1688 : 177800 : return true;
1689 : : }
1690 : :
1691 : : /* Tuple failed time qual, but maybe caller wants to see it anyway. */
1294 1692 [ + + ]: 55 : if (keep_buf)
1693 : 34 : *userbuf = buffer;
1694 : : else
1695 : : {
1696 : 21 : ReleaseBuffer(buffer);
1697 : 21 : *userbuf = InvalidBuffer;
1698 : 21 : tuple->t_data = NULL;
1699 : : }
1700 : :
8558 1701 : 55 : return false;
1702 : : }
1703 : :
1704 : : /*
1705 : : * heap_hot_search_buffer - search HOT chain for tuple satisfying snapshot
1706 : : *
1707 : : * On entry, *tid is the TID of a tuple (either a simple tuple, or the root
1708 : : * of a HOT chain), and buffer is the buffer holding this tuple. We search
1709 : : * for the first chain member satisfying the given snapshot. If one is
1710 : : * found, we update *tid to reference that tuple's offset number, and
1711 : : * return true. If no match, return false without modifying *tid.
1712 : : *
1713 : : * heapTuple is a caller-supplied buffer. When a match is found, we return
1714 : : * the tuple here, in addition to updating *tid. If no match is found, the
1715 : : * contents of this buffer on return are undefined.
1716 : : *
1717 : : * If all_dead is not NULL, we check non-visible tuples to see if they are
1718 : : * globally dead; *all_dead is set true if all members of the HOT chain
1719 : : * are vacuumable, false if not.
1720 : : *
1721 : : * Unlike heap_fetch, the caller must already have pin and (at least) share
1722 : : * lock on the buffer; it is still pinned/locked at exit.
1723 : : */
1724 : : bool
5377 heikki.linnakangas@i 1725 : 20995969 : heap_hot_search_buffer(ItemPointer tid, Relation relation, Buffer buffer,
1726 : : Snapshot snapshot, HeapTuple heapTuple,
1727 : : bool *all_dead, bool first_call)
1728 : : {
1077 peter@eisentraut.org 1729 : 20995969 : Page page = BufferGetPage(buffer);
6613 tgl@sss.pgh.pa.us 1730 : 20995969 : TransactionId prev_xmax = InvalidTransactionId;
1731 : : BlockNumber blkno;
1732 : : OffsetNumber offnum;
1733 : : bool at_chain_start;
1734 : : bool valid;
1735 : : bool skip;
1903 andres@anarazel.de 1736 : 20995969 : GlobalVisState *vistest = NULL;
1737 : :
1738 : : /* If this is not the first call, previous call returned a (live!) tuple */
6613 tgl@sss.pgh.pa.us 1739 [ + + ]: 20995969 : if (all_dead)
5237 rhaas@postgresql.org 1740 : 17793558 : *all_dead = first_call;
1741 : :
2274 heikki.linnakangas@i 1742 : 20995969 : blkno = ItemPointerGetBlockNumber(tid);
6613 tgl@sss.pgh.pa.us 1743 : 20995969 : offnum = ItemPointerGetOffsetNumber(tid);
5237 rhaas@postgresql.org 1744 : 20995969 : at_chain_start = first_call;
1745 : 20995969 : skip = !first_call;
1746 : :
1747 : : /* XXX: we should assert that a snapshot is pushed or registered */
1903 andres@anarazel.de 1748 [ - + ]: 20995969 : Assert(TransactionIdIsValid(RecentXmin));
2274 heikki.linnakangas@i 1749 [ + - ]: 20995969 : Assert(BufferGetBlockNumber(buffer) == blkno);
1750 : :
1751 : : /* Scan through possible multiple members of HOT-chain */
1752 : : for (;;)
6613 tgl@sss.pgh.pa.us 1753 : 1464437 : {
1754 : : ItemId lp;
1755 : :
1756 : : /* check for bogus TID */
1077 peter@eisentraut.org 1757 [ + - + - ]: 22460406 : if (offnum < FirstOffsetNumber || offnum > PageGetMaxOffsetNumber(page))
1758 : : break;
1759 : :
1760 : 22460406 : lp = PageGetItemId(page, offnum);
1761 : :
1762 : : /* check for unused, dead, or redirected items */
6613 tgl@sss.pgh.pa.us 1763 [ + + ]: 22460406 : if (!ItemIdIsNormal(lp))
1764 : : {
1765 : : /* We should only see a redirect at start of chain */
1766 [ + + + - ]: 751904 : if (ItemIdIsRedirected(lp) && at_chain_start)
1767 : : {
1768 : : /* Follow the redirect */
1769 : 409308 : offnum = ItemIdGetRedirect(lp);
1770 : 409308 : at_chain_start = false;
1771 : 409308 : continue;
1772 : : }
1773 : : /* else must be end of chain */
1774 : 342596 : break;
1775 : : }
1776 : :
1777 : : /*
1778 : : * Update heapTuple to point to the element of the HOT chain we're
1779 : : * currently investigating. Having t_self set correctly is important
1780 : : * because the SSI checks and the *Satisfies routine for historical
1781 : : * MVCC snapshots need the correct tid to decide about the visibility.
1782 : : */
1077 peter@eisentraut.org 1783 : 21708502 : heapTuple->t_data = (HeapTupleHeader) PageGetItem(page, lp);
5237 rhaas@postgresql.org 1784 : 21708502 : heapTuple->t_len = ItemIdGetLength(lp);
4481 1785 : 21708502 : heapTuple->t_tableOid = RelationGetRelid(relation);
2274 heikki.linnakangas@i 1786 : 21708502 : ItemPointerSet(&heapTuple->t_self, blkno, offnum);
1787 : :
1788 : : /*
1789 : : * Shouldn't see a HEAP_ONLY tuple at chain start.
1790 : : */
5237 rhaas@postgresql.org 1791 [ + + - + ]: 21708502 : if (at_chain_start && HeapTupleIsHeapOnly(heapTuple))
6613 tgl@sss.pgh.pa.us 1792 :UBC 0 : break;
1793 : :
1794 : : /*
1795 : : * The xmin should match the previous xmax value, else chain is
1796 : : * broken.
1797 : : */
6613 tgl@sss.pgh.pa.us 1798 [ + + - + ]:CBC 22763631 : if (TransactionIdIsValid(prev_xmax) &&
2917 alvherre@alvh.no-ip. 1799 : 1055129 : !TransactionIdEquals(prev_xmax,
1800 : : HeapTupleHeaderGetXmin(heapTuple->t_data)))
6613 tgl@sss.pgh.pa.us 1801 :UBC 0 : break;
1802 : :
1803 : : /*
1804 : : * When first_call is true (and thus, skip is initially false) we'll
1805 : : * return the first tuple we find. But on later passes, heapTuple
1806 : : * will initially be pointing to the tuple we returned last time.
1807 : : * Returning it again would be incorrect (and would loop forever), so
1808 : : * we skip it and return the next match we find.
1809 : : */
5237 rhaas@postgresql.org 1810 [ + + ]:CBC 21708502 : if (!skip)
1811 : : {
1812 : : /* If it's visible per the snapshot, we must return it */
1813 : 21622726 : valid = HeapTupleSatisfiesVisibility(heapTuple, snapshot, buffer);
2100 tmunro@postgresql.or 1814 : 21622726 : HeapCheckForSerializableConflictOut(valid, relation, heapTuple,
1815 : : buffer, snapshot);
1816 : :
5237 rhaas@postgresql.org 1817 [ + + ]: 21622721 : if (valid)
1818 : : {
1819 : 14457707 : ItemPointerSetOffsetNumber(tid, offnum);
2100 tmunro@postgresql.or 1820 : 14457707 : PredicateLockTID(relation, &heapTuple->t_self, snapshot,
1821 : 14457707 : HeapTupleHeaderGetXmin(heapTuple->t_data));
5237 rhaas@postgresql.org 1822 [ + + ]: 14457707 : if (all_dead)
1823 : 11528509 : *all_dead = false;
1824 : 14457707 : return true;
1825 : : }
1826 : : }
1827 : 7250790 : skip = false;
1828 : :
1829 : : /*
1830 : : * If we can't see it, maybe no one else can either. At caller
1831 : : * request, check whether all chain members are dead to all
1832 : : * transactions.
1833 : : *
1834 : : * Note: if you change the criterion here for what is "dead", fix the
1835 : : * planner's get_actual_variable_range() function to match.
1836 : : */
1903 andres@anarazel.de 1837 [ + + + + ]: 7250790 : if (all_dead && *all_dead)
1838 : : {
1839 [ + + ]: 6425643 : if (!vistest)
1840 : 6301498 : vistest = GlobalVisTestFor(relation);
1841 : :
1842 [ + + ]: 6425643 : if (!HeapTupleIsSurelyDead(heapTuple, vistest))
1843 : 6066091 : *all_dead = false;
1844 : : }
1845 : :
1846 : : /*
1847 : : * Check to see if HOT chain continues past this tuple; if so fetch
1848 : : * the next offnum and loop around.
1849 : : */
5237 rhaas@postgresql.org 1850 [ + + ]: 7250790 : if (HeapTupleIsHotUpdated(heapTuple))
1851 : : {
1852 [ - + ]: 1055129 : Assert(ItemPointerGetBlockNumber(&heapTuple->t_data->t_ctid) ==
1853 : : blkno);
1854 : 1055129 : offnum = ItemPointerGetOffsetNumber(&heapTuple->t_data->t_ctid);
6613 tgl@sss.pgh.pa.us 1855 : 1055129 : at_chain_start = false;
4661 alvherre@alvh.no-ip. 1856 : 1055129 : prev_xmax = HeapTupleHeaderGetUpdateXid(heapTuple->t_data);
1857 : : }
1858 : : else
6557 bruce@momjian.us 1859 : 6195661 : break; /* end of chain */
1860 : : }
1861 : :
5265 heikki.linnakangas@i 1862 : 6538257 : return false;
1863 : : }
1864 : :
1865 : : /*
1866 : : * heap_get_latest_tid - get the latest tid of a specified tuple
1867 : : *
1868 : : * Actually, this gets the latest version that is visible according to the
1869 : : * scan's snapshot. Create a scan using SnapshotDirty to get the very latest,
1870 : : * possibly uncommitted version.
1871 : : *
1872 : : * *tid is both an input and an output parameter: it is updated to
1873 : : * show the latest version of the row. Note that it will not be changed
1874 : : * if no version of the row passes the snapshot test.
1875 : : */
1876 : : void
2356 andres@anarazel.de 1877 : 150 : heap_get_latest_tid(TableScanDesc sscan,
1878 : : ItemPointer tid)
1879 : : {
2351 tgl@sss.pgh.pa.us 1880 : 150 : Relation relation = sscan->rs_rd;
1881 : 150 : Snapshot snapshot = sscan->rs_snapshot;
1882 : : ItemPointerData ctid;
1883 : : TransactionId priorXmax;
1884 : :
1885 : : /*
1886 : : * table_tuple_get_latest_tid() verified that the passed in tid is valid.
1887 : : * Assume that t_ctid links are valid however - there shouldn't be invalid
1888 : : * ones in the table.
1889 : : */
2356 andres@anarazel.de 1890 [ - + ]: 150 : Assert(ItemPointerIsValid(tid));
1891 : :
1892 : : /*
1893 : : * Loop to chase down t_ctid links. At top of loop, ctid is the tuple we
1894 : : * need to examine, and *tid is the TID we will return if ctid turns out
1895 : : * to be bogus.
1896 : : *
1897 : : * Note that we will loop until we reach the end of the t_ctid chain.
1898 : : * Depending on the snapshot passed, there might be at most one visible
1899 : : * version of the row, but we don't try to optimize for that.
1900 : : */
7374 tgl@sss.pgh.pa.us 1901 : 150 : ctid = *tid;
1902 : 150 : priorXmax = InvalidTransactionId; /* cannot check first XMIN */
1903 : : for (;;)
1904 : 45 : {
1905 : : Buffer buffer;
1906 : : Page page;
1907 : : OffsetNumber offnum;
1908 : : ItemId lp;
1909 : : HeapTupleData tp;
1910 : : bool valid;
1911 : :
1912 : : /*
1913 : : * Read, pin, and lock the page.
1914 : : */
1915 : 195 : buffer = ReadBuffer(relation, ItemPointerGetBlockNumber(&ctid));
1916 : 195 : LockBuffer(buffer, BUFFER_LOCK_SHARE);
3478 kgrittn@postgresql.o 1917 : 195 : page = BufferGetPage(buffer);
1918 : :
1919 : : /*
1920 : : * Check for bogus item number. This is not treated as an error
1921 : : * condition because it can happen while following a t_ctid link. We
1922 : : * just assume that the prior tid is OK and return it unchanged.
1923 : : */
7374 tgl@sss.pgh.pa.us 1924 : 195 : offnum = ItemPointerGetOffsetNumber(&ctid);
6316 1925 [ + - - + ]: 195 : if (offnum < FirstOffsetNumber || offnum > PageGetMaxOffsetNumber(page))
1926 : : {
7151 tgl@sss.pgh.pa.us 1927 :UBC 0 : UnlockReleaseBuffer(buffer);
7374 1928 : 0 : break;
1929 : : }
6316 tgl@sss.pgh.pa.us 1930 :CBC 195 : lp = PageGetItemId(page, offnum);
6621 1931 [ - + ]: 195 : if (!ItemIdIsNormal(lp))
1932 : : {
7151 tgl@sss.pgh.pa.us 1933 :UBC 0 : UnlockReleaseBuffer(buffer);
7374 1934 : 0 : break;
1935 : : }
1936 : :
1937 : : /* OK to access the tuple */
7374 tgl@sss.pgh.pa.us 1938 :CBC 195 : tp.t_self = ctid;
6316 1939 : 195 : tp.t_data = (HeapTupleHeader) PageGetItem(page, lp);
7374 1940 : 195 : tp.t_len = ItemIdGetLength(lp);
4481 rhaas@postgresql.org 1941 : 195 : tp.t_tableOid = RelationGetRelid(relation);
1942 : :
1943 : : /*
1944 : : * After following a t_ctid link, we might arrive at an unrelated
1945 : : * tuple. Check for XMIN match.
1946 : : */
7374 tgl@sss.pgh.pa.us 1947 [ + + - + ]: 240 : if (TransactionIdIsValid(priorXmax) &&
2917 alvherre@alvh.no-ip. 1948 : 45 : !TransactionIdEquals(priorXmax, HeapTupleHeaderGetXmin(tp.t_data)))
1949 : : {
7151 tgl@sss.pgh.pa.us 1950 :UBC 0 : UnlockReleaseBuffer(buffer);
7374 1951 : 0 : break;
1952 : : }
1953 : :
1954 : : /*
1955 : : * Check tuple visibility; if visible, set it as the new result
1956 : : * candidate.
1957 : : */
7276 tgl@sss.pgh.pa.us 1958 :CBC 195 : valid = HeapTupleSatisfiesVisibility(&tp, snapshot, buffer);
2100 tmunro@postgresql.or 1959 : 195 : HeapCheckForSerializableConflictOut(valid, relation, &tp, buffer, snapshot);
7374 tgl@sss.pgh.pa.us 1960 [ + + ]: 195 : if (valid)
1961 : 138 : *tid = ctid;
1962 : :
1963 : : /*
1964 : : * If there's a valid t_ctid link, follow it, else we're done.
1965 : : */
4661 alvherre@alvh.no-ip. 1966 [ + + + + ]: 276 : if ((tp.t_data->t_infomask & HEAP_XMAX_INVALID) ||
1967 [ + - ]: 138 : HeapTupleHeaderIsOnlyLocked(tp.t_data) ||
2761 andres@anarazel.de 1968 [ + + ]: 114 : HeapTupleHeaderIndicatesMovedPartitions(tp.t_data) ||
7374 tgl@sss.pgh.pa.us 1969 : 57 : ItemPointerEquals(&tp.t_self, &tp.t_data->t_ctid))
1970 : : {
7151 1971 : 150 : UnlockReleaseBuffer(buffer);
7374 1972 : 150 : break;
1973 : : }
1974 : :
1975 : 45 : ctid = tp.t_data->t_ctid;
4661 alvherre@alvh.no-ip. 1976 : 45 : priorXmax = HeapTupleHeaderGetUpdateXid(tp.t_data);
7151 tgl@sss.pgh.pa.us 1977 : 45 : UnlockReleaseBuffer(buffer);
1978 : : } /* end of loop */
9514 inoue@tpf.co.jp 1979 : 150 : }
1980 : :
1981 : :
1982 : : /*
1983 : : * UpdateXmaxHintBits - update tuple hint bits after xmax transaction ends
1984 : : *
1985 : : * This is called after we have waited for the XMAX transaction to terminate.
1986 : : * If the transaction aborted, we guarantee the XMAX_INVALID hint bit will
1987 : : * be set on exit. If the transaction committed, we set the XMAX_COMMITTED
1988 : : * hint bit if possible --- but beware that that may not yet be possible,
1989 : : * if the transaction committed asynchronously.
1990 : : *
1991 : : * Note that if the transaction was a locker only, we set HEAP_XMAX_INVALID
1992 : : * even if it commits.
1993 : : *
1994 : : * Hence callers should look only at XMAX_INVALID.
1995 : : *
1996 : : * Note this is not allowed for tuples whose xmax is a multixact.
1997 : : */
1998 : : static void
6650 tgl@sss.pgh.pa.us 1999 : 214 : UpdateXmaxHintBits(HeapTupleHeader tuple, Buffer buffer, TransactionId xid)
2000 : : {
4661 alvherre@alvh.no-ip. 2001 [ - + ]: 214 : Assert(TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple), xid));
2002 [ - + ]: 214 : Assert(!(tuple->t_infomask & HEAP_XMAX_IS_MULTI));
2003 : :
6650 tgl@sss.pgh.pa.us 2004 [ + - ]: 214 : if (!(tuple->t_infomask & (HEAP_XMAX_COMMITTED | HEAP_XMAX_INVALID)))
2005 : : {
4661 alvherre@alvh.no-ip. 2006 [ + + + + ]: 383 : if (!HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask) &&
2007 : 169 : TransactionIdDidCommit(xid))
6650 tgl@sss.pgh.pa.us 2008 : 142 : HeapTupleSetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
2009 : : xid);
2010 : : else
2011 : 72 : HeapTupleSetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
2012 : : InvalidTransactionId);
2013 : : }
2014 : 214 : }
2015 : :
2016 : :
2017 : : /*
2018 : : * GetBulkInsertState - prepare status object for a bulk insert
2019 : : */
2020 : : BulkInsertState
6200 2021 : 2331 : GetBulkInsertState(void)
2022 : : {
2023 : : BulkInsertState bistate;
2024 : :
2025 : 2331 : bistate = (BulkInsertState) palloc(sizeof(BulkInsertStateData));
2026 : 2331 : bistate->strategy = GetAccessStrategy(BAS_BULKWRITE);
2027 : 2331 : bistate->current_buf = InvalidBuffer;
936 andres@anarazel.de 2028 : 2331 : bistate->next_free = InvalidBlockNumber;
2029 : 2331 : bistate->last_free = InvalidBlockNumber;
806 2030 : 2331 : bistate->already_extended_by = 0;
6200 tgl@sss.pgh.pa.us 2031 : 2331 : return bistate;
2032 : : }
2033 : :
2034 : : /*
2035 : : * FreeBulkInsertState - clean up after finishing a bulk insert
2036 : : */
2037 : : void
2038 : 2189 : FreeBulkInsertState(BulkInsertState bistate)
2039 : : {
2040 [ + + ]: 2189 : if (bistate->current_buf != InvalidBuffer)
5983 bruce@momjian.us 2041 : 1756 : ReleaseBuffer(bistate->current_buf);
6200 tgl@sss.pgh.pa.us 2042 : 2189 : FreeAccessStrategy(bistate->strategy);
2043 : 2189 : pfree(bistate);
2044 : 2189 : }
2045 : :
2046 : : /*
2047 : : * ReleaseBulkInsertStatePin - release a buffer currently held in bistate
2048 : : */
2049 : : void
3199 rhaas@postgresql.org 2050 : 80758 : ReleaseBulkInsertStatePin(BulkInsertState bistate)
2051 : : {
2052 [ + + ]: 80758 : if (bistate->current_buf != InvalidBuffer)
2053 : 30021 : ReleaseBuffer(bistate->current_buf);
2054 : 80758 : bistate->current_buf = InvalidBuffer;
2055 : :
2056 : : /*
2057 : : * Despite the name, we also reset bulk relation extension state.
2058 : : * Otherwise we can end up erroring out due to looking for free space in
2059 : : * ->next_free of one partition, even though ->next_free was set when
2060 : : * extending another partition. It could obviously also be bad for
2061 : : * efficiency to look at existing blocks at offsets from another
2062 : : * partition, even if we don't error out.
2063 : : */
746 andres@anarazel.de 2064 : 80758 : bistate->next_free = InvalidBlockNumber;
2065 : 80758 : bistate->last_free = InvalidBlockNumber;
3199 rhaas@postgresql.org 2066 : 80758 : }
2067 : :
2068 : :
2069 : : /*
2070 : : * heap_insert - insert tuple into a heap
2071 : : *
2072 : : * The new tuple is stamped with current transaction ID and the specified
2073 : : * command ID.
2074 : : *
2075 : : * See table_tuple_insert for comments about most of the input flags, except
2076 : : * that this routine directly takes a tuple rather than a slot.
2077 : : *
2078 : : * There's corresponding HEAP_INSERT_ options to all the TABLE_INSERT_
2079 : : * options, and there additionally is HEAP_INSERT_SPECULATIVE which is used to
2080 : : * implement table_tuple_insert_speculative().
2081 : : *
2082 : : * On return the header fields of *tup are updated to match the stored tuple;
2083 : : * in particular tup->t_self receives the actual TID where the tuple was
2084 : : * stored. But note that any toasting of fields within the tuple data is NOT
2085 : : * reflected into *tup.
2086 : : */
2087 : : void
7435 tgl@sss.pgh.pa.us 2088 : 8416413 : heap_insert(Relation relation, HeapTuple tup, CommandId cid,
2089 : : int options, BulkInsertState bistate)
2090 : : {
7712 2091 : 8416413 : TransactionId xid = GetCurrentTransactionId();
2092 : : HeapTuple heaptup;
2093 : : Buffer buffer;
5243 rhaas@postgresql.org 2094 : 8416413 : Buffer vmbuffer = InvalidBuffer;
6173 heikki.linnakangas@i 2095 : 8416413 : bool all_visible_cleared = false;
2096 : :
2097 : : /* Cheap, simplistic check that the tuple matches the rel's rowtype. */
1632 tgl@sss.pgh.pa.us 2098 [ - + ]: 8416413 : Assert(HeapTupleHeaderGetNatts(tup->t_data) <=
2099 : : RelationGetNumberOfAttributes(relation));
2100 : :
151 nathan@postgresql.or 2101 : 8416413 : AssertHasSnapshotForToast(relation);
2102 : :
2103 : : /*
2104 : : * Fill in tuple header fields and toast the tuple if necessary.
2105 : : *
2106 : : * Note: below this point, heaptup is the data we actually intend to store
2107 : : * into the relation; tup is the caller's original untoasted data.
2108 : : */
5102 heikki.linnakangas@i 2109 : 8416413 : heaptup = heap_prepare_insert(relation, tup, xid, cid, options);
2110 : :
2111 : : /*
2112 : : * Find buffer to insert this tuple into. If the page is all visible,
2113 : : * this will also pin the requisite visibility map page.
2114 : : */
3650 kgrittn@postgresql.o 2115 : 8416413 : buffer = RelationGetBufferForTuple(relation, heaptup->t_len,
2116 : : InvalidBuffer, options, bistate,
2117 : : &vmbuffer, NULL,
2118 : : 0);
2119 : :
2120 : : /*
2121 : : * We're about to do the actual insert -- but check for conflict first, to
2122 : : * avoid possibly having to roll back work we've just done.
2123 : : *
2124 : : * This is safe without a recheck as long as there is no possibility of
2125 : : * another process scanning the page between this check and the insert
2126 : : * being visible to the scan (i.e., an exclusive buffer content lock is
2127 : : * continuously held from this point until the tuple insert is visible).
2128 : : *
2129 : : * For a heap insert, we only need to check for table-level SSI locks. Our
2130 : : * new tuple can't possibly conflict with existing tuple locks, and heap
2131 : : * page locks are only consolidated versions of tuple locks; they do not
2132 : : * lock "gaps" as index page locks do. So we don't need to specify a
2133 : : * buffer when making the call, which makes for a faster check.
2134 : : */
2100 tmunro@postgresql.or 2135 : 8416413 : CheckForSerializableConflictIn(relation, NULL, InvalidBlockNumber);
2136 : :
2137 : : /* NO EREPORT(ERROR) from here till changes are logged */
9055 tgl@sss.pgh.pa.us 2138 : 8416401 : START_CRIT_SECTION();
2139 : :
3826 andres@anarazel.de 2140 : 8416401 : RelationPutHeapTuple(relation, buffer, heaptup,
2141 : 8416401 : (options & HEAP_INSERT_SPECULATIVE) != 0);
2142 : :
1608 tomas.vondra@postgre 2143 [ + + ]: 8416401 : if (PageIsAllVisible(BufferGetPage(buffer)))
2144 : : {
6173 heikki.linnakangas@i 2145 : 7553 : all_visible_cleared = true;
3478 kgrittn@postgresql.o 2146 : 7553 : PageClearAllVisible(BufferGetPage(buffer));
5243 rhaas@postgresql.org 2147 : 7553 : visibilitymap_clear(relation,
2148 : 7553 : ItemPointerGetBlockNumber(&(heaptup->t_self)),
2149 : : vmbuffer, VISIBILITYMAP_VALID_BITS);
2150 : : }
2151 : :
2152 : : /*
2153 : : * XXX Should we set PageSetPrunable on this page ?
2154 : : *
2155 : : * The inserting transaction may eventually abort thus making this tuple
2156 : : * DEAD and hence available for pruning. Though we don't want to optimize
2157 : : * for aborts, if no other tuple in this page is UPDATEd/DELETEd, the
2158 : : * aborted tuple will never be pruned until next vacuum is triggered.
2159 : : *
2160 : : * If you do add PageSetPrunable here, add it in heap_xlog_insert too.
2161 : : */
2162 : :
7151 tgl@sss.pgh.pa.us 2163 : 8416401 : MarkBufferDirty(buffer);
2164 : :
2165 : : /* XLOG stuff */
2033 noah@leadboat.com 2166 [ + + + + : 8416401 : if (RelationNeedsWAL(relation))
+ + + + ]
2167 : : {
2168 : : xl_heap_insert xlrec;
2169 : : xl_heap_header xlhdr;
2170 : : XLogRecPtr recptr;
3478 kgrittn@postgresql.o 2171 : 7065384 : Page page = BufferGetPage(buffer);
8986 bruce@momjian.us 2172 : 7065384 : uint8 info = XLOG_HEAP_INSERT;
3995 heikki.linnakangas@i 2173 : 7065384 : int bufflags = 0;
2174 : :
2175 : : /*
2176 : : * If this is a catalog, we need to transmit combo CIDs to properly
2177 : : * decode, so log that as well.
2178 : : */
4340 rhaas@postgresql.org 2179 [ + + + - : 7065384 : if (RelationIsAccessibleInLogicalDecoding(relation))
- + - - -
- + + + +
- + - - +
+ ]
2180 : 3288 : log_heap_new_cid(relation, heaptup);
2181 : :
2182 : : /*
2183 : : * If this is the single and first tuple on page, we can reinit the
2184 : : * page instead of restoring the whole thing. Set flag, and hide
2185 : : * buffer references from XLogInsert.
2186 : : */
3995 heikki.linnakangas@i 2187 [ + + + + ]: 7154697 : if (ItemPointerGetOffsetNumber(&(heaptup->t_self)) == FirstOffsetNumber &&
2188 : 89313 : PageGetMaxOffsetNumber(page) == FirstOffsetNumber)
2189 : : {
2190 : 88210 : info |= XLOG_HEAP_INIT_PAGE;
2191 : 88210 : bufflags |= REGBUF_WILL_INIT;
2192 : : }
2193 : :
2194 : 7065384 : xlrec.offnum = ItemPointerGetOffsetNumber(&heaptup->t_self);
3826 andres@anarazel.de 2195 : 7065384 : xlrec.flags = 0;
2196 [ + + ]: 7065384 : if (all_visible_cleared)
2197 : 7550 : xlrec.flags |= XLH_INSERT_ALL_VISIBLE_CLEARED;
2198 [ + + ]: 7065384 : if (options & HEAP_INSERT_SPECULATIVE)
2199 : 2070 : xlrec.flags |= XLH_INSERT_IS_SPECULATIVE;
3995 heikki.linnakangas@i 2200 [ - + ]: 7065384 : Assert(ItemPointerGetBlockNumber(&heaptup->t_self) == BufferGetBlockNumber(buffer));
2201 : :
2202 : : /*
2203 : : * For logical decoding, we need the tuple even if we're doing a full
2204 : : * page write, so make sure it's included even if we take a full-page
2205 : : * image. (XXX We could alternatively store a pointer into the FPW).
2206 : : */
2575 andres@anarazel.de 2207 [ + + + - : 7065384 : if (RelationIsLogicallyLogged(relation) &&
- + - - -
- + - +
+ ]
2208 [ + + ]: 249923 : !(options & HEAP_INSERT_NO_LOGICAL))
2209 : : {
3826 2210 : 249896 : xlrec.flags |= XLH_INSERT_CONTAINS_NEW_TUPLE;
3995 heikki.linnakangas@i 2211 : 249896 : bufflags |= REGBUF_KEEP_DATA;
2212 : :
1907 akapila@postgresql.o 2213 [ + + ]: 249896 : if (IsToastRelation(relation))
2214 : 1786 : xlrec.flags |= XLH_INSERT_ON_TOAST_RELATION;
2215 : : }
2216 : :
3995 heikki.linnakangas@i 2217 : 7065384 : XLogBeginInsert();
259 peter@eisentraut.org 2218 : 7065384 : XLogRegisterData(&xlrec, SizeOfHeapInsert);
2219 : :
3995 heikki.linnakangas@i 2220 : 7065384 : xlhdr.t_infomask2 = heaptup->t_data->t_infomask2;
2221 : 7065384 : xlhdr.t_infomask = heaptup->t_data->t_infomask;
2222 : 7065384 : xlhdr.t_hoff = heaptup->t_data->t_hoff;
2223 : :
2224 : : /*
2225 : : * note we mark xlhdr as belonging to buffer; if XLogInsert decides to
2226 : : * write the whole page to the xlog, we don't need to store
2227 : : * xl_heap_header in the xlog.
2228 : : */
2229 : 7065384 : XLogRegisterBuffer(0, buffer, REGBUF_STANDARD | bufflags);
259 peter@eisentraut.org 2230 : 7065384 : XLogRegisterBufData(0, &xlhdr, SizeOfHeapHeader);
2231 : : /* PG73FORMAT: write bitmap [+ padding] [+ oid] + data */
3995 heikki.linnakangas@i 2232 : 7065384 : XLogRegisterBufData(0,
3902 tgl@sss.pgh.pa.us 2233 : 7065384 : (char *) heaptup->t_data + SizeofHeapTupleHeader,
2234 : 7065384 : heaptup->t_len - SizeofHeapTupleHeader);
2235 : :
2236 : : /* filtering by origin on a row level is much more efficient */
3232 andres@anarazel.de 2237 : 7065384 : XLogSetRecordFlags(XLOG_INCLUDE_ORIGIN);
2238 : :
3995 heikki.linnakangas@i 2239 : 7065384 : recptr = XLogInsert(RM_HEAP_ID, info);
2240 : :
9070 vadim4o@yahoo.com 2241 : 7065384 : PageSetLSN(page, recptr);
2242 : : }
2243 : :
9055 tgl@sss.pgh.pa.us 2244 [ - + ]: 8416401 : END_CRIT_SECTION();
2245 : :
7151 2246 : 8416401 : UnlockReleaseBuffer(buffer);
5243 rhaas@postgresql.org 2247 [ + + ]: 8416401 : if (vmbuffer != InvalidBuffer)
2248 : 7836 : ReleaseBuffer(vmbuffer);
2249 : :
2250 : : /*
2251 : : * If tuple is cachable, mark it for invalidation from the caches in case
2252 : : * we abort. Note it is OK to do this after releasing the buffer, because
2253 : : * the heaptup data structure is all in local memory, not in the shared
2254 : : * buffer.
2255 : : */
5187 tgl@sss.pgh.pa.us 2256 : 8416401 : CacheInvalidateHeapTuple(relation, heaptup, NULL);
2257 : :
2258 : : /* Note: speculative insertions are counted too, even if aborted later */
5102 heikki.linnakangas@i 2259 : 8416401 : pgstat_count_heap_insert(relation, 1);
2260 : :
2261 : : /*
2262 : : * If heaptup is a private copy, release it. Don't forget to copy t_self
2263 : : * back to the caller's image, too.
2264 : : */
7282 tgl@sss.pgh.pa.us 2265 [ + + ]: 8416401 : if (heaptup != tup)
2266 : : {
2267 : 18347 : tup->t_self = heaptup->t_self;
2268 : 18347 : heap_freetuple(heaptup);
2269 : : }
10703 scrappy@hub.org 2270 : 8416401 : }
2271 : :
2272 : : /*
2273 : : * Subroutine for heap_insert(). Prepares a tuple for insertion. This sets the
2274 : : * tuple header fields and toasts the tuple if necessary. Returns a toasted
2275 : : * version of the tuple if it was toasted, or the original tuple if not. Note
2276 : : * that in any case, the header fields are also set in the original tuple.
2277 : : */
2278 : : static HeapTuple
5102 heikki.linnakangas@i 2279 : 9982214 : heap_prepare_insert(Relation relation, HeapTuple tup, TransactionId xid,
2280 : : CommandId cid, int options)
2281 : : {
2282 : : /*
2283 : : * To allow parallel inserts, we need to ensure that they are safe to be
2284 : : * performed in workers. We have the infrastructure to allow parallel
2285 : : * inserts in general except for the cases where inserts generate a new
2286 : : * CommandId (eg. inserts into a table having a foreign key column).
2287 : : */
2945 rhaas@postgresql.org 2288 [ - + ]: 9982214 : if (IsParallelWorker())
3834 rhaas@postgresql.org 2289 [ # # ]:UBC 0 : ereport(ERROR,
2290 : : (errcode(ERRCODE_INVALID_TRANSACTION_STATE),
2291 : : errmsg("cannot insert tuples in a parallel worker")));
2292 : :
5102 heikki.linnakangas@i 2293 :CBC 9982214 : tup->t_data->t_infomask &= ~(HEAP_XACT_MASK);
2294 : 9982214 : tup->t_data->t_infomask2 &= ~(HEAP2_XACT_MASK);
2295 : 9982214 : tup->t_data->t_infomask |= HEAP_XMAX_INVALID;
4328 rhaas@postgresql.org 2296 : 9982214 : HeapTupleHeaderSetXmin(tup->t_data, xid);
4713 simon@2ndQuadrant.co 2297 [ + + ]: 9982214 : if (options & HEAP_INSERT_FROZEN)
4328 rhaas@postgresql.org 2298 : 102088 : HeapTupleHeaderSetXminFrozen(tup->t_data);
2299 : :
5102 heikki.linnakangas@i 2300 : 9982214 : HeapTupleHeaderSetCmin(tup->t_data, cid);
3051 tgl@sss.pgh.pa.us 2301 : 9982214 : HeapTupleHeaderSetXmax(tup->t_data, 0); /* for cleanliness */
5102 heikki.linnakangas@i 2302 : 9982214 : tup->t_tableOid = RelationGetRelid(relation);
2303 : :
2304 : : /*
2305 : : * If the new tuple is too big for storage or contains already toasted
2306 : : * out-of-line attributes from some other relation, invoke the toaster.
2307 : : */
4622 kgrittn@postgresql.o 2308 [ + + ]: 9982214 : if (relation->rd_rel->relkind != RELKIND_RELATION &&
2309 [ + + ]: 31111 : relation->rd_rel->relkind != RELKIND_MATVIEW)
2310 : : {
2311 : : /* toast table entries should never be recursively toasted */
5102 heikki.linnakangas@i 2312 [ - + ]: 31063 : Assert(!HeapTupleHasExternal(tup));
2313 : 31063 : return tup;
2314 : : }
2315 [ + + + + ]: 9951151 : else if (HeapTupleHasExternal(tup) || tup->t_len > TOAST_TUPLE_THRESHOLD)
2216 rhaas@postgresql.org 2316 : 18391 : return heap_toast_insert_or_update(relation, tup, NULL, options);
2317 : : else
5102 heikki.linnakangas@i 2318 : 9932760 : return tup;
2319 : : }
2320 : :
2321 : : /*
2322 : : * Helper for heap_multi_insert() that computes the number of entire pages
2323 : : * that inserting the remaining heaptuples requires. Used to determine how
2324 : : * much the relation needs to be extended by.
2325 : : */
2326 : : static int
936 andres@anarazel.de 2327 : 358375 : heap_multi_insert_pages(HeapTuple *heaptuples, int done, int ntuples, Size saveFreeSpace)
2328 : : {
2329 : 358375 : size_t page_avail = BLCKSZ - SizeOfPageHeaderData - saveFreeSpace;
2330 : 358375 : int npages = 1;
2331 : :
2332 [ + + ]: 2606591 : for (int i = done; i < ntuples; i++)
2333 : : {
2334 : 2248216 : size_t tup_sz = sizeof(ItemIdData) + MAXALIGN(heaptuples[i]->t_len);
2335 : :
2336 [ + + ]: 2248216 : if (page_avail < tup_sz)
2337 : : {
2338 : 16326 : npages++;
2339 : 16326 : page_avail = BLCKSZ - SizeOfPageHeaderData - saveFreeSpace;
2340 : : }
2341 : 2248216 : page_avail -= tup_sz;
2342 : : }
2343 : :
2344 : 358375 : return npages;
2345 : : }
2346 : :
2347 : : /*
2348 : : * heap_multi_insert - insert multiple tuples into a heap
2349 : : *
2350 : : * This is like heap_insert(), but inserts multiple tuples in one operation.
2351 : : * That's faster than calling heap_insert() in a loop, because when multiple
2352 : : * tuples can be inserted on a single page, we can write just a single WAL
2353 : : * record covering all of them, and only need to lock/unlock the page once.
2354 : : *
2355 : : * Note: this leaks memory into the current memory context. You can create a
2356 : : * temporary context before calling this, if that's a problem.
2357 : : */
2358 : : void
2399 2359 : 351747 : heap_multi_insert(Relation relation, TupleTableSlot **slots, int ntuples,
2360 : : CommandId cid, int options, BulkInsertState bistate)
2361 : : {
5102 heikki.linnakangas@i 2362 : 351747 : TransactionId xid = GetCurrentTransactionId();
2363 : : HeapTuple *heaptuples;
2364 : : int i;
2365 : : int ndone;
2366 : : PGAlignedBlock scratch;
2367 : : Page page;
1745 tomas.vondra@postgre 2368 : 351747 : Buffer vmbuffer = InvalidBuffer;
2369 : : bool needwal;
2370 : : Size saveFreeSpace;
4340 rhaas@postgresql.org 2371 [ + + + - : 351747 : bool need_tuple_data = RelationIsLogicallyLogged(relation);
- + - - -
- + - +
+ ]
2372 [ + + + - : 351747 : bool need_cids = RelationIsAccessibleInLogicalDecoding(relation);
- + - - -
- + + - +
- - - - -
- ]
936 andres@anarazel.de 2373 : 351747 : bool starting_with_empty_page = false;
2374 : 351747 : int npages = 0;
2375 : 351747 : int npages_used = 0;
2376 : :
2377 : : /* currently not needed (thus unsupported) for heap_multi_insert() */
1096 peter@eisentraut.org 2378 [ - + ]: 351747 : Assert(!(options & HEAP_INSERT_NO_LOGICAL));
2379 : :
151 nathan@postgresql.or 2380 : 351747 : AssertHasSnapshotForToast(relation);
2381 : :
2033 noah@leadboat.com 2382 [ + + + + : 351747 : needwal = RelationNeedsWAL(relation);
+ + + + ]
565 akorotkov@postgresql 2383 [ + + ]: 351747 : saveFreeSpace = RelationGetTargetPageFreeSpace(relation,
2384 : : HEAP_DEFAULT_FILLFACTOR);
2385 : :
2386 : : /* Toast and set header data in all the slots */
5102 heikki.linnakangas@i 2387 : 351747 : heaptuples = palloc(ntuples * sizeof(HeapTuple));
2388 [ + + ]: 1917548 : for (i = 0; i < ntuples; i++)
2389 : : {
2390 : : HeapTuple tuple;
2391 : :
2399 andres@anarazel.de 2392 : 1565801 : tuple = ExecFetchSlotHeapTuple(slots[i], true, NULL);
2393 : 1565801 : slots[i]->tts_tableOid = RelationGetRelid(relation);
2394 : 1565801 : tuple->t_tableOid = slots[i]->tts_tableOid;
2395 : 1565801 : heaptuples[i] = heap_prepare_insert(relation, tuple, xid, cid,
2396 : : options);
2397 : : }
2398 : :
2399 : : /*
2400 : : * We're about to do the actual inserts -- but check for conflict first,
2401 : : * to minimize the possibility of having to roll back work we've just
2402 : : * done.
2403 : : *
2404 : : * A check here does not definitively prevent a serialization anomaly;
2405 : : * that check MUST be done at least past the point of acquiring an
2406 : : * exclusive buffer content lock on every buffer that will be affected,
2407 : : * and MAY be done after all inserts are reflected in the buffers and
2408 : : * those locks are released; otherwise there is a race condition. Since
2409 : : * multiple buffers can be locked and unlocked in the loop below, and it
2410 : : * would not be feasible to identify and lock all of those buffers before
2411 : : * the loop, we must do a final check at the end.
2412 : : *
2413 : : * The check here could be omitted with no loss of correctness; it is
2414 : : * present strictly as an optimization.
2415 : : *
2416 : : * For heap inserts, we only need to check for table-level SSI locks. Our
2417 : : * new tuples can't possibly conflict with existing tuple locks, and heap
2418 : : * page locks are only consolidated versions of tuple locks; they do not
2419 : : * lock "gaps" as index page locks do. So we don't need to specify a
2420 : : * buffer when making the call, which makes for a faster check.
2421 : : */
2100 tmunro@postgresql.or 2422 : 351747 : CheckForSerializableConflictIn(relation, NULL, InvalidBlockNumber);
2423 : :
5102 heikki.linnakangas@i 2424 : 351747 : ndone = 0;
2425 [ + + ]: 718613 : while (ndone < ntuples)
2426 : : {
2427 : : Buffer buffer;
2428 : 366866 : bool all_visible_cleared = false;
1745 tomas.vondra@postgre 2429 : 366866 : bool all_frozen_set = false;
2430 : : int nthispage;
2431 : :
4145 rhaas@postgresql.org 2432 [ - + ]: 366866 : CHECK_FOR_INTERRUPTS();
2433 : :
2434 : : /*
2435 : : * Compute number of pages needed to fit the to-be-inserted tuples in
2436 : : * the worst case. This will be used to determine how much to extend
2437 : : * the relation by in RelationGetBufferForTuple(), if needed. If we
2438 : : * filled a prior page from scratch, we can just update our last
2439 : : * computation, but if we started with a partially filled page,
2440 : : * recompute from scratch, the number of potentially required pages
2441 : : * can vary due to tuples needing to fit onto the page, page headers
2442 : : * etc.
2443 : : */
936 andres@anarazel.de 2444 [ + + + + ]: 366866 : if (ndone == 0 || !starting_with_empty_page)
2445 : : {
2446 : 358375 : npages = heap_multi_insert_pages(heaptuples, ndone, ntuples,
2447 : : saveFreeSpace);
2448 : 358375 : npages_used = 0;
2449 : : }
2450 : : else
2451 : 8491 : npages_used++;
2452 : :
2453 : : /*
2454 : : * Find buffer where at least the next tuple will fit. If the page is
2455 : : * all-visible, this will also pin the requisite visibility map page.
2456 : : *
2457 : : * Also pin visibility map page if COPY FREEZE inserts tuples into an
2458 : : * empty page. See all_frozen_set below.
2459 : : */
5102 heikki.linnakangas@i 2460 : 366866 : buffer = RelationGetBufferForTuple(relation, heaptuples[ndone]->t_len,
2461 : : InvalidBuffer, options, bistate,
2462 : : &vmbuffer, NULL,
2463 : : npages - npages_used);
3478 kgrittn@postgresql.o 2464 : 366866 : page = BufferGetPage(buffer);
2465 : :
1745 tomas.vondra@postgre 2466 : 366866 : starting_with_empty_page = PageGetMaxOffsetNumber(page) == 0;
2467 : :
2468 [ + + + + ]: 366866 : if (starting_with_empty_page && (options & HEAP_INSERT_FROZEN))
2469 : : {
2470 : 1661 : all_frozen_set = true;
2471 : : /* Lock the vmbuffer before entering the critical section */
19 melanieplageman@gmai 2472 :GNC 1661 : LockBuffer(vmbuffer, BUFFER_LOCK_EXCLUSIVE);
2473 : : }
2474 : :
2475 : : /* NO EREPORT(ERROR) from here till changes are logged */
5102 heikki.linnakangas@i 2476 :CBC 366866 : START_CRIT_SECTION();
2477 : :
2478 : : /*
2479 : : * RelationGetBufferForTuple has ensured that the first tuple fits.
2480 : : * Put that on the page, and then as many other tuples as fit.
2481 : : */
3826 andres@anarazel.de 2482 : 366866 : RelationPutHeapTuple(relation, buffer, heaptuples[ndone], false);
2483 : :
2484 : : /*
2485 : : * For logical decoding we need combo CIDs to properly decode the
2486 : : * catalog.
2487 : : */
2072 michael@paquier.xyz 2488 [ + + + + ]: 366866 : if (needwal && need_cids)
2489 : 4825 : log_heap_new_cid(relation, heaptuples[ndone]);
2490 : :
4703 heikki.linnakangas@i 2491 [ + + ]: 1565801 : for (nthispage = 1; ndone + nthispage < ntuples; nthispage++)
2492 : : {
5102 2493 : 1214054 : HeapTuple heaptup = heaptuples[ndone + nthispage];
2494 : :
4913 2495 [ + + ]: 1214054 : if (PageGetHeapFreeSpace(page) < MAXALIGN(heaptup->t_len) + saveFreeSpace)
5102 2496 : 15119 : break;
2497 : :
3826 andres@anarazel.de 2498 : 1198935 : RelationPutHeapTuple(relation, buffer, heaptup, false);
2499 : :
2500 : : /*
2501 : : * For logical decoding we need combo CIDs to properly decode the
2502 : : * catalog.
2503 : : */
3995 heikki.linnakangas@i 2504 [ + + + + ]: 1198935 : if (needwal && need_cids)
2505 : 4549 : log_heap_new_cid(relation, heaptup);
2506 : : }
2507 : :
2508 : : /*
2509 : : * If the page is all visible, need to clear that, unless we're only
2510 : : * going to add further frozen rows to it.
2511 : : *
2512 : : * If we're only adding already frozen rows to a previously empty
2513 : : * page, mark it as all-frozen and update the visibility map. We're
2514 : : * already holding a pin on the vmbuffer.
2515 : : */
1745 tomas.vondra@postgre 2516 [ + + + + ]: 366866 : if (PageIsAllVisible(page) && !(options & HEAP_INSERT_FROZEN))
2517 : : {
4891 rhaas@postgresql.org 2518 : 3631 : all_visible_cleared = true;
2519 : 3631 : PageClearAllVisible(page);
2520 : 3631 : visibilitymap_clear(relation,
2521 : : BufferGetBlockNumber(buffer),
2522 : : vmbuffer, VISIBILITYMAP_VALID_BITS);
2523 : : }
1745 tomas.vondra@postgre 2524 [ + + ]: 363235 : else if (all_frozen_set)
2525 : : {
2526 : 1661 : PageSetAllVisible(page);
19 melanieplageman@gmai 2527 :GNC 1661 : visibilitymap_set_vmbits(BufferGetBlockNumber(buffer),
2528 : : vmbuffer,
2529 : : VISIBILITYMAP_ALL_VISIBLE |
2530 : : VISIBILITYMAP_ALL_FROZEN,
2531 : : relation->rd_locator);
2532 : : }
2533 : :
2534 : : /*
2535 : : * XXX Should we set PageSetPrunable on this page ? See heap_insert()
2536 : : */
2537 : :
5102 heikki.linnakangas@i 2538 :CBC 366866 : MarkBufferDirty(buffer);
2539 : :
2540 : : /* XLOG stuff */
2541 [ + + ]: 366866 : if (needwal)
2542 : : {
2543 : : XLogRecPtr recptr;
2544 : : xl_heap_multi_insert *xlrec;
2545 : 362496 : uint8 info = XLOG_HEAP2_MULTI_INSERT;
2546 : : char *tupledata;
2547 : : int totaldatalen;
2614 tgl@sss.pgh.pa.us 2548 : 362496 : char *scratchptr = scratch.data;
2549 : : bool init;
3995 heikki.linnakangas@i 2550 : 362496 : int bufflags = 0;
2551 : :
2552 : : /*
2553 : : * If the page was previously empty, we can reinit the page
2554 : : * instead of restoring the whole thing.
2555 : : */
1745 tomas.vondra@postgre 2556 : 362496 : init = starting_with_empty_page;
2557 : :
2558 : : /* allocate xl_heap_multi_insert struct from the scratch area */
5102 heikki.linnakangas@i 2559 : 362496 : xlrec = (xl_heap_multi_insert *) scratchptr;
2560 : 362496 : scratchptr += SizeOfHeapMultiInsert;
2561 : :
2562 : : /*
2563 : : * Allocate offsets array. Unless we're reinitializing the page,
2564 : : * in that case the tuples are stored in order starting at
2565 : : * FirstOffsetNumber and we don't need to store the offsets
2566 : : * explicitly.
2567 : : */
2568 [ + + ]: 362496 : if (!init)
2569 : 350140 : scratchptr += nthispage * sizeof(OffsetNumber);
2570 : :
2571 : : /* the rest of the scratch space is used for tuple data */
2572 : 362496 : tupledata = scratchptr;
2573 : :
2574 : : /* check that the mutually exclusive flags are not both set */
1630 tgl@sss.pgh.pa.us 2575 [ + + - + ]: 362496 : Assert(!(all_visible_cleared && all_frozen_set));
2576 : :
1745 tomas.vondra@postgre 2577 : 362496 : xlrec->flags = 0;
2578 [ + + ]: 362496 : if (all_visible_cleared)
2579 : 3631 : xlrec->flags = XLH_INSERT_ALL_VISIBLE_CLEARED;
2580 : :
2581 : : /*
2582 : : * We don't have to worry about including a conflict xid in the
2583 : : * WAL record, as HEAP_INSERT_FROZEN intentionally violates
2584 : : * visibility rules.
2585 : : */
2586 [ + + ]: 362496 : if (all_frozen_set)
2587 : 13 : xlrec->flags = XLH_INSERT_ALL_FROZEN_SET;
2588 : :
5102 heikki.linnakangas@i 2589 : 362496 : xlrec->ntuples = nthispage;
2590 : :
2591 : : /*
2592 : : * Write out an xl_multi_insert_tuple and the tuple data itself
2593 : : * for each tuple.
2594 : : */
2595 [ + + ]: 1622882 : for (i = 0; i < nthispage; i++)
2596 : : {
2597 : 1260386 : HeapTuple heaptup = heaptuples[ndone + i];
2598 : : xl_multi_insert_tuple *tuphdr;
2599 : : int datalen;
2600 : :
2601 [ + + ]: 1260386 : if (!init)
2602 : 738920 : xlrec->offsets[i] = ItemPointerGetOffsetNumber(&heaptup->t_self);
2603 : : /* xl_multi_insert_tuple needs two-byte alignment. */
2604 : 1260386 : tuphdr = (xl_multi_insert_tuple *) SHORTALIGN(scratchptr);
2605 : 1260386 : scratchptr = ((char *) tuphdr) + SizeOfMultiInsertTuple;
2606 : :
2607 : 1260386 : tuphdr->t_infomask2 = heaptup->t_data->t_infomask2;
2608 : 1260386 : tuphdr->t_infomask = heaptup->t_data->t_infomask;
2609 : 1260386 : tuphdr->t_hoff = heaptup->t_data->t_hoff;
2610 : :
2611 : : /* write bitmap [+ padding] [+ oid] + data */
3902 tgl@sss.pgh.pa.us 2612 : 1260386 : datalen = heaptup->t_len - SizeofHeapTupleHeader;
5102 heikki.linnakangas@i 2613 : 1260386 : memcpy(scratchptr,
3902 tgl@sss.pgh.pa.us 2614 : 1260386 : (char *) heaptup->t_data + SizeofHeapTupleHeader,
2615 : : datalen);
5102 heikki.linnakangas@i 2616 : 1260386 : tuphdr->datalen = datalen;
2617 : 1260386 : scratchptr += datalen;
2618 : : }
2619 : 362496 : totaldatalen = scratchptr - tupledata;
2614 tgl@sss.pgh.pa.us 2620 [ - + ]: 362496 : Assert((scratchptr - scratch.data) < BLCKSZ);
2621 : :
4340 rhaas@postgresql.org 2622 [ + + ]: 362496 : if (need_tuple_data)
3826 andres@anarazel.de 2623 : 72 : xlrec->flags |= XLH_INSERT_CONTAINS_NEW_TUPLE;
2624 : :
2625 : : /*
2626 : : * Signal that this is the last xl_heap_multi_insert record
2627 : : * emitted by this call to heap_multi_insert(). Needed for logical
2628 : : * decoding so it knows when to cleanup temporary data.
2629 : : */
3995 heikki.linnakangas@i 2630 [ + + ]: 362496 : if (ndone + nthispage == ntuples)
3826 andres@anarazel.de 2631 : 351228 : xlrec->flags |= XLH_INSERT_LAST_IN_MULTI;
2632 : :
5102 heikki.linnakangas@i 2633 [ + + ]: 362496 : if (init)
2634 : : {
2635 : 12356 : info |= XLOG_HEAP_INIT_PAGE;
3995 2636 : 12356 : bufflags |= REGBUF_WILL_INIT;
2637 : : }
2638 : :
2639 : : /*
2640 : : * If we're doing logical decoding, include the new tuple data
2641 : : * even if we take a full-page image of the page.
2642 : : */
2643 [ + + ]: 362496 : if (need_tuple_data)
2644 : 72 : bufflags |= REGBUF_KEEP_DATA;
2645 : :
2646 : 362496 : XLogBeginInsert();
259 peter@eisentraut.org 2647 : 362496 : XLogRegisterData(xlrec, tupledata - scratch.data);
3995 heikki.linnakangas@i 2648 : 362496 : XLogRegisterBuffer(0, buffer, REGBUF_STANDARD | bufflags);
19 melanieplageman@gmai 2649 [ + + ]:GNC 362496 : if (all_frozen_set)
2650 : 13 : XLogRegisterBuffer(1, vmbuffer, 0);
2651 : :
3995 heikki.linnakangas@i 2652 :CBC 362496 : XLogRegisterBufData(0, tupledata, totaldatalen);
2653 : :
2654 : : /* filtering by origin on a row level is much more efficient */
3232 andres@anarazel.de 2655 : 362496 : XLogSetRecordFlags(XLOG_INCLUDE_ORIGIN);
2656 : :
3995 heikki.linnakangas@i 2657 : 362496 : recptr = XLogInsert(RM_HEAP2_ID, info);
2658 : :
5102 2659 : 362496 : PageSetLSN(page, recptr);
19 melanieplageman@gmai 2660 [ + + ]:GNC 362496 : if (all_frozen_set)
2661 : : {
2662 [ - + ]: 13 : Assert(BufferIsDirty(vmbuffer));
2663 : 13 : PageSetLSN(BufferGetPage(vmbuffer), recptr);
2664 : : }
2665 : : }
2666 : :
5102 heikki.linnakangas@i 2667 [ - + ]:CBC 366866 : END_CRIT_SECTION();
2668 : :
1745 tomas.vondra@postgre 2669 [ + + ]: 366866 : if (all_frozen_set)
19 melanieplageman@gmai 2670 :GNC 1661 : LockBuffer(vmbuffer, BUFFER_LOCK_UNLOCK);
2671 : :
1745 tomas.vondra@postgre 2672 :CBC 366866 : UnlockReleaseBuffer(buffer);
5102 heikki.linnakangas@i 2673 : 366866 : ndone += nthispage;
2674 : :
2675 : : /*
2676 : : * NB: Only release vmbuffer after inserting all tuples - it's fairly
2677 : : * likely that we'll insert into subsequent heap pages that are likely
2678 : : * to use the same vm page.
2679 : : */
2680 : : }
2681 : :
2682 : : /* We're done with inserting all tuples, so release the last vmbuffer. */
1745 tomas.vondra@postgre 2683 [ + + ]: 351747 : if (vmbuffer != InvalidBuffer)
2684 : 3715 : ReleaseBuffer(vmbuffer);
2685 : :
2686 : : /*
2687 : : * We're done with the actual inserts. Check for conflicts again, to
2688 : : * ensure that all rw-conflicts in to these inserts are detected. Without
2689 : : * this final check, a sequential scan of the heap may have locked the
2690 : : * table after the "before" check, missing one opportunity to detect the
2691 : : * conflict, and then scanned the table before the new tuples were there,
2692 : : * missing the other chance to detect the conflict.
2693 : : *
2694 : : * For heap inserts, we only need to check for table-level SSI locks. Our
2695 : : * new tuples can't possibly conflict with existing tuple locks, and heap
2696 : : * page locks are only consolidated versions of tuple locks; they do not
2697 : : * lock "gaps" as index page locks do. So we don't need to specify a
2698 : : * buffer when making the call.
2699 : : */
2100 tmunro@postgresql.or 2700 : 351747 : CheckForSerializableConflictIn(relation, NULL, InvalidBlockNumber);
2701 : :
2702 : : /*
2703 : : * If tuples are cachable, mark them for invalidation from the caches in
2704 : : * case we abort. Note it is OK to do this after releasing the buffer,
2705 : : * because the heaptuples data structure is all in local memory, not in
2706 : : * the shared buffer.
2707 : : */
4352 rhaas@postgresql.org 2708 [ + + ]: 351747 : if (IsCatalogRelation(relation))
2709 : : {
5102 heikki.linnakangas@i 2710 [ + + ]: 1214677 : for (i = 0; i < ntuples; i++)
2711 : 864243 : CacheInvalidateHeapTuple(relation, heaptuples[i], NULL);
2712 : : }
2713 : :
2714 : : /* copy t_self fields back to the caller's slots */
5006 2715 [ + + ]: 1917548 : for (i = 0; i < ntuples; i++)
2399 andres@anarazel.de 2716 : 1565801 : slots[i]->tts_tid = heaptuples[i]->t_self;
2717 : :
5102 heikki.linnakangas@i 2718 : 351747 : pgstat_count_heap_insert(relation, ntuples);
2719 : 351747 : }
2720 : :
2721 : : /*
2722 : : * simple_heap_insert - insert a tuple
2723 : : *
2724 : : * Currently, this routine differs from heap_insert only in supplying
2725 : : * a default command ID and not allowing access to the speedup options.
2726 : : *
2727 : : * This should be used rather than using heap_insert directly in most places
2728 : : * where we are modifying system catalogs.
2729 : : */
2730 : : void
8561 tgl@sss.pgh.pa.us 2731 : 929719 : simple_heap_insert(Relation relation, HeapTuple tup)
2732 : : {
2534 andres@anarazel.de 2733 : 929719 : heap_insert(relation, tup, GetCurrentCommandId(true), 0, NULL);
8561 tgl@sss.pgh.pa.us 2734 : 929719 : }
2735 : :
2736 : : /*
2737 : : * Given infomask/infomask2, compute the bits that must be saved in the
2738 : : * "infobits" field of xl_heap_delete, xl_heap_update, xl_heap_lock,
2739 : : * xl_heap_lock_updated WAL records.
2740 : : *
2741 : : * See fix_infomask_from_infobits.
2742 : : */
2743 : : static uint8
4661 alvherre@alvh.no-ip. 2744 : 1877951 : compute_infobits(uint16 infomask, uint16 infomask2)
2745 : : {
2746 : : return
2747 : 1877951 : ((infomask & HEAP_XMAX_IS_MULTI) != 0 ? XLHL_XMAX_IS_MULTI : 0) |
2748 : 1877951 : ((infomask & HEAP_XMAX_LOCK_ONLY) != 0 ? XLHL_XMAX_LOCK_ONLY : 0) |
2749 : 1877951 : ((infomask & HEAP_XMAX_EXCL_LOCK) != 0 ? XLHL_XMAX_EXCL_LOCK : 0) |
2750 : : /* note we ignore HEAP_XMAX_SHR_LOCK here */
2751 : 3755902 : ((infomask & HEAP_XMAX_KEYSHR_LOCK) != 0 ? XLHL_XMAX_KEYSHR_LOCK : 0) |
2752 : : ((infomask2 & HEAP_KEYS_UPDATED) != 0 ?
2753 : 1877951 : XLHL_KEYS_UPDATED : 0);
2754 : : }
2755 : :
2756 : : /*
2757 : : * Given two versions of the same t_infomask for a tuple, compare them and
2758 : : * return whether the relevant status for a tuple Xmax has changed. This is
2759 : : * used after a buffer lock has been released and reacquired: we want to ensure
2760 : : * that the tuple state continues to be the same it was when we previously
2761 : : * examined it.
2762 : : *
2763 : : * Note the Xmax field itself must be compared separately.
2764 : : */
2765 : : static inline bool
4205 2766 : 5369 : xmax_infomask_changed(uint16 new_infomask, uint16 old_infomask)
2767 : : {
4193 bruce@momjian.us 2768 : 5369 : const uint16 interesting =
2769 : : HEAP_XMAX_IS_MULTI | HEAP_XMAX_LOCK_ONLY | HEAP_LOCK_MASK;
2770 : :
4205 alvherre@alvh.no-ip. 2771 [ + + ]: 5369 : if ((new_infomask & interesting) != (old_infomask & interesting))
2772 : 11 : return true;
2773 : :
2774 : 5358 : return false;
2775 : : }
2776 : :
2777 : : /*
2778 : : * heap_delete - delete a tuple
2779 : : *
2780 : : * See table_tuple_delete() for an explanation of the parameters, except that
2781 : : * this routine directly takes a tuple rather than a slot.
2782 : : *
2783 : : * In the failure cases, the routine fills *tmfd with the tuple's t_ctid,
2784 : : * t_xmax (resolving a possible MultiXact, if necessary), and t_cmax (the last
2785 : : * only for TM_SelfModified, since we cannot obtain cmax from a combo CID
2786 : : * generated by another transaction).
2787 : : */
2788 : : TM_Result
8561 tgl@sss.pgh.pa.us 2789 : 1425669 : heap_delete(Relation relation, ItemPointer tid,
2790 : : CommandId cid, Snapshot crosscheck, bool wait,
2791 : : TM_FailureData *tmfd, bool changingPart)
2792 : : {
2793 : : TM_Result result;
7712 2794 : 1425669 : TransactionId xid = GetCurrentTransactionId();
2795 : : ItemId lp;
2796 : : HeapTupleData tp;
2797 : : Page page;
2798 : : BlockNumber block;
2799 : : Buffer buffer;
5243 rhaas@postgresql.org 2800 : 1425669 : Buffer vmbuffer = InvalidBuffer;
2801 : : TransactionId new_xmax;
2802 : : uint16 new_infomask,
2803 : : new_infomask2;
7486 tgl@sss.pgh.pa.us 2804 : 1425669 : bool have_tuple_lock = false;
2805 : : bool iscombo;
6173 heikki.linnakangas@i 2806 : 1425669 : bool all_visible_cleared = false;
4193 bruce@momjian.us 2807 : 1425669 : HeapTuple old_key_tuple = NULL; /* replica identity of the tuple */
4340 rhaas@postgresql.org 2808 : 1425669 : bool old_key_copied = false;
2809 : :
10278 bruce@momjian.us 2810 [ - + ]: 1425669 : Assert(ItemPointerIsValid(tid));
2811 : :
151 nathan@postgresql.or 2812 : 1425669 : AssertHasSnapshotForToast(relation);
2813 : :
2814 : : /*
2815 : : * Forbid this during a parallel operation, lest it allocate a combo CID.
2816 : : * Other workers might need that combo CID for visibility checks, and we
2817 : : * have no provision for broadcasting it to them.
2818 : : */
3834 rhaas@postgresql.org 2819 [ - + ]: 1425669 : if (IsInParallelMode())
3834 rhaas@postgresql.org 2820 [ # # ]:UBC 0 : ereport(ERROR,
2821 : : (errcode(ERRCODE_INVALID_TRANSACTION_STATE),
2822 : : errmsg("cannot delete tuples during a parallel operation")));
2823 : :
5243 rhaas@postgresql.org 2824 :CBC 1425669 : block = ItemPointerGetBlockNumber(tid);
2825 : 1425669 : buffer = ReadBuffer(relation, block);
3478 kgrittn@postgresql.o 2826 : 1425669 : page = BufferGetPage(buffer);
2827 : :
2828 : : /*
2829 : : * Before locking the buffer, pin the visibility map page if it appears to
2830 : : * be necessary. Since we haven't got the lock yet, someone else might be
2831 : : * in the middle of changing this, so we'll need to recheck after we have
2832 : : * the lock.
2833 : : */
5243 rhaas@postgresql.org 2834 [ + + ]: 1425669 : if (PageIsAllVisible(page))
2835 : 232 : visibilitymap_pin(relation, block, &vmbuffer);
2836 : :
9814 vadim4o@yahoo.com 2837 : 1425669 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
2838 : :
1132 jdavis@postgresql.or 2839 : 1425669 : lp = PageGetItemId(page, ItemPointerGetOffsetNumber(tid));
2840 [ - + ]: 1425669 : Assert(ItemIdIsNormal(lp));
2841 : :
2842 : 1425669 : tp.t_tableOid = RelationGetRelid(relation);
2843 : 1425669 : tp.t_data = (HeapTupleHeader) PageGetItem(page, lp);
2844 : 1425669 : tp.t_len = ItemIdGetLength(lp);
2845 : 1425669 : tp.t_self = *tid;
2846 : :
2847 : 1 : l1:
2848 : :
2849 : : /*
2850 : : * If we didn't pin the visibility map page and the page has become all
2851 : : * visible while we were busy locking the buffer, we'll have to unlock and
2852 : : * re-lock, to avoid holding the buffer lock across an I/O. That's a bit
2853 : : * unfortunate, but hopefully shouldn't happen often.
2854 : : */
5243 rhaas@postgresql.org 2855 [ + + - + ]: 1425670 : if (vmbuffer == InvalidBuffer && PageIsAllVisible(page))
2856 : : {
5243 rhaas@postgresql.org 2857 :UBC 0 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
2858 : 0 : visibilitymap_pin(relation, block, &vmbuffer);
2859 : 0 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
2860 : : }
2861 : :
4481 rhaas@postgresql.org 2862 :CBC 1425670 : result = HeapTupleSatisfiesUpdate(&tp, cid, buffer);
2863 : :
2411 andres@anarazel.de 2864 [ - + ]: 1425670 : if (result == TM_Invisible)
2865 : : {
7151 tgl@sss.pgh.pa.us 2866 :UBC 0 : UnlockReleaseBuffer(buffer);
3740 2867 [ # # ]: 0 : ereport(ERROR,
2868 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
2869 : : errmsg("attempted to delete invisible tuple")));
2870 : : }
565 akorotkov@postgresql 2871 [ + + + - ]:CBC 1425670 : else if (result == TM_BeingModified && wait)
2872 : : {
2873 : : TransactionId xwait;
2874 : : uint16 infomask;
2875 : :
2876 : : /* must copy state data before unlocking buffer */
4661 alvherre@alvh.no-ip. 2877 : 40557 : xwait = HeapTupleHeaderGetRawXmax(tp.t_data);
7486 tgl@sss.pgh.pa.us 2878 : 40557 : infomask = tp.t_data->t_infomask;
2879 : :
2880 : : /*
2881 : : * Sleep until concurrent transaction ends -- except when there's a
2882 : : * single locker and it's our own transaction. Note we don't care
2883 : : * which lock mode the locker has, because we need the strongest one.
2884 : : *
2885 : : * Before sleeping, we need to acquire tuple lock to establish our
2886 : : * priority for the tuple (see heap_lock_tuple). LockTuple will
2887 : : * release us when we are next-in-line for the tuple.
2888 : : *
2889 : : * If we are forced to "start over" below, we keep the tuple lock;
2890 : : * this arranges that we stay at the head of the line while rechecking
2891 : : * tuple state.
2892 : : */
7488 2893 [ + + ]: 40557 : if (infomask & HEAP_XMAX_IS_MULTI)
2894 : : {
2324 alvherre@alvh.no-ip. 2895 : 8 : bool current_is_member = false;
2896 : :
3854 2897 [ + - ]: 8 : if (DoesMultiXactIdConflict((MultiXactId) xwait, infomask,
2898 : : LockTupleExclusive, ¤t_is_member))
2899 : : {
2900 : 8 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
2901 : :
2902 : : /*
2903 : : * Acquire the lock, if necessary (but skip it when we're
2904 : : * requesting a lock and already have one; avoids deadlock).
2905 : : */
2324 2906 [ + + ]: 8 : if (!current_is_member)
2907 : 6 : heap_acquire_tuplock(relation, &(tp.t_self), LockTupleExclusive,
2908 : : LockWaitBlock, &have_tuple_lock);
2909 : :
2910 : : /* wait for multixact */
3854 2911 : 8 : MultiXactIdWait((MultiXactId) xwait, MultiXactStatusUpdate, infomask,
2912 : : relation, &(tp.t_self), XLTW_Delete,
2913 : : NULL);
2914 : 8 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
2915 : :
2916 : : /*
2917 : : * If xwait had just locked the tuple then some other xact
2918 : : * could update this tuple before we get to this point. Check
2919 : : * for xmax change, and start over if so.
2920 : : *
2921 : : * We also must start over if we didn't pin the VM page, and
2922 : : * the page has become all visible.
2923 : : */
1132 jdavis@postgresql.or 2924 [ + - + - : 16 : if ((vmbuffer == InvalidBuffer && PageIsAllVisible(page)) ||
+ - ]
2925 [ - + ]: 16 : xmax_infomask_changed(tp.t_data->t_infomask, infomask) ||
3854 alvherre@alvh.no-ip. 2926 : 8 : !TransactionIdEquals(HeapTupleHeaderGetRawXmax(tp.t_data),
2927 : : xwait))
3854 alvherre@alvh.no-ip. 2928 :UBC 0 : goto l1;
2929 : : }
2930 : :
2931 : : /*
2932 : : * You might think the multixact is necessarily done here, but not
2933 : : * so: it could have surviving members, namely our own xact or
2934 : : * other subxacts of this backend. It is legal for us to delete
2935 : : * the tuple in either case, however (the latter case is
2936 : : * essentially a situation of upgrading our former shared lock to
2937 : : * exclusive). We don't bother changing the on-disk hint bits
2938 : : * since we are about to overwrite the xmax altogether.
2939 : : */
2940 : : }
3854 alvherre@alvh.no-ip. 2941 [ + + ]:CBC 40549 : else if (!TransactionIdIsCurrentTransactionId(xwait))
2942 : : {
2943 : : /*
2944 : : * Wait for regular transaction to end; but first, acquire tuple
2945 : : * lock.
2946 : : */
2947 : 51 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
2948 : 51 : heap_acquire_tuplock(relation, &(tp.t_self), LockTupleExclusive,
2949 : : LockWaitBlock, &have_tuple_lock);
3919 heikki.linnakangas@i 2950 : 51 : XactLockTableWait(xwait, relation, &(tp.t_self), XLTW_Delete);
7488 tgl@sss.pgh.pa.us 2951 : 47 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
2952 : :
2953 : : /*
2954 : : * xwait is done, but if xwait had just locked the tuple then some
2955 : : * other xact could update this tuple before we get to this point.
2956 : : * Check for xmax change, and start over if so.
2957 : : *
2958 : : * We also must start over if we didn't pin the VM page, and the
2959 : : * page has become all visible.
2960 : : */
1132 jdavis@postgresql.or 2961 [ + - + - : 94 : if ((vmbuffer == InvalidBuffer && PageIsAllVisible(page)) ||
+ + ]
2962 [ - + ]: 93 : xmax_infomask_changed(tp.t_data->t_infomask, infomask) ||
4661 alvherre@alvh.no-ip. 2963 : 46 : !TransactionIdEquals(HeapTupleHeaderGetRawXmax(tp.t_data),
2964 : : xwait))
7488 tgl@sss.pgh.pa.us 2965 : 1 : goto l1;
2966 : :
2967 : : /* Otherwise check if it committed or aborted */
6650 2968 : 46 : UpdateXmaxHintBits(tp.t_data, buffer, xwait);
2969 : : }
2970 : :
2971 : : /*
2972 : : * We may overwrite if previous xmax aborted, or if it committed but
2973 : : * only locked the tuple without updating it.
2974 : : */
4661 alvherre@alvh.no-ip. 2975 [ + + + + ]: 81084 : if ((tp.t_data->t_infomask & HEAP_XMAX_INVALID) ||
2976 [ + + ]: 40562 : HEAP_XMAX_IS_LOCKED_ONLY(tp.t_data->t_infomask) ||
2977 : 30 : HeapTupleHeaderIsOnlyLocked(tp.t_data))
2411 andres@anarazel.de 2978 : 40526 : result = TM_Ok;
1709 alvherre@alvh.no-ip. 2979 [ + + ]: 26 : else if (!ItemPointerEquals(&tp.t_self, &tp.t_data->t_ctid))
2411 andres@anarazel.de 2980 : 22 : result = TM_Updated;
2981 : : else
2982 : 4 : result = TM_Deleted;
2983 : : }
2984 : :
2985 : : /* sanity check the result HeapTupleSatisfiesUpdate() and the logic above */
2986 [ + + ]: 1425665 : if (result != TM_Ok)
2987 : : {
2988 [ + + + + : 60 : Assert(result == TM_SelfModified ||
- + - - ]
2989 : : result == TM_Updated ||
2990 : : result == TM_Deleted ||
2991 : : result == TM_BeingModified);
7374 tgl@sss.pgh.pa.us 2992 [ - + ]: 60 : Assert(!(tp.t_data->t_infomask & HEAP_XMAX_INVALID));
2411 andres@anarazel.de 2993 [ + + - + ]: 60 : Assert(result != TM_Updated ||
2994 : : !ItemPointerEquals(&tp.t_self, &tp.t_data->t_ctid));
2995 : : }
2996 : :
700 heikki.linnakangas@i 2997 [ + + + - ]: 1425665 : if (crosscheck != InvalidSnapshot && result == TM_Ok)
2998 : : {
2999 : : /* Perform additional check for transaction-snapshot mode RI updates */
3000 [ + - ]: 1 : if (!HeapTupleSatisfiesVisibility(&tp, crosscheck, buffer))
3001 : 1 : result = TM_Updated;
3002 : : }
3003 : :
3004 [ + + ]: 1425665 : if (result != TM_Ok)
3005 : : {
2411 andres@anarazel.de 3006 : 61 : tmfd->ctid = tp.t_data->t_ctid;
3007 : 61 : tmfd->xmax = HeapTupleHeaderGetUpdateXid(tp.t_data);
3008 [ + + ]: 61 : if (result == TM_SelfModified)
3009 : 21 : tmfd->cmax = HeapTupleHeaderGetCmax(tp.t_data);
3010 : : else
3011 : 40 : tmfd->cmax = InvalidCommandId;
565 akorotkov@postgresql 3012 : 61 : UnlockReleaseBuffer(buffer);
7486 tgl@sss.pgh.pa.us 3013 [ + + ]: 61 : if (have_tuple_lock)
4661 alvherre@alvh.no-ip. 3014 : 26 : UnlockTupleTuplock(relation, &(tp.t_self), LockTupleExclusive);
5243 rhaas@postgresql.org 3015 [ - + ]: 61 : if (vmbuffer != InvalidBuffer)
5243 rhaas@postgresql.org 3016 :UBC 0 : ReleaseBuffer(vmbuffer);
9814 vadim4o@yahoo.com 3017 :CBC 61 : return result;
3018 : : }
3019 : :
3020 : : /*
3021 : : * We're about to do the actual delete -- check for conflict first, to
3022 : : * avoid possibly having to roll back work we've just done.
3023 : : *
3024 : : * This is safe without a recheck as long as there is no possibility of
3025 : : * another process scanning the page between this check and the delete
3026 : : * being visible to the scan (i.e., an exclusive buffer content lock is
3027 : : * continuously held from this point until the tuple delete is visible).
3028 : : */
2100 tmunro@postgresql.or 3029 : 1425604 : CheckForSerializableConflictIn(relation, tid, BufferGetBlockNumber(buffer));
3030 : :
3031 : : /* replace cid with a combo CID if necessary */
6836 tgl@sss.pgh.pa.us 3032 : 1425590 : HeapTupleHeaderAdjustCmax(tp.t_data, &cid, &iscombo);
3033 : :
3034 : : /*
3035 : : * Compute replica identity tuple before entering the critical section so
3036 : : * we don't PANIC upon a memory allocation failure.
3037 : : */
4340 rhaas@postgresql.org 3038 : 1425590 : old_key_tuple = ExtractReplicaIdentity(relation, &tp, true, &old_key_copied);
3039 : :
3040 : : /*
3041 : : * If this is the first possibly-multixact-able operation in the current
3042 : : * transaction, set my per-backend OldestMemberMXactId setting. We can be
3043 : : * certain that the transaction will never become a member of any older
3044 : : * MultiXactIds than that. (We have to do this even if we end up just
3045 : : * using our own TransactionId below, since some other backend could
3046 : : * incorporate our XID into a MultiXact immediately afterwards.)
3047 : : */
4225 heikki.linnakangas@i 3048 : 1425590 : MultiXactIdSetOldestMember();
3049 : :
3050 : 1425590 : compute_new_xmax_infomask(HeapTupleHeaderGetRawXmax(tp.t_data),
3051 : 1425590 : tp.t_data->t_infomask, tp.t_data->t_infomask2,
3052 : : xid, LockTupleExclusive, true,
3053 : : &new_xmax, &new_infomask, &new_infomask2);
3054 : :
9055 tgl@sss.pgh.pa.us 3055 : 1425590 : START_CRIT_SECTION();
3056 : :
3057 : : /*
3058 : : * If this transaction commits, the tuple will become DEAD sooner or
3059 : : * later. Set flag that this page is a candidate for pruning once our xid
3060 : : * falls below the OldestXmin horizon. If the transaction finally aborts,
3061 : : * the subsequent page pruning will be a no-op and the hint will be
3062 : : * cleared.
3063 : : */
6316 3064 [ - + + + : 1425590 : PageSetPrunable(page, xid);
+ + ]
3065 : :
6173 heikki.linnakangas@i 3066 [ + + ]: 1425590 : if (PageIsAllVisible(page))
3067 : : {
3068 : 232 : all_visible_cleared = true;
3069 : 232 : PageClearAllVisible(page);
5243 rhaas@postgresql.org 3070 : 232 : visibilitymap_clear(relation, BufferGetBlockNumber(buffer),
3071 : : vmbuffer, VISIBILITYMAP_VALID_BITS);
3072 : : }
3073 : :
3074 : : /* store transaction information of xact deleting the tuple */
4661 alvherre@alvh.no-ip. 3075 : 1425590 : tp.t_data->t_infomask &= ~(HEAP_XMAX_BITS | HEAP_MOVED);
3076 : 1425590 : tp.t_data->t_infomask2 &= ~HEAP_KEYS_UPDATED;
3077 : 1425590 : tp.t_data->t_infomask |= new_infomask;
3078 : 1425590 : tp.t_data->t_infomask2 |= new_infomask2;
6613 tgl@sss.pgh.pa.us 3079 : 1425590 : HeapTupleHeaderClearHotUpdated(tp.t_data);
4661 alvherre@alvh.no-ip. 3080 : 1425590 : HeapTupleHeaderSetXmax(tp.t_data, new_xmax);
6836 tgl@sss.pgh.pa.us 3081 : 1425590 : HeapTupleHeaderSetCmax(tp.t_data, cid, iscombo);
3082 : : /* Make sure there is no forward chain link in t_ctid */
8477 3083 : 1425590 : tp.t_data->t_ctid = tp.t_self;
3084 : :
3085 : : /* Signal that this is actually a move into another partition */
2761 andres@anarazel.de 3086 [ + + ]: 1425590 : if (changingPart)
3087 : 487 : HeapTupleHeaderSetMovedPartitions(tp.t_data);
3088 : :
7151 tgl@sss.pgh.pa.us 3089 : 1425590 : MarkBufferDirty(buffer);
3090 : :
3091 : : /*
3092 : : * XLOG stuff
3093 : : *
3094 : : * NB: heap_abort_speculative() uses the same xlog record and replay
3095 : : * routines.
3096 : : */
5433 rhaas@postgresql.org 3097 [ + + + + : 1425590 : if (RelationNeedsWAL(relation))
+ + + + ]
3098 : : {
3099 : : xl_heap_delete xlrec;
3100 : : xl_heap_header xlhdr;
3101 : : XLogRecPtr recptr;
3102 : :
3103 : : /*
3104 : : * For logical decode we need combo CIDs to properly decode the
3105 : : * catalog
3106 : : */
4340 3107 [ + + + - : 1362971 : if (RelationIsAccessibleInLogicalDecoding(relation))
- + - - -
- + + - +
- - - - -
- ]
3108 : 6152 : log_heap_new_cid(relation, &tp);
3109 : :
2761 andres@anarazel.de 3110 : 1362971 : xlrec.flags = 0;
3111 [ + + ]: 1362971 : if (all_visible_cleared)
3112 : 232 : xlrec.flags |= XLH_DELETE_ALL_VISIBLE_CLEARED;
3113 [ + + ]: 1362971 : if (changingPart)
3114 : 487 : xlrec.flags |= XLH_DELETE_IS_PARTITION_MOVE;
4661 alvherre@alvh.no-ip. 3115 : 2725942 : xlrec.infobits_set = compute_infobits(tp.t_data->t_infomask,
3116 : 1362971 : tp.t_data->t_infomask2);
3995 heikki.linnakangas@i 3117 : 1362971 : xlrec.offnum = ItemPointerGetOffsetNumber(&tp.t_self);
4661 alvherre@alvh.no-ip. 3118 : 1362971 : xlrec.xmax = new_xmax;
3119 : :
3995 heikki.linnakangas@i 3120 [ + + ]: 1362971 : if (old_key_tuple != NULL)
3121 : : {
3122 [ + + ]: 47016 : if (relation->rd_rel->relreplident == REPLICA_IDENTITY_FULL)
3826 andres@anarazel.de 3123 : 130 : xlrec.flags |= XLH_DELETE_CONTAINS_OLD_TUPLE;
3124 : : else
3125 : 46886 : xlrec.flags |= XLH_DELETE_CONTAINS_OLD_KEY;
3126 : : }
3127 : :
3995 heikki.linnakangas@i 3128 : 1362971 : XLogBeginInsert();
259 peter@eisentraut.org 3129 : 1362971 : XLogRegisterData(&xlrec, SizeOfHeapDelete);
3130 : :
3995 heikki.linnakangas@i 3131 : 1362971 : XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
3132 : :
3133 : : /*
3134 : : * Log replica identity of the deleted tuple if there is one
3135 : : */
4340 rhaas@postgresql.org 3136 [ + + ]: 1362971 : if (old_key_tuple != NULL)
3137 : : {
3138 : 47016 : xlhdr.t_infomask2 = old_key_tuple->t_data->t_infomask2;
3139 : 47016 : xlhdr.t_infomask = old_key_tuple->t_data->t_infomask;
3140 : 47016 : xlhdr.t_hoff = old_key_tuple->t_data->t_hoff;
3141 : :
259 peter@eisentraut.org 3142 : 47016 : XLogRegisterData(&xlhdr, SizeOfHeapHeader);
3995 heikki.linnakangas@i 3143 : 47016 : XLogRegisterData((char *) old_key_tuple->t_data
3144 : : + SizeofHeapTupleHeader,
3145 : 47016 : old_key_tuple->t_len
3146 : : - SizeofHeapTupleHeader);
3147 : : }
3148 : :
3149 : : /* filtering by origin on a row level is much more efficient */
3232 andres@anarazel.de 3150 : 1362971 : XLogSetRecordFlags(XLOG_INCLUDE_ORIGIN);
3151 : :
3995 heikki.linnakangas@i 3152 : 1362971 : recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_DELETE);
3153 : :
6316 tgl@sss.pgh.pa.us 3154 : 1362971 : PageSetLSN(page, recptr);
3155 : : }
3156 : :
9055 3157 [ - + ]: 1425590 : END_CRIT_SECTION();
3158 : :
9052 3159 : 1425590 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
3160 : :
5243 rhaas@postgresql.org 3161 [ + + ]: 1425590 : if (vmbuffer != InvalidBuffer)
3162 : 232 : ReleaseBuffer(vmbuffer);
3163 : :
3164 : : /*
3165 : : * If the tuple has toasted out-of-line attributes, we need to delete
3166 : : * those items too. We have to do this before releasing the buffer
3167 : : * because we need to look at the contents of the tuple, but it's OK to
3168 : : * release the content lock on the buffer first.
3169 : : */
4622 kgrittn@postgresql.o 3170 [ + + ]: 1425590 : if (relation->rd_rel->relkind != RELKIND_RELATION &&
3171 [ + + ]: 2575 : relation->rd_rel->relkind != RELKIND_MATVIEW)
3172 : : {
3173 : : /* toast table entries should never be recursively toasted */
6783 tgl@sss.pgh.pa.us 3174 [ - + ]: 2565 : Assert(!HeapTupleHasExternal(&tp));
3175 : : }
3176 [ + + ]: 1423025 : else if (HeapTupleHasExternal(&tp))
2216 rhaas@postgresql.org 3177 : 299 : heap_toast_delete(relation, &tp, false);
3178 : :
3179 : : /*
3180 : : * Mark tuple for invalidation from system caches at next command
3181 : : * boundary. We have to do this before releasing the buffer because we
3182 : : * need to look at the contents of the tuple.
3183 : : */
5187 tgl@sss.pgh.pa.us 3184 : 1425590 : CacheInvalidateHeapTuple(relation, &tp, NULL);
3185 : :
3186 : : /* Now we can release the buffer */
565 akorotkov@postgresql 3187 : 1425590 : ReleaseBuffer(buffer);
3188 : :
3189 : : /*
3190 : : * Release the lmgr tuple lock, if we had it.
3191 : : */
7486 tgl@sss.pgh.pa.us 3192 [ + + ]: 1425590 : if (have_tuple_lock)
4661 alvherre@alvh.no-ip. 3193 : 26 : UnlockTupleTuplock(relation, &(tp.t_self), LockTupleExclusive);
3194 : :
6729 tgl@sss.pgh.pa.us 3195 : 1425590 : pgstat_count_heap_delete(relation);
3196 : :
4340 rhaas@postgresql.org 3197 [ + + + + ]: 1425590 : if (old_key_tuple != NULL && old_key_copied)
3198 : 46887 : heap_freetuple(old_key_tuple);
3199 : :
2411 andres@anarazel.de 3200 : 1425590 : return TM_Ok;
3201 : : }
3202 : :
3203 : : /*
3204 : : * simple_heap_delete - delete a tuple
3205 : : *
3206 : : * This routine may be used to delete a tuple when concurrent updates of
3207 : : * the target tuple are not expected (for example, because we have a lock
3208 : : * on the relation associated with the tuple). Any failure is reported
3209 : : * via ereport().
3210 : : */
3211 : : void
9044 tgl@sss.pgh.pa.us 3212 : 616204 : simple_heap_delete(Relation relation, ItemPointer tid)
3213 : : {
3214 : : TM_Result result;
3215 : : TM_FailureData tmfd;
3216 : :
8079 3217 : 616204 : result = heap_delete(relation, tid,
3218 : : GetCurrentCommandId(true), InvalidSnapshot,
3219 : : true /* wait for commit */ ,
3220 : : &tmfd, false /* changingPart */ );
9044 3221 [ - + - - : 616204 : switch (result)
- ]
3222 : : {
2411 andres@anarazel.de 3223 :UBC 0 : case TM_SelfModified:
3224 : : /* Tuple was already updated in current command? */
8135 tgl@sss.pgh.pa.us 3225 [ # # ]: 0 : elog(ERROR, "tuple already updated by self");
3226 : : break;
3227 : :
2411 andres@anarazel.de 3228 :CBC 616204 : case TM_Ok:
3229 : : /* done successfully */
9044 tgl@sss.pgh.pa.us 3230 : 616204 : break;
3231 : :
2411 andres@anarazel.de 3232 :UBC 0 : case TM_Updated:
8135 tgl@sss.pgh.pa.us 3233 [ # # ]: 0 : elog(ERROR, "tuple concurrently updated");
3234 : : break;
3235 : :
2411 andres@anarazel.de 3236 : 0 : case TM_Deleted:
3237 [ # # ]: 0 : elog(ERROR, "tuple concurrently deleted");
3238 : : break;
3239 : :
9044 tgl@sss.pgh.pa.us 3240 : 0 : default:
8135 3241 [ # # ]: 0 : elog(ERROR, "unrecognized heap_delete status: %u", result);
3242 : : break;
3243 : : }
9044 tgl@sss.pgh.pa.us 3244 :CBC 616204 : }
3245 : :
3246 : : /*
3247 : : * heap_update - replace a tuple
3248 : : *
3249 : : * See table_tuple_update() for an explanation of the parameters, except that
3250 : : * this routine directly takes a tuple rather than a slot.
3251 : : *
3252 : : * In the failure cases, the routine fills *tmfd with the tuple's t_ctid,
3253 : : * t_xmax (resolving a possible MultiXact, if necessary), and t_cmax (the last
3254 : : * only for TM_SelfModified, since we cannot obtain cmax from a combo CID
3255 : : * generated by another transaction).
3256 : : */
3257 : : TM_Result
9470 bruce@momjian.us 3258 : 304307 : heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
3259 : : CommandId cid, Snapshot crosscheck, bool wait,
3260 : : TM_FailureData *tmfd, LockTupleMode *lockmode,
3261 : : TU_UpdateIndexes *update_indexes)
3262 : : {
3263 : : TM_Result result;
7712 tgl@sss.pgh.pa.us 3264 : 304307 : TransactionId xid = GetCurrentTransactionId();
3265 : : Bitmapset *hot_attrs;
3266 : : Bitmapset *sum_attrs;
3267 : : Bitmapset *key_attrs;
3268 : : Bitmapset *id_attrs;
3269 : : Bitmapset *interesting_attrs;
3270 : : Bitmapset *modified_attrs;
3271 : : ItemId lp;
3272 : : HeapTupleData oldtup;
3273 : : HeapTuple heaptup;
4340 rhaas@postgresql.org 3274 : 304307 : HeapTuple old_key_tuple = NULL;
3275 : 304307 : bool old_key_copied = false;
3276 : : Page page;
3277 : : BlockNumber block;
3278 : : MultiXactStatus mxact_status;
3279 : : Buffer buffer,
3280 : : newbuf,
5243 3281 : 304307 : vmbuffer = InvalidBuffer,
3282 : 304307 : vmbuffer_new = InvalidBuffer;
3283 : : bool need_toast;
3284 : : Size newtupsize,
3285 : : pagefree;
7486 tgl@sss.pgh.pa.us 3286 : 304307 : bool have_tuple_lock = false;
3287 : : bool iscombo;
6613 3288 : 304307 : bool use_hot_update = false;
953 tomas.vondra@postgre 3289 : 304307 : bool summarized_update = false;
3290 : : bool key_intact;
6173 heikki.linnakangas@i 3291 : 304307 : bool all_visible_cleared = false;
3292 : 304307 : bool all_visible_cleared_new = false;
3293 : : bool checked_lockers;
3294 : : bool locker_remains;
1352 akapila@postgresql.o 3295 : 304307 : bool id_has_external = false;
3296 : : TransactionId xmax_new_tuple,
3297 : : xmax_old_tuple;
3298 : : uint16 infomask_old_tuple,
3299 : : infomask2_old_tuple,
3300 : : infomask_new_tuple,
3301 : : infomask2_new_tuple;
3302 : :
10278 bruce@momjian.us 3303 [ - + ]: 304307 : Assert(ItemPointerIsValid(otid));
3304 : :
3305 : : /* Cheap, simplistic check that the tuple matches the rel's rowtype. */
1632 tgl@sss.pgh.pa.us 3306 [ - + ]: 304307 : Assert(HeapTupleHeaderGetNatts(newtup->t_data) <=
3307 : : RelationGetNumberOfAttributes(relation));
3308 : :
151 nathan@postgresql.or 3309 : 304307 : AssertHasSnapshotForToast(relation);
3310 : :
3311 : : /*
3312 : : * Forbid this during a parallel operation, lest it allocate a combo CID.
3313 : : * Other workers might need that combo CID for visibility checks, and we
3314 : : * have no provision for broadcasting it to them.
3315 : : */
3834 rhaas@postgresql.org 3316 [ - + ]: 304307 : if (IsInParallelMode())
3834 rhaas@postgresql.org 3317 [ # # ]:UBC 0 : ereport(ERROR,
3318 : : (errcode(ERRCODE_INVALID_TRANSACTION_STATE),
3319 : : errmsg("cannot update tuples during a parallel operation")));
3320 : :
3321 : : #ifdef USE_ASSERT_CHECKING
399 noah@leadboat.com 3322 :CBC 304307 : check_lock_if_inplace_updateable_rel(relation, otid, newtup);
3323 : : #endif
3324 : :
3325 : : /*
3326 : : * Fetch the list of attributes to be checked for various operations.
3327 : : *
3328 : : * For HOT considerations, this is wasted effort if we fail to update or
3329 : : * have to put the new tuple on a different page. But we must compute the
3330 : : * list before obtaining buffer lock --- in the worst case, if we are
3331 : : * doing an update on one of the relevant system catalogs, we could
3332 : : * deadlock if we try to fetch the list later. In any case, the relcache
3333 : : * caches the data so this is usually pretty cheap.
3334 : : *
3335 : : * We also need columns used by the replica identity and columns that are
3336 : : * considered the "key" of rows in the table.
3337 : : *
3338 : : * Note that we get copies of each bitmap, so we need not worry about
3339 : : * relcache flush happening midway through.
3340 : : */
953 tomas.vondra@postgre 3341 : 304307 : hot_attrs = RelationGetIndexAttrBitmap(relation,
3342 : : INDEX_ATTR_BITMAP_HOT_BLOCKING);
3343 : 304307 : sum_attrs = RelationGetIndexAttrBitmap(relation,
3344 : : INDEX_ATTR_BITMAP_SUMMARIZED);
4340 rhaas@postgresql.org 3345 : 304307 : key_attrs = RelationGetIndexAttrBitmap(relation, INDEX_ATTR_BITMAP_KEY);
3346 : 304307 : id_attrs = RelationGetIndexAttrBitmap(relation,
3347 : : INDEX_ATTR_BITMAP_IDENTITY_KEY);
1432 pg@bowt.ie 3348 : 304307 : interesting_attrs = NULL;
3349 : 304307 : interesting_attrs = bms_add_members(interesting_attrs, hot_attrs);
953 tomas.vondra@postgre 3350 : 304307 : interesting_attrs = bms_add_members(interesting_attrs, sum_attrs);
1432 pg@bowt.ie 3351 : 304307 : interesting_attrs = bms_add_members(interesting_attrs, key_attrs);
3352 : 304307 : interesting_attrs = bms_add_members(interesting_attrs, id_attrs);
3353 : :
5243 rhaas@postgresql.org 3354 : 304307 : block = ItemPointerGetBlockNumber(otid);
3355 : : INJECTION_POINT("heap_update-before-pin", NULL);
3356 : 304307 : buffer = ReadBuffer(relation, block);
3478 kgrittn@postgresql.o 3357 : 304307 : page = BufferGetPage(buffer);
3358 : :
3359 : : /*
3360 : : * Before locking the buffer, pin the visibility map page if it appears to
3361 : : * be necessary. Since we haven't got the lock yet, someone else might be
3362 : : * in the middle of changing this, so we'll need to recheck after we have
3363 : : * the lock.
3364 : : */
5243 rhaas@postgresql.org 3365 [ + + ]: 304307 : if (PageIsAllVisible(page))
3366 : 1639 : visibilitymap_pin(relation, block, &vmbuffer);
3367 : :
9814 vadim4o@yahoo.com 3368 : 304307 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
3369 : :
6316 tgl@sss.pgh.pa.us 3370 : 304307 : lp = PageGetItemId(page, ItemPointerGetOffsetNumber(otid));
3371 : :
3372 : : /*
3373 : : * Usually, a buffer pin and/or snapshot blocks pruning of otid, ensuring
3374 : : * we see LP_NORMAL here. When the otid origin is a syscache, we may have
3375 : : * neither a pin nor a snapshot. Hence, we may see other LP_ states, each
3376 : : * of which indicates concurrent pruning.
3377 : : *
3378 : : * Failing with TM_Updated would be most accurate. However, unlike other
3379 : : * TM_Updated scenarios, we don't know the successor ctid in LP_UNUSED and
3380 : : * LP_DEAD cases. While the distinction between TM_Updated and TM_Deleted
3381 : : * does matter to SQL statements UPDATE and MERGE, those SQL statements
3382 : : * hold a snapshot that ensures LP_NORMAL. Hence, the choice between
3383 : : * TM_Updated and TM_Deleted affects only the wording of error messages.
3384 : : * Settle on TM_Deleted, for two reasons. First, it avoids complicating
3385 : : * the specification of when tmfd->ctid is valid. Second, it creates
3386 : : * error log evidence that we took this branch.
3387 : : *
3388 : : * Since it's possible to see LP_UNUSED at otid, it's also possible to see
3389 : : * LP_NORMAL for a tuple that replaced LP_UNUSED. If it's a tuple for an
3390 : : * unrelated row, we'll fail with "duplicate key value violates unique".
3391 : : * XXX if otid is the live, newer version of the newtup row, we'll discard
3392 : : * changes originating in versions of this catalog row after the version
3393 : : * the caller got from syscache. See syscache-update-pruned.spec.
3394 : : */
276 noah@leadboat.com 3395 [ - + ]: 304307 : if (!ItemIdIsNormal(lp))
3396 : : {
276 noah@leadboat.com 3397 [ # # ]:UBC 0 : Assert(RelationSupportsSysCache(RelationGetRelid(relation)));
3398 : :
3399 : 0 : UnlockReleaseBuffer(buffer);
3400 [ # # ]: 0 : Assert(!have_tuple_lock);
3401 [ # # ]: 0 : if (vmbuffer != InvalidBuffer)
3402 : 0 : ReleaseBuffer(vmbuffer);
3403 : 0 : tmfd->ctid = *otid;
3404 : 0 : tmfd->xmax = InvalidTransactionId;
3405 : 0 : tmfd->cmax = InvalidCommandId;
3406 : 0 : *update_indexes = TU_None;
3407 : :
3408 : 0 : bms_free(hot_attrs);
3409 : 0 : bms_free(sum_attrs);
3410 : 0 : bms_free(key_attrs);
3411 : 0 : bms_free(id_attrs);
3412 : : /* modified_attrs not yet initialized */
3413 : 0 : bms_free(interesting_attrs);
3414 : 0 : return TM_Deleted;
3415 : : }
3416 : :
3417 : : /*
3418 : : * Fill in enough data in oldtup for HeapDetermineColumnsInfo to work
3419 : : * properly.
3420 : : */
4652 alvherre@alvh.no-ip. 3421 :CBC 304307 : oldtup.t_tableOid = RelationGetRelid(relation);
6316 tgl@sss.pgh.pa.us 3422 : 304307 : oldtup.t_data = (HeapTupleHeader) PageGetItem(page, lp);
9832 vadim4o@yahoo.com 3423 : 304307 : oldtup.t_len = ItemIdGetLength(lp);
3424 : 304307 : oldtup.t_self = *otid;
3425 : :
3426 : : /* the new tuple is ready, except for this: */
4652 alvherre@alvh.no-ip. 3427 : 304307 : newtup->t_tableOid = RelationGetRelid(relation);
3428 : :
3429 : : /*
3430 : : * Determine columns modified by the update. Additionally, identify
3431 : : * whether any of the unmodified replica identity key attributes in the
3432 : : * old tuple is externally stored or not. This is required because for
3433 : : * such attributes the flattened value won't be WAL logged as part of the
3434 : : * new tuple so we must include it as part of the old_key_tuple. See
3435 : : * ExtractReplicaIdentity.
3436 : : */
1352 akapila@postgresql.o 3437 : 304307 : modified_attrs = HeapDetermineColumnsInfo(relation, interesting_attrs,
3438 : : id_attrs, &oldtup,
3439 : : newtup, &id_has_external);
3440 : :
3441 : : /*
3442 : : * If we're not updating any "key" column, we can grab a weaker lock type.
3443 : : * This allows for more concurrency when we are running simultaneously
3444 : : * with foreign key checks.
3445 : : *
3446 : : * Note that if a column gets detoasted while executing the update, but
3447 : : * the value ends up being the same, this test will fail and we will use
3448 : : * the stronger lock. This is acceptable; the important case to optimize
3449 : : * is updates that don't manipulate key columns, not those that
3450 : : * serendipitously arrive at the same key values.
3451 : : */
3135 alvherre@alvh.no-ip. 3452 [ + + ]: 304307 : if (!bms_overlap(modified_attrs, key_attrs))
3453 : : {
2756 simon@2ndQuadrant.co 3454 : 300146 : *lockmode = LockTupleNoKeyExclusive;
4661 alvherre@alvh.no-ip. 3455 : 300146 : mxact_status = MultiXactStatusNoKeyUpdate;
3456 : 300146 : key_intact = true;
3457 : :
3458 : : /*
3459 : : * If this is the first possibly-multixact-able operation in the
3460 : : * current transaction, set my per-backend OldestMemberMXactId
3461 : : * setting. We can be certain that the transaction will never become a
3462 : : * member of any older MultiXactIds than that. (We have to do this
3463 : : * even if we end up just using our own TransactionId below, since
3464 : : * some other backend could incorporate our XID into a MultiXact
3465 : : * immediately afterwards.)
3466 : : */
3467 : 300146 : MultiXactIdSetOldestMember();
3468 : : }
3469 : : else
3470 : : {
2756 simon@2ndQuadrant.co 3471 : 4161 : *lockmode = LockTupleExclusive;
4661 alvherre@alvh.no-ip. 3472 : 4161 : mxact_status = MultiXactStatusUpdate;
3473 : 4161 : key_intact = false;
3474 : : }
3475 : :
3476 : : /*
3477 : : * Note: beyond this point, use oldtup not otid to refer to old tuple.
3478 : : * otid may very well point at newtup->t_self, which we will overwrite
3479 : : * with the new tuple's location, so there's great risk of confusion if we
3480 : : * use otid anymore.
3481 : : */
3482 : :
9814 vadim4o@yahoo.com 3483 : 1 : l2:
4661 alvherre@alvh.no-ip. 3484 : 304308 : checked_lockers = false;
3485 : 304308 : locker_remains = false;
4481 rhaas@postgresql.org 3486 : 304308 : result = HeapTupleSatisfiesUpdate(&oldtup, cid, buffer);
3487 : :
3488 : : /* see below about the "no wait" case */
565 akorotkov@postgresql 3489 [ + + - + ]: 304308 : Assert(result != TM_BeingModified || wait);
3490 : :
2411 andres@anarazel.de 3491 [ - + ]: 304308 : if (result == TM_Invisible)
3492 : : {
7151 tgl@sss.pgh.pa.us 3493 :UBC 0 : UnlockReleaseBuffer(buffer);
3740 3494 [ # # ]: 0 : ereport(ERROR,
3495 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
3496 : : errmsg("attempted to update invisible tuple")));
3497 : : }
565 akorotkov@postgresql 3498 [ + + + - ]:CBC 304308 : else if (result == TM_BeingModified && wait)
3499 : : {
3500 : : TransactionId xwait;
3501 : : uint16 infomask;
4661 alvherre@alvh.no-ip. 3502 : 35974 : bool can_continue = false;
3503 : :
3504 : : /*
3505 : : * XXX note that we don't consider the "no wait" case here. This
3506 : : * isn't a problem currently because no caller uses that case, but it
3507 : : * should be fixed if such a caller is introduced. It wasn't a
3508 : : * problem previously because this code would always wait, but now
3509 : : * that some tuple locks do not conflict with one of the lock modes we
3510 : : * use, it is possible that this case is interesting to handle
3511 : : * specially.
3512 : : *
3513 : : * This may cause failures with third-party code that calls
3514 : : * heap_update directly.
3515 : : */
3516 : :
3517 : : /* must copy state data before unlocking buffer */
3518 : 35974 : xwait = HeapTupleHeaderGetRawXmax(oldtup.t_data);
7486 tgl@sss.pgh.pa.us 3519 : 35974 : infomask = oldtup.t_data->t_infomask;
3520 : :
3521 : : /*
3522 : : * Now we have to do something about the existing locker. If it's a
3523 : : * multi, sleep on it; we might be awakened before it is completely
3524 : : * gone (or even not sleep at all in some cases); we need to preserve
3525 : : * it as locker, unless it is gone completely.
3526 : : *
3527 : : * If it's not a multi, we need to check for sleeping conditions
3528 : : * before actually going to sleep. If the update doesn't conflict
3529 : : * with the locks, we just continue without sleeping (but making sure
3530 : : * it is preserved).
3531 : : *
3532 : : * Before sleeping, we need to acquire tuple lock to establish our
3533 : : * priority for the tuple (see heap_lock_tuple). LockTuple will
3534 : : * release us when we are next-in-line for the tuple. Note we must
3535 : : * not acquire the tuple lock until we're sure we're going to sleep;
3536 : : * otherwise we're open for race conditions with other transactions
3537 : : * holding the tuple lock which sleep on us.
3538 : : *
3539 : : * If we are forced to "start over" below, we keep the tuple lock;
3540 : : * this arranges that we stay at the head of the line while rechecking
3541 : : * tuple state.
3542 : : */
7488 3543 [ + + ]: 35974 : if (infomask & HEAP_XMAX_IS_MULTI)
3544 : : {
3545 : : TransactionId update_xact;
3546 : : int remain;
2324 alvherre@alvh.no-ip. 3547 : 60 : bool current_is_member = false;
3548 : :
3854 3549 [ + + ]: 60 : if (DoesMultiXactIdConflict((MultiXactId) xwait, infomask,
3550 : : *lockmode, ¤t_is_member))
3551 : : {
3552 : 8 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
3553 : :
3554 : : /*
3555 : : * Acquire the lock, if necessary (but skip it when we're
3556 : : * requesting a lock and already have one; avoids deadlock).
3557 : : */
2324 3558 [ - + ]: 8 : if (!current_is_member)
2324 alvherre@alvh.no-ip. 3559 :UBC 0 : heap_acquire_tuplock(relation, &(oldtup.t_self), *lockmode,
3560 : : LockWaitBlock, &have_tuple_lock);
3561 : :
3562 : : /* wait for multixact */
3854 alvherre@alvh.no-ip. 3563 :CBC 8 : MultiXactIdWait((MultiXactId) xwait, mxact_status, infomask,
3564 : : relation, &oldtup.t_self, XLTW_Update,
3565 : : &remain);
3566 : 8 : checked_lockers = true;
3567 : 8 : locker_remains = remain != 0;
3568 : 8 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
3569 : :
3570 : : /*
3571 : : * If xwait had just locked the tuple then some other xact
3572 : : * could update this tuple before we get to this point. Check
3573 : : * for xmax change, and start over if so.
3574 : : */
3575 [ + - ]: 8 : if (xmax_infomask_changed(oldtup.t_data->t_infomask,
3576 [ - + ]: 8 : infomask) ||
3051 tgl@sss.pgh.pa.us 3577 : 8 : !TransactionIdEquals(HeapTupleHeaderGetRawXmax(oldtup.t_data),
3578 : : xwait))
3854 alvherre@alvh.no-ip. 3579 :UBC 0 : goto l2;
3580 : : }
3581 : :
3582 : : /*
3583 : : * Note that the multixact may not be done by now. It could have
3584 : : * surviving members; our own xact or other subxacts of this
3585 : : * backend, and also any other concurrent transaction that locked
3586 : : * the tuple with LockTupleKeyShare if we only got
3587 : : * LockTupleNoKeyExclusive. If this is the case, we have to be
3588 : : * careful to mark the updated tuple with the surviving members in
3589 : : * Xmax.
3590 : : *
3591 : : * Note that there could have been another update in the
3592 : : * MultiXact. In that case, we need to check whether it committed
3593 : : * or aborted. If it aborted we are safe to update it again;
3594 : : * otherwise there is an update conflict, and we have to return
3595 : : * TableTuple{Deleted, Updated} below.
3596 : : *
3597 : : * In the LockTupleExclusive case, we still need to preserve the
3598 : : * surviving members: those would include the tuple locks we had
3599 : : * before this one, which are important to keep in case this
3600 : : * subxact aborts.
3601 : : */
4661 alvherre@alvh.no-ip. 3602 [ + + ]:CBC 60 : if (!HEAP_XMAX_IS_LOCKED_ONLY(oldtup.t_data->t_infomask))
3603 : 8 : update_xact = HeapTupleGetUpdateXid(oldtup.t_data);
3604 : : else
3854 3605 : 52 : update_xact = InvalidTransactionId;
3606 : :
3607 : : /*
3608 : : * There was no UPDATE in the MultiXact; or it aborted. No
3609 : : * TransactionIdIsInProgress() call needed here, since we called
3610 : : * MultiXactIdWait() above.
3611 : : */
4661 3612 [ + + + + ]: 68 : if (!TransactionIdIsValid(update_xact) ||
3613 : 8 : TransactionIdDidAbort(update_xact))
3614 : 53 : can_continue = true;
3615 : : }
3854 3616 [ + + ]: 35914 : else if (TransactionIdIsCurrentTransactionId(xwait))
3617 : : {
3618 : : /*
3619 : : * The only locker is ourselves; we can avoid grabbing the tuple
3620 : : * lock here, but must preserve our locking information.
3621 : : */
3622 : 35808 : checked_lockers = true;
3623 : 35808 : locker_remains = true;
3624 : 35808 : can_continue = true;
3625 : : }
3626 [ + + + + ]: 106 : else if (HEAP_XMAX_IS_KEYSHR_LOCKED(infomask) && key_intact)
3627 : : {
3628 : : /*
3629 : : * If it's just a key-share locker, and we're not changing the key
3630 : : * columns, we don't need to wait for it to end; but we need to
3631 : : * preserve it as locker.
3632 : : */
3633 : 29 : checked_lockers = true;
3634 : 29 : locker_remains = true;
3635 : 29 : can_continue = true;
3636 : : }
3637 : : else
3638 : : {
3639 : : /*
3640 : : * Wait for regular transaction to end; but first, acquire tuple
3641 : : * lock.
3642 : : */
3643 : 77 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
2756 simon@2ndQuadrant.co 3644 : 77 : heap_acquire_tuplock(relation, &(oldtup.t_self), *lockmode,
3645 : : LockWaitBlock, &have_tuple_lock);
3854 alvherre@alvh.no-ip. 3646 : 77 : XactLockTableWait(xwait, relation, &oldtup.t_self,
3647 : : XLTW_Update);
3648 : 77 : checked_lockers = true;
3649 : 77 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
3650 : :
3651 : : /*
3652 : : * xwait is done, but if xwait had just locked the tuple then some
3653 : : * other xact could update this tuple before we get to this point.
3654 : : * Check for xmax change, and start over if so.
3655 : : */
3656 [ + + - + ]: 153 : if (xmax_infomask_changed(oldtup.t_data->t_infomask, infomask) ||
3657 : 76 : !TransactionIdEquals(xwait,
3658 : : HeapTupleHeaderGetRawXmax(oldtup.t_data)))
3659 : 1 : goto l2;
3660 : :
3661 : : /* Otherwise check if it committed or aborted */
3662 : 76 : UpdateXmaxHintBits(oldtup.t_data, buffer, xwait);
3663 [ + + ]: 76 : if (oldtup.t_data->t_infomask & HEAP_XMAX_INVALID)
4661 3664 : 22 : can_continue = true;
3665 : : }
3666 : :
2411 andres@anarazel.de 3667 [ + + ]: 35973 : if (can_continue)
3668 : 35912 : result = TM_Ok;
1709 alvherre@alvh.no-ip. 3669 [ + + ]: 61 : else if (!ItemPointerEquals(&oldtup.t_self, &oldtup.t_data->t_ctid))
2411 andres@anarazel.de 3670 : 56 : result = TM_Updated;
3671 : : else
3672 : 5 : result = TM_Deleted;
3673 : : }
3674 : :
3675 : : /* Sanity check the result HeapTupleSatisfiesUpdate() and the logic above */
3676 [ + + ]: 304307 : if (result != TM_Ok)
3677 : : {
3678 [ + + + + : 157 : Assert(result == TM_SelfModified ||
- + - - ]
3679 : : result == TM_Updated ||
3680 : : result == TM_Deleted ||
3681 : : result == TM_BeingModified);
7374 tgl@sss.pgh.pa.us 3682 [ - + ]: 157 : Assert(!(oldtup.t_data->t_infomask & HEAP_XMAX_INVALID));
2411 andres@anarazel.de 3683 [ + + - + ]: 157 : Assert(result != TM_Updated ||
3684 : : !ItemPointerEquals(&oldtup.t_self, &oldtup.t_data->t_ctid));
3685 : : }
3686 : :
700 heikki.linnakangas@i 3687 [ + + + - ]: 304307 : if (crosscheck != InvalidSnapshot && result == TM_Ok)
3688 : : {
3689 : : /* Perform additional check for transaction-snapshot mode RI updates */
3690 [ + - ]: 1 : if (!HeapTupleSatisfiesVisibility(&oldtup, crosscheck, buffer))
3691 : 1 : result = TM_Updated;
3692 : : }
3693 : :
3694 [ + + ]: 304307 : if (result != TM_Ok)
3695 : : {
2411 andres@anarazel.de 3696 : 158 : tmfd->ctid = oldtup.t_data->t_ctid;
3697 : 158 : tmfd->xmax = HeapTupleHeaderGetUpdateXid(oldtup.t_data);
3698 [ + + ]: 158 : if (result == TM_SelfModified)
3699 : 52 : tmfd->cmax = HeapTupleHeaderGetCmax(oldtup.t_data);
3700 : : else
3701 : 106 : tmfd->cmax = InvalidCommandId;
565 akorotkov@postgresql 3702 : 158 : UnlockReleaseBuffer(buffer);
7486 tgl@sss.pgh.pa.us 3703 [ + + ]: 158 : if (have_tuple_lock)
2756 simon@2ndQuadrant.co 3704 : 54 : UnlockTupleTuplock(relation, &(oldtup.t_self), *lockmode);
5243 rhaas@postgresql.org 3705 [ - + ]: 158 : if (vmbuffer != InvalidBuffer)
5243 rhaas@postgresql.org 3706 :UBC 0 : ReleaseBuffer(vmbuffer);
953 tomas.vondra@postgre 3707 :CBC 158 : *update_indexes = TU_None;
3708 : :
6613 tgl@sss.pgh.pa.us 3709 : 158 : bms_free(hot_attrs);
953 tomas.vondra@postgre 3710 : 158 : bms_free(sum_attrs);
4661 alvherre@alvh.no-ip. 3711 : 158 : bms_free(key_attrs);
3352 tgl@sss.pgh.pa.us 3712 : 158 : bms_free(id_attrs);
3135 alvherre@alvh.no-ip. 3713 : 158 : bms_free(modified_attrs);
3714 : 158 : bms_free(interesting_attrs);
9814 vadim4o@yahoo.com 3715 : 158 : return result;
3716 : : }
3717 : :
3718 : : /*
3719 : : * If we didn't pin the visibility map page and the page has become all
3720 : : * visible while we were busy locking the buffer, or during some
3721 : : * subsequent window during which we had it unlocked, we'll have to unlock
3722 : : * and re-lock, to avoid holding the buffer lock across an I/O. That's a
3723 : : * bit unfortunate, especially since we'll now have to recheck whether the
3724 : : * tuple has been locked or updated under us, but hopefully it won't
3725 : : * happen very often.
3726 : : */
5237 rhaas@postgresql.org 3727 [ + + - + ]: 304149 : if (vmbuffer == InvalidBuffer && PageIsAllVisible(page))
3728 : : {
5237 rhaas@postgresql.org 3729 :UBC 0 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
3730 : 0 : visibilitymap_pin(relation, block, &vmbuffer);
3731 : 0 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
5145 3732 : 0 : goto l2;
3733 : : }
3734 : :
3735 : : /* Fill in transaction status data */
3736 : :
3737 : : /*
3738 : : * If the tuple we're updating is locked, we need to preserve the locking
3739 : : * info in the old tuple's Xmax. Prepare a new Xmax value for this.
3740 : : */
4661 alvherre@alvh.no-ip. 3741 :CBC 304149 : compute_new_xmax_infomask(HeapTupleHeaderGetRawXmax(oldtup.t_data),
3742 : 304149 : oldtup.t_data->t_infomask,
3743 : 304149 : oldtup.t_data->t_infomask2,
3744 : : xid, *lockmode, true,
3745 : : &xmax_old_tuple, &infomask_old_tuple,
3746 : : &infomask2_old_tuple);
3747 : :
3748 : : /*
3749 : : * And also prepare an Xmax value for the new copy of the tuple. If there
3750 : : * was no xmax previously, or there was one but all lockers are now gone,
3751 : : * then use InvalidTransactionId; otherwise, get the xmax from the old
3752 : : * tuple. (In rare cases that might also be InvalidTransactionId and yet
3753 : : * not have the HEAP_XMAX_INVALID bit set; that's fine.)
3754 : : */
3755 [ + + + - ]: 340039 : if ((oldtup.t_data->t_infomask & HEAP_XMAX_INVALID) ||
3413 3756 [ + + ]: 71780 : HEAP_LOCKED_UPGRADED(oldtup.t_data->t_infomask) ||
4661 3757 [ - + ]: 35838 : (checked_lockers && !locker_remains))
3758 : 268259 : xmax_new_tuple = InvalidTransactionId;
3759 : : else
3760 : 35890 : xmax_new_tuple = HeapTupleHeaderGetRawXmax(oldtup.t_data);
3761 : :
3762 [ + + ]: 304149 : if (!TransactionIdIsValid(xmax_new_tuple))
3763 : : {
3764 : 268259 : infomask_new_tuple = HEAP_XMAX_INVALID;
3765 : 268259 : infomask2_new_tuple = 0;
3766 : : }
3767 : : else
3768 : : {
3769 : : /*
3770 : : * If we found a valid Xmax for the new tuple, then the infomask bits
3771 : : * to use on the new tuple depend on what was there on the old one.
3772 : : * Note that since we're doing an update, the only possibility is that
3773 : : * the lockers had FOR KEY SHARE lock.
3774 : : */
3775 [ + + ]: 35890 : if (oldtup.t_data->t_infomask & HEAP_XMAX_IS_MULTI)
3776 : : {
3777 : 53 : GetMultiXactIdHintBits(xmax_new_tuple, &infomask_new_tuple,
3778 : : &infomask2_new_tuple);
3779 : : }
3780 : : else
3781 : : {
3782 : 35837 : infomask_new_tuple = HEAP_XMAX_KEYSHR_LOCK | HEAP_XMAX_LOCK_ONLY;
3783 : 35837 : infomask2_new_tuple = 0;
3784 : : }
3785 : : }
3786 : :
3787 : : /*
3788 : : * Prepare the new tuple with the appropriate initial values of Xmin and
3789 : : * Xmax, as well as initial infomask bits as computed above.
3790 : : */
9832 vadim4o@yahoo.com 3791 : 304149 : newtup->t_data->t_infomask &= ~(HEAP_XACT_MASK);
6613 tgl@sss.pgh.pa.us 3792 : 304149 : newtup->t_data->t_infomask2 &= ~(HEAP2_XACT_MASK);
7712 3793 : 304149 : HeapTupleHeaderSetXmin(newtup->t_data, xid);
8536 bruce@momjian.us 3794 : 304149 : HeapTupleHeaderSetCmin(newtup->t_data, cid);
4661 alvherre@alvh.no-ip. 3795 : 304149 : newtup->t_data->t_infomask |= HEAP_UPDATED | infomask_new_tuple;
3796 : 304149 : newtup->t_data->t_infomask2 |= infomask2_new_tuple;
3797 : 304149 : HeapTupleHeaderSetXmax(newtup->t_data, xmax_new_tuple);
3798 : :
3799 : : /*
3800 : : * Replace cid with a combo CID if necessary. Note that we already put
3801 : : * the plain cid into the new tuple.
3802 : : */
6836 tgl@sss.pgh.pa.us 3803 : 304149 : HeapTupleHeaderAdjustCmax(oldtup.t_data, &cid, &iscombo);
3804 : :
3805 : : /*
3806 : : * If the toaster needs to be activated, OR if the new tuple will not fit
3807 : : * on the same page as the old, then we need to release the content lock
3808 : : * (but not the pin!) on the old tuple's buffer while we are off doing
3809 : : * TOAST and/or table-file-extension work. We must mark the old tuple to
3810 : : * show that it's locked, else other processes may try to update it
3811 : : * themselves.
3812 : : *
3813 : : * We need to invoke the toaster if there are already any out-of-line
3814 : : * toasted values present, or if the new tuple is over-threshold.
3815 : : */
4622 kgrittn@postgresql.o 3816 [ - + ]: 304149 : if (relation->rd_rel->relkind != RELKIND_RELATION &&
4622 kgrittn@postgresql.o 3817 [ # # ]:UBC 0 : relation->rd_rel->relkind != RELKIND_MATVIEW)
3818 : : {
3819 : : /* toast table entries should never be recursively toasted */
6783 tgl@sss.pgh.pa.us 3820 [ # # ]: 0 : Assert(!HeapTupleHasExternal(&oldtup));
3821 [ # # ]: 0 : Assert(!HeapTupleHasExternal(newtup));
3822 : 0 : need_toast = false;
3823 : : }
3824 : : else
6783 tgl@sss.pgh.pa.us 3825 [ + + ]:CBC 912075 : need_toast = (HeapTupleHasExternal(&oldtup) ||
3826 [ + + ]: 607926 : HeapTupleHasExternal(newtup) ||
3827 [ + + ]: 303753 : newtup->t_len > TOAST_TUPLE_THRESHOLD);
3828 : :
6316 3829 : 304149 : pagefree = PageGetHeapFreeSpace(page);
3830 : :
6841 3831 : 304149 : newtupsize = MAXALIGN(newtup->t_len);
3832 : :
8931 3833 [ + + + + ]: 304149 : if (need_toast || newtupsize > pagefree)
9182 vadim4o@yahoo.com 3834 : 149348 : {
3835 : : TransactionId xmax_lock_old_tuple;
3836 : : uint16 infomask_lock_old_tuple,
3837 : : infomask2_lock_old_tuple;
3389 andres@anarazel.de 3838 : 149348 : bool cleared_all_frozen = false;
3839 : :
3840 : : /*
3841 : : * To prevent concurrent sessions from updating the tuple, we have to
3842 : : * temporarily mark it locked, while we release the page-level lock.
3843 : : *
3844 : : * To satisfy the rule that any xid potentially appearing in a buffer
3845 : : * written out to disk, we unfortunately have to WAL log this
3846 : : * temporary modification. We can reuse xl_heap_lock for this
3847 : : * purpose. If we crash/error before following through with the
3848 : : * actual update, xmax will be of an aborted transaction, allowing
3849 : : * other sessions to proceed.
3850 : : */
3851 : :
3852 : : /*
3853 : : * Compute xmax / infomask appropriate for locking the tuple. This has
3854 : : * to be done separately from the combo that's going to be used for
3855 : : * updating, because the potentially created multixact would otherwise
3856 : : * be wrong.
3857 : : */
3392 3858 : 149348 : compute_new_xmax_infomask(HeapTupleHeaderGetRawXmax(oldtup.t_data),
3859 : 149348 : oldtup.t_data->t_infomask,
3860 : 149348 : oldtup.t_data->t_infomask2,
3861 : : xid, *lockmode, false,
3862 : : &xmax_lock_old_tuple, &infomask_lock_old_tuple,
3863 : : &infomask2_lock_old_tuple);
3864 : :
3865 [ - + ]: 149348 : Assert(HEAP_XMAX_IS_LOCKED_ONLY(infomask_lock_old_tuple));
3866 : :
3867 : 149348 : START_CRIT_SECTION();
3868 : :
3869 : : /* Clear obsolete visibility flags ... */
4661 alvherre@alvh.no-ip. 3870 : 149348 : oldtup.t_data->t_infomask &= ~(HEAP_XMAX_BITS | HEAP_MOVED);
3871 : 149348 : oldtup.t_data->t_infomask2 &= ~HEAP_KEYS_UPDATED;
6613 tgl@sss.pgh.pa.us 3872 : 149348 : HeapTupleClearHotUpdated(&oldtup);
3873 : : /* ... and store info about transaction updating this tuple */
3392 andres@anarazel.de 3874 [ - + ]: 149348 : Assert(TransactionIdIsValid(xmax_lock_old_tuple));
3875 : 149348 : HeapTupleHeaderSetXmax(oldtup.t_data, xmax_lock_old_tuple);
3876 : 149348 : oldtup.t_data->t_infomask |= infomask_lock_old_tuple;
3877 : 149348 : oldtup.t_data->t_infomask2 |= infomask2_lock_old_tuple;
6836 tgl@sss.pgh.pa.us 3878 : 149348 : HeapTupleHeaderSetCmax(oldtup.t_data, cid, iscombo);
3879 : :
3880 : : /* temporarily make it look not-updated, but locked */
7282 3881 : 149348 : oldtup.t_data->t_ctid = oldtup.t_self;
3882 : :
3883 : : /*
3884 : : * Clear all-frozen bit on visibility map if needed. We could
3885 : : * immediately reset ALL_VISIBLE, but given that the WAL logging
3886 : : * overhead would be unchanged, that doesn't seem necessarily
3887 : : * worthwhile.
3888 : : */
1659 3889 [ + + + + ]: 150226 : if (PageIsAllVisible(page) &&
3389 andres@anarazel.de 3890 : 878 : visibilitymap_clear(relation, block, vmbuffer,
3891 : : VISIBILITYMAP_ALL_FROZEN))
3892 : 682 : cleared_all_frozen = true;
3893 : :
3392 3894 : 149348 : MarkBufferDirty(buffer);
3895 : :
3896 [ + + + + : 149348 : if (RelationNeedsWAL(relation))
+ - + + ]
3897 : : {
3898 : : xl_heap_lock xlrec;
3899 : : XLogRecPtr recptr;
3900 : :
3901 : 139217 : XLogBeginInsert();
3902 : 139217 : XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
3903 : :
3904 : 139217 : xlrec.offnum = ItemPointerGetOffsetNumber(&oldtup.t_self);
931 pg@bowt.ie 3905 : 139217 : xlrec.xmax = xmax_lock_old_tuple;
3392 andres@anarazel.de 3906 : 278434 : xlrec.infobits_set = compute_infobits(oldtup.t_data->t_infomask,
3907 : 139217 : oldtup.t_data->t_infomask2);
3389 3908 : 139217 : xlrec.flags =
3909 : 139217 : cleared_all_frozen ? XLH_LOCK_ALL_FROZEN_CLEARED : 0;
259 peter@eisentraut.org 3910 : 139217 : XLogRegisterData(&xlrec, SizeOfHeapLock);
3392 andres@anarazel.de 3911 : 139217 : recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_LOCK);
3912 : 139217 : PageSetLSN(page, recptr);
3913 : : }
3914 : :
3915 [ - + ]: 149348 : END_CRIT_SECTION();
3916 : :
9182 vadim4o@yahoo.com 3917 : 149348 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
3918 : :
3919 : : /*
3920 : : * Let the toaster do its thing, if needed.
3921 : : *
3922 : : * Note: below this point, heaptup is the data we actually intend to
3923 : : * store into the relation; newtup is the caller's original untoasted
3924 : : * data.
3925 : : */
9052 tgl@sss.pgh.pa.us 3926 [ + + ]: 149348 : if (need_toast)
3927 : : {
3928 : : /* Note we always use WAL and FSM during updates */
2216 rhaas@postgresql.org 3929 : 1712 : heaptup = heap_toast_insert_or_update(relation, newtup, &oldtup, 0);
7282 tgl@sss.pgh.pa.us 3930 : 1712 : newtupsize = MAXALIGN(heaptup->t_len);
3931 : : }
3932 : : else
3933 : 147636 : heaptup = newtup;
3934 : :
3935 : : /*
3936 : : * Now, do we need a new page for the tuple, or not? This is a bit
3937 : : * tricky since someone else could have added tuples to the page while
3938 : : * we weren't looking. We have to recheck the available space after
3939 : : * reacquiring the buffer lock. But don't bother to do that if the
3940 : : * former amount of free space is still not enough; it's unlikely
3941 : : * there's more free now than before.
3942 : : *
3943 : : * What's more, if we need to get a new page, we will need to acquire
3944 : : * buffer locks on both old and new pages. To avoid deadlock against
3945 : : * some other backend trying to get the same two locks in the other
3946 : : * order, we must be consistent about the order we get the locks in.
3947 : : * We use the rule "lock the lower-numbered page of the relation
3948 : : * first". To implement this, we must do RelationGetBufferForTuple
3949 : : * while not holding the lock on the old page, and we must rely on it
3950 : : * to get the locks on both pages in the correct order.
3951 : : *
3952 : : * Another consideration is that we need visibility map page pin(s) if
3953 : : * we will have to clear the all-visible flag on either page. If we
3954 : : * call RelationGetBufferForTuple, we rely on it to acquire any such
3955 : : * pins; but if we don't, we have to handle that here. Hence we need
3956 : : * a loop.
3957 : : */
3958 : : for (;;)
3959 : : {
1659 3960 [ + + ]: 149348 : if (newtupsize > pagefree)
3961 : : {
3962 : : /* It doesn't fit, must use RelationGetBufferForTuple. */
3963 : 148824 : newbuf = RelationGetBufferForTuple(relation, heaptup->t_len,
3964 : : buffer, 0, NULL,
3965 : : &vmbuffer_new, &vmbuffer,
3966 : : 0);
3967 : : /* We're all done. */
3968 : 148824 : break;
3969 : : }
3970 : : /* Acquire VM page pin if needed and we don't have it. */
3971 [ + + - + ]: 524 : if (vmbuffer == InvalidBuffer && PageIsAllVisible(page))
1659 tgl@sss.pgh.pa.us 3972 :UBC 0 : visibilitymap_pin(relation, block, &vmbuffer);
3973 : : /* Re-acquire the lock on the old tuple's page. */
8931 tgl@sss.pgh.pa.us 3974 :CBC 524 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
3975 : : /* Re-check using the up-to-date free space */
6316 3976 : 524 : pagefree = PageGetHeapFreeSpace(page);
1659 3977 [ + - ]: 524 : if (newtupsize > pagefree ||
3978 [ + + - + ]: 524 : (vmbuffer == InvalidBuffer && PageIsAllVisible(page)))
3979 : : {
3980 : : /*
3981 : : * Rats, it doesn't fit anymore, or somebody just now set the
3982 : : * all-visible flag. We must now unlock and loop to avoid
3983 : : * deadlock. Fortunately, this path should seldom be taken.
3984 : : */
8931 tgl@sss.pgh.pa.us 3985 :UBC 0 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
3986 : : }
3987 : : else
3988 : : {
3989 : : /* We're all done. */
8931 tgl@sss.pgh.pa.us 3990 :CBC 524 : newbuf = buffer;
1659 3991 : 524 : break;
3992 : : }
3993 : : }
3994 : : }
3995 : : else
3996 : : {
3997 : : /* No TOAST work needed, and it'll fit on same page */
9052 3998 : 154801 : newbuf = buffer;
7282 3999 : 154801 : heaptup = newtup;
4000 : : }
4001 : :
4002 : : /*
4003 : : * We're about to do the actual update -- check for conflict first, to
4004 : : * avoid possibly having to roll back work we've just done.
4005 : : *
4006 : : * This is safe without a recheck as long as there is no possibility of
4007 : : * another process scanning the pages between this check and the update
4008 : : * being visible to the scan (i.e., exclusive buffer content lock(s) are
4009 : : * continuously held from this point until the tuple update is visible).
4010 : : *
4011 : : * For the new tuple the only check needed is at the relation level, but
4012 : : * since both tuples are in the same relation and the check for oldtup
4013 : : * will include checking the relation level, there is no benefit to a
4014 : : * separate check for the new tuple.
4015 : : */
1659 tmunro@postgresql.or 4016 : 304149 : CheckForSerializableConflictIn(relation, &oldtup.t_self,
4017 : : BufferGetBlockNumber(buffer));
4018 : :
4019 : : /*
4020 : : * At this point newbuf and buffer are both pinned and locked, and newbuf
4021 : : * has enough space for the new tuple. If they are the same buffer, only
4022 : : * one pin is held.
4023 : : */
4024 : :
6613 tgl@sss.pgh.pa.us 4025 [ + + ]: 304137 : if (newbuf == buffer)
4026 : : {
4027 : : /*
4028 : : * Since the new tuple is going into the same page, we might be able
4029 : : * to do a HOT update. Check if any of the index columns have been
4030 : : * changed.
4031 : : */
1432 pg@bowt.ie 4032 [ + + ]: 155313 : if (!bms_overlap(modified_attrs, hot_attrs))
4033 : : {
6613 tgl@sss.pgh.pa.us 4034 : 143307 : use_hot_update = true;
4035 : :
4036 : : /*
4037 : : * If none of the columns that are used in hot-blocking indexes
4038 : : * were updated, we can apply HOT, but we do still need to check
4039 : : * if we need to update the summarizing indexes, and update those
4040 : : * indexes if the columns were updated, or we may fail to detect
4041 : : * e.g. value bound changes in BRIN minmax indexes.
4042 : : */
953 tomas.vondra@postgre 4043 [ + + ]: 143307 : if (bms_overlap(modified_attrs, sum_attrs))
4044 : 1641 : summarized_update = true;
4045 : : }
4046 : : }
4047 : : else
4048 : : {
4049 : : /* Set a hint that the old page could use prune/defrag */
6316 tgl@sss.pgh.pa.us 4050 : 148824 : PageSetFull(page);
4051 : : }
4052 : :
4053 : : /*
4054 : : * Compute replica identity tuple before entering the critical section so
4055 : : * we don't PANIC upon a memory allocation failure.
4056 : : * ExtractReplicaIdentity() will return NULL if nothing needs to be
4057 : : * logged. Pass old key required as true only if the replica identity key
4058 : : * columns are modified or it has external data.
4059 : : */
3135 alvherre@alvh.no-ip. 4060 : 304137 : old_key_tuple = ExtractReplicaIdentity(relation, &oldtup,
1352 akapila@postgresql.o 4061 [ + + + + ]: 304137 : bms_overlap(modified_attrs, id_attrs) ||
4062 : : id_has_external,
4063 : : &old_key_copied);
4064 : :
4065 : : /* NO EREPORT(ERROR) from here till changes are logged */
9055 tgl@sss.pgh.pa.us 4066 : 304137 : START_CRIT_SECTION();
4067 : :
4068 : : /*
4069 : : * If this transaction commits, the old tuple will become DEAD sooner or
4070 : : * later. Set flag that this page is a candidate for pruning once our xid
4071 : : * falls below the OldestXmin horizon. If the transaction finally aborts,
4072 : : * the subsequent page pruning will be a no-op and the hint will be
4073 : : * cleared.
4074 : : *
4075 : : * XXX Should we set hint on newbuf as well? If the transaction aborts,
4076 : : * there would be a prunable tuple in the newbuf; but for now we choose
4077 : : * not to optimize for aborts. Note that heap_xlog_update must be kept in
4078 : : * sync if this decision changes.
4079 : : */
6316 4080 [ - + + + : 304137 : PageSetPrunable(page, xid);
+ + ]
4081 : :
6613 4082 [ + + ]: 304137 : if (use_hot_update)
4083 : : {
4084 : : /* Mark the old tuple as HOT-updated */
4085 : 143307 : HeapTupleSetHotUpdated(&oldtup);
4086 : : /* And mark the new tuple as heap-only */
4087 : 143307 : HeapTupleSetHeapOnly(heaptup);
4088 : : /* Mark the caller's copy too, in case different from heaptup */
4089 : 143307 : HeapTupleSetHeapOnly(newtup);
4090 : : }
4091 : : else
4092 : : {
4093 : : /* Make sure tuples are correctly marked as not-HOT */
4094 : 160830 : HeapTupleClearHotUpdated(&oldtup);
4095 : 160830 : HeapTupleClearHeapOnly(heaptup);
4096 : 160830 : HeapTupleClearHeapOnly(newtup);
4097 : : }
4098 : :
3051 4099 : 304137 : RelationPutHeapTuple(relation, newbuf, heaptup, false); /* insert new tuple */
4100 : :
4101 : :
4102 : : /* Clear obsolete visibility flags, possibly set by ourselves above... */
3392 andres@anarazel.de 4103 : 304137 : oldtup.t_data->t_infomask &= ~(HEAP_XMAX_BITS | HEAP_MOVED);
4104 : 304137 : oldtup.t_data->t_infomask2 &= ~HEAP_KEYS_UPDATED;
4105 : : /* ... and store info about transaction updating this tuple */
4106 [ - + ]: 304137 : Assert(TransactionIdIsValid(xmax_old_tuple));
4107 : 304137 : HeapTupleHeaderSetXmax(oldtup.t_data, xmax_old_tuple);
4108 : 304137 : oldtup.t_data->t_infomask |= infomask_old_tuple;
4109 : 304137 : oldtup.t_data->t_infomask2 |= infomask2_old_tuple;
4110 : 304137 : HeapTupleHeaderSetCmax(oldtup.t_data, cid, iscombo);
4111 : :
4112 : : /* record address of new tuple in t_ctid of old one */
7282 tgl@sss.pgh.pa.us 4113 : 304137 : oldtup.t_data->t_ctid = heaptup->t_self;
4114 : :
4115 : : /* clear PD_ALL_VISIBLE flags, reset all visibilitymap bits */
3478 kgrittn@postgresql.o 4116 [ + + ]: 304137 : if (PageIsAllVisible(BufferGetPage(buffer)))
4117 : : {
5909 tgl@sss.pgh.pa.us 4118 : 1639 : all_visible_cleared = true;
3478 kgrittn@postgresql.o 4119 : 1639 : PageClearAllVisible(BufferGetPage(buffer));
5237 rhaas@postgresql.org 4120 : 1639 : visibilitymap_clear(relation, BufferGetBlockNumber(buffer),
4121 : : vmbuffer, VISIBILITYMAP_VALID_BITS);
4122 : : }
3478 kgrittn@postgresql.o 4123 [ + + + + ]: 304137 : if (newbuf != buffer && PageIsAllVisible(BufferGetPage(newbuf)))
4124 : : {
5909 tgl@sss.pgh.pa.us 4125 : 1000 : all_visible_cleared_new = true;
3478 kgrittn@postgresql.o 4126 : 1000 : PageClearAllVisible(BufferGetPage(newbuf));
5237 rhaas@postgresql.org 4127 : 1000 : visibilitymap_clear(relation, BufferGetBlockNumber(newbuf),
4128 : : vmbuffer_new, VISIBILITYMAP_VALID_BITS);
4129 : : }
4130 : :
7151 tgl@sss.pgh.pa.us 4131 [ + + ]: 304137 : if (newbuf != buffer)
4132 : 148824 : MarkBufferDirty(newbuf);
4133 : 304137 : MarkBufferDirty(buffer);
4134 : :
4135 : : /* XLOG stuff */
5433 rhaas@postgresql.org 4136 [ + + + + : 304137 : if (RelationNeedsWAL(relation))
+ + + + ]
4137 : : {
4138 : : XLogRecPtr recptr;
4139 : :
4140 : : /*
4141 : : * For logical decoding we need combo CIDs to properly decode the
4142 : : * catalog.
4143 : : */
4340 4144 [ + + + - : 292772 : if (RelationIsAccessibleInLogicalDecoding(relation))
- + - - -
- + + - +
- - - - -
- ]
4145 : : {
4146 : 2541 : log_heap_new_cid(relation, &oldtup);
4147 : 2541 : log_heap_new_cid(relation, heaptup);
4148 : : }
4149 : :
4150 : 292772 : recptr = log_heap_update(relation, buffer,
4151 : : newbuf, &oldtup, heaptup,
4152 : : old_key_tuple,
4153 : : all_visible_cleared,
4154 : : all_visible_cleared_new);
9248 vadim4o@yahoo.com 4155 [ + + ]: 292772 : if (newbuf != buffer)
4156 : : {
3478 kgrittn@postgresql.o 4157 : 138699 : PageSetLSN(BufferGetPage(newbuf), recptr);
4158 : : }
4159 : 292772 : PageSetLSN(BufferGetPage(buffer), recptr);
4160 : : }
4161 : :
9055 tgl@sss.pgh.pa.us 4162 [ - + ]: 304137 : END_CRIT_SECTION();
4163 : :
9248 vadim4o@yahoo.com 4164 [ + + ]: 304137 : if (newbuf != buffer)
4165 : 148824 : LockBuffer(newbuf, BUFFER_LOCK_UNLOCK);
9814 4166 : 304137 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
4167 : :
4168 : : /*
4169 : : * Mark old tuple for invalidation from system caches at next command
4170 : : * boundary, and mark the new tuple for invalidation in case we abort. We
4171 : : * have to do this before releasing the buffer because oldtup is in the
4172 : : * buffer. (heaptup is all in local memory, but it's necessary to process
4173 : : * both tuple versions in one call to inval.c so we can avoid redundant
4174 : : * sinval messages.)
4175 : : */
5187 tgl@sss.pgh.pa.us 4176 : 304137 : CacheInvalidateHeapTuple(relation, &oldtup, heaptup);
4177 : :
4178 : : /* Now we can release the buffer(s) */
9060 4179 [ + + ]: 304137 : if (newbuf != buffer)
7151 4180 : 148824 : ReleaseBuffer(newbuf);
565 akorotkov@postgresql 4181 : 304137 : ReleaseBuffer(buffer);
5243 rhaas@postgresql.org 4182 [ + + ]: 304137 : if (BufferIsValid(vmbuffer_new))
4183 : 1002 : ReleaseBuffer(vmbuffer_new);
4184 [ + + ]: 304137 : if (BufferIsValid(vmbuffer))
4185 : 1639 : ReleaseBuffer(vmbuffer);
4186 : :
4187 : : /*
4188 : : * Release the lmgr tuple lock, if we had it.
4189 : : */
7486 tgl@sss.pgh.pa.us 4190 [ + + ]: 304137 : if (have_tuple_lock)
2756 simon@2ndQuadrant.co 4191 : 22 : UnlockTupleTuplock(relation, &(oldtup.t_self), *lockmode);
4192 : :
950 pg@bowt.ie 4193 : 304137 : pgstat_count_heap_update(relation, use_hot_update, newbuf != buffer);
4194 : :
4195 : : /*
4196 : : * If heaptup is a private copy, release it. Don't forget to copy t_self
4197 : : * back to the caller's image, too.
4198 : : */
7282 tgl@sss.pgh.pa.us 4199 [ + + ]: 304137 : if (heaptup != newtup)
4200 : : {
4201 : 1664 : newtup->t_self = heaptup->t_self;
4202 : 1664 : heap_freetuple(heaptup);
4203 : : }
4204 : :
4205 : : /*
4206 : : * If it is a HOT update, the update may still need to update summarized
4207 : : * indexes, lest we fail to update those summaries and get incorrect
4208 : : * results (for example, minmax bounds of the block may change with this
4209 : : * update).
4210 : : */
953 tomas.vondra@postgre 4211 [ + + ]: 304137 : if (use_hot_update)
4212 : : {
4213 [ + + ]: 143307 : if (summarized_update)
4214 : 1641 : *update_indexes = TU_Summarizing;
4215 : : else
4216 : 141666 : *update_indexes = TU_None;
4217 : : }
4218 : : else
4219 : 160830 : *update_indexes = TU_All;
4220 : :
4340 rhaas@postgresql.org 4221 [ + + + + ]: 304137 : if (old_key_tuple != NULL && old_key_copied)
4222 : 84 : heap_freetuple(old_key_tuple);
4223 : :
6613 tgl@sss.pgh.pa.us 4224 : 304137 : bms_free(hot_attrs);
953 tomas.vondra@postgre 4225 : 304137 : bms_free(sum_attrs);
4661 alvherre@alvh.no-ip. 4226 : 304137 : bms_free(key_attrs);
3352 tgl@sss.pgh.pa.us 4227 : 304137 : bms_free(id_attrs);
3135 alvherre@alvh.no-ip. 4228 : 304137 : bms_free(modified_attrs);
4229 : 304137 : bms_free(interesting_attrs);
4230 : :
2411 andres@anarazel.de 4231 : 304137 : return TM_Ok;
4232 : : }
4233 : :
4234 : : #ifdef USE_ASSERT_CHECKING
4235 : : /*
4236 : : * Confirm adequate lock held during heap_update(), per rules from
4237 : : * README.tuplock section "Locking to write inplace-updated tables".
4238 : : */
4239 : : static void
399 noah@leadboat.com 4240 : 304307 : check_lock_if_inplace_updateable_rel(Relation relation,
4241 : : ItemPointer otid,
4242 : : HeapTuple newtup)
4243 : : {
4244 : : /* LOCKTAG_TUPLE acceptable for any catalog */
4245 [ + + ]: 304307 : switch (RelationGetRelid(relation))
4246 : : {
4247 : 66728 : case RelationRelationId:
4248 : : case DatabaseRelationId:
4249 : : {
4250 : : LOCKTAG tuptag;
4251 : :
4252 : 66728 : SET_LOCKTAG_TUPLE(tuptag,
4253 : : relation->rd_lockInfo.lockRelId.dbId,
4254 : : relation->rd_lockInfo.lockRelId.relId,
4255 : : ItemPointerGetBlockNumber(otid),
4256 : : ItemPointerGetOffsetNumber(otid));
4257 [ + + ]: 66728 : if (LockHeldByMe(&tuptag, InplaceUpdateTupleLock, false))
4258 : 30025 : return;
4259 : : }
4260 : 36703 : break;
4261 : 237579 : default:
4262 [ - + ]: 237579 : Assert(!IsInplaceUpdateRelation(relation));
4263 : 237579 : return;
4264 : : }
4265 : :
4266 [ + - - ]: 36703 : switch (RelationGetRelid(relation))
4267 : : {
4268 : 36703 : case RelationRelationId:
4269 : : {
4270 : : /* LOCKTAG_TUPLE or LOCKTAG_RELATION ok */
4271 : 36703 : Form_pg_class classForm = (Form_pg_class) GETSTRUCT(newtup);
4272 : 36703 : Oid relid = classForm->oid;
4273 : : Oid dbid;
4274 : : LOCKTAG tag;
4275 : :
4276 [ + + ]: 36703 : if (IsSharedRelation(relid))
4277 : 44 : dbid = InvalidOid;
4278 : : else
4279 : 36659 : dbid = MyDatabaseId;
4280 : :
4281 [ + + ]: 36703 : if (classForm->relkind == RELKIND_INDEX)
4282 : : {
4283 : 1007 : Relation irel = index_open(relid, AccessShareLock);
4284 : :
4285 : 1007 : SET_LOCKTAG_RELATION(tag, dbid, irel->rd_index->indrelid);
4286 : 1007 : index_close(irel, AccessShareLock);
4287 : : }
4288 : : else
4289 : 35696 : SET_LOCKTAG_RELATION(tag, dbid, relid);
4290 : :
4291 [ + + ]: 36703 : if (!LockHeldByMe(&tag, ShareUpdateExclusiveLock, false) &&
4292 [ - + ]: 33261 : !LockHeldByMe(&tag, ShareRowExclusiveLock, true))
399 noah@leadboat.com 4293 [ # # ]:UBC 0 : elog(WARNING,
4294 : : "missing lock for relation \"%s\" (OID %u, relkind %c) @ TID (%u,%u)",
4295 : : NameStr(classForm->relname),
4296 : : relid,
4297 : : classForm->relkind,
4298 : : ItemPointerGetBlockNumber(otid),
4299 : : ItemPointerGetOffsetNumber(otid));
4300 : : }
399 noah@leadboat.com 4301 :CBC 36703 : break;
399 noah@leadboat.com 4302 :UBC 0 : case DatabaseRelationId:
4303 : : {
4304 : : /* LOCKTAG_TUPLE required */
4305 : 0 : Form_pg_database dbForm = (Form_pg_database) GETSTRUCT(newtup);
4306 : :
4307 [ # # ]: 0 : elog(WARNING,
4308 : : "missing lock on database \"%s\" (OID %u) @ TID (%u,%u)",
4309 : : NameStr(dbForm->datname),
4310 : : dbForm->oid,
4311 : : ItemPointerGetBlockNumber(otid),
4312 : : ItemPointerGetOffsetNumber(otid));
4313 : : }
4314 : 0 : break;
4315 : : }
4316 : : }
4317 : :
4318 : : /*
4319 : : * Confirm adequate relation lock held, per rules from README.tuplock section
4320 : : * "Locking to write inplace-updated tables".
4321 : : */
4322 : : static void
399 noah@leadboat.com 4323 :CBC 90708 : check_inplace_rel_lock(HeapTuple oldtup)
4324 : : {
4325 : 90708 : Form_pg_class classForm = (Form_pg_class) GETSTRUCT(oldtup);
4326 : 90708 : Oid relid = classForm->oid;
4327 : : Oid dbid;
4328 : : LOCKTAG tag;
4329 : :
4330 [ + + ]: 90708 : if (IsSharedRelation(relid))
4331 : 8590 : dbid = InvalidOid;
4332 : : else
4333 : 82118 : dbid = MyDatabaseId;
4334 : :
4335 [ + + ]: 90708 : if (classForm->relkind == RELKIND_INDEX)
4336 : : {
4337 : 39517 : Relation irel = index_open(relid, AccessShareLock);
4338 : :
4339 : 39517 : SET_LOCKTAG_RELATION(tag, dbid, irel->rd_index->indrelid);
4340 : 39517 : index_close(irel, AccessShareLock);
4341 : : }
4342 : : else
4343 : 51191 : SET_LOCKTAG_RELATION(tag, dbid, relid);
4344 : :
4345 [ - + ]: 90708 : if (!LockHeldByMe(&tag, ShareUpdateExclusiveLock, true))
399 noah@leadboat.com 4346 [ # # ]:UBC 0 : elog(WARNING,
4347 : : "missing lock for relation \"%s\" (OID %u, relkind %c) @ TID (%u,%u)",
4348 : : NameStr(classForm->relname),
4349 : : relid,
4350 : : classForm->relkind,
4351 : : ItemPointerGetBlockNumber(&oldtup->t_self),
4352 : : ItemPointerGetOffsetNumber(&oldtup->t_self));
399 noah@leadboat.com 4353 :CBC 90708 : }
4354 : : #endif
4355 : :
4356 : : /*
4357 : : * Check if the specified attribute's values are the same. Subroutine for
4358 : : * HeapDetermineColumnsInfo.
4359 : : */
4360 : : static bool
1352 akapila@postgresql.o 4361 : 735370 : heap_attr_equals(TupleDesc tupdesc, int attrnum, Datum value1, Datum value2,
4362 : : bool isnull1, bool isnull2)
4363 : : {
4364 : : /*
4365 : : * If one value is NULL and other is not, then they are certainly not
4366 : : * equal
4367 : : */
6613 tgl@sss.pgh.pa.us 4368 [ + + ]: 735370 : if (isnull1 != isnull2)
4369 : 45 : return false;
4370 : :
4371 : : /*
4372 : : * If both are NULL, they can be considered equal.
4373 : : */
4374 [ + + ]: 735325 : if (isnull1)
4375 : 4991 : return true;
4376 : :
4377 : : /*
4378 : : * We do simple binary comparison of the two datums. This may be overly
4379 : : * strict because there can be multiple binary representations for the
4380 : : * same logical value. But we should be OK as long as there are no false
4381 : : * positives. Using a type-specific equality operator is messy because
4382 : : * there could be multiple notions of equality in different operator
4383 : : * classes; furthermore, we cannot safely invoke user-defined functions
4384 : : * while holding exclusive buffer lock.
4385 : : */
4386 [ - + ]: 730334 : if (attrnum <= 0)
4387 : : {
4388 : : /* The only allowed system columns are OIDs, so do this */
6613 tgl@sss.pgh.pa.us 4389 :UBC 0 : return (DatumGetObjectId(value1) == DatumGetObjectId(value2));
4390 : : }
4391 : : else
4392 : : {
4393 : : CompactAttribute *att;
4394 : :
6613 tgl@sss.pgh.pa.us 4395 [ - + ]:CBC 730334 : Assert(attrnum <= tupdesc->natts);
312 drowley@postgresql.o 4396 : 730334 : att = TupleDescCompactAttr(tupdesc, attrnum - 1);
6613 tgl@sss.pgh.pa.us 4397 : 730334 : return datumIsEqual(value1, value2, att->attbyval, att->attlen);
4398 : : }
4399 : : }
4400 : :
4401 : : /*
4402 : : * Check which columns are being updated.
4403 : : *
4404 : : * Given an updated tuple, determine (and return into the output bitmapset),
4405 : : * from those listed as interesting, the set of columns that changed.
4406 : : *
4407 : : * has_external indicates if any of the unmodified attributes (from those
4408 : : * listed as interesting) of the old tuple is a member of external_cols and is
4409 : : * stored externally.
4410 : : */
4411 : : static Bitmapset *
1352 akapila@postgresql.o 4412 : 304307 : HeapDetermineColumnsInfo(Relation relation,
4413 : : Bitmapset *interesting_cols,
4414 : : Bitmapset *external_cols,
4415 : : HeapTuple oldtup, HeapTuple newtup,
4416 : : bool *has_external)
4417 : : {
4418 : : int attidx;
3086 bruce@momjian.us 4419 : 304307 : Bitmapset *modified = NULL;
1352 akapila@postgresql.o 4420 : 304307 : TupleDesc tupdesc = RelationGetDescr(relation);
4421 : :
971 tgl@sss.pgh.pa.us 4422 : 304307 : attidx = -1;
4423 [ + + ]: 1039677 : while ((attidx = bms_next_member(interesting_cols, attidx)) >= 0)
4424 : : {
4425 : : /* attidx is zero-based, attrnum is the normal attribute number */
4426 : 735370 : AttrNumber attrnum = attidx + FirstLowInvalidHeapAttributeNumber;
4427 : : Datum value1,
4428 : : value2;
4429 : : bool isnull1,
4430 : : isnull2;
4431 : :
4432 : : /*
4433 : : * If it's a whole-tuple reference, say "not equal". It's not really
4434 : : * worth supporting this case, since it could only succeed after a
4435 : : * no-op update, which is hardly a case worth optimizing for.
4436 : : */
1352 akapila@postgresql.o 4437 [ - + ]: 735370 : if (attrnum == 0)
4438 : : {
971 tgl@sss.pgh.pa.us 4439 :UBC 0 : modified = bms_add_member(modified, attidx);
1352 akapila@postgresql.o 4440 :CBC 703203 : continue;
4441 : : }
4442 : :
4443 : : /*
4444 : : * Likewise, automatically say "not equal" for any system attribute
4445 : : * other than tableOID; we cannot expect these to be consistent in a
4446 : : * HOT chain, or even to be set correctly yet in the new tuple.
4447 : : */
4448 [ - + ]: 735370 : if (attrnum < 0)
4449 : : {
1352 akapila@postgresql.o 4450 [ # # ]:UBC 0 : if (attrnum != TableOidAttributeNumber)
4451 : : {
971 tgl@sss.pgh.pa.us 4452 : 0 : modified = bms_add_member(modified, attidx);
1352 akapila@postgresql.o 4453 : 0 : continue;
4454 : : }
4455 : : }
4456 : :
4457 : : /*
4458 : : * Extract the corresponding values. XXX this is pretty inefficient
4459 : : * if there are many indexed columns. Should we do a single
4460 : : * heap_deform_tuple call on each tuple, instead? But that doesn't
4461 : : * work for system columns ...
4462 : : */
1352 akapila@postgresql.o 4463 :CBC 735370 : value1 = heap_getattr(oldtup, attrnum, tupdesc, &isnull1);
4464 : 735370 : value2 = heap_getattr(newtup, attrnum, tupdesc, &isnull2);
4465 : :
4466 [ + + ]: 735370 : if (!heap_attr_equals(tupdesc, attrnum, value1,
4467 : : value2, isnull1, isnull2))
4468 : : {
971 tgl@sss.pgh.pa.us 4469 : 26789 : modified = bms_add_member(modified, attidx);
1352 akapila@postgresql.o 4470 : 26789 : continue;
4471 : : }
4472 : :
4473 : : /*
4474 : : * No need to check attributes that can't be stored externally. Note
4475 : : * that system attributes can't be stored externally.
4476 : : */
4477 [ + - + + ]: 708581 : if (attrnum < 0 || isnull1 ||
312 drowley@postgresql.o 4478 [ + + ]: 703590 : TupleDescCompactAttr(tupdesc, attrnum - 1)->attlen != -1)
1352 akapila@postgresql.o 4479 : 676414 : continue;
4480 : :
4481 : : /*
4482 : : * Check if the old tuple's attribute is stored externally and is a
4483 : : * member of external_cols.
4484 : : */
4485 [ + + + + ]: 32172 : if (VARATT_IS_EXTERNAL((struct varlena *) DatumGetPointer(value1)) &&
971 tgl@sss.pgh.pa.us 4486 : 5 : bms_is_member(attidx, external_cols))
1352 akapila@postgresql.o 4487 : 2 : *has_external = true;
4488 : : }
4489 : :
3135 alvherre@alvh.no-ip. 4490 : 304307 : return modified;
4491 : : }
4492 : :
4493 : : /*
4494 : : * simple_heap_update - replace a tuple
4495 : : *
4496 : : * This routine may be used to update a tuple when concurrent updates of
4497 : : * the target tuple are not expected (for example, because we have a lock
4498 : : * on the relation associated with the tuple). Any failure is reported
4499 : : * via ereport().
4500 : : */
4501 : : void
953 tomas.vondra@postgre 4502 : 110661 : simple_heap_update(Relation relation, ItemPointer otid, HeapTuple tup,
4503 : : TU_UpdateIndexes *update_indexes)
4504 : : {
4505 : : TM_Result result;
4506 : : TM_FailureData tmfd;
4507 : : LockTupleMode lockmode;
4508 : :
8079 tgl@sss.pgh.pa.us 4509 : 110661 : result = heap_update(relation, otid, tup,
4510 : : GetCurrentCommandId(true), InvalidSnapshot,
4511 : : true /* wait for commit */ ,
4512 : : &tmfd, &lockmode, update_indexes);
9044 4513 [ - + - - : 110661 : switch (result)
- ]
4514 : : {
2411 andres@anarazel.de 4515 :UBC 0 : case TM_SelfModified:
4516 : : /* Tuple was already updated in current command? */
8135 tgl@sss.pgh.pa.us 4517 [ # # ]: 0 : elog(ERROR, "tuple already updated by self");
4518 : : break;
4519 : :
2411 andres@anarazel.de 4520 :CBC 110661 : case TM_Ok:
4521 : : /* done successfully */
9044 tgl@sss.pgh.pa.us 4522 : 110661 : break;
4523 : :
2411 andres@anarazel.de 4524 :UBC 0 : case TM_Updated:
8135 tgl@sss.pgh.pa.us 4525 [ # # ]: 0 : elog(ERROR, "tuple concurrently updated");
4526 : : break;
4527 : :
2411 andres@anarazel.de 4528 : 0 : case TM_Deleted:
4529 [ # # ]: 0 : elog(ERROR, "tuple concurrently deleted");
4530 : : break;
4531 : :
9044 tgl@sss.pgh.pa.us 4532 : 0 : default:
8135 4533 [ # # ]: 0 : elog(ERROR, "unrecognized heap_update status: %u", result);
4534 : : break;
4535 : : }
9044 tgl@sss.pgh.pa.us 4536 :CBC 110661 : }
4537 : :
4538 : :
4539 : : /*
4540 : : * Return the MultiXactStatus corresponding to the given tuple lock mode.
4541 : : */
4542 : : static MultiXactStatus
4661 alvherre@alvh.no-ip. 4543 : 1224 : get_mxact_status_for_lock(LockTupleMode mode, bool is_update)
4544 : : {
4545 : : int retval;
4546 : :
4547 [ + + ]: 1224 : if (is_update)
4548 : 96 : retval = tupleLockExtraInfo[mode].updstatus;
4549 : : else
4550 : 1128 : retval = tupleLockExtraInfo[mode].lockstatus;
4551 : :
4552 [ - + ]: 1224 : if (retval == -1)
4661 alvherre@alvh.no-ip. 4553 [ # # # # ]:UBC 0 : elog(ERROR, "invalid lock tuple mode %d/%s", mode,
4554 : : is_update ? "true" : "false");
4555 : :
4508 alvherre@alvh.no-ip. 4556 :CBC 1224 : return (MultiXactStatus) retval;
4557 : : }
4558 : :
4559 : : /*
4560 : : * heap_lock_tuple - lock a tuple in shared or exclusive mode
4561 : : *
4562 : : * Note that this acquires a buffer pin, which the caller must release.
4563 : : *
4564 : : * Input parameters:
4565 : : * relation: relation containing tuple (caller must hold suitable lock)
4566 : : * cid: current command ID (used for visibility test, and stored into
4567 : : * tuple's cmax if lock is successful)
4568 : : * mode: indicates if shared or exclusive tuple lock is desired
4569 : : * wait_policy: what to do if tuple lock is not available
4570 : : * follow_updates: if true, follow the update chain to also lock descendant
4571 : : * tuples.
4572 : : *
4573 : : * Output parameters:
4574 : : * *tuple: all fields filled in
4575 : : * *buffer: set to buffer holding tuple (pinned but not locked at exit)
4576 : : * *tmfd: filled in failure cases (see below)
4577 : : *
4578 : : * Function results are the same as the ones for table_tuple_lock().
4579 : : *
4580 : : * In the failure cases other than TM_Invisible, the routine fills
4581 : : * *tmfd with the tuple's t_ctid, t_xmax (resolving a possible MultiXact,
4582 : : * if necessary), and t_cmax (the last only for TM_SelfModified,
4583 : : * since we cannot obtain cmax from a combo CID generated by another
4584 : : * transaction).
4585 : : * See comments for struct TM_FailureData for additional info.
4586 : : *
4587 : : * See README.tuplock for a thorough explanation of this mechanism.
4588 : : */
4589 : : TM_Result
565 akorotkov@postgresql 4590 : 85042 : heap_lock_tuple(Relation relation, HeapTuple tuple,
4591 : : CommandId cid, LockTupleMode mode, LockWaitPolicy wait_policy,
4592 : : bool follow_updates,
4593 : : Buffer *buffer, TM_FailureData *tmfd)
4594 : : {
4595 : : TM_Result result;
4596 : 85042 : ItemPointer tid = &(tuple->t_self);
4597 : : ItemId lp;
4598 : : Page page;
3389 andres@anarazel.de 4599 : 85042 : Buffer vmbuffer = InvalidBuffer;
4600 : : BlockNumber block;
4601 : : TransactionId xid,
4602 : : xmax;
4603 : : uint16 old_infomask,
4604 : : new_infomask,
4605 : : new_infomask2;
3854 alvherre@alvh.no-ip. 4606 : 85042 : bool first_time = true;
2324 4607 : 85042 : bool skip_tuple_lock = false;
7486 tgl@sss.pgh.pa.us 4608 : 85042 : bool have_tuple_lock = false;
3389 andres@anarazel.de 4609 : 85042 : bool cleared_all_frozen = false;
4610 : :
565 akorotkov@postgresql 4611 : 85042 : *buffer = ReadBuffer(relation, ItemPointerGetBlockNumber(tid));
3389 andres@anarazel.de 4612 : 85042 : block = ItemPointerGetBlockNumber(tid);
4613 : :
4614 : : /*
4615 : : * Before locking the buffer, pin the visibility map page if it appears to
4616 : : * be necessary. Since we haven't got the lock yet, someone else might be
4617 : : * in the middle of changing this, so we'll need to recheck after we have
4618 : : * the lock.
4619 : : */
565 akorotkov@postgresql 4620 [ + + ]: 85042 : if (PageIsAllVisible(BufferGetPage(*buffer)))
3389 andres@anarazel.de 4621 : 1666 : visibilitymap_pin(relation, block, &vmbuffer);
4622 : :
565 akorotkov@postgresql 4623 : 85042 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
4624 : :
4625 : 85042 : page = BufferGetPage(*buffer);
6316 tgl@sss.pgh.pa.us 4626 : 85042 : lp = PageGetItemId(page, ItemPointerGetOffsetNumber(tid));
6621 4627 [ - + ]: 85042 : Assert(ItemIdIsNormal(lp));
4628 : :
6316 4629 : 85042 : tuple->t_data = (HeapTupleHeader) PageGetItem(page, lp);
9814 vadim4o@yahoo.com 4630 : 85042 : tuple->t_len = ItemIdGetLength(lp);
7374 tgl@sss.pgh.pa.us 4631 : 85042 : tuple->t_tableOid = RelationGetRelid(relation);
4632 : :
9814 vadim4o@yahoo.com 4633 : 11 : l3:
565 akorotkov@postgresql 4634 : 85053 : result = HeapTupleSatisfiesUpdate(tuple, cid, *buffer);
4635 : :
2411 andres@anarazel.de 4636 [ + + ]: 85053 : if (result == TM_Invisible)
4637 : : {
4638 : : /*
4639 : : * This is possible, but only when locking a tuple for ON CONFLICT
4640 : : * UPDATE. We return this value here rather than throwing an error in
4641 : : * order to give that case the opportunity to throw a more specific
4642 : : * error.
4643 : : */
4644 : 12 : result = TM_Invisible;
3389 4645 : 12 : goto out_locked;
4646 : : }
2411 4647 [ + + + + ]: 85041 : else if (result == TM_BeingModified ||
4648 [ - + ]: 77114 : result == TM_Updated ||
4649 : : result == TM_Deleted)
4650 : : {
4651 : : TransactionId xwait;
4652 : : uint16 infomask;
4653 : : uint16 infomask2;
4654 : : bool require_sleep;
4655 : : ItemPointerData t_ctid;
4656 : :
4657 : : /* must copy state data before unlocking buffer */
4661 alvherre@alvh.no-ip. 4658 : 7927 : xwait = HeapTupleHeaderGetRawXmax(tuple->t_data);
7486 tgl@sss.pgh.pa.us 4659 : 7927 : infomask = tuple->t_data->t_infomask;
4661 alvherre@alvh.no-ip. 4660 : 7927 : infomask2 = tuple->t_data->t_infomask2;
4661 : 7927 : ItemPointerCopy(&tuple->t_data->t_ctid, &t_ctid);
4662 : :
565 akorotkov@postgresql 4663 : 7927 : LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
4664 : :
4665 : : /*
4666 : : * If any subtransaction of the current top transaction already holds
4667 : : * a lock as strong as or stronger than what we're requesting, we
4668 : : * effectively hold the desired lock already. We *must* succeed
4669 : : * without trying to take the tuple lock, else we will deadlock
4670 : : * against anyone wanting to acquire a stronger lock.
4671 : : *
4672 : : * Note we only do this the first time we loop on the HTSU result;
4673 : : * there is no point in testing in subsequent passes, because
4674 : : * evidently our own transaction cannot have acquired a new lock after
4675 : : * the first time we checked.
4676 : : */
3854 alvherre@alvh.no-ip. 4677 [ + + ]: 7927 : if (first_time)
4678 : : {
4679 : 7919 : first_time = false;
4680 : :
4681 [ + + ]: 7919 : if (infomask & HEAP_XMAX_IS_MULTI)
4682 : : {
4683 : : int i;
4684 : : int nmembers;
4685 : : MultiXactMember *members;
4686 : :
4687 : : /*
4688 : : * We don't need to allow old multixacts here; if that had
4689 : : * been the case, HeapTupleSatisfiesUpdate would have returned
4690 : : * MayBeUpdated and we wouldn't be here.
4691 : : */
4692 : : nmembers =
4693 : 98 : GetMultiXactIdMembers(xwait, &members, false,
4694 : 98 : HEAP_XMAX_IS_LOCKED_ONLY(infomask));
4695 : :
4696 [ + + ]: 301 : for (i = 0; i < nmembers; i++)
4697 : : {
4698 : : /* only consider members of our own transaction */
4699 [ + + ]: 217 : if (!TransactionIdIsCurrentTransactionId(members[i].xid))
4700 : 168 : continue;
4701 : :
4702 [ + + ]: 49 : if (TUPLOCK_from_mxstatus(members[i].status) >= mode)
4703 : : {
4661 4704 : 14 : pfree(members);
2411 andres@anarazel.de 4705 : 14 : result = TM_Ok;
3389 4706 : 14 : goto out_unlocked;
4707 : : }
4708 : : else
4709 : : {
4710 : : /*
4711 : : * Disable acquisition of the heavyweight tuple lock.
4712 : : * Otherwise, when promoting a weaker lock, we might
4713 : : * deadlock with another locker that has acquired the
4714 : : * heavyweight tuple lock and is waiting for our
4715 : : * transaction to finish.
4716 : : *
4717 : : * Note that in this case we still need to wait for
4718 : : * the multixact if required, to avoid acquiring
4719 : : * conflicting locks.
4720 : : */
2324 alvherre@alvh.no-ip. 4721 : 35 : skip_tuple_lock = true;
4722 : : }
4723 : : }
4724 : :
3854 4725 [ + - ]: 84 : if (members)
4726 : 84 : pfree(members);
4727 : : }
4728 [ + + ]: 7821 : else if (TransactionIdIsCurrentTransactionId(xwait))
4729 : : {
4730 [ + + + + : 6562 : switch (mode)
- ]
4731 : : {
4732 : 166 : case LockTupleKeyShare:
4733 [ - + - - : 166 : Assert(HEAP_XMAX_IS_KEYSHR_LOCKED(infomask) ||
- - ]
4734 : : HEAP_XMAX_IS_SHR_LOCKED(infomask) ||
4735 : : HEAP_XMAX_IS_EXCL_LOCKED(infomask));
2411 andres@anarazel.de 4736 : 166 : result = TM_Ok;
3389 4737 : 166 : goto out_unlocked;
3854 alvherre@alvh.no-ip. 4738 : 23 : case LockTupleShare:
4739 [ + + - + ]: 29 : if (HEAP_XMAX_IS_SHR_LOCKED(infomask) ||
4740 : 6 : HEAP_XMAX_IS_EXCL_LOCKED(infomask))
4741 : : {
2411 andres@anarazel.de 4742 : 17 : result = TM_Ok;
3389 4743 : 17 : goto out_unlocked;
4744 : : }
3854 alvherre@alvh.no-ip. 4745 : 6 : break;
4746 : 71 : case LockTupleNoKeyExclusive:
4747 [ + + ]: 71 : if (HEAP_XMAX_IS_EXCL_LOCKED(infomask))
4748 : : {
2411 andres@anarazel.de 4749 : 59 : result = TM_Ok;
3389 4750 : 59 : goto out_unlocked;
4751 : : }
3854 alvherre@alvh.no-ip. 4752 : 12 : break;
4753 : 6302 : case LockTupleExclusive:
4754 [ + + ]: 6302 : if (HEAP_XMAX_IS_EXCL_LOCKED(infomask) &&
4755 [ + + ]: 1262 : infomask2 & HEAP_KEYS_UPDATED)
4756 : : {
2411 andres@anarazel.de 4757 : 1241 : result = TM_Ok;
3389 4758 : 1241 : goto out_unlocked;
4759 : : }
3854 alvherre@alvh.no-ip. 4760 : 5061 : break;
4761 : : }
4762 : : }
4763 : : }
4764 : :
4765 : : /*
4766 : : * Initially assume that we will have to wait for the locking
4767 : : * transaction(s) to finish. We check various cases below in which
4768 : : * this can be turned off.
4769 : : */
4661 4770 : 6430 : require_sleep = true;
4771 [ + + ]: 6430 : if (mode == LockTupleKeyShare)
4772 : : {
4773 : : /*
4774 : : * If we're requesting KeyShare, and there's no update present, we
4775 : : * don't need to wait. Even if there is an update, we can still
4776 : : * continue if the key hasn't been modified.
4777 : : *
4778 : : * However, if there are updates, we need to walk the update chain
4779 : : * to mark future versions of the row as locked, too. That way,
4780 : : * if somebody deletes that future version, we're protected
4781 : : * against the key going away. This locking of future versions
4782 : : * could block momentarily, if a concurrent transaction is
4783 : : * deleting a key; or it could return a value to the effect that
4784 : : * the transaction deleting the key has already committed. So we
4785 : : * do this before re-locking the buffer; otherwise this would be
4786 : : * prone to deadlocks.
4787 : : *
4788 : : * Note that the TID we're locking was grabbed before we unlocked
4789 : : * the buffer. For it to change while we're not looking, the
4790 : : * other properties we're testing for below after re-locking the
4791 : : * buffer would also change, in which case we would restart this
4792 : : * loop above.
4793 : : */
4794 [ + + ]: 614 : if (!(infomask2 & HEAP_KEYS_UPDATED))
4795 : : {
4796 : : bool updated;
4797 : :
4798 : 571 : updated = !HEAP_XMAX_IS_LOCKED_ONLY(infomask);
4799 : :
4800 : : /*
4801 : : * If there are updates, follow the update chain; bail out if
4802 : : * that cannot be done.
4803 : : */
4804 [ + - + + ]: 571 : if (follow_updates && updated)
4805 : : {
4806 : : TM_Result res;
4807 : :
4808 : 50 : res = heap_lock_updated_tuple(relation, tuple, &t_ctid,
4809 : : GetCurrentTransactionId(),
4810 : : mode);
2411 andres@anarazel.de 4811 [ + + ]: 50 : if (res != TM_Ok)
4812 : : {
4661 alvherre@alvh.no-ip. 4813 : 6 : result = res;
4814 : : /* recovery code expects to have buffer lock held */
565 akorotkov@postgresql 4815 : 6 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
4661 alvherre@alvh.no-ip. 4816 : 190 : goto failed;
4817 : : }
4818 : : }
4819 : :
565 akorotkov@postgresql 4820 : 565 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
4821 : :
4822 : : /*
4823 : : * Make sure it's still an appropriate lock, else start over.
4824 : : * Also, if it wasn't updated before we released the lock, but
4825 : : * is updated now, we start over too; the reason is that we
4826 : : * now need to follow the update chain to lock the new
4827 : : * versions.
4828 : : */
4661 alvherre@alvh.no-ip. 4829 [ + + ]: 565 : if (!HeapTupleHeaderIsOnlyLocked(tuple->t_data) &&
4830 [ + - ]: 43 : ((tuple->t_data->t_infomask2 & HEAP_KEYS_UPDATED) ||
4831 [ - + ]: 43 : !updated))
4832 : 11 : goto l3;
4833 : :
4834 : : /* Things look okay, so we can skip sleeping */
4835 : 565 : require_sleep = false;
4836 : :
4837 : : /*
4838 : : * Note we allow Xmax to change here; other updaters/lockers
4839 : : * could have modified it before we grabbed the buffer lock.
4840 : : * However, this is not a problem, because with the recheck we
4841 : : * just did we ensure that they still don't conflict with the
4842 : : * lock we want.
4843 : : */
4844 : : }
4845 : : }
4846 [ + + ]: 5816 : else if (mode == LockTupleShare)
4847 : : {
4848 : : /*
4849 : : * If we're requesting Share, we can similarly avoid sleeping if
4850 : : * there's no update and no exclusive lock present.
4851 : : */
4852 [ + - ]: 443 : if (HEAP_XMAX_IS_LOCKED_ONLY(infomask) &&
4853 [ + + ]: 443 : !HEAP_XMAX_IS_EXCL_LOCKED(infomask))
4854 : : {
565 akorotkov@postgresql 4855 : 437 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
4856 : :
4857 : : /*
4858 : : * Make sure it's still an appropriate lock, else start over.
4859 : : * See above about allowing xmax to change.
4860 : : */
4661 alvherre@alvh.no-ip. 4861 [ + - - + ]: 874 : if (!HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_data->t_infomask) ||
4862 : 437 : HEAP_XMAX_IS_EXCL_LOCKED(tuple->t_data->t_infomask))
4661 alvherre@alvh.no-ip. 4863 :UBC 0 : goto l3;
4661 alvherre@alvh.no-ip. 4864 :CBC 437 : require_sleep = false;
4865 : : }
4866 : : }
4867 [ + + ]: 5373 : else if (mode == LockTupleNoKeyExclusive)
4868 : : {
4869 : : /*
4870 : : * If we're requesting NoKeyExclusive, we might also be able to
4871 : : * avoid sleeping; just ensure that there no conflicting lock
4872 : : * already acquired.
4873 : : */
4874 [ + + ]: 163 : if (infomask & HEAP_XMAX_IS_MULTI)
4875 : : {
3959 4876 [ + + ]: 26 : if (!DoesMultiXactIdConflict((MultiXactId) xwait, infomask,
4877 : : mode, NULL))
4878 : : {
4879 : : /*
4880 : : * No conflict, but if the xmax changed under us in the
4881 : : * meantime, start over.
4882 : : */
565 akorotkov@postgresql 4883 : 13 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
3959 alvherre@alvh.no-ip. 4884 [ + - - + ]: 26 : if (xmax_infomask_changed(tuple->t_data->t_infomask, infomask) ||
4885 : 13 : !TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple->t_data),
4886 : : xwait))
3959 alvherre@alvh.no-ip. 4887 :UBC 0 : goto l3;
4888 : :
4889 : : /* otherwise, we're good */
3959 alvherre@alvh.no-ip. 4890 :CBC 13 : require_sleep = false;
4891 : : }
4892 : : }
4661 4893 [ + + ]: 137 : else if (HEAP_XMAX_IS_KEYSHR_LOCKED(infomask))
4894 : : {
565 akorotkov@postgresql 4895 : 18 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
4896 : :
4897 : : /* if the xmax changed in the meantime, start over */
4205 alvherre@alvh.no-ip. 4898 [ + - - + ]: 36 : if (xmax_infomask_changed(tuple->t_data->t_infomask, infomask) ||
2098 4899 : 18 : !TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple->t_data),
4900 : : xwait))
4661 alvherre@alvh.no-ip. 4901 :UBC 0 : goto l3;
4902 : : /* otherwise, we're good */
4661 alvherre@alvh.no-ip. 4903 :CBC 18 : require_sleep = false;
4904 : : }
4905 : : }
4906 : :
4907 : : /*
4908 : : * As a check independent from those above, we can also avoid sleeping
4909 : : * if the current transaction is the sole locker of the tuple. Note
4910 : : * that the strength of the lock already held is irrelevant; this is
4911 : : * not about recording the lock in Xmax (which will be done regardless
4912 : : * of this optimization, below). Also, note that the cases where we
4913 : : * hold a lock stronger than we are requesting are already handled
4914 : : * above by not doing anything.
4915 : : *
4916 : : * Note we only deal with the non-multixact case here; MultiXactIdWait
4917 : : * is well equipped to deal with this situation on its own.
4918 : : */
3854 4919 [ + + + + : 11775 : if (require_sleep && !(infomask & HEAP_XMAX_IS_MULTI) &&
+ + ]
4920 : 5351 : TransactionIdIsCurrentTransactionId(xwait))
4921 : : {
4922 : : /* ... but if the xmax changed in the meantime, start over */
565 akorotkov@postgresql 4923 : 5061 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
3854 alvherre@alvh.no-ip. 4924 [ + - - + ]: 10122 : if (xmax_infomask_changed(tuple->t_data->t_infomask, infomask) ||
4925 : 5061 : !TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple->t_data),
4926 : : xwait))
3854 alvherre@alvh.no-ip. 4927 :UBC 0 : goto l3;
3854 alvherre@alvh.no-ip. 4928 [ - + ]:CBC 5061 : Assert(HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_data->t_infomask));
4929 : 5061 : require_sleep = false;
4930 : : }
4931 : :
4932 : : /*
4933 : : * Time to sleep on the other transaction/multixact, if necessary.
4934 : : *
4935 : : * If the other transaction is an update/delete that's already
4936 : : * committed, then sleeping cannot possibly do any good: if we're
4937 : : * required to sleep, get out to raise an error instead.
4938 : : *
4939 : : * By here, we either have already acquired the buffer exclusive lock,
4940 : : * or we must wait for the locking transaction or multixact; so below
4941 : : * we ensure that we grab buffer lock after the sleep.
4942 : : */
2411 andres@anarazel.de 4943 [ + + + + : 6424 : if (require_sleep && (result == TM_Updated || result == TM_Deleted))
- + ]
4944 : : {
565 akorotkov@postgresql 4945 : 146 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
3392 alvherre@alvh.no-ip. 4946 : 146 : goto failed;
4947 : : }
4948 [ + + ]: 6278 : else if (require_sleep)
4949 : : {
4950 : : /*
4951 : : * Acquire tuple lock to establish our priority for the tuple, or
4952 : : * die trying. LockTuple will release us when we are next-in-line
4953 : : * for the tuple. We must do this even if we are share-locking,
4954 : : * but not if we already have a weaker lock on the tuple.
4955 : : *
4956 : : * If we are forced to "start over" below, we keep the tuple lock;
4957 : : * this arranges that we stay at the head of the line while
4958 : : * rechecking tuple state.
4959 : : */
2324 4960 [ + + ]: 184 : if (!skip_tuple_lock &&
4961 [ + + ]: 168 : !heap_acquire_tuplock(relation, tid, mode, wait_policy,
4962 : : &have_tuple_lock))
4963 : : {
4964 : : /*
4965 : : * This can only happen if wait_policy is Skip and the lock
4966 : : * couldn't be obtained.
4967 : : */
2411 andres@anarazel.de 4968 : 1 : result = TM_WouldBlock;
4969 : : /* recovery code expects to have buffer lock held */
565 akorotkov@postgresql 4970 : 1 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
3959 alvherre@alvh.no-ip. 4971 : 1 : goto failed;
4972 : : }
4973 : :
4661 4974 [ + + ]: 182 : if (infomask & HEAP_XMAX_IS_MULTI)
4975 : : {
4976 : 40 : MultiXactStatus status = get_mxact_status_for_lock(mode, false);
4977 : :
4978 : : /* We only ever lock tuples, never update them */
4979 [ - + ]: 40 : if (status >= MultiXactStatusNoKeyUpdate)
4661 alvherre@alvh.no-ip. 4980 [ # # ]:UBC 0 : elog(ERROR, "invalid lock mode in heap_lock_tuple");
4981 : :
4982 : : /* wait for multixact to end, or die trying */
4039 alvherre@alvh.no-ip. 4983 [ + + + - ]:CBC 40 : switch (wait_policy)
4984 : : {
4985 : 36 : case LockWaitBlock:
4986 : 36 : MultiXactIdWait((MultiXactId) xwait, status, infomask,
4987 : : relation, &tuple->t_self, XLTW_Lock, NULL);
4988 : 36 : break;
4989 : 2 : case LockWaitSkip:
4990 [ + - ]: 2 : if (!ConditionalMultiXactIdWait((MultiXactId) xwait,
4991 : : status, infomask, relation,
4992 : : NULL, false))
4993 : : {
2411 andres@anarazel.de 4994 : 2 : result = TM_WouldBlock;
4995 : : /* recovery code expects to have buffer lock held */
565 akorotkov@postgresql 4996 : 2 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
4039 alvherre@alvh.no-ip. 4997 : 2 : goto failed;
4998 : : }
4039 alvherre@alvh.no-ip. 4999 :UBC 0 : break;
4039 alvherre@alvh.no-ip. 5000 :CBC 2 : case LockWaitError:
5001 [ + - ]: 2 : if (!ConditionalMultiXactIdWait((MultiXactId) xwait,
5002 : : status, infomask, relation,
5003 : : NULL, log_lock_failures))
5004 [ + - ]: 2 : ereport(ERROR,
5005 : : (errcode(ERRCODE_LOCK_NOT_AVAILABLE),
5006 : : errmsg("could not obtain lock on row in relation \"%s\"",
5007 : : RelationGetRelationName(relation))));
5008 : :
4039 alvherre@alvh.no-ip. 5009 :UBC 0 : break;
5010 : : }
5011 : :
5012 : : /*
5013 : : * Of course, the multixact might not be done here: if we're
5014 : : * requesting a light lock mode, other transactions with light
5015 : : * locks could still be alive, as well as locks owned by our
5016 : : * own xact or other subxacts of this backend. We need to
5017 : : * preserve the surviving MultiXact members. Note that it
5018 : : * isn't absolutely necessary in the latter case, but doing so
5019 : : * is simpler.
5020 : : */
5021 : : }
5022 : : else
5023 : : {
5024 : : /* wait for regular transaction to end, or die trying */
4039 alvherre@alvh.no-ip. 5025 [ + + + - ]:CBC 142 : switch (wait_policy)
5026 : : {
5027 : 103 : case LockWaitBlock:
3919 heikki.linnakangas@i 5028 : 103 : XactLockTableWait(xwait, relation, &tuple->t_self,
5029 : : XLTW_Lock);
4039 alvherre@alvh.no-ip. 5030 : 103 : break;
5031 : 33 : case LockWaitSkip:
228 fujii@postgresql.org 5032 [ + - ]: 33 : if (!ConditionalXactLockTableWait(xwait, false))
5033 : : {
2411 andres@anarazel.de 5034 : 33 : result = TM_WouldBlock;
5035 : : /* recovery code expects to have buffer lock held */
565 akorotkov@postgresql 5036 : 33 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
4039 alvherre@alvh.no-ip. 5037 : 33 : goto failed;
5038 : : }
4039 alvherre@alvh.no-ip. 5039 :UBC 0 : break;
4039 alvherre@alvh.no-ip. 5040 :CBC 6 : case LockWaitError:
147 fujii@postgresql.org 5041 [ + - ]: 6 : if (!ConditionalXactLockTableWait(xwait, log_lock_failures))
4039 alvherre@alvh.no-ip. 5042 [ + - ]: 6 : ereport(ERROR,
5043 : : (errcode(ERRCODE_LOCK_NOT_AVAILABLE),
5044 : : errmsg("could not obtain lock on row in relation \"%s\"",
5045 : : RelationGetRelationName(relation))));
4039 alvherre@alvh.no-ip. 5046 :UBC 0 : break;
5047 : : }
5048 : : }
5049 : :
5050 : : /* if there are updates, follow the update chain */
3854 alvherre@alvh.no-ip. 5051 [ + + + + ]:CBC 139 : if (follow_updates && !HEAP_XMAX_IS_LOCKED_ONLY(infomask))
5052 : : {
5053 : : TM_Result res;
5054 : :
5055 : 55 : res = heap_lock_updated_tuple(relation, tuple, &t_ctid,
5056 : : GetCurrentTransactionId(),
5057 : : mode);
2411 andres@anarazel.de 5058 [ + + ]: 55 : if (res != TM_Ok)
5059 : : {
3854 alvherre@alvh.no-ip. 5060 : 2 : result = res;
5061 : : /* recovery code expects to have buffer lock held */
565 akorotkov@postgresql 5062 : 2 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
3854 alvherre@alvh.no-ip. 5063 : 2 : goto failed;
5064 : : }
5065 : : }
5066 : :
565 akorotkov@postgresql 5067 : 137 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
5068 : :
5069 : : /*
5070 : : * xwait is done, but if xwait had just locked the tuple then some
5071 : : * other xact could update this tuple before we get to this point.
5072 : : * Check for xmax change, and start over if so.
5073 : : */
3854 alvherre@alvh.no-ip. 5074 [ + + + + ]: 265 : if (xmax_infomask_changed(tuple->t_data->t_infomask, infomask) ||
5075 : 128 : !TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple->t_data),
5076 : : xwait))
5077 : 11 : goto l3;
5078 : :
5079 [ + + ]: 126 : if (!(infomask & HEAP_XMAX_IS_MULTI))
5080 : : {
5081 : : /*
5082 : : * Otherwise check if it committed or aborted. Note we cannot
5083 : : * be here if the tuple was only locked by somebody who didn't
5084 : : * conflict with us; that would have been handled above. So
5085 : : * that transaction must necessarily be gone by now. But
5086 : : * don't check for this in the multixact case, because some
5087 : : * locker transactions might still be running.
5088 : : */
565 akorotkov@postgresql 5089 : 92 : UpdateXmaxHintBits(tuple->t_data, *buffer, xwait);
5090 : : }
5091 : : }
5092 : :
5093 : : /* By here, we're certain that we hold buffer exclusive lock again */
5094 : :
5095 : : /*
5096 : : * We may lock if previous xmax aborted, or if it committed but only
5097 : : * locked the tuple without updating it; or if we didn't have to wait
5098 : : * at all for whatever reason.
5099 : : */
4661 alvherre@alvh.no-ip. 5100 [ + + ]: 6220 : if (!require_sleep ||
5101 [ + + + + ]: 222 : (tuple->t_data->t_infomask & HEAP_XMAX_INVALID) ||
5102 [ + + ]: 176 : HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_data->t_infomask) ||
5103 : 80 : HeapTupleHeaderIsOnlyLocked(tuple->t_data))
2411 andres@anarazel.de 5104 : 6147 : result = TM_Ok;
1709 alvherre@alvh.no-ip. 5105 [ + + ]: 73 : else if (!ItemPointerEquals(&tuple->t_self, &tuple->t_data->t_ctid))
2411 andres@anarazel.de 5106 : 54 : result = TM_Updated;
5107 : : else
5108 : 19 : result = TM_Deleted;
5109 : : }
5110 : :
4661 alvherre@alvh.no-ip. 5111 : 77114 : failed:
2411 andres@anarazel.de 5112 [ + + ]: 83524 : if (result != TM_Ok)
5113 : : {
5114 [ + + + + : 269 : Assert(result == TM_SelfModified || result == TM_Updated ||
+ + - + ]
5115 : : result == TM_Deleted || result == TM_WouldBlock);
5116 : :
5117 : : /*
5118 : : * When locking a tuple under LockWaitSkip semantics and we fail with
5119 : : * TM_WouldBlock above, it's possible for concurrent transactions to
5120 : : * release the lock and set HEAP_XMAX_INVALID in the meantime. So
5121 : : * this assert is slightly different from the equivalent one in
5122 : : * heap_delete and heap_update.
5123 : : */
1393 alvherre@alvh.no-ip. 5124 [ + + - + ]: 269 : Assert((result == TM_WouldBlock) ||
5125 : : !(tuple->t_data->t_infomask & HEAP_XMAX_INVALID));
2411 andres@anarazel.de 5126 [ + + - + ]: 269 : Assert(result != TM_Updated ||
5127 : : !ItemPointerEquals(&tuple->t_self, &tuple->t_data->t_ctid));
5128 : 269 : tmfd->ctid = tuple->t_data->t_ctid;
5129 : 269 : tmfd->xmax = HeapTupleHeaderGetUpdateXid(tuple->t_data);
5130 [ + + ]: 269 : if (result == TM_SelfModified)
5131 : 6 : tmfd->cmax = HeapTupleHeaderGetCmax(tuple->t_data);
5132 : : else
5133 : 263 : tmfd->cmax = InvalidCommandId;
3389 5134 : 269 : goto out_locked;
5135 : : }
5136 : :
5137 : : /*
5138 : : * If we didn't pin the visibility map page and the page has become all
5139 : : * visible while we were busy locking the buffer, or during some
5140 : : * subsequent window during which we had it unlocked, we'll have to unlock
5141 : : * and re-lock, to avoid holding the buffer lock across I/O. That's a bit
5142 : : * unfortunate, especially since we'll now have to recheck whether the
5143 : : * tuple has been locked or updated under us, but hopefully it won't
5144 : : * happen very often.
5145 : : */
3372 5146 [ + + - + ]: 83255 : if (vmbuffer == InvalidBuffer && PageIsAllVisible(page))
5147 : : {
565 akorotkov@postgresql 5148 :UBC 0 : LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
3372 andres@anarazel.de 5149 : 0 : visibilitymap_pin(relation, block, &vmbuffer);
565 akorotkov@postgresql 5150 : 0 : LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
3372 andres@anarazel.de 5151 : 0 : goto l3;
5152 : : }
5153 : :
4661 alvherre@alvh.no-ip. 5154 :CBC 83255 : xmax = HeapTupleHeaderGetRawXmax(tuple->t_data);
5155 : 83255 : old_infomask = tuple->t_data->t_infomask;
5156 : :
5157 : : /*
5158 : : * If this is the first possibly-multixact-able operation in the current
5159 : : * transaction, set my per-backend OldestMemberMXactId setting. We can be
5160 : : * certain that the transaction will never become a member of any older
5161 : : * MultiXactIds than that. (We have to do this even if we end up just
5162 : : * using our own TransactionId below, since some other backend could
5163 : : * incorporate our XID into a MultiXact immediately afterwards.)
5164 : : */
5165 : 83255 : MultiXactIdSetOldestMember();
5166 : :
5167 : : /*
5168 : : * Compute the new xmax and infomask to store into the tuple. Note we do
5169 : : * not modify the tuple just yet, because that would leave it in the wrong
5170 : : * state if multixact.c elogs.
5171 : : */
5172 : 83255 : compute_new_xmax_infomask(xmax, old_infomask, tuple->t_data->t_infomask2,
5173 : : GetCurrentTransactionId(), mode, false,
5174 : : &xid, &new_infomask, &new_infomask2);
5175 : :
7488 tgl@sss.pgh.pa.us 5176 : 83255 : START_CRIT_SECTION();
5177 : :
5178 : : /*
5179 : : * Store transaction information of xact locking the tuple.
5180 : : *
5181 : : * Note: Cmax is meaningless in this context, so don't set it; this avoids
5182 : : * possibly generating a useless combo CID. Moreover, if we're locking a
5183 : : * previously updated tuple, it's important to preserve the Cmax.
5184 : : *
5185 : : * Also reset the HOT UPDATE bit, but only if there's no update; otherwise
5186 : : * we would break the HOT chain.
5187 : : */
4661 alvherre@alvh.no-ip. 5188 : 83255 : tuple->t_data->t_infomask &= ~HEAP_XMAX_BITS;
5189 : 83255 : tuple->t_data->t_infomask2 &= ~HEAP_KEYS_UPDATED;
5190 : 83255 : tuple->t_data->t_infomask |= new_infomask;
5191 : 83255 : tuple->t_data->t_infomask2 |= new_infomask2;
5192 [ + + ]: 83255 : if (HEAP_XMAX_IS_LOCKED_ONLY(new_infomask))
5193 : 83216 : HeapTupleHeaderClearHotUpdated(tuple->t_data);
7712 tgl@sss.pgh.pa.us 5194 : 83255 : HeapTupleHeaderSetXmax(tuple->t_data, xid);
5195 : :
5196 : : /*
5197 : : * Make sure there is no forward chain link in t_ctid. Note that in the
5198 : : * cases where the tuple has been updated, we must not overwrite t_ctid,
5199 : : * because it was set by the updater. Moreover, if the tuple has been
5200 : : * updated, we need to follow the update chain to lock the new versions of
5201 : : * the tuple as well.
5202 : : */
4661 alvherre@alvh.no-ip. 5203 [ + + ]: 83255 : if (HEAP_XMAX_IS_LOCKED_ONLY(new_infomask))
5204 : 83216 : tuple->t_data->t_ctid = *tid;
5205 : :
5206 : : /* Clear only the all-frozen bit on visibility map if needed */
3389 andres@anarazel.de 5207 [ + + + + ]: 84921 : if (PageIsAllVisible(page) &&
5208 : 1666 : visibilitymap_clear(relation, block, vmbuffer,
5209 : : VISIBILITYMAP_ALL_FROZEN))
5210 : 14 : cleared_all_frozen = true;
5211 : :
5212 : :
565 akorotkov@postgresql 5213 : 83255 : MarkBufferDirty(*buffer);
5214 : :
5215 : : /*
5216 : : * XLOG stuff. You might think that we don't need an XLOG record because
5217 : : * there is no state change worth restoring after a crash. You would be
5218 : : * wrong however: we have just written either a TransactionId or a
5219 : : * MultiXactId that may never have been seen on disk before, and we need
5220 : : * to make sure that there are XLOG entries covering those ID numbers.
5221 : : * Else the same IDs might be re-used after a crash, which would be
5222 : : * disastrous if this page made it to disk before the crash. Essentially
5223 : : * we have to enforce the WAL log-before-data rule even in this case.
5224 : : * (Also, in a PITR log-shipping or 2PC environment, we have to have XLOG
5225 : : * entries for everything anyway.)
5226 : : */
5433 rhaas@postgresql.org 5227 [ + + + + : 83255 : if (RelationNeedsWAL(relation))
+ - + - ]
5228 : : {
5229 : : xl_heap_lock xlrec;
5230 : : XLogRecPtr recptr;
5231 : :
3995 heikki.linnakangas@i 5232 : 82911 : XLogBeginInsert();
565 akorotkov@postgresql 5233 : 82911 : XLogRegisterBuffer(0, *buffer, REGBUF_STANDARD);
5234 : :
3995 heikki.linnakangas@i 5235 : 82911 : xlrec.offnum = ItemPointerGetOffsetNumber(&tuple->t_self);
931 pg@bowt.ie 5236 : 82911 : xlrec.xmax = xid;
4661 alvherre@alvh.no-ip. 5237 : 165822 : xlrec.infobits_set = compute_infobits(new_infomask,
5238 : 82911 : tuple->t_data->t_infomask2);
3389 andres@anarazel.de 5239 : 82911 : xlrec.flags = cleared_all_frozen ? XLH_LOCK_ALL_FROZEN_CLEARED : 0;
259 peter@eisentraut.org 5240 : 82911 : XLogRegisterData(&xlrec, SizeOfHeapLock);
5241 : :
5242 : : /* we don't decode row locks atm, so no need to log the origin */
5243 : :
3995 heikki.linnakangas@i 5244 : 82911 : recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_LOCK);
5245 : :
6316 tgl@sss.pgh.pa.us 5246 : 82911 : PageSetLSN(page, recptr);
5247 : : }
5248 : :
7488 5249 [ - + ]: 83255 : END_CRIT_SECTION();
5250 : :
2411 andres@anarazel.de 5251 : 83255 : result = TM_Ok;
5252 : :
3389 5253 : 83536 : out_locked:
565 akorotkov@postgresql 5254 : 83536 : LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
5255 : :
3389 andres@anarazel.de 5256 : 85033 : out_unlocked:
5257 [ + + ]: 85033 : if (BufferIsValid(vmbuffer))
5258 : 1666 : ReleaseBuffer(vmbuffer);
5259 : :
5260 : : /*
5261 : : * Don't update the visibility map here. Locking a tuple doesn't change
5262 : : * visibility info.
5263 : : */
5264 : :
5265 : : /*
5266 : : * Now that we have successfully marked the tuple as locked, we can
5267 : : * release the lmgr tuple lock, if we had it.
5268 : : */
7486 tgl@sss.pgh.pa.us 5269 [ + + ]: 85033 : if (have_tuple_lock)
4661 alvherre@alvh.no-ip. 5270 : 153 : UnlockTupleTuplock(relation, tid, mode);
5271 : :
3389 andres@anarazel.de 5272 : 85033 : return result;
5273 : : }
5274 : :
5275 : : /*
5276 : : * Acquire heavyweight lock on the given tuple, in preparation for acquiring
5277 : : * its normal, Xmax-based tuple lock.
5278 : : *
5279 : : * have_tuple_lock is an input and output parameter: on input, it indicates
5280 : : * whether the lock has previously been acquired (and this function does
5281 : : * nothing in that case). If this function returns success, have_tuple_lock
5282 : : * has been flipped to true.
5283 : : *
5284 : : * Returns false if it was unable to obtain the lock; this can only happen if
5285 : : * wait_policy is Skip.
5286 : : */
5287 : : static bool
3959 alvherre@alvh.no-ip. 5288 : 302 : heap_acquire_tuplock(Relation relation, ItemPointer tid, LockTupleMode mode,
5289 : : LockWaitPolicy wait_policy, bool *have_tuple_lock)
5290 : : {
5291 [ + + ]: 302 : if (*have_tuple_lock)
5292 : 9 : return true;
5293 : :
5294 [ + + + - ]: 293 : switch (wait_policy)
5295 : : {
5296 : 252 : case LockWaitBlock:
5297 : 252 : LockTupleTuplock(relation, tid, mode);
5298 : 252 : break;
5299 : :
5300 : 34 : case LockWaitSkip:
228 fujii@postgresql.org 5301 [ + + ]: 34 : if (!ConditionalLockTupleTuplock(relation, tid, mode, false))
3959 alvherre@alvh.no-ip. 5302 : 1 : return false;
5303 : 33 : break;
5304 : :
5305 : 7 : case LockWaitError:
147 fujii@postgresql.org 5306 [ + + ]: 7 : if (!ConditionalLockTupleTuplock(relation, tid, mode, log_lock_failures))
3959 alvherre@alvh.no-ip. 5307 [ + - ]: 1 : ereport(ERROR,
5308 : : (errcode(ERRCODE_LOCK_NOT_AVAILABLE),
5309 : : errmsg("could not obtain lock on row in relation \"%s\"",
5310 : : RelationGetRelationName(relation))));
5311 : 6 : break;
5312 : : }
5313 : 291 : *have_tuple_lock = true;
5314 : :
5315 : 291 : return true;
5316 : : }
5317 : :
5318 : : /*
5319 : : * Given an original set of Xmax and infomask, and a transaction (identified by
5320 : : * add_to_xmax) acquiring a new lock of some mode, compute the new Xmax and
5321 : : * corresponding infomasks to use on the tuple.
5322 : : *
5323 : : * Note that this might have side effects such as creating a new MultiXactId.
5324 : : *
5325 : : * Most callers will have called HeapTupleSatisfiesUpdate before this function;
5326 : : * that will have set the HEAP_XMAX_INVALID bit if the xmax was a MultiXactId
5327 : : * but it was not running anymore. There is a race condition, which is that the
5328 : : * MultiXactId may have finished since then, but that uncommon case is handled
5329 : : * either here, or within MultiXactIdExpand.
5330 : : *
5331 : : * There is a similar race condition possible when the old xmax was a regular
5332 : : * TransactionId. We test TransactionIdIsInProgress again just to narrow the
5333 : : * window, but it's still possible to end up creating an unnecessary
5334 : : * MultiXactId. Fortunately this is harmless.
5335 : : */
5336 : : static void
4661 5337 : 1962412 : compute_new_xmax_infomask(TransactionId xmax, uint16 old_infomask,
5338 : : uint16 old_infomask2, TransactionId add_to_xmax,
5339 : : LockTupleMode mode, bool is_update,
5340 : : TransactionId *result_xmax, uint16 *result_infomask,
5341 : : uint16 *result_infomask2)
5342 : : {
5343 : : TransactionId new_xmax;
5344 : : uint16 new_infomask,
5345 : : new_infomask2;
5346 : :
4331 5347 [ + - ]: 1962412 : Assert(TransactionIdIsCurrentTransactionId(add_to_xmax));
5348 : :
4661 5349 : 2066367 : l5:
5350 : 2066367 : new_infomask = 0;
5351 : 2066367 : new_infomask2 = 0;
5352 [ + + ]: 2066367 : if (old_infomask & HEAP_XMAX_INVALID)
5353 : : {
5354 : : /*
5355 : : * No previous locker; we just insert our own TransactionId.
5356 : : *
5357 : : * Note that it's critical that this case be the first one checked,
5358 : : * because there are several blocks below that come back to this one
5359 : : * to implement certain optimizations; old_infomask might contain
5360 : : * other dirty bits in those cases, but we don't really care.
5361 : : */
5362 [ + + ]: 1961260 : if (is_update)
5363 : : {
5364 : 1729643 : new_xmax = add_to_xmax;
5365 [ + + ]: 1729643 : if (mode == LockTupleExclusive)
5366 : 1461789 : new_infomask2 |= HEAP_KEYS_UPDATED;
5367 : : }
5368 : : else
5369 : : {
5370 : 231617 : new_infomask |= HEAP_XMAX_LOCK_ONLY;
5371 [ + + + + : 231617 : switch (mode)
- ]
5372 : : {
5373 : 2558 : case LockTupleKeyShare:
5374 : 2558 : new_xmax = add_to_xmax;
5375 : 2558 : new_infomask |= HEAP_XMAX_KEYSHR_LOCK;
5376 : 2558 : break;
5377 : 743 : case LockTupleShare:
5378 : 743 : new_xmax = add_to_xmax;
5379 : 743 : new_infomask |= HEAP_XMAX_SHR_LOCK;
5380 : 743 : break;
5381 : 132677 : case LockTupleNoKeyExclusive:
5382 : 132677 : new_xmax = add_to_xmax;
5383 : 132677 : new_infomask |= HEAP_XMAX_EXCL_LOCK;
5384 : 132677 : break;
5385 : 95639 : case LockTupleExclusive:
5386 : 95639 : new_xmax = add_to_xmax;
5387 : 95639 : new_infomask |= HEAP_XMAX_EXCL_LOCK;
5388 : 95639 : new_infomask2 |= HEAP_KEYS_UPDATED;
5389 : 95639 : break;
4661 alvherre@alvh.no-ip. 5390 :UBC 0 : default:
5391 : 0 : new_xmax = InvalidTransactionId; /* silence compiler */
5392 [ # # ]: 0 : elog(ERROR, "invalid lock mode");
5393 : : }
5394 : : }
5395 : : }
4661 alvherre@alvh.no-ip. 5396 [ + + ]:CBC 105107 : else if (old_infomask & HEAP_XMAX_IS_MULTI)
5397 : : {
5398 : : MultiXactStatus new_status;
5399 : :
5400 : : /*
5401 : : * Currently we don't allow XMAX_COMMITTED to be set for multis, so
5402 : : * cross-check.
5403 : : */
5404 [ - + ]: 136 : Assert(!(old_infomask & HEAP_XMAX_COMMITTED));
5405 : :
5406 : : /*
5407 : : * A multixact together with LOCK_ONLY set but neither lock bit set
5408 : : * (i.e. a pg_upgraded share locked tuple) cannot possibly be running
5409 : : * anymore. This check is critical for databases upgraded by
5410 : : * pg_upgrade; both MultiXactIdIsRunning and MultiXactIdExpand assume
5411 : : * that such multis are never passed.
5412 : : */
3413 5413 [ - + ]: 136 : if (HEAP_LOCKED_UPGRADED(old_infomask))
5414 : : {
4661 alvherre@alvh.no-ip. 5415 :UBC 0 : old_infomask &= ~HEAP_XMAX_IS_MULTI;
5416 : 0 : old_infomask |= HEAP_XMAX_INVALID;
5417 : 0 : goto l5;
5418 : : }
5419 : :
5420 : : /*
5421 : : * If the XMAX is already a MultiXactId, then we need to expand it to
5422 : : * include add_to_xmax; but if all the members were lockers and are
5423 : : * all gone, we can do away with the IS_MULTI bit and just set
5424 : : * add_to_xmax as the only locker/updater. If all lockers are gone
5425 : : * and we have an updater that aborted, we can also do without a
5426 : : * multi.
5427 : : *
5428 : : * The cost of doing GetMultiXactIdMembers would be paid by
5429 : : * MultiXactIdExpand if we weren't to do this, so this check is not
5430 : : * incurring extra work anyhow.
5431 : : */
4109 alvherre@alvh.no-ip. 5432 [ + + ]:CBC 136 : if (!MultiXactIdIsRunning(xmax, HEAP_XMAX_IS_LOCKED_ONLY(old_infomask)))
5433 : : {
4661 5434 [ + + ]: 25 : if (HEAP_XMAX_IS_LOCKED_ONLY(old_infomask) ||
3854 5435 [ + - ]: 9 : !TransactionIdDidCommit(MultiXactIdGetUpdateXid(xmax,
5436 : : old_infomask)))
5437 : : {
5438 : : /*
5439 : : * Reset these bits and restart; otherwise fall through to
5440 : : * create a new multi below.
5441 : : */
4661 5442 : 25 : old_infomask &= ~HEAP_XMAX_IS_MULTI;
5443 : 25 : old_infomask |= HEAP_XMAX_INVALID;
5444 : 25 : goto l5;
5445 : : }
5446 : : }
5447 : :
5448 : 111 : new_status = get_mxact_status_for_lock(mode, is_update);
5449 : :
5450 : 111 : new_xmax = MultiXactIdExpand((MultiXactId) xmax, add_to_xmax,
5451 : : new_status);
5452 : 111 : GetMultiXactIdHintBits(new_xmax, &new_infomask, &new_infomask2);
5453 : : }
5454 [ + + ]: 104971 : else if (old_infomask & HEAP_XMAX_COMMITTED)
5455 : : {
5456 : : /*
5457 : : * It's a committed update, so we need to preserve him as updater of
5458 : : * the tuple.
5459 : : */
5460 : : MultiXactStatus status;
5461 : : MultiXactStatus new_status;
5462 : :
5463 [ - + ]: 13 : if (old_infomask2 & HEAP_KEYS_UPDATED)
4661 alvherre@alvh.no-ip. 5464 :UBC 0 : status = MultiXactStatusUpdate;
5465 : : else
4661 alvherre@alvh.no-ip. 5466 :CBC 13 : status = MultiXactStatusNoKeyUpdate;
5467 : :
5468 : 13 : new_status = get_mxact_status_for_lock(mode, is_update);
5469 : :
5470 : : /*
5471 : : * since it's not running, it's obviously impossible for the old
5472 : : * updater to be identical to the current one, so we need not check
5473 : : * for that case as we do in the block above.
5474 : : */
5475 : 13 : new_xmax = MultiXactIdCreate(xmax, status, add_to_xmax, new_status);
5476 : 13 : GetMultiXactIdHintBits(new_xmax, &new_infomask, &new_infomask2);
5477 : : }
5478 [ + + ]: 104958 : else if (TransactionIdIsInProgress(xmax))
5479 : : {
5480 : : /*
5481 : : * If the XMAX is a valid, in-progress TransactionId, then we need to
5482 : : * create a new MultiXactId that includes both the old locker or
5483 : : * updater and our own TransactionId.
5484 : : */
5485 : : MultiXactStatus new_status;
5486 : : MultiXactStatus old_status;
5487 : : LockTupleMode old_mode;
5488 : :
5489 [ + + ]: 104949 : if (HEAP_XMAX_IS_LOCKED_ONLY(old_infomask))
5490 : : {
5491 [ + + ]: 104923 : if (HEAP_XMAX_IS_KEYSHR_LOCKED(old_infomask))
4331 5492 : 5628 : old_status = MultiXactStatusForKeyShare;
4661 5493 [ + + ]: 99295 : else if (HEAP_XMAX_IS_SHR_LOCKED(old_infomask))
4331 5494 : 433 : old_status = MultiXactStatusForShare;
4661 5495 [ + - ]: 98862 : else if (HEAP_XMAX_IS_EXCL_LOCKED(old_infomask))
5496 : : {
5497 [ + + ]: 98862 : if (old_infomask2 & HEAP_KEYS_UPDATED)
4331 5498 : 92720 : old_status = MultiXactStatusForUpdate;
5499 : : else
5500 : 6142 : old_status = MultiXactStatusForNoKeyUpdate;
5501 : : }
5502 : : else
5503 : : {
5504 : : /*
5505 : : * LOCK_ONLY can be present alone only when a page has been
5506 : : * upgraded by pg_upgrade. But in that case,
5507 : : * TransactionIdIsInProgress() should have returned false. We
5508 : : * assume it's no longer locked in this case.
5509 : : */
4661 alvherre@alvh.no-ip. 5510 [ # # ]:UBC 0 : elog(WARNING, "LOCK_ONLY found for Xid in progress %u", xmax);
5511 : 0 : old_infomask |= HEAP_XMAX_INVALID;
5512 : 0 : old_infomask &= ~HEAP_XMAX_LOCK_ONLY;
5513 : 0 : goto l5;
5514 : : }
5515 : : }
5516 : : else
5517 : : {
5518 : : /* it's an update, but which kind? */
4661 alvherre@alvh.no-ip. 5519 [ - + ]:CBC 26 : if (old_infomask2 & HEAP_KEYS_UPDATED)
4331 alvherre@alvh.no-ip. 5520 :UBC 0 : old_status = MultiXactStatusUpdate;
5521 : : else
4331 alvherre@alvh.no-ip. 5522 :CBC 26 : old_status = MultiXactStatusNoKeyUpdate;
5523 : : }
5524 : :
5525 : 104949 : old_mode = TUPLOCK_from_mxstatus(old_status);
5526 : :
5527 : : /*
5528 : : * If the lock to be acquired is for the same TransactionId as the
5529 : : * existing lock, there's an optimization possible: consider only the
5530 : : * strongest of both locks as the only one present, and restart.
5531 : : */
4661 5532 [ + + ]: 104949 : if (xmax == add_to_xmax)
5533 : : {
5534 : : /*
5535 : : * Note that it's not possible for the original tuple to be
5536 : : * updated: we wouldn't be here because the tuple would have been
5537 : : * invisible and we wouldn't try to update it. As a subtlety,
5538 : : * this code can also run when traversing an update chain to lock
5539 : : * future versions of a tuple. But we wouldn't be here either,
5540 : : * because the add_to_xmax would be different from the original
5541 : : * updater.
5542 : : */
4331 5543 [ - + ]: 103922 : Assert(HEAP_XMAX_IS_LOCKED_ONLY(old_infomask));
5544 : :
5545 : : /* acquire the strongest of both */
5546 [ + + ]: 103922 : if (mode < old_mode)
5547 : 52157 : mode = old_mode;
5548 : : /* mustn't touch is_update */
5549 : :
5550 : 103922 : old_infomask |= HEAP_XMAX_INVALID;
5551 : 103922 : goto l5;
5552 : : }
5553 : :
5554 : : /* otherwise, just fall back to creating a new multixact */
5555 : 1027 : new_status = get_mxact_status_for_lock(mode, is_update);
5556 : 1027 : new_xmax = MultiXactIdCreate(xmax, old_status,
5557 : : add_to_xmax, new_status);
4661 5558 : 1027 : GetMultiXactIdHintBits(new_xmax, &new_infomask, &new_infomask2);
5559 : : }
5560 [ + + + + ]: 14 : else if (!HEAP_XMAX_IS_LOCKED_ONLY(old_infomask) &&
5561 : 5 : TransactionIdDidCommit(xmax))
5562 : 1 : {
5563 : : /*
5564 : : * It's a committed update, so we gotta preserve him as updater of the
5565 : : * tuple.
5566 : : */
5567 : : MultiXactStatus status;
5568 : : MultiXactStatus new_status;
5569 : :
5570 [ - + ]: 1 : if (old_infomask2 & HEAP_KEYS_UPDATED)
4661 alvherre@alvh.no-ip. 5571 :UBC 0 : status = MultiXactStatusUpdate;
5572 : : else
4661 alvherre@alvh.no-ip. 5573 :CBC 1 : status = MultiXactStatusNoKeyUpdate;
5574 : :
5575 : 1 : new_status = get_mxact_status_for_lock(mode, is_update);
5576 : :
5577 : : /*
5578 : : * since it's not running, it's obviously impossible for the old
5579 : : * updater to be identical to the current one, so we need not check
5580 : : * for that case as we do in the block above.
5581 : : */
5582 : 1 : new_xmax = MultiXactIdCreate(xmax, status, add_to_xmax, new_status);
5583 : 1 : GetMultiXactIdHintBits(new_xmax, &new_infomask, &new_infomask2);
5584 : : }
5585 : : else
5586 : : {
5587 : : /*
5588 : : * Can get here iff the locking/updating transaction was running when
5589 : : * the infomask was extracted from the tuple, but finished before
5590 : : * TransactionIdIsInProgress got to run. Deal with it as if there was
5591 : : * no locker at all in the first place.
5592 : : */
5593 : 8 : old_infomask |= HEAP_XMAX_INVALID;
5594 : 8 : goto l5;
5595 : : }
5596 : :
5597 : 1962412 : *result_infomask = new_infomask;
5598 : 1962412 : *result_infomask2 = new_infomask2;
5599 : 1962412 : *result_xmax = new_xmax;
5600 : 1962412 : }
5601 : :
5602 : : /*
5603 : : * Subroutine for heap_lock_updated_tuple_rec.
5604 : : *
5605 : : * Given a hypothetical multixact status held by the transaction identified
5606 : : * with the given xid, does the current transaction need to wait, fail, or can
5607 : : * it continue if it wanted to acquire a lock of the given mode? "needwait"
5608 : : * is set to true if waiting is necessary; if it can continue, then TM_Ok is
5609 : : * returned. If the lock is already held by the current transaction, return
5610 : : * TM_SelfModified. In case of a conflict with another transaction, a
5611 : : * different HeapTupleSatisfiesUpdate return code is returned.
5612 : : *
5613 : : * The held status is said to be hypothetical because it might correspond to a
5614 : : * lock held by a single Xid, i.e. not a real MultiXactId; we express it this
5615 : : * way for simplicity of API.
5616 : : */
5617 : : static TM_Result
4353 5618 : 32 : test_lockmode_for_conflict(MultiXactStatus status, TransactionId xid,
5619 : : LockTupleMode mode, HeapTuple tup,
5620 : : bool *needwait)
5621 : : {
5622 : : MultiXactStatus wantedstatus;
5623 : :
5624 : 32 : *needwait = false;
5625 : 32 : wantedstatus = get_mxact_status_for_lock(mode, false);
5626 : :
5627 : : /*
5628 : : * Note: we *must* check TransactionIdIsInProgress before
5629 : : * TransactionIdDidAbort/Commit; see comment at top of heapam_visibility.c
5630 : : * for an explanation.
5631 : : */
5632 [ - + ]: 32 : if (TransactionIdIsCurrentTransactionId(xid))
5633 : : {
5634 : : /*
5635 : : * The tuple has already been locked by our own transaction. This is
5636 : : * very rare but can happen if multiple transactions are trying to
5637 : : * lock an ancient version of the same tuple.
5638 : : */
2411 andres@anarazel.de 5639 :UBC 0 : return TM_SelfModified;
5640 : : }
4353 alvherre@alvh.no-ip. 5641 [ + + ]:CBC 32 : else if (TransactionIdIsInProgress(xid))
5642 : : {
5643 : : /*
5644 : : * If the locking transaction is running, what we do depends on
5645 : : * whether the lock modes conflict: if they do, then we must wait for
5646 : : * it to finish; otherwise we can fall through to lock this tuple
5647 : : * version without waiting.
5648 : : */
5649 [ + + ]: 16 : if (DoLockModesConflict(LOCKMODE_from_mxstatus(status),
5650 : 16 : LOCKMODE_from_mxstatus(wantedstatus)))
5651 : : {
5652 : 8 : *needwait = true;
5653 : : }
5654 : :
5655 : : /*
5656 : : * If we set needwait above, then this value doesn't matter;
5657 : : * otherwise, this value signals to caller that it's okay to proceed.
5658 : : */
2411 andres@anarazel.de 5659 : 16 : return TM_Ok;
5660 : : }
4353 alvherre@alvh.no-ip. 5661 [ + + ]: 16 : else if (TransactionIdDidAbort(xid))
2411 andres@anarazel.de 5662 : 3 : return TM_Ok;
4353 alvherre@alvh.no-ip. 5663 [ + - ]: 13 : else if (TransactionIdDidCommit(xid))
5664 : : {
5665 : : /*
5666 : : * The other transaction committed. If it was only a locker, then the
5667 : : * lock is completely gone now and we can return success; but if it
5668 : : * was an update, then what we do depends on whether the two lock
5669 : : * modes conflict. If they conflict, then we must report error to
5670 : : * caller. But if they don't, we can fall through to allow the current
5671 : : * transaction to lock the tuple.
5672 : : *
5673 : : * Note: the reason we worry about ISUPDATE here is because as soon as
5674 : : * a transaction ends, all its locks are gone and meaningless, and
5675 : : * thus we can ignore them; whereas its updates persist. In the
5676 : : * TransactionIdIsInProgress case, above, we don't need to check
5677 : : * because we know the lock is still "alive" and thus a conflict needs
5678 : : * always be checked.
5679 : : */
4345 5680 [ + + ]: 13 : if (!ISUPDATE_from_mxstatus(status))
2411 andres@anarazel.de 5681 : 4 : return TM_Ok;
5682 : :
4353 alvherre@alvh.no-ip. 5683 [ + + ]: 9 : if (DoLockModesConflict(LOCKMODE_from_mxstatus(status),
5684 : 9 : LOCKMODE_from_mxstatus(wantedstatus)))
5685 : : {
5686 : : /* bummer */
1709 5687 [ + + ]: 8 : if (!ItemPointerEquals(&tup->t_self, &tup->t_data->t_ctid))
2411 andres@anarazel.de 5688 : 6 : return TM_Updated;
5689 : : else
5690 : 2 : return TM_Deleted;
5691 : : }
5692 : :
5693 : 1 : return TM_Ok;
5694 : : }
5695 : :
5696 : : /* Not in progress, not aborted, not committed -- must have crashed */
2411 andres@anarazel.de 5697 :UBC 0 : return TM_Ok;
5698 : : }
5699 : :
5700 : :
5701 : : /*
5702 : : * Recursive part of heap_lock_updated_tuple
5703 : : *
5704 : : * Fetch the tuple pointed to by tid in rel, and mark it as locked by the given
5705 : : * xid with the given mode; if this tuple is updated, recurse to lock the new
5706 : : * version as well.
5707 : : */
5708 : : static TM_Result
4661 alvherre@alvh.no-ip. 5709 :CBC 88 : heap_lock_updated_tuple_rec(Relation rel, ItemPointer tid, TransactionId xid,
5710 : : LockTupleMode mode)
5711 : : {
5712 : : TM_Result result;
5713 : : ItemPointerData tupid;
5714 : : HeapTupleData mytup;
5715 : : Buffer buf;
5716 : : uint16 new_infomask,
5717 : : new_infomask2,
5718 : : old_infomask,
5719 : : old_infomask2;
5720 : : TransactionId xmax,
5721 : : new_xmax;
4353 5722 : 88 : TransactionId priorXmax = InvalidTransactionId;
3389 andres@anarazel.de 5723 : 88 : bool cleared_all_frozen = false;
5724 : : bool pinned_desired_page;
5725 : 88 : Buffer vmbuffer = InvalidBuffer;
5726 : : BlockNumber block;
5727 : :
4661 alvherre@alvh.no-ip. 5728 : 88 : ItemPointerCopy(tid, &tupid);
5729 : :
5730 : : for (;;)
5731 : : {
5732 : 91 : new_infomask = 0;
5733 : 91 : new_xmax = InvalidTransactionId;
3389 andres@anarazel.de 5734 : 91 : block = ItemPointerGetBlockNumber(&tupid);
4661 alvherre@alvh.no-ip. 5735 : 91 : ItemPointerCopy(&tupid, &(mytup.t_self));
5736 : :
1294 tgl@sss.pgh.pa.us 5737 [ + - ]: 91 : if (!heap_fetch(rel, SnapshotAny, &mytup, &buf, false))
5738 : : {
5739 : : /*
5740 : : * if we fail to find the updated version of the tuple, it's
5741 : : * because it was vacuumed/pruned away after its creator
5742 : : * transaction aborted. So behave as if we got to the end of the
5743 : : * chain, and there's no further tuple to lock: return success to
5744 : : * caller.
5745 : : */
2411 andres@anarazel.de 5746 :UBC 0 : result = TM_Ok;
2797 tgl@sss.pgh.pa.us 5747 : 0 : goto out_unlocked;
5748 : : }
5749 : :
4661 alvherre@alvh.no-ip. 5750 :CBC 91 : l4:
5751 [ - + ]: 99 : CHECK_FOR_INTERRUPTS();
5752 : :
5753 : : /*
5754 : : * Before locking the buffer, pin the visibility map page if it
5755 : : * appears to be necessary. Since we haven't got the lock yet,
5756 : : * someone else might be in the middle of changing this, so we'll need
5757 : : * to recheck after we have the lock.
5758 : : */
3389 andres@anarazel.de 5759 [ - + ]: 99 : if (PageIsAllVisible(BufferGetPage(buf)))
5760 : : {
3389 andres@anarazel.de 5761 :UBC 0 : visibilitymap_pin(rel, block, &vmbuffer);
2797 tgl@sss.pgh.pa.us 5762 : 0 : pinned_desired_page = true;
5763 : : }
5764 : : else
2797 tgl@sss.pgh.pa.us 5765 :CBC 99 : pinned_desired_page = false;
5766 : :
4661 alvherre@alvh.no-ip. 5767 : 99 : LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
5768 : :
5769 : : /*
5770 : : * If we didn't pin the visibility map page and the page has become
5771 : : * all visible while we were busy locking the buffer, we'll have to
5772 : : * unlock and re-lock, to avoid holding the buffer lock across I/O.
5773 : : * That's a bit unfortunate, but hopefully shouldn't happen often.
5774 : : *
5775 : : * Note: in some paths through this function, we will reach here
5776 : : * holding a pin on a vm page that may or may not be the one matching
5777 : : * this page. If this page isn't all-visible, we won't use the vm
5778 : : * page, but we hold onto such a pin till the end of the function.
5779 : : */
2797 tgl@sss.pgh.pa.us 5780 [ + - - + ]: 99 : if (!pinned_desired_page && PageIsAllVisible(BufferGetPage(buf)))
5781 : : {
3372 andres@anarazel.de 5782 :UBC 0 : LockBuffer(buf, BUFFER_LOCK_UNLOCK);
5783 : 0 : visibilitymap_pin(rel, block, &vmbuffer);
5784 : 0 : LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
5785 : : }
5786 : :
5787 : : /*
5788 : : * Check the tuple XMIN against prior XMAX, if any. If we reached the
5789 : : * end of the chain, we're done, so return success.
5790 : : */
4353 alvherre@alvh.no-ip. 5791 [ + + - + ]:CBC 102 : if (TransactionIdIsValid(priorXmax) &&
2917 5792 : 3 : !TransactionIdEquals(HeapTupleHeaderGetXmin(mytup.t_data),
5793 : : priorXmax))
5794 : : {
2411 andres@anarazel.de 5795 :UBC 0 : result = TM_Ok;
3389 5796 : 0 : goto out_locked;
5797 : : }
5798 : :
5799 : : /*
5800 : : * Also check Xmin: if this tuple was created by an aborted
5801 : : * (sub)transaction, then we already locked the last live one in the
5802 : : * chain, thus we're done, so return success.
5803 : : */
3336 alvherre@alvh.no-ip. 5804 [ + + ]:CBC 99 : if (TransactionIdDidAbort(HeapTupleHeaderGetXmin(mytup.t_data)))
5805 : : {
2411 andres@anarazel.de 5806 : 13 : result = TM_Ok;
2797 tgl@sss.pgh.pa.us 5807 : 13 : goto out_locked;
5808 : : }
5809 : :
4661 alvherre@alvh.no-ip. 5810 : 86 : old_infomask = mytup.t_data->t_infomask;
4353 5811 : 86 : old_infomask2 = mytup.t_data->t_infomask2;
4661 5812 : 86 : xmax = HeapTupleHeaderGetRawXmax(mytup.t_data);
5813 : :
5814 : : /*
5815 : : * If this tuple version has been updated or locked by some concurrent
5816 : : * transaction(s), what we do depends on whether our lock mode
5817 : : * conflicts with what those other transactions hold, and also on the
5818 : : * status of them.
5819 : : */
4353 5820 [ + + ]: 86 : if (!(old_infomask & HEAP_XMAX_INVALID))
5821 : : {
5822 : : TransactionId rawxmax;
5823 : : bool needwait;
5824 : :
5825 : 30 : rawxmax = HeapTupleHeaderGetRawXmax(mytup.t_data);
5826 [ + + ]: 30 : if (old_infomask & HEAP_XMAX_IS_MULTI)
5827 : : {
5828 : : int nmembers;
5829 : : int i;
5830 : : MultiXactMember *members;
5831 : :
5832 : : /*
5833 : : * We don't need a test for pg_upgrade'd tuples: this is only
5834 : : * applied to tuples after the first in an update chain. Said
5835 : : * first tuple in the chain may well be locked-in-9.2-and-
5836 : : * pg_upgraded, but that one was already locked by our caller,
5837 : : * not us; and any subsequent ones cannot be because our
5838 : : * caller must necessarily have obtained a snapshot later than
5839 : : * the pg_upgrade itself.
5840 : : */
3413 5841 [ - + ]: 1 : Assert(!HEAP_LOCKED_UPGRADED(mytup.t_data->t_infomask));
5842 : :
4109 5843 : 1 : nmembers = GetMultiXactIdMembers(rawxmax, &members, false,
3051 tgl@sss.pgh.pa.us 5844 : 1 : HEAP_XMAX_IS_LOCKED_ONLY(old_infomask));
4353 alvherre@alvh.no-ip. 5845 [ + + ]: 4 : for (i = 0; i < nmembers; i++)
5846 : : {
3389 andres@anarazel.de 5847 : 3 : result = test_lockmode_for_conflict(members[i].status,
5848 : 3 : members[i].xid,
5849 : : mode,
5850 : : &mytup,
5851 : : &needwait);
5852 : :
5853 : : /*
5854 : : * If the tuple was already locked by ourselves in a
5855 : : * previous iteration of this (say heap_lock_tuple was
5856 : : * forced to restart the locking loop because of a change
5857 : : * in xmax), then we hold the lock already on this tuple
5858 : : * version and we don't need to do anything; and this is
5859 : : * not an error condition either. We just need to skip
5860 : : * this tuple and continue locking the next version in the
5861 : : * update chain.
5862 : : */
2411 5863 [ - + ]: 3 : if (result == TM_SelfModified)
5864 : : {
3016 alvherre@alvh.no-ip. 5865 :UBC 0 : pfree(members);
5866 : 0 : goto next;
5867 : : }
5868 : :
4353 alvherre@alvh.no-ip. 5869 [ - + ]:CBC 3 : if (needwait)
5870 : : {
4353 alvherre@alvh.no-ip. 5871 :UBC 0 : LockBuffer(buf, BUFFER_LOCK_UNLOCK);
4241 5872 : 0 : XactLockTableWait(members[i].xid, rel,
5873 : : &mytup.t_self,
5874 : : XLTW_LockUpdated);
4353 5875 : 0 : pfree(members);
5876 : 0 : goto l4;
5877 : : }
2411 andres@anarazel.de 5878 [ - + ]:CBC 3 : if (result != TM_Ok)
5879 : : {
4353 alvherre@alvh.no-ip. 5880 :UBC 0 : pfree(members);
3389 andres@anarazel.de 5881 : 0 : goto out_locked;
5882 : : }
5883 : : }
4353 alvherre@alvh.no-ip. 5884 [ + - ]:CBC 1 : if (members)
5885 : 1 : pfree(members);
5886 : : }
5887 : : else
5888 : : {
5889 : : MultiXactStatus status;
5890 : :
5891 : : /*
5892 : : * For a non-multi Xmax, we first need to compute the
5893 : : * corresponding MultiXactStatus by using the infomask bits.
5894 : : */
5895 [ + + ]: 29 : if (HEAP_XMAX_IS_LOCKED_ONLY(old_infomask))
5896 : : {
5897 [ + - ]: 10 : if (HEAP_XMAX_IS_KEYSHR_LOCKED(old_infomask))
5898 : 10 : status = MultiXactStatusForKeyShare;
4353 alvherre@alvh.no-ip. 5899 [ # # ]:UBC 0 : else if (HEAP_XMAX_IS_SHR_LOCKED(old_infomask))
5900 : 0 : status = MultiXactStatusForShare;
5901 [ # # ]: 0 : else if (HEAP_XMAX_IS_EXCL_LOCKED(old_infomask))
5902 : : {
5903 [ # # ]: 0 : if (old_infomask2 & HEAP_KEYS_UPDATED)
5904 : 0 : status = MultiXactStatusForUpdate;
5905 : : else
5906 : 0 : status = MultiXactStatusForNoKeyUpdate;
5907 : : }
5908 : : else
5909 : : {
5910 : : /*
5911 : : * LOCK_ONLY present alone (a pg_upgraded tuple marked
5912 : : * as share-locked in the old cluster) shouldn't be
5913 : : * seen in the middle of an update chain.
5914 : : */
5915 [ # # ]: 0 : elog(ERROR, "invalid lock status in tuple");
5916 : : }
5917 : : }
5918 : : else
5919 : : {
5920 : : /* it's an update, but which kind? */
4353 alvherre@alvh.no-ip. 5921 [ + + ]:CBC 19 : if (old_infomask2 & HEAP_KEYS_UPDATED)
5922 : 14 : status = MultiXactStatusUpdate;
5923 : : else
5924 : 5 : status = MultiXactStatusNoKeyUpdate;
5925 : : }
5926 : :
3389 andres@anarazel.de 5927 : 29 : result = test_lockmode_for_conflict(status, rawxmax, mode,
5928 : : &mytup, &needwait);
5929 : :
5930 : : /*
5931 : : * If the tuple was already locked by ourselves in a previous
5932 : : * iteration of this (say heap_lock_tuple was forced to
5933 : : * restart the locking loop because of a change in xmax), then
5934 : : * we hold the lock already on this tuple version and we don't
5935 : : * need to do anything; and this is not an error condition
5936 : : * either. We just need to skip this tuple and continue
5937 : : * locking the next version in the update chain.
5938 : : */
2411 5939 [ - + ]: 29 : if (result == TM_SelfModified)
3016 alvherre@alvh.no-ip. 5940 :UBC 0 : goto next;
5941 : :
4353 alvherre@alvh.no-ip. 5942 [ + + ]:CBC 29 : if (needwait)
5943 : : {
5944 : 8 : LockBuffer(buf, BUFFER_LOCK_UNLOCK);
3919 heikki.linnakangas@i 5945 : 8 : XactLockTableWait(rawxmax, rel, &mytup.t_self,
5946 : : XLTW_LockUpdated);
4353 alvherre@alvh.no-ip. 5947 : 8 : goto l4;
5948 : : }
2411 andres@anarazel.de 5949 [ + + ]: 21 : if (result != TM_Ok)
5950 : : {
3389 5951 : 8 : goto out_locked;
5952 : : }
5953 : : }
5954 : : }
5955 : :
5956 : : /* compute the new Xmax and infomask values for the tuple ... */
4661 alvherre@alvh.no-ip. 5957 : 70 : compute_new_xmax_infomask(xmax, old_infomask, mytup.t_data->t_infomask2,
5958 : : xid, mode, false,
5959 : : &new_xmax, &new_infomask, &new_infomask2);
5960 : :
3389 andres@anarazel.de 5961 [ - + - - ]: 70 : if (PageIsAllVisible(BufferGetPage(buf)) &&
3389 andres@anarazel.de 5962 :UBC 0 : visibilitymap_clear(rel, block, vmbuffer,
5963 : : VISIBILITYMAP_ALL_FROZEN))
5964 : 0 : cleared_all_frozen = true;
5965 : :
4661 alvherre@alvh.no-ip. 5966 :CBC 70 : START_CRIT_SECTION();
5967 : :
5968 : : /* ... and set them */
5969 : 70 : HeapTupleHeaderSetXmax(mytup.t_data, new_xmax);
5970 : 70 : mytup.t_data->t_infomask &= ~HEAP_XMAX_BITS;
5971 : 70 : mytup.t_data->t_infomask2 &= ~HEAP_KEYS_UPDATED;
5972 : 70 : mytup.t_data->t_infomask |= new_infomask;
5973 : 70 : mytup.t_data->t_infomask2 |= new_infomask2;
5974 : :
5975 : 70 : MarkBufferDirty(buf);
5976 : :
5977 : : /* XLOG stuff */
5978 [ + - - + : 70 : if (RelationNeedsWAL(rel))
- - - - ]
5979 : : {
5980 : : xl_heap_lock_updated xlrec;
5981 : : XLogRecPtr recptr;
3478 kgrittn@postgresql.o 5982 : 70 : Page page = BufferGetPage(buf);
5983 : :
3995 heikki.linnakangas@i 5984 : 70 : XLogBeginInsert();
5985 : 70 : XLogRegisterBuffer(0, buf, REGBUF_STANDARD);
5986 : :
5987 : 70 : xlrec.offnum = ItemPointerGetOffsetNumber(&mytup.t_self);
4661 alvherre@alvh.no-ip. 5988 : 70 : xlrec.xmax = new_xmax;
5989 : 70 : xlrec.infobits_set = compute_infobits(new_infomask, new_infomask2);
3389 andres@anarazel.de 5990 : 70 : xlrec.flags =
5991 : 70 : cleared_all_frozen ? XLH_LOCK_ALL_FROZEN_CLEARED : 0;
5992 : :
259 peter@eisentraut.org 5993 : 70 : XLogRegisterData(&xlrec, SizeOfHeapLockUpdated);
5994 : :
3995 heikki.linnakangas@i 5995 : 70 : recptr = XLogInsert(RM_HEAP2_ID, XLOG_HEAP2_LOCK_UPDATED);
5996 : :
4661 alvherre@alvh.no-ip. 5997 : 70 : PageSetLSN(page, recptr);
5998 : : }
5999 : :
6000 [ - + ]: 70 : END_CRIT_SECTION();
6001 : :
3016 6002 : 70 : next:
6003 : : /* if we find the end of update chain, we're done. */
4661 6004 [ + - + - ]: 140 : if (mytup.t_data->t_infomask & HEAP_XMAX_INVALID ||
2761 andres@anarazel.de 6005 [ + + ]: 140 : HeapTupleHeaderIndicatesMovedPartitions(mytup.t_data) ||
4535 bruce@momjian.us 6006 [ + + ]: 74 : ItemPointerEquals(&mytup.t_self, &mytup.t_data->t_ctid) ||
4661 alvherre@alvh.no-ip. 6007 : 4 : HeapTupleHeaderIsOnlyLocked(mytup.t_data))
6008 : : {
2411 andres@anarazel.de 6009 : 67 : result = TM_Ok;
3389 6010 : 67 : goto out_locked;
6011 : : }
6012 : :
6013 : : /* tail recursion */
4353 alvherre@alvh.no-ip. 6014 : 3 : priorXmax = HeapTupleHeaderGetUpdateXid(mytup.t_data);
4661 6015 : 3 : ItemPointerCopy(&(mytup.t_data->t_ctid), &tupid);
6016 : 3 : UnlockReleaseBuffer(buf);
6017 : : }
6018 : :
6019 : : result = TM_Ok;
6020 : :
3389 andres@anarazel.de 6021 : 88 : out_locked:
6022 : 88 : UnlockReleaseBuffer(buf);
6023 : :
2797 tgl@sss.pgh.pa.us 6024 : 88 : out_unlocked:
3389 andres@anarazel.de 6025 [ - + ]: 88 : if (vmbuffer != InvalidBuffer)
3389 andres@anarazel.de 6026 :UBC 0 : ReleaseBuffer(vmbuffer);
6027 : :
3389 andres@anarazel.de 6028 :CBC 88 : return result;
6029 : : }
6030 : :
6031 : : /*
6032 : : * heap_lock_updated_tuple
6033 : : * Follow update chain when locking an updated tuple, acquiring locks (row
6034 : : * marks) on the updated versions.
6035 : : *
6036 : : * The initial tuple is assumed to be already locked.
6037 : : *
6038 : : * This function doesn't check visibility, it just unconditionally marks the
6039 : : * tuple(s) as locked. If any tuple in the updated chain is being deleted
6040 : : * concurrently (or updated with the key being modified), sleep until the
6041 : : * transaction doing it is finished.
6042 : : *
6043 : : * Note that we don't acquire heavyweight tuple locks on the tuples we walk
6044 : : * when we have to wait for other transactions to release them, as opposed to
6045 : : * what heap_lock_tuple does. The reason is that having more than one
6046 : : * transaction walking the chain is probably uncommon enough that risk of
6047 : : * starvation is not likely: one of the preconditions for being here is that
6048 : : * the snapshot in use predates the update that created this tuple (because we
6049 : : * started at an earlier version of the tuple), but at the same time such a
6050 : : * transaction cannot be using repeatable read or serializable isolation
6051 : : * levels, because that would lead to a serializability failure.
6052 : : */
6053 : : static TM_Result
4661 alvherre@alvh.no-ip. 6054 : 105 : heap_lock_updated_tuple(Relation rel, HeapTuple tuple, ItemPointer ctid,
6055 : : TransactionId xid, LockTupleMode mode)
6056 : : {
6057 : : /*
6058 : : * If the tuple has not been updated, or has moved into another partition
6059 : : * (effectively a delete) stop here.
6060 : : */
2761 andres@anarazel.de 6061 [ + + ]: 105 : if (!HeapTupleHeaderIndicatesMovedPartitions(tuple->t_data) &&
6062 [ + + ]: 103 : !ItemPointerEquals(&tuple->t_self, ctid))
6063 : : {
6064 : : /*
6065 : : * If this is the first possibly-multixact-able operation in the
6066 : : * current transaction, set my per-backend OldestMemberMXactId
6067 : : * setting. We can be certain that the transaction will never become a
6068 : : * member of any older MultiXactIds than that. (We have to do this
6069 : : * even if we end up just using our own TransactionId below, since
6070 : : * some other backend could incorporate our XID into a MultiXact
6071 : : * immediately afterwards.)
6072 : : */
4661 alvherre@alvh.no-ip. 6073 : 88 : MultiXactIdSetOldestMember();
6074 : :
6075 : 88 : return heap_lock_updated_tuple_rec(rel, ctid, xid, mode);
6076 : : }
6077 : :
6078 : : /* nothing to lock */
2411 andres@anarazel.de 6079 : 17 : return TM_Ok;
6080 : : }
6081 : :
6082 : : /*
6083 : : * heap_finish_speculative - mark speculative insertion as successful
6084 : : *
6085 : : * To successfully finish a speculative insertion we have to clear speculative
6086 : : * token from tuple. To do so the t_ctid field, which will contain a
6087 : : * speculative token value, is modified in place to point to the tuple itself,
6088 : : * which is characteristic of a newly inserted ordinary tuple.
6089 : : *
6090 : : * NB: It is not ok to commit without either finishing or aborting a
6091 : : * speculative insertion. We could treat speculative tuples of committed
6092 : : * transactions implicitly as completed, but then we would have to be prepared
6093 : : * to deal with speculative tokens on committed tuples. That wouldn't be
6094 : : * difficult - no-one looks at the ctid field of a tuple with invalid xmax -
6095 : : * but clearing the token at completion isn't very expensive either.
6096 : : * An explicit confirmation WAL record also makes logical decoding simpler.
6097 : : */
6098 : : void
6099 : 2071 : heap_finish_speculative(Relation relation, ItemPointer tid)
6100 : : {
6101 : : Buffer buffer;
6102 : : Page page;
6103 : : OffsetNumber offnum;
3826 6104 : 2071 : ItemId lp = NULL;
6105 : : HeapTupleHeader htup;
6106 : :
2411 6107 : 2071 : buffer = ReadBuffer(relation, ItemPointerGetBlockNumber(tid));
3826 6108 : 2071 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
60 peter@eisentraut.org 6109 :GNC 2071 : page = BufferGetPage(buffer);
6110 : :
2411 andres@anarazel.de 6111 :CBC 2071 : offnum = ItemPointerGetOffsetNumber(tid);
3826 6112 [ + - ]: 2071 : if (PageGetMaxOffsetNumber(page) >= offnum)
6113 : 2071 : lp = PageGetItemId(page, offnum);
6114 : :
6115 [ + - - + ]: 2071 : if (PageGetMaxOffsetNumber(page) < offnum || !ItemIdIsNormal(lp))
3631 andres@anarazel.de 6116 [ # # ]:UBC 0 : elog(ERROR, "invalid lp");
6117 : :
3826 andres@anarazel.de 6118 :CBC 2071 : htup = (HeapTupleHeader) PageGetItem(page, lp);
6119 : :
6120 : : /* NO EREPORT(ERROR) from here till changes are logged */
6121 : 2071 : START_CRIT_SECTION();
6122 : :
2411 6123 [ - + ]: 2071 : Assert(HeapTupleHeaderIsSpeculative(htup));
6124 : :
3826 6125 : 2071 : MarkBufferDirty(buffer);
6126 : :
6127 : : /*
6128 : : * Replace the speculative insertion token with a real t_ctid, pointing to
6129 : : * itself like it does on regular tuples.
6130 : : */
2411 6131 : 2071 : htup->t_ctid = *tid;
6132 : :
6133 : : /* XLOG stuff */
3826 6134 [ + + + + : 2071 : if (RelationNeedsWAL(relation))
+ - + - ]
6135 : : {
6136 : : xl_heap_confirm xlrec;
6137 : : XLogRecPtr recptr;
6138 : :
2411 6139 : 2062 : xlrec.offnum = ItemPointerGetOffsetNumber(tid);
6140 : :
3826 6141 : 2062 : XLogBeginInsert();
6142 : :
6143 : : /* We want the same filtering on this as on a plain insert */
3232 6144 : 2062 : XLogSetRecordFlags(XLOG_INCLUDE_ORIGIN);
6145 : :
259 peter@eisentraut.org 6146 : 2062 : XLogRegisterData(&xlrec, SizeOfHeapConfirm);
3826 andres@anarazel.de 6147 : 2062 : XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
6148 : :
6149 : 2062 : recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_CONFIRM);
6150 : :
6151 : 2062 : PageSetLSN(page, recptr);
6152 : : }
6153 : :
6154 [ - + ]: 2071 : END_CRIT_SECTION();
6155 : :
6156 : 2071 : UnlockReleaseBuffer(buffer);
6157 : 2071 : }
6158 : :
6159 : : /*
6160 : : * heap_abort_speculative - kill a speculatively inserted tuple
6161 : : *
6162 : : * Marks a tuple that was speculatively inserted in the same command as dead,
6163 : : * by setting its xmin as invalid. That makes it immediately appear as dead
6164 : : * to all transactions, including our own. In particular, it makes
6165 : : * HeapTupleSatisfiesDirty() regard the tuple as dead, so that another backend
6166 : : * inserting a duplicate key value won't unnecessarily wait for our whole
6167 : : * transaction to finish (it'll just wait for our speculative insertion to
6168 : : * finish).
6169 : : *
6170 : : * Killing the tuple prevents "unprincipled deadlocks", which are deadlocks
6171 : : * that arise due to a mutual dependency that is not user visible. By
6172 : : * definition, unprincipled deadlocks cannot be prevented by the user
6173 : : * reordering lock acquisition in client code, because the implementation level
6174 : : * lock acquisitions are not under the user's direct control. If speculative
6175 : : * inserters did not take this precaution, then under high concurrency they
6176 : : * could deadlock with each other, which would not be acceptable.
6177 : : *
6178 : : * This is somewhat redundant with heap_delete, but we prefer to have a
6179 : : * dedicated routine with stripped down requirements. Note that this is also
6180 : : * used to delete the TOAST tuples created during speculative insertion.
6181 : : *
6182 : : * This routine does not affect logical decoding as it only looks at
6183 : : * confirmation records.
6184 : : */
6185 : : void
2411 6186 : 10 : heap_abort_speculative(Relation relation, ItemPointer tid)
6187 : : {
3826 6188 : 10 : TransactionId xid = GetCurrentTransactionId();
6189 : : ItemId lp;
6190 : : HeapTupleData tp;
6191 : : Page page;
6192 : : BlockNumber block;
6193 : : Buffer buffer;
6194 : :
6195 [ - + ]: 10 : Assert(ItemPointerIsValid(tid));
6196 : :
6197 : 10 : block = ItemPointerGetBlockNumber(tid);
6198 : 10 : buffer = ReadBuffer(relation, block);
3478 kgrittn@postgresql.o 6199 : 10 : page = BufferGetPage(buffer);
6200 : :
3826 andres@anarazel.de 6201 : 10 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
6202 : :
6203 : : /*
6204 : : * Page can't be all visible, we just inserted into it, and are still
6205 : : * running.
6206 : : */
6207 [ - + ]: 10 : Assert(!PageIsAllVisible(page));
6208 : :
6209 : 10 : lp = PageGetItemId(page, ItemPointerGetOffsetNumber(tid));
6210 [ - + ]: 10 : Assert(ItemIdIsNormal(lp));
6211 : :
6212 : 10 : tp.t_tableOid = RelationGetRelid(relation);
6213 : 10 : tp.t_data = (HeapTupleHeader) PageGetItem(page, lp);
6214 : 10 : tp.t_len = ItemIdGetLength(lp);
6215 : 10 : tp.t_self = *tid;
6216 : :
6217 : : /*
6218 : : * Sanity check that the tuple really is a speculatively inserted tuple,
6219 : : * inserted by us.
6220 : : */
6221 [ - + ]: 10 : if (tp.t_data->t_choice.t_heap.t_xmin != xid)
3826 andres@anarazel.de 6222 [ # # ]:UBC 0 : elog(ERROR, "attempted to kill a tuple inserted by another transaction");
3359 andres@anarazel.de 6223 [ + + - + ]:CBC 10 : if (!(IsToastRelation(relation) || HeapTupleHeaderIsSpeculative(tp.t_data)))
3826 andres@anarazel.de 6224 [ # # ]:UBC 0 : elog(ERROR, "attempted to kill a non-speculative tuple");
3826 andres@anarazel.de 6225 [ - + ]:CBC 10 : Assert(!HeapTupleHeaderIsHeapOnly(tp.t_data));
6226 : :
6227 : : /*
6228 : : * No need to check for serializable conflicts here. There is never a
6229 : : * need for a combo CID, either. No need to extract replica identity, or
6230 : : * do anything special with infomask bits.
6231 : : */
6232 : :
6233 : 10 : START_CRIT_SECTION();
6234 : :
6235 : : /*
6236 : : * The tuple will become DEAD immediately. Flag that this page is a
6237 : : * candidate for pruning by setting xmin to TransactionXmin. While not
6238 : : * immediately prunable, it is the oldest xid we can cheaply determine
6239 : : * that's safe against wraparound / being older than the table's
6240 : : * relfrozenxid. To defend against the unlikely case of a new relation
6241 : : * having a newer relfrozenxid than our TransactionXmin, use relfrozenxid
6242 : : * if so (vacuum can't subsequently move relfrozenxid to beyond
6243 : : * TransactionXmin, so there's no race here).
6244 : : */
2032 6245 [ - + ]: 10 : Assert(TransactionIdIsValid(TransactionXmin));
6246 : : {
547 noah@leadboat.com 6247 : 10 : TransactionId relfrozenxid = relation->rd_rel->relfrozenxid;
6248 : : TransactionId prune_xid;
6249 : :
6250 [ - + ]: 10 : if (TransactionIdPrecedes(TransactionXmin, relfrozenxid))
547 noah@leadboat.com 6251 :UBC 0 : prune_xid = relfrozenxid;
6252 : : else
547 noah@leadboat.com 6253 :CBC 10 : prune_xid = TransactionXmin;
6254 [ - + + + : 10 : PageSetPrunable(page, prune_xid);
- + ]
6255 : : }
6256 : :
6257 : : /* store transaction information of xact deleting the tuple */
3826 andres@anarazel.de 6258 : 10 : tp.t_data->t_infomask &= ~(HEAP_XMAX_BITS | HEAP_MOVED);
6259 : 10 : tp.t_data->t_infomask2 &= ~HEAP_KEYS_UPDATED;
6260 : :
6261 : : /*
6262 : : * Set the tuple header xmin to InvalidTransactionId. This makes the
6263 : : * tuple immediately invisible everyone. (In particular, to any
6264 : : * transactions waiting on the speculative token, woken up later.)
6265 : : */
6266 : 10 : HeapTupleHeaderSetXmin(tp.t_data, InvalidTransactionId);
6267 : :
6268 : : /* Clear the speculative insertion token too */
6269 : 10 : tp.t_data->t_ctid = tp.t_self;
6270 : :
6271 : 10 : MarkBufferDirty(buffer);
6272 : :
6273 : : /*
6274 : : * XLOG stuff
6275 : : *
6276 : : * The WAL records generated here match heap_delete(). The same recovery
6277 : : * routines are used.
6278 : : */
6279 [ + - - + : 10 : if (RelationNeedsWAL(relation))
- - - - ]
6280 : : {
6281 : : xl_heap_delete xlrec;
6282 : : XLogRecPtr recptr;
6283 : :
6284 : 10 : xlrec.flags = XLH_DELETE_IS_SUPER;
6285 : 20 : xlrec.infobits_set = compute_infobits(tp.t_data->t_infomask,
6286 : 10 : tp.t_data->t_infomask2);
6287 : 10 : xlrec.offnum = ItemPointerGetOffsetNumber(&tp.t_self);
6288 : 10 : xlrec.xmax = xid;
6289 : :
6290 : 10 : XLogBeginInsert();
259 peter@eisentraut.org 6291 : 10 : XLogRegisterData(&xlrec, SizeOfHeapDelete);
3826 andres@anarazel.de 6292 : 10 : XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
6293 : :
6294 : : /* No replica identity & replication origin logged */
6295 : :
6296 : 10 : recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_DELETE);
6297 : :
6298 : 10 : PageSetLSN(page, recptr);
6299 : : }
6300 : :
6301 [ - + ]: 10 : END_CRIT_SECTION();
6302 : :
6303 : 10 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
6304 : :
6305 [ + + ]: 10 : if (HeapTupleHasExternal(&tp))
6306 : : {
3359 6307 [ - + ]: 1 : Assert(!IsToastRelation(relation));
2216 rhaas@postgresql.org 6308 : 1 : heap_toast_delete(relation, &tp, true);
6309 : : }
6310 : :
6311 : : /*
6312 : : * Never need to mark tuple for invalidation, since catalogs don't support
6313 : : * speculative insertion
6314 : : */
6315 : :
6316 : : /* Now we can release the buffer */
3826 andres@anarazel.de 6317 : 10 : ReleaseBuffer(buffer);
6318 : :
6319 : : /* count deletion, as we counted the insertion too */
6320 : 10 : pgstat_count_heap_delete(relation);
6321 : 10 : }
6322 : :
6323 : : /*
6324 : : * heap_inplace_lock - protect inplace update from concurrent heap_update()
6325 : : *
6326 : : * Evaluate whether the tuple's state is compatible with a no-key update.
6327 : : * Current transaction rowmarks are fine, as is KEY SHARE from any
6328 : : * transaction. If compatible, return true with the buffer exclusive-locked,
6329 : : * and the caller must release that by calling
6330 : : * heap_inplace_update_and_unlock(), calling heap_inplace_unlock(), or raising
6331 : : * an error. Otherwise, call release_callback(arg), wait for blocking
6332 : : * transactions to end, and return false.
6333 : : *
6334 : : * Since this is intended for system catalogs and SERIALIZABLE doesn't cover
6335 : : * DDL, this doesn't guarantee any particular predicate locking.
6336 : : *
6337 : : * One could modify this to return true for tuples with delete in progress,
6338 : : * All inplace updaters take a lock that conflicts with DROP. If explicit
6339 : : * "DELETE FROM pg_class" is in progress, we'll wait for it like we would an
6340 : : * update.
6341 : : *
6342 : : * Readers of inplace-updated fields expect changes to those fields are
6343 : : * durable. For example, vac_truncate_clog() reads datfrozenxid from
6344 : : * pg_database tuples via catalog snapshots. A future snapshot must not
6345 : : * return a lower datfrozenxid for the same database OID (lower in the
6346 : : * FullTransactionIdPrecedes() sense). We achieve that since no update of a
6347 : : * tuple can start while we hold a lock on its buffer. In cases like
6348 : : * BEGIN;GRANT;CREATE INDEX;COMMIT we're inplace-updating a tuple visible only
6349 : : * to this transaction. ROLLBACK then is one case where it's okay to lose
6350 : : * inplace updates. (Restoring relhasindex=false on ROLLBACK is fine, since
6351 : : * any concurrent CREATE INDEX would have blocked, then inplace-updated the
6352 : : * committed tuple.)
6353 : : *
6354 : : * In principle, we could avoid waiting by overwriting every tuple in the
6355 : : * updated tuple chain. Reader expectations permit updating a tuple only if
6356 : : * it's aborted, is the tail of the chain, or we already updated the tuple
6357 : : * referenced in its t_ctid. Hence, we would need to overwrite the tuples in
6358 : : * order from tail to head. That would imply either (a) mutating all tuples
6359 : : * in one critical section or (b) accepting a chance of partial completion.
6360 : : * Partial completion of a relfrozenxid update would have the weird
6361 : : * consequence that the table's next VACUUM could see the table's relfrozenxid
6362 : : * move forward between vacuum_get_cutoffs() and finishing.
6363 : : */
6364 : : bool
399 noah@leadboat.com 6365 : 91649 : heap_inplace_lock(Relation relation,
6366 : : HeapTuple oldtup_ptr, Buffer buffer,
6367 : : void (*release_callback) (void *), void *arg)
6368 : : {
6369 : 91649 : HeapTupleData oldtup = *oldtup_ptr; /* minimize diff vs. heap_update() */
6370 : : TM_Result result;
6371 : : bool ret;
6372 : :
6373 : : #ifdef USE_ASSERT_CHECKING
6374 [ + + ]: 91649 : if (RelationGetRelid(relation) == RelationRelationId)
6375 : 90708 : check_inplace_rel_lock(oldtup_ptr);
6376 : : #endif
6377 : :
6378 [ - + ]: 91649 : Assert(BufferIsValid(buffer));
6379 : :
6380 : : /*
6381 : : * Construct shared cache inval if necessary. Because we pass a tuple
6382 : : * version without our own inplace changes or inplace changes other
6383 : : * sessions complete while we wait for locks, inplace update mustn't
6384 : : * change catcache lookup keys. But we aren't bothering with index
6385 : : * updates either, so that's true a fortiori. After LockBuffer(), it
6386 : : * would be too late, because this might reach a
6387 : : * CatalogCacheInitializeCache() that locks "buffer".
6388 : : */
360 6389 : 91649 : CacheInvalidateHeapTupleInplace(relation, oldtup_ptr, NULL);
6390 : :
399 6391 : 91649 : LockTuple(relation, &oldtup.t_self, InplaceUpdateTupleLock);
6392 : 91649 : LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
6393 : :
6394 : : /*----------
6395 : : * Interpret HeapTupleSatisfiesUpdate() like heap_update() does, except:
6396 : : *
6397 : : * - wait unconditionally
6398 : : * - already locked tuple above, since inplace needs that unconditionally
6399 : : * - don't recheck header after wait: simpler to defer to next iteration
6400 : : * - don't try to continue even if the updater aborts: likewise
6401 : : * - no crosscheck
6402 : : */
6403 : 91649 : result = HeapTupleSatisfiesUpdate(&oldtup, GetCurrentCommandId(false),
6404 : : buffer);
6405 : :
6406 [ - + ]: 91649 : if (result == TM_Invisible)
6407 : : {
6408 : : /* no known way this can happen */
3834 rhaas@postgresql.org 6409 [ # # ]:UBC 0 : ereport(ERROR,
6410 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
6411 : : errmsg_internal("attempted to overwrite invisible tuple")));
6412 : : }
399 noah@leadboat.com 6413 [ - + ]:CBC 91649 : else if (result == TM_SelfModified)
6414 : : {
6415 : : /*
6416 : : * CREATE INDEX might reach this if an expression is silly enough to
6417 : : * call e.g. SELECT ... FROM pg_class FOR SHARE. C code of other SQL
6418 : : * statements might get here after a heap_update() of the same row, in
6419 : : * the absence of an intervening CommandCounterIncrement().
6420 : : */
399 noah@leadboat.com 6421 [ # # ]:UBC 0 : ereport(ERROR,
6422 : : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
6423 : : errmsg("tuple to be updated was already modified by an operation triggered by the current command")));
6424 : : }
399 noah@leadboat.com 6425 [ + + ]:CBC 91649 : else if (result == TM_BeingModified)
6426 : : {
6427 : : TransactionId xwait;
6428 : : uint16 infomask;
6429 : :
6430 : 62 : xwait = HeapTupleHeaderGetRawXmax(oldtup.t_data);
6431 : 62 : infomask = oldtup.t_data->t_infomask;
6432 : :
6433 [ + + ]: 62 : if (infomask & HEAP_XMAX_IS_MULTI)
6434 : : {
6435 : 5 : LockTupleMode lockmode = LockTupleNoKeyExclusive;
6436 : 5 : MultiXactStatus mxact_status = MultiXactStatusNoKeyUpdate;
6437 : : int remain;
6438 : :
6439 [ + + ]: 5 : if (DoesMultiXactIdConflict((MultiXactId) xwait, infomask,
6440 : : lockmode, NULL))
6441 : : {
6442 : 2 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
364 6443 : 2 : release_callback(arg);
399 6444 : 2 : ret = false;
6445 : 2 : MultiXactIdWait((MultiXactId) xwait, mxact_status, infomask,
6446 : : relation, &oldtup.t_self, XLTW_Update,
6447 : : &remain);
6448 : : }
6449 : : else
6450 : 3 : ret = true;
6451 : : }
6452 [ + + ]: 57 : else if (TransactionIdIsCurrentTransactionId(xwait))
6453 : 1 : ret = true;
6454 [ + + ]: 56 : else if (HEAP_XMAX_IS_KEYSHR_LOCKED(infomask))
6455 : 1 : ret = true;
6456 : : else
6457 : : {
6458 : 55 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
364 6459 : 55 : release_callback(arg);
399 6460 : 55 : ret = false;
6461 : 55 : XactLockTableWait(xwait, relation, &oldtup.t_self,
6462 : : XLTW_Update);
6463 : : }
6464 : : }
6465 : : else
6466 : : {
6467 : 91587 : ret = (result == TM_Ok);
6468 [ + + ]: 91587 : if (!ret)
6469 : : {
399 noah@leadboat.com 6470 :GBC 1 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
364 6471 : 1 : release_callback(arg);
6472 : : }
6473 : : }
6474 : :
6475 : : /*
6476 : : * GetCatalogSnapshot() relies on invalidation messages to know when to
6477 : : * take a new snapshot. COMMIT of xwait is responsible for sending the
6478 : : * invalidation. We're not acquiring heavyweight locks sufficient to
6479 : : * block if not yet sent, so we must take a new snapshot to ensure a later
6480 : : * attempt has a fair chance. While we don't need this if xwait aborted,
6481 : : * don't bother optimizing that.
6482 : : */
399 noah@leadboat.com 6483 [ + + ]:CBC 91649 : if (!ret)
6484 : : {
6485 : 58 : UnlockTuple(relation, &oldtup.t_self, InplaceUpdateTupleLock);
360 6486 : 58 : ForgetInplace_Inval();
399 6487 : 58 : InvalidateCatalogSnapshot();
6488 : : }
6489 : 91649 : return ret;
6490 : : }
6491 : :
6492 : : /*
6493 : : * heap_inplace_update_and_unlock - core of systable_inplace_update_finish
6494 : : *
6495 : : * The tuple cannot change size, and therefore its header fields and null
6496 : : * bitmap (if any) don't change either.
6497 : : *
6498 : : * Since we hold LOCKTAG_TUPLE, no updater has a local copy of this tuple.
6499 : : */
6500 : : void
6501 : 63376 : heap_inplace_update_and_unlock(Relation relation,
6502 : : HeapTuple oldtup, HeapTuple tuple,
6503 : : Buffer buffer)
6504 : : {
6505 : 63376 : HeapTupleHeader htup = oldtup->t_data;
6506 : : uint32 oldlen;
6507 : : uint32 newlen;
6508 : : char *dst;
6509 : : char *src;
368 6510 : 63376 : int nmsgs = 0;
6511 : 63376 : SharedInvalidationMessage *invalMessages = NULL;
6512 : 63376 : bool RelcacheInitFileInval = false;
6513 : :
399 6514 [ - + ]: 63376 : Assert(ItemPointerEquals(&oldtup->t_self, &tuple->t_self));
6515 : 63376 : oldlen = oldtup->t_len - htup->t_hoff;
7111 tgl@sss.pgh.pa.us 6516 : 63376 : newlen = tuple->t_len - tuple->t_data->t_hoff;
6517 [ + - - + ]: 63376 : if (oldlen != newlen || htup->t_hoff != tuple->t_data->t_hoff)
3631 andres@anarazel.de 6518 [ # # ]:UBC 0 : elog(ERROR, "wrong tuple length");
6519 : :
368 noah@leadboat.com 6520 :CBC 63376 : dst = (char *) htup + htup->t_hoff;
6521 : 63376 : src = (char *) tuple->t_data + tuple->t_data->t_hoff;
6522 : :
6523 : : /* Like RecordTransactionCommit(), log only if needed */
6524 [ + + ]: 63376 : if (XLogStandbyInfoActive())
6525 : 49710 : nmsgs = inplaceGetInvalidationMessages(&invalMessages,
6526 : : &RelcacheInitFileInval);
6527 : :
6528 : : /*
6529 : : * Unlink relcache init files as needed. If unlinking, acquire
6530 : : * RelCacheInitLock until after associated invalidations. By doing this
6531 : : * in advance, if we checkpoint and then crash between inplace
6532 : : * XLogInsert() and inval, we don't rely on StartupXLOG() ->
6533 : : * RelationCacheInitFileRemove(). That uses elevel==LOG, so replay would
6534 : : * neglect to PANIC on EIO.
6535 : : */
6536 : 63376 : PreInplace_Inval();
6537 : :
6538 : : /*----------
6539 : : * NO EREPORT(ERROR) from here till changes are complete
6540 : : *
6541 : : * Our buffer lock won't stop a reader having already pinned and checked
6542 : : * visibility for this tuple. Hence, we write WAL first, then mutate the
6543 : : * buffer. Like in MarkBufferDirtyHint() or RecordTransactionCommit(),
6544 : : * checkpoint delay makes that acceptable. With the usual order of
6545 : : * changes, a crash after memcpy() and before XLogInsert() could allow
6546 : : * datfrozenxid to overtake relfrozenxid:
6547 : : *
6548 : : * ["D" is a VACUUM (ONLY_DATABASE_STATS)]
6549 : : * ["R" is a VACUUM tbl]
6550 : : * D: vac_update_datfrozenxid() -> systable_beginscan(pg_class)
6551 : : * D: systable_getnext() returns pg_class tuple of tbl
6552 : : * R: memcpy() into pg_class tuple of tbl
6553 : : * D: raise pg_database.datfrozenxid, XLogInsert(), finish
6554 : : * [crash]
6555 : : * [recovery restores datfrozenxid w/o relfrozenxid]
6556 : : *
6557 : : * Mimic MarkBufferDirtyHint() subroutine XLogSaveBufferForHint().
6558 : : * Specifically, use DELAY_CHKPT_START, and copy the buffer to the stack.
6559 : : * The stack copy facilitates a FPI of the post-mutation block before we
6560 : : * accept other sessions seeing it. DELAY_CHKPT_START allows us to
6561 : : * XLogInsert() before MarkBufferDirty(). Since XLogSaveBufferForHint()
6562 : : * can operate under BUFFER_LOCK_SHARED, it can't avoid DELAY_CHKPT_START.
6563 : : * This function, however, likely could avoid it with the following order
6564 : : * of operations: MarkBufferDirty(), XLogInsert(), memcpy(). Opt to use
6565 : : * DELAY_CHKPT_START here, too, as a way to have fewer distinct code
6566 : : * patterns to analyze. Inplace update isn't so frequent that it should
6567 : : * pursue the small optimization of skipping DELAY_CHKPT_START.
6568 : : */
6569 [ - + ]: 63376 : Assert((MyProc->delayChkptFlags & DELAY_CHKPT_START) == 0);
6570 : 63376 : START_CRIT_SECTION();
6571 : 63376 : MyProc->delayChkptFlags |= DELAY_CHKPT_START;
6572 : :
6573 : : /* XLOG stuff */
5433 rhaas@postgresql.org 6574 [ + - + + : 63376 : if (RelationNeedsWAL(relation))
+ - + + ]
6575 : : {
6576 : : xl_heap_inplace xlrec;
6577 : : PGAlignedBlock copied_buffer;
368 noah@leadboat.com 6578 : 63368 : char *origdata = (char *) BufferGetBlock(buffer);
6579 : 63368 : Page page = BufferGetPage(buffer);
6580 : 63368 : uint16 lower = ((PageHeader) page)->pd_lower;
6581 : 63368 : uint16 upper = ((PageHeader) page)->pd_upper;
6582 : : uintptr_t dst_offset_in_block;
6583 : : RelFileLocator rlocator;
6584 : : ForkNumber forkno;
6585 : : BlockNumber blkno;
6586 : : XLogRecPtr recptr;
6587 : :
3995 heikki.linnakangas@i 6588 : 63368 : xlrec.offnum = ItemPointerGetOffsetNumber(&tuple->t_self);
368 noah@leadboat.com 6589 : 63368 : xlrec.dbId = MyDatabaseId;
6590 : 63368 : xlrec.tsId = MyDatabaseTableSpace;
6591 : 63368 : xlrec.relcacheInitFileInval = RelcacheInitFileInval;
6592 : 63368 : xlrec.nmsgs = nmsgs;
6593 : :
3995 heikki.linnakangas@i 6594 : 63368 : XLogBeginInsert();
259 peter@eisentraut.org 6595 : 63368 : XLogRegisterData(&xlrec, MinSizeOfHeapInplace);
368 noah@leadboat.com 6596 [ + + ]: 63368 : if (nmsgs != 0)
259 peter@eisentraut.org 6597 : 35060 : XLogRegisterData(invalMessages,
6598 : : nmsgs * sizeof(SharedInvalidationMessage));
6599 : :
6600 : : /* register block matching what buffer will look like after changes */
368 noah@leadboat.com 6601 : 63368 : memcpy(copied_buffer.data, origdata, lower);
6602 : 63368 : memcpy(copied_buffer.data + upper, origdata + upper, BLCKSZ - upper);
6603 : 63368 : dst_offset_in_block = dst - origdata;
6604 : 63368 : memcpy(copied_buffer.data + dst_offset_in_block, src, newlen);
6605 : 63368 : BufferGetTag(buffer, &rlocator, &forkno, &blkno);
6606 [ - + ]: 63368 : Assert(forkno == MAIN_FORKNUM);
6607 : 63368 : XLogRegisterBlock(0, &rlocator, forkno, blkno, copied_buffer.data,
6608 : : REGBUF_STANDARD);
6609 : 63368 : XLogRegisterBufData(0, src, newlen);
6610 : :
6611 : : /* inplace updates aren't decoded atm, don't log the origin */
6612 : :
3995 heikki.linnakangas@i 6613 : 63368 : recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_INPLACE);
6614 : :
368 noah@leadboat.com 6615 : 63368 : PageSetLSN(page, recptr);
6616 : : }
6617 : :
6618 : 63376 : memcpy(dst, src, newlen);
6619 : :
6620 : 63376 : MarkBufferDirty(buffer);
6621 : :
6622 : 63376 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
6623 : :
6624 : : /*
6625 : : * Send invalidations to shared queue. SearchSysCacheLocked1() assumes we
6626 : : * do this before UnlockTuple().
6627 : : *
6628 : : * If we're mutating a tuple visible only to this transaction, there's an
6629 : : * equivalent transactional inval from the action that created the tuple,
6630 : : * and this inval is superfluous.
6631 : : */
6632 : 63376 : AtInplace_Inval();
6633 : :
6634 : 63376 : MyProc->delayChkptFlags &= ~DELAY_CHKPT_START;
7111 tgl@sss.pgh.pa.us 6635 [ - + ]: 63376 : END_CRIT_SECTION();
368 noah@leadboat.com 6636 : 63376 : UnlockTuple(relation, &tuple->t_self, InplaceUpdateTupleLock);
6637 : :
6638 : 63376 : AcceptInvalidationMessages(); /* local processing of just-sent inval */
6639 : :
6640 : : /*
6641 : : * Queue a transactional inval. The immediate invalidation we just sent
6642 : : * is the only one known to be necessary. To reduce risk from the
6643 : : * transition to immediate invalidation, continue sending a transactional
6644 : : * invalidation like we've long done. Third-party code might rely on it.
6645 : : */
7111 tgl@sss.pgh.pa.us 6646 [ + + ]: 63376 : if (!IsBootstrapProcessingMode())
5187 6647 : 48726 : CacheInvalidateHeapTuple(relation, tuple, NULL);
7111 6648 : 63376 : }
6649 : :
6650 : : /*
6651 : : * heap_inplace_unlock - reverse of heap_inplace_lock
6652 : : */
6653 : : void
399 noah@leadboat.com 6654 : 28215 : heap_inplace_unlock(Relation relation,
6655 : : HeapTuple oldtup, Buffer buffer)
6656 : : {
6657 : 28215 : LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
6658 : 28215 : UnlockTuple(relation, &oldtup->t_self, InplaceUpdateTupleLock);
360 6659 : 28215 : ForgetInplace_Inval();
399 6660 : 28215 : }
6661 : :
6662 : : #define FRM_NOOP 0x0001
6663 : : #define FRM_INVALIDATE_XMAX 0x0002
6664 : : #define FRM_RETURN_IS_XID 0x0004
6665 : : #define FRM_RETURN_IS_MULTI 0x0008
6666 : : #define FRM_MARK_COMMITTED 0x0010
6667 : :
6668 : : /*
6669 : : * FreezeMultiXactId
6670 : : * Determine what to do during freezing when a tuple is marked by a
6671 : : * MultiXactId.
6672 : : *
6673 : : * "flags" is an output value; it's used to tell caller what to do on return.
6674 : : * "pagefrz" is an input/output value, used to manage page level freezing.
6675 : : *
6676 : : * Possible values that we can set in "flags":
6677 : : * FRM_NOOP
6678 : : * don't do anything -- keep existing Xmax
6679 : : * FRM_INVALIDATE_XMAX
6680 : : * mark Xmax as InvalidTransactionId and set XMAX_INVALID flag.
6681 : : * FRM_RETURN_IS_XID
6682 : : * The Xid return value is a single update Xid to set as xmax.
6683 : : * FRM_MARK_COMMITTED
6684 : : * Xmax can be marked as HEAP_XMAX_COMMITTED
6685 : : * FRM_RETURN_IS_MULTI
6686 : : * The return value is a new MultiXactId to set as new Xmax.
6687 : : * (caller must obtain proper infomask bits using GetMultiXactIdHintBits)
6688 : : *
6689 : : * Caller delegates control of page freezing to us. In practice we always
6690 : : * force freezing of caller's page unless FRM_NOOP processing is indicated.
6691 : : * We help caller ensure that XIDs < FreezeLimit and MXIDs < MultiXactCutoff
6692 : : * can never be left behind. We freely choose when and how to process each
6693 : : * Multi, without ever violating the cutoff postconditions for freezing.
6694 : : *
6695 : : * It's useful to remove Multis on a proactive timeline (relative to freezing
6696 : : * XIDs) to keep MultiXact member SLRU buffer misses to a minimum. It can also
6697 : : * be cheaper in the short run, for us, since we too can avoid SLRU buffer
6698 : : * misses through eager processing.
6699 : : *
6700 : : * NB: Creates a _new_ MultiXactId when FRM_RETURN_IS_MULTI is set, though only
6701 : : * when FreezeLimit and/or MultiXactCutoff cutoffs leave us with no choice.
6702 : : * This can usually be put off, which is usually enough to avoid it altogether.
6703 : : * Allocating new multis during VACUUM should be avoided on general principle;
6704 : : * only VACUUM can advance relminmxid, so allocating new Multis here comes with
6705 : : * its own special risks.
6706 : : *
6707 : : * NB: Caller must maintain "no freeze" NewRelfrozenXid/NewRelminMxid trackers
6708 : : * using heap_tuple_should_freeze when we haven't forced page-level freezing.
6709 : : *
6710 : : * NB: Caller should avoid needlessly calling heap_tuple_should_freeze when we
6711 : : * have already forced page-level freezing, since that might incur the same
6712 : : * SLRU buffer misses that we specifically intended to avoid by freezing.
6713 : : */
6714 : : static TransactionId
4334 alvherre@alvh.no-ip. 6715 : 6 : FreezeMultiXactId(MultiXactId multi, uint16 t_infomask,
6716 : : const struct VacuumCutoffs *cutoffs, uint16 *flags,
6717 : : HeapPageFreeze *pagefrz)
6718 : : {
6719 : : TransactionId newxmax;
6720 : : MultiXactMember *members;
6721 : : int nmembers;
6722 : : bool need_replace;
6723 : : int nnewmembers;
6724 : : MultiXactMember *newmembers;
6725 : : bool has_lockers;
6726 : : TransactionId update_xid;
6727 : : bool update_committed;
6728 : : TransactionId FreezePageRelfrozenXid;
6729 : :
6730 : 6 : *flags = 0;
6731 : :
6732 : : /* We should only be called in Multis */
6733 [ - + ]: 6 : Assert(t_infomask & HEAP_XMAX_IS_MULTI);
6734 : :
3413 6735 [ + - - + ]: 12 : if (!MultiXactIdIsValid(multi) ||
6736 : 6 : HEAP_LOCKED_UPGRADED(t_infomask))
6737 : : {
4334 alvherre@alvh.no-ip. 6738 :UBC 0 : *flags |= FRM_INVALIDATE_XMAX;
1035 pg@bowt.ie 6739 : 0 : pagefrz->freeze_required = true;
4334 alvherre@alvh.no-ip. 6740 : 0 : return InvalidTransactionId;
6741 : : }
1041 pg@bowt.ie 6742 [ - + ]:CBC 6 : else if (MultiXactIdPrecedes(multi, cutoffs->relminmxid))
2906 andres@anarazel.de 6743 [ # # ]:UBC 0 : ereport(ERROR,
6744 : : (errcode(ERRCODE_DATA_CORRUPTED),
6745 : : errmsg_internal("found multixact %u from before relminmxid %u",
6746 : : multi, cutoffs->relminmxid)));
1035 pg@bowt.ie 6747 [ + + ]:CBC 6 : else if (MultiXactIdPrecedes(multi, cutoffs->OldestMxact))
6748 : : {
6749 : : TransactionId update_xact;
6750 : :
6751 : : /*
6752 : : * This old multi cannot possibly have members still running, but
6753 : : * verify just in case. If it was a locker only, it can be removed
6754 : : * without any further consideration; but if it contained an update,
6755 : : * we might need to preserve it.
6756 : : */
2906 andres@anarazel.de 6757 [ - + ]: 4 : if (MultiXactIdIsRunning(multi,
6758 : 4 : HEAP_XMAX_IS_LOCKED_ONLY(t_infomask)))
2906 andres@anarazel.de 6759 [ # # ]:UBC 0 : ereport(ERROR,
6760 : : (errcode(ERRCODE_DATA_CORRUPTED),
6761 : : errmsg_internal("multixact %u from before multi freeze cutoff %u found to be still running",
6762 : : multi, cutoffs->OldestMxact)));
6763 : :
4334 alvherre@alvh.no-ip. 6764 [ + - ]:CBC 4 : if (HEAP_XMAX_IS_LOCKED_ONLY(t_infomask))
6765 : : {
6766 : 4 : *flags |= FRM_INVALIDATE_XMAX;
1035 pg@bowt.ie 6767 : 4 : pagefrz->freeze_required = true;
6768 : 4 : return InvalidTransactionId;
6769 : : }
6770 : :
6771 : : /* replace multi with single XID for its updater? */
1035 pg@bowt.ie 6772 :UBC 0 : update_xact = MultiXactIdGetUpdateXid(multi, t_infomask);
6773 [ # # ]: 0 : if (TransactionIdPrecedes(update_xact, cutoffs->relfrozenxid))
6774 [ # # ]: 0 : ereport(ERROR,
6775 : : (errcode(ERRCODE_DATA_CORRUPTED),
6776 : : errmsg_internal("multixact %u contains update XID %u from before relfrozenxid %u",
6777 : : multi, update_xact,
6778 : : cutoffs->relfrozenxid)));
6779 [ # # ]: 0 : else if (TransactionIdPrecedes(update_xact, cutoffs->OldestXmin))
6780 : : {
6781 : : /*
6782 : : * Updater XID has to have aborted (otherwise the tuple would have
6783 : : * been pruned away instead, since updater XID is < OldestXmin).
6784 : : * Just remove xmax.
6785 : : */
1029 6786 [ # # ]: 0 : if (TransactionIdDidCommit(update_xact))
1035 6787 [ # # ]: 0 : ereport(ERROR,
6788 : : (errcode(ERRCODE_DATA_CORRUPTED),
6789 : : errmsg_internal("multixact %u contains committed update XID %u from before removable cutoff %u",
6790 : : multi, update_xact,
6791 : : cutoffs->OldestXmin)));
6792 : 0 : *flags |= FRM_INVALIDATE_XMAX;
6793 : 0 : pagefrz->freeze_required = true;
6794 : 0 : return InvalidTransactionId;
6795 : : }
6796 : :
6797 : : /* Have to keep updater XID as new xmax */
6798 : 0 : *flags |= FRM_RETURN_IS_XID;
6799 : 0 : pagefrz->freeze_required = true;
6800 : 0 : return update_xact;
6801 : : }
6802 : :
6803 : : /*
6804 : : * Some member(s) of this Multi may be below FreezeLimit xid cutoff, so we
6805 : : * need to walk the whole members array to figure out what to do, if
6806 : : * anything.
6807 : : */
6808 : : nmembers =
3413 alvherre@alvh.no-ip. 6809 :CBC 2 : GetMultiXactIdMembers(multi, &members, false,
4109 6810 : 2 : HEAP_XMAX_IS_LOCKED_ONLY(t_infomask));
4334 6811 [ - + ]: 2 : if (nmembers <= 0)
6812 : : {
6813 : : /* Nothing worth keeping */
4334 alvherre@alvh.no-ip. 6814 :UBC 0 : *flags |= FRM_INVALIDATE_XMAX;
1035 pg@bowt.ie 6815 : 0 : pagefrz->freeze_required = true;
4334 alvherre@alvh.no-ip. 6816 : 0 : return InvalidTransactionId;
6817 : : }
6818 : :
6819 : : /*
6820 : : * The FRM_NOOP case is the only case where we might need to ratchet back
6821 : : * FreezePageRelfrozenXid or FreezePageRelminMxid. It is also the only
6822 : : * case where our caller might ratchet back its NoFreezePageRelfrozenXid
6823 : : * or NoFreezePageRelminMxid "no freeze" trackers to deal with a multi.
6824 : : * FRM_NOOP handling should result in the NewRelfrozenXid/NewRelminMxid
6825 : : * trackers managed by VACUUM being ratcheting back by xmax to the degree
6826 : : * required to make it safe to leave xmax undisturbed, independent of
6827 : : * whether or not page freezing is triggered somewhere else.
6828 : : *
6829 : : * Our policy is to force freezing in every case other than FRM_NOOP,
6830 : : * which obviates the need to maintain either set of trackers, anywhere.
6831 : : * Every other case will reliably execute a freeze plan for xmax that
6832 : : * either replaces xmax with an XID/MXID >= OldestXmin/OldestMxact, or
6833 : : * sets xmax to an InvalidTransactionId XID, rendering xmax fully frozen.
6834 : : * (VACUUM's NewRelfrozenXid/NewRelminMxid trackers are initialized with
6835 : : * OldestXmin/OldestMxact, so later values never need to be tracked here.)
6836 : : */
4334 alvherre@alvh.no-ip. 6837 :CBC 2 : need_replace = false;
1035 pg@bowt.ie 6838 : 2 : FreezePageRelfrozenXid = pagefrz->FreezePageRelfrozenXid;
1041 6839 [ + + ]: 4 : for (int i = 0; i < nmembers; i++)
6840 : : {
6841 : 3 : TransactionId xid = members[i].xid;
6842 : :
6843 [ - + ]: 3 : Assert(!TransactionIdPrecedes(xid, cutoffs->relfrozenxid));
6844 : :
6845 [ + + ]: 3 : if (TransactionIdPrecedes(xid, cutoffs->FreezeLimit))
6846 : : {
6847 : : /* Can't violate the FreezeLimit postcondition */
4334 alvherre@alvh.no-ip. 6848 : 1 : need_replace = true;
6849 : 1 : break;
6850 : : }
1035 pg@bowt.ie 6851 [ - + ]: 2 : if (TransactionIdPrecedes(xid, FreezePageRelfrozenXid))
1035 pg@bowt.ie 6852 :UBC 0 : FreezePageRelfrozenXid = xid;
6853 : : }
6854 : :
6855 : : /* Can't violate the MultiXactCutoff postcondition, either */
1035 pg@bowt.ie 6856 [ + + ]:CBC 2 : if (!need_replace)
6857 : 1 : need_replace = MultiXactIdPrecedes(multi, cutoffs->MultiXactCutoff);
6858 : :
4334 alvherre@alvh.no-ip. 6859 [ + + ]: 2 : if (!need_replace)
6860 : : {
6861 : : /*
6862 : : * vacuumlazy.c might ratchet back NewRelminMxid, NewRelfrozenXid, or
6863 : : * both together to make it safe to retain this particular multi after
6864 : : * freezing its page
6865 : : */
6866 : 1 : *flags |= FRM_NOOP;
1035 pg@bowt.ie 6867 : 1 : pagefrz->FreezePageRelfrozenXid = FreezePageRelfrozenXid;
6868 [ - + ]: 1 : if (MultiXactIdPrecedes(multi, pagefrz->FreezePageRelminMxid))
1035 pg@bowt.ie 6869 :UBC 0 : pagefrz->FreezePageRelminMxid = multi;
4334 alvherre@alvh.no-ip. 6870 :CBC 1 : pfree(members);
1304 pg@bowt.ie 6871 : 1 : return multi;
6872 : : }
6873 : :
6874 : : /*
6875 : : * Do a more thorough second pass over the multi to figure out which
6876 : : * member XIDs actually need to be kept. Checking the precise status of
6877 : : * individual members might even show that we don't need to keep anything.
6878 : : * That is quite possible even though the Multi must be >= OldestMxact,
6879 : : * since our second pass only keeps member XIDs when it's truly necessary;
6880 : : * even member XIDs >= OldestXmin often won't be kept by second pass.
6881 : : */
4334 alvherre@alvh.no-ip. 6882 : 1 : nnewmembers = 0;
6883 : 1 : newmembers = palloc(sizeof(MultiXactMember) * nmembers);
6884 : 1 : has_lockers = false;
6885 : 1 : update_xid = InvalidTransactionId;
6886 : 1 : update_committed = false;
6887 : :
6888 : : /*
6889 : : * Determine whether to keep each member xid, or to ignore it instead
6890 : : */
1041 pg@bowt.ie 6891 [ + + ]: 3 : for (int i = 0; i < nmembers; i++)
6892 : : {
6893 : 2 : TransactionId xid = members[i].xid;
6894 : 2 : MultiXactStatus mstatus = members[i].status;
6895 : :
6896 [ - + ]: 2 : Assert(!TransactionIdPrecedes(xid, cutoffs->relfrozenxid));
6897 : :
6898 [ + - ]: 2 : if (!ISUPDATE_from_mxstatus(mstatus))
6899 : : {
6900 : : /*
6901 : : * Locker XID (not updater XID). We only keep lockers that are
6902 : : * still running.
6903 : : */
6904 [ + - + + ]: 4 : if (TransactionIdIsCurrentTransactionId(xid) ||
6905 : 2 : TransactionIdIsInProgress(xid))
6906 : : {
1035 6907 [ - + ]: 1 : if (TransactionIdPrecedes(xid, cutoffs->OldestXmin))
1035 pg@bowt.ie 6908 [ # # ]:UBC 0 : ereport(ERROR,
6909 : : (errcode(ERRCODE_DATA_CORRUPTED),
6910 : : errmsg_internal("multixact %u contains running locker XID %u from before removable cutoff %u",
6911 : : multi, xid,
6912 : : cutoffs->OldestXmin)));
1041 pg@bowt.ie 6913 :CBC 1 : newmembers[nnewmembers++] = members[i];
6914 : 1 : has_lockers = true;
6915 : : }
6916 : :
6917 : 2 : continue;
6918 : : }
6919 : :
6920 : : /*
6921 : : * Updater XID (not locker XID). Should we keep it?
6922 : : *
6923 : : * Since the tuple wasn't totally removed when vacuum pruned, the
6924 : : * update Xid cannot possibly be older than OldestXmin cutoff unless
6925 : : * the updater XID aborted. If the updater transaction is known
6926 : : * aborted or crashed then it's okay to ignore it, otherwise not.
6927 : : *
6928 : : * In any case the Multi should never contain two updaters, whatever
6929 : : * their individual commit status. Check for that first, in passing.
6930 : : */
1041 pg@bowt.ie 6931 [ # # ]:UBC 0 : if (TransactionIdIsValid(update_xid))
6932 [ # # ]: 0 : ereport(ERROR,
6933 : : (errcode(ERRCODE_DATA_CORRUPTED),
6934 : : errmsg_internal("multixact %u has two or more updating members",
6935 : : multi),
6936 : : errdetail_internal("First updater XID=%u second updater XID=%u.",
6937 : : update_xid, xid)));
6938 : :
6939 : : /*
6940 : : * As with all tuple visibility routines, it's critical to test
6941 : : * TransactionIdIsInProgress before TransactionIdDidCommit, because of
6942 : : * race conditions explained in detail in heapam_visibility.c.
6943 : : */
6944 [ # # # # ]: 0 : if (TransactionIdIsCurrentTransactionId(xid) ||
6945 : 0 : TransactionIdIsInProgress(xid))
6946 : 0 : update_xid = xid;
6947 [ # # ]: 0 : else if (TransactionIdDidCommit(xid))
6948 : : {
6949 : : /*
6950 : : * The transaction committed, so we can tell caller to set
6951 : : * HEAP_XMAX_COMMITTED. (We can only do this because we know the
6952 : : * transaction is not running.)
6953 : : */
6954 : 0 : update_committed = true;
6955 : 0 : update_xid = xid;
6956 : : }
6957 : : else
6958 : : {
6959 : : /*
6960 : : * Not in progress, not committed -- must be aborted or crashed;
6961 : : * we can ignore it.
6962 : : */
6963 : 0 : continue;
6964 : : }
6965 : :
6966 : : /*
6967 : : * We determined that updater must be kept -- add it to pending new
6968 : : * members list
6969 : : */
1035 6970 [ # # ]: 0 : if (TransactionIdPrecedes(xid, cutoffs->OldestXmin))
6971 [ # # ]: 0 : ereport(ERROR,
6972 : : (errcode(ERRCODE_DATA_CORRUPTED),
6973 : : errmsg_internal("multixact %u contains committed update XID %u from before removable cutoff %u",
6974 : : multi, xid, cutoffs->OldestXmin)));
1041 6975 : 0 : newmembers[nnewmembers++] = members[i];
6976 : : }
6977 : :
4334 alvherre@alvh.no-ip. 6978 :CBC 1 : pfree(members);
6979 : :
6980 : : /*
6981 : : * Determine what to do with caller's multi based on information gathered
6982 : : * during our second pass
6983 : : */
6984 [ - + ]: 1 : if (nnewmembers == 0)
6985 : : {
6986 : : /* Nothing worth keeping */
4334 alvherre@alvh.no-ip. 6987 :UBC 0 : *flags |= FRM_INVALIDATE_XMAX;
1041 pg@bowt.ie 6988 : 0 : newxmax = InvalidTransactionId;
6989 : : }
4334 alvherre@alvh.no-ip. 6990 [ - + - - ]:CBC 1 : else if (TransactionIdIsValid(update_xid) && !has_lockers)
6991 : : {
6992 : : /*
6993 : : * If there's a single member and it's an update, pass it back alone
6994 : : * without creating a new Multi. (XXX we could do this when there's a
6995 : : * single remaining locker, too, but that would complicate the API too
6996 : : * much; moreover, the case with the single updater is more
6997 : : * interesting, because those are longer-lived.)
6998 : : */
4334 alvherre@alvh.no-ip. 6999 [ # # ]:UBC 0 : Assert(nnewmembers == 1);
7000 : 0 : *flags |= FRM_RETURN_IS_XID;
7001 [ # # ]: 0 : if (update_committed)
7002 : 0 : *flags |= FRM_MARK_COMMITTED;
1041 pg@bowt.ie 7003 : 0 : newxmax = update_xid;
7004 : : }
7005 : : else
7006 : : {
7007 : : /*
7008 : : * Create a new multixact with the surviving members of the previous
7009 : : * one, to set as new Xmax in the tuple
7010 : : */
1041 pg@bowt.ie 7011 :CBC 1 : newxmax = MultiXactIdCreateFromMembers(nnewmembers, newmembers);
4334 alvherre@alvh.no-ip. 7012 : 1 : *flags |= FRM_RETURN_IS_MULTI;
7013 : : }
7014 : :
7015 : 1 : pfree(newmembers);
7016 : :
1035 pg@bowt.ie 7017 : 1 : pagefrz->freeze_required = true;
1041 7018 : 1 : return newxmax;
7019 : : }
7020 : :
7021 : : /*
7022 : : * heap_prepare_freeze_tuple
7023 : : *
7024 : : * Check to see whether any of the XID fields of a tuple (xmin, xmax, xvac)
7025 : : * are older than the OldestXmin and/or OldestMxact freeze cutoffs. If so,
7026 : : * setup enough state (in the *frz output argument) to enable caller to
7027 : : * process this tuple as part of freezing its page, and return true. Return
7028 : : * false if nothing can be changed about the tuple right now.
7029 : : *
7030 : : * Also sets *totally_frozen to true if the tuple will be totally frozen once
7031 : : * caller executes returned freeze plan (or if the tuple was already totally
7032 : : * frozen by an earlier VACUUM). This indicates that there are no remaining
7033 : : * XIDs or MultiXactIds that will need to be processed by a future VACUUM.
7034 : : *
7035 : : * VACUUM caller must assemble HeapTupleFreeze freeze plan entries for every
7036 : : * tuple that we returned true for, and then execute freezing. Caller must
7037 : : * initialize pagefrz fields for page as a whole before first call here for
7038 : : * each heap page.
7039 : : *
7040 : : * VACUUM caller decides on whether or not to freeze the page as a whole.
7041 : : * We'll often prepare freeze plans for a page that caller just discards.
7042 : : * However, VACUUM doesn't always get to make a choice; it must freeze when
7043 : : * pagefrz.freeze_required is set, to ensure that any XIDs < FreezeLimit (and
7044 : : * MXIDs < MultiXactCutoff) can never be left behind. We help to make sure
7045 : : * that VACUUM always follows that rule.
7046 : : *
7047 : : * We sometimes force freezing of xmax MultiXactId values long before it is
7048 : : * strictly necessary to do so just to ensure the FreezeLimit postcondition.
7049 : : * It's worth processing MultiXactIds proactively when it is cheap to do so,
7050 : : * and it's convenient to make that happen by piggy-backing it on the "force
7051 : : * freezing" mechanism. Conversely, we sometimes delay freezing MultiXactIds
7052 : : * because it is expensive right now (though only when it's still possible to
7053 : : * do so without violating the FreezeLimit/MultiXactCutoff postcondition).
7054 : : *
7055 : : * It is assumed that the caller has checked the tuple with
7056 : : * HeapTupleSatisfiesVacuum() and determined that it is not HEAPTUPLE_DEAD
7057 : : * (else we should be removing the tuple, not freezing it).
7058 : : *
7059 : : * NB: This function has side effects: it might allocate a new MultiXactId.
7060 : : * It will be set as tuple's new xmax when our *frz output is processed within
7061 : : * heap_execute_freeze_tuple later on. If the tuple is in a shared buffer
7062 : : * then caller had better have an exclusive lock on it already.
7063 : : */
7064 : : bool
2906 andres@anarazel.de 7065 : 4491892 : heap_prepare_freeze_tuple(HeapTupleHeader tuple,
7066 : : const struct VacuumCutoffs *cutoffs,
7067 : : HeapPageFreeze *pagefrz,
7068 : : HeapTupleFreeze *frz, bool *totally_frozen)
7069 : : {
1041 pg@bowt.ie 7070 : 4491892 : bool xmin_already_frozen = false,
7071 : 4491892 : xmax_already_frozen = false;
7072 : 4491892 : bool freeze_xmin = false,
7073 : 4491892 : replace_xvac = false,
7074 : 4491892 : replace_xmax = false,
7075 : 4491892 : freeze_xmax = false;
7076 : : TransactionId xid;
7077 : :
1029 7078 : 4491892 : frz->xmax = HeapTupleHeaderGetRawXmax(tuple);
4334 alvherre@alvh.no-ip. 7079 : 4491892 : frz->t_infomask2 = tuple->t_infomask2;
7080 : 4491892 : frz->t_infomask = tuple->t_infomask;
1029 pg@bowt.ie 7081 : 4491892 : frz->frzflags = 0;
7082 : 4491892 : frz->checkflags = 0;
7083 : :
7084 : : /*
7085 : : * Process xmin, while keeping track of whether it's already frozen, or
7086 : : * will become frozen iff our freeze plan is executed by caller (could be
7087 : : * neither).
7088 : : */
6932 tgl@sss.pgh.pa.us 7089 : 4491892 : xid = HeapTupleHeaderGetXmin(tuple);
2371 alvherre@alvh.no-ip. 7090 [ + + ]: 4491892 : if (!TransactionIdIsNormal(xid))
1041 pg@bowt.ie 7091 : 1335025 : xmin_already_frozen = true;
7092 : : else
7093 : : {
7094 [ - + ]: 3156867 : if (TransactionIdPrecedes(xid, cutoffs->relfrozenxid))
2906 andres@anarazel.de 7095 [ # # ]:UBC 0 : ereport(ERROR,
7096 : : (errcode(ERRCODE_DATA_CORRUPTED),
7097 : : errmsg_internal("found xmin %u from before relfrozenxid %u",
7098 : : xid, cutoffs->relfrozenxid)));
7099 : :
7100 : : /* Will set freeze_xmin flags in freeze plan below */
1035 pg@bowt.ie 7101 :CBC 3156867 : freeze_xmin = TransactionIdPrecedes(xid, cutoffs->OldestXmin);
7102 : :
7103 : : /* Verify that xmin committed if and when freeze plan is executed */
1029 7104 [ + + ]: 3156867 : if (freeze_xmin)
7105 : 2557379 : frz->checkflags |= HEAP_FREEZE_CHECK_XMIN_COMMITTED;
7106 : : }
7107 : :
7108 : : /*
7109 : : * Old-style VACUUM FULL is gone, but we have to process xvac for as long
7110 : : * as we support having MOVED_OFF/MOVED_IN tuples in the database
7111 : : */
1041 7112 : 4491892 : xid = HeapTupleHeaderGetXvac(tuple);
7113 [ - + ]: 4491892 : if (TransactionIdIsNormal(xid))
7114 : : {
1041 pg@bowt.ie 7115 [ # # ]:UBC 0 : Assert(TransactionIdPrecedesOrEquals(cutoffs->relfrozenxid, xid));
7116 [ # # ]: 0 : Assert(TransactionIdPrecedes(xid, cutoffs->OldestXmin));
7117 : :
7118 : : /*
7119 : : * For Xvac, we always freeze proactively. This allows totally_frozen
7120 : : * tracking to ignore xvac.
7121 : : */
1035 7122 : 0 : replace_xvac = pagefrz->freeze_required = true;
7123 : :
7124 : : /* Will set replace_xvac flags in freeze plan below */
7125 : : }
7126 : :
7127 : : /* Now process xmax */
1029 pg@bowt.ie 7128 :CBC 4491892 : xid = frz->xmax;
4352 alvherre@alvh.no-ip. 7129 [ + + ]: 4491892 : if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
7130 : : {
7131 : : /* Raw xmax is a MultiXactId */
7132 : : TransactionId newxmax;
7133 : : uint16 flags;
7134 : :
7135 : : /*
7136 : : * We will either remove xmax completely (in the "freeze_xmax" path),
7137 : : * process xmax by replacing it (in the "replace_xmax" path), or
7138 : : * perform no-op xmax processing. The only constraint is that the
7139 : : * FreezeLimit/MultiXactCutoff postcondition must never be violated.
7140 : : */
1041 pg@bowt.ie 7141 : 6 : newxmax = FreezeMultiXactId(xid, tuple->t_infomask, cutoffs,
7142 : : &flags, pagefrz);
7143 : :
1035 7144 [ + + ]: 6 : if (flags & FRM_NOOP)
7145 : : {
7146 : : /*
7147 : : * xmax is a MultiXactId, and nothing about it changes for now.
7148 : : * This is the only case where 'freeze_required' won't have been
7149 : : * set for us by FreezeMultiXactId, as well as the only case where
7150 : : * neither freeze_xmax nor replace_xmax are set (given a multi).
7151 : : *
7152 : : * This is a no-op, but the call to FreezeMultiXactId might have
7153 : : * ratcheted back NewRelfrozenXid and/or NewRelminMxid trackers
7154 : : * for us (the "freeze page" variants, specifically). That'll
7155 : : * make it safe for our caller to freeze the page later on, while
7156 : : * leaving this particular xmax undisturbed.
7157 : : *
7158 : : * FreezeMultiXactId is _not_ responsible for the "no freeze"
7159 : : * NewRelfrozenXid/NewRelminMxid trackers, though -- that's our
7160 : : * job. A call to heap_tuple_should_freeze for this same tuple
7161 : : * will take place below if 'freeze_required' isn't set already.
7162 : : * (This repeats work from FreezeMultiXactId, but allows "no
7163 : : * freeze" tracker maintenance to happen in only one place.)
7164 : : */
7165 [ - + ]: 1 : Assert(!MultiXactIdPrecedes(newxmax, cutoffs->MultiXactCutoff));
7166 [ + - - + ]: 1 : Assert(MultiXactIdIsValid(newxmax) && xid == newxmax);
7167 : : }
7168 [ - + ]: 5 : else if (flags & FRM_RETURN_IS_XID)
7169 : : {
7170 : : /*
7171 : : * xmax will become an updater Xid (original MultiXact's updater
7172 : : * member Xid will be carried forward as a simple Xid in Xmax).
7173 : : */
1041 pg@bowt.ie 7174 [ # # ]:UBC 0 : Assert(!TransactionIdPrecedes(newxmax, cutoffs->OldestXmin));
7175 : :
7176 : : /*
7177 : : * NB -- some of these transformations are only valid because we
7178 : : * know the return Xid is a tuple updater (i.e. not merely a
7179 : : * locker.) Also note that the only reason we don't explicitly
7180 : : * worry about HEAP_KEYS_UPDATED is because it lives in
7181 : : * t_infomask2 rather than t_infomask.
7182 : : */
4334 alvherre@alvh.no-ip. 7183 : 0 : frz->t_infomask &= ~HEAP_XMAX_BITS;
7184 : 0 : frz->xmax = newxmax;
7185 [ # # ]: 0 : if (flags & FRM_MARK_COMMITTED)
3036 teodor@sigaev.ru 7186 : 0 : frz->t_infomask |= HEAP_XMAX_COMMITTED;
1041 pg@bowt.ie 7187 : 0 : replace_xmax = true;
7188 : : }
4334 alvherre@alvh.no-ip. 7189 [ + + ]:CBC 5 : else if (flags & FRM_RETURN_IS_MULTI)
7190 : : {
7191 : : uint16 newbits;
7192 : : uint16 newbits2;
7193 : :
7194 : : /*
7195 : : * xmax is an old MultiXactId that we have to replace with a new
7196 : : * MultiXactId, to carry forward two or more original member XIDs.
7197 : : */
1041 pg@bowt.ie 7198 [ - + ]: 1 : Assert(!MultiXactIdPrecedes(newxmax, cutoffs->OldestMxact));
7199 : :
7200 : : /*
7201 : : * We can't use GetMultiXactIdHintBits directly on the new multi
7202 : : * here; that routine initializes the masks to all zeroes, which
7203 : : * would lose other bits we need. Doing it this way ensures all
7204 : : * unrelated bits remain untouched.
7205 : : */
4334 alvherre@alvh.no-ip. 7206 : 1 : frz->t_infomask &= ~HEAP_XMAX_BITS;
7207 : 1 : frz->t_infomask2 &= ~HEAP_KEYS_UPDATED;
7208 : 1 : GetMultiXactIdHintBits(newxmax, &newbits, &newbits2);
7209 : 1 : frz->t_infomask |= newbits;
7210 : 1 : frz->t_infomask2 |= newbits2;
7211 : 1 : frz->xmax = newxmax;
1041 pg@bowt.ie 7212 : 1 : replace_xmax = true;
7213 : : }
7214 : : else
7215 : : {
7216 : : /*
7217 : : * Freeze plan for tuple "freezes xmax" in the strictest sense:
7218 : : * it'll leave nothing in xmax (neither an Xid nor a MultiXactId).
7219 : : */
7220 [ - + ]: 4 : Assert(flags & FRM_INVALIDATE_XMAX);
1304 7221 [ - + ]: 4 : Assert(!TransactionIdIsValid(newxmax));
7222 : :
7223 : : /* Will set freeze_xmax flags in freeze plan below */
1041 7224 : 4 : freeze_xmax = true;
7225 : : }
7226 : :
7227 : : /* MultiXactId processing forces freezing (barring FRM_NOOP case) */
1035 7228 [ - + - - : 6 : Assert(pagefrz->freeze_required || (!freeze_xmax && !replace_xmax));
- - ]
7229 : : }
3422 rhaas@postgresql.org 7230 [ + + ]: 4491886 : else if (TransactionIdIsNormal(xid))
7231 : : {
7232 : : /* Raw xmax is normal XID */
1041 pg@bowt.ie 7233 [ - + ]: 271150 : if (TransactionIdPrecedes(xid, cutoffs->relfrozenxid))
2906 andres@anarazel.de 7234 [ # # ]:UBC 0 : ereport(ERROR,
7235 : : (errcode(ERRCODE_DATA_CORRUPTED),
7236 : : errmsg_internal("found xmax %u from before relfrozenxid %u",
7237 : : xid, cutoffs->relfrozenxid)));
7238 : :
7239 : : /* Will set freeze_xmax flags in freeze plan below */
1029 pg@bowt.ie 7240 :CBC 271150 : freeze_xmax = TransactionIdPrecedes(xid, cutoffs->OldestXmin);
7241 : :
7242 : : /*
7243 : : * Verify that xmax aborted if and when freeze plan is executed,
7244 : : * provided it's from an update. (A lock-only xmax can be removed
7245 : : * independent of this, since the lock is released at xact end.)
7246 : : */
7247 [ + + + + ]: 271150 : if (freeze_xmax && !HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
7248 : 1649 : frz->checkflags |= HEAP_FREEZE_CHECK_XMAX_ABORTED;
7249 : : }
1070 7250 [ + - ]: 4220736 : else if (!TransactionIdIsValid(xid))
7251 : : {
7252 : : /* Raw xmax is InvalidTransactionId XID */
7253 [ - + ]: 4220736 : Assert((tuple->t_infomask & HEAP_XMAX_IS_MULTI) == 0);
2734 alvherre@alvh.no-ip. 7254 : 4220736 : xmax_already_frozen = true;
7255 : : }
7256 : : else
2734 alvherre@alvh.no-ip. 7257 [ # # ]:UBC 0 : ereport(ERROR,
7258 : : (errcode(ERRCODE_DATA_CORRUPTED),
7259 : : errmsg_internal("found raw xmax %u (infomask 0x%04x) not invalid and not multi",
7260 : : xid, tuple->t_infomask)));
7261 : :
1041 pg@bowt.ie 7262 [ + + ]:CBC 4491892 : if (freeze_xmin)
7263 : : {
7264 [ - + ]: 2557379 : Assert(!xmin_already_frozen);
7265 : :
7266 : 2557379 : frz->t_infomask |= HEAP_XMIN_FROZEN;
7267 : : }
7268 [ - + ]: 4491892 : if (replace_xvac)
7269 : : {
7270 : : /*
7271 : : * If a MOVED_OFF tuple is not dead, the xvac transaction must have
7272 : : * failed; whereas a non-dead MOVED_IN tuple must mean the xvac
7273 : : * transaction succeeded.
7274 : : */
1035 pg@bowt.ie 7275 [ # # ]:UBC 0 : Assert(pagefrz->freeze_required);
1041 7276 [ # # ]: 0 : if (tuple->t_infomask & HEAP_MOVED_OFF)
7277 : 0 : frz->frzflags |= XLH_INVALID_XVAC;
7278 : : else
7279 : 0 : frz->frzflags |= XLH_FREEZE_XVAC;
7280 : : }
1041 pg@bowt.ie 7281 [ + + ]:CBC 4491892 : if (replace_xmax)
7282 : : {
7283 [ + - - + ]: 1 : Assert(!xmax_already_frozen && !freeze_xmax);
1035 7284 [ - + ]: 1 : Assert(pagefrz->freeze_required);
7285 : :
7286 : : /* Already set replace_xmax flags in freeze plan earlier */
7287 : : }
4352 alvherre@alvh.no-ip. 7288 [ + + ]: 4491892 : if (freeze_xmax)
7289 : : {
1041 pg@bowt.ie 7290 [ + - - + ]: 2621 : Assert(!xmax_already_frozen && !replace_xmax);
7291 : :
4334 alvherre@alvh.no-ip. 7292 : 2621 : frz->xmax = InvalidTransactionId;
7293 : :
7294 : : /*
7295 : : * The tuple might be marked either XMAX_INVALID or XMAX_COMMITTED +
7296 : : * LOCKED. Normalize to INVALID just to be sure no one gets confused.
7297 : : * Also get rid of the HEAP_KEYS_UPDATED bit.
7298 : : */
7299 : 2621 : frz->t_infomask &= ~HEAP_XMAX_BITS;
7300 : 2621 : frz->t_infomask |= HEAP_XMAX_INVALID;
7301 : 2621 : frz->t_infomask2 &= ~HEAP_HOT_UPDATED;
7302 : 2621 : frz->t_infomask2 &= ~HEAP_KEYS_UPDATED;
7303 : : }
7304 : :
7305 : : /*
7306 : : * Determine if this tuple is already totally frozen, or will become
7307 : : * totally frozen (provided caller executes freeze plans for the page)
7308 : : */
1041 pg@bowt.ie 7309 [ + + + + : 8381675 : *totally_frozen = ((freeze_xmin || xmin_already_frozen) &&
+ + ]
7310 [ + + ]: 3889783 : (freeze_xmax || xmax_already_frozen));
7311 : :
1035 7312 [ + + + + : 4491892 : if (!pagefrz->freeze_required && !(xmin_already_frozen &&
+ + ]
7313 : : xmax_already_frozen))
7314 : : {
7315 : : /*
7316 : : * So far no previous tuple from the page made freezing mandatory.
7317 : : * Does this tuple force caller to freeze the entire page?
7318 : : */
7319 : 2032110 : pagefrz->freeze_required =
7320 : 2032110 : heap_tuple_should_freeze(tuple, cutoffs,
7321 : : &pagefrz->NoFreezePageRelfrozenXid,
7322 : : &pagefrz->NoFreezePageRelminMxid);
7323 : : }
7324 : :
7325 : : /* Tell caller if this tuple has a usable freeze plan set in *frz */
1041 7326 [ + + + - : 4491892 : return freeze_xmin || replace_xvac || replace_xmax || freeze_xmax;
+ - + + ]
7327 : : }
7328 : :
7329 : : /*
7330 : : * Perform xmin/xmax XID status sanity checks before actually executing freeze
7331 : : * plans.
7332 : : *
7333 : : * heap_prepare_freeze_tuple doesn't perform these checks directly because
7334 : : * pg_xact lookups are relatively expensive. They shouldn't be repeated by
7335 : : * successive VACUUMs that each decide against freezing the same page.
7336 : : */
7337 : : void
573 heikki.linnakangas@i 7338 : 20951 : heap_pre_freeze_checks(Buffer buffer,
7339 : : HeapTupleFreeze *tuples, int ntuples)
7340 : : {
1078 pg@bowt.ie 7341 : 20951 : Page page = BufferGetPage(buffer);
7342 : :
1029 7343 [ + + ]: 943167 : for (int i = 0; i < ntuples; i++)
7344 : : {
7345 : 922216 : HeapTupleFreeze *frz = tuples + i;
7346 : 922216 : ItemId itemid = PageGetItemId(page, frz->offset);
7347 : : HeapTupleHeader htup;
7348 : :
7349 : 922216 : htup = (HeapTupleHeader) PageGetItem(page, itemid);
7350 : :
7351 : : /* Deliberately avoid relying on tuple hint bits here */
7352 [ + + ]: 922216 : if (frz->checkflags & HEAP_FREEZE_CHECK_XMIN_COMMITTED)
7353 : : {
7354 : 922215 : TransactionId xmin = HeapTupleHeaderGetRawXmin(htup);
7355 : :
7356 [ - + ]: 922215 : Assert(!HeapTupleHeaderXminFrozen(htup));
7357 [ - + ]: 922215 : if (unlikely(!TransactionIdDidCommit(xmin)))
1029 pg@bowt.ie 7358 [ # # ]:UBC 0 : ereport(ERROR,
7359 : : (errcode(ERRCODE_DATA_CORRUPTED),
7360 : : errmsg_internal("uncommitted xmin %u needs to be frozen",
7361 : : xmin)));
7362 : : }
7363 : :
7364 : : /*
7365 : : * TransactionIdDidAbort won't work reliably in the presence of XIDs
7366 : : * left behind by transactions that were in progress during a crash,
7367 : : * so we can only check that xmax didn't commit
7368 : : */
1029 pg@bowt.ie 7369 [ + + ]:CBC 922216 : if (frz->checkflags & HEAP_FREEZE_CHECK_XMAX_ABORTED)
7370 : : {
7371 : 610 : TransactionId xmax = HeapTupleHeaderGetRawXmax(htup);
7372 : :
7373 [ - + ]: 610 : Assert(TransactionIdIsNormal(xmax));
7374 [ - + ]: 610 : if (unlikely(TransactionIdDidCommit(xmax)))
1029 pg@bowt.ie 7375 [ # # ]:UBC 0 : ereport(ERROR,
7376 : : (errcode(ERRCODE_DATA_CORRUPTED),
7377 : : errmsg_internal("cannot freeze committed xmax %u",
7378 : : xmax)));
7379 : : }
7380 : : }
573 heikki.linnakangas@i 7381 :CBC 20951 : }
7382 : :
7383 : : /*
7384 : : * Helper which executes freezing of one or more heap tuples on a page on
7385 : : * behalf of caller. Caller passes an array of tuple plans from
7386 : : * heap_prepare_freeze_tuple. Caller must set 'offset' in each plan for us.
7387 : : * Must be called in a critical section that also marks the buffer dirty and,
7388 : : * if needed, emits WAL.
7389 : : */
7390 : : void
7391 : 20951 : heap_freeze_prepared_tuples(Buffer buffer, HeapTupleFreeze *tuples, int ntuples)
7392 : : {
7393 : 20951 : Page page = BufferGetPage(buffer);
7394 : :
1078 pg@bowt.ie 7395 [ + + ]: 943167 : for (int i = 0; i < ntuples; i++)
7396 : : {
1029 7397 : 922216 : HeapTupleFreeze *frz = tuples + i;
7398 : 922216 : ItemId itemid = PageGetItemId(page, frz->offset);
7399 : : HeapTupleHeader htup;
7400 : :
1078 7401 : 922216 : htup = (HeapTupleHeader) PageGetItem(page, itemid);
1029 7402 : 922216 : heap_execute_freeze_tuple(htup, frz);
7403 : : }
1078 7404 : 20951 : }
7405 : :
7406 : : /*
7407 : : * heap_freeze_tuple
7408 : : * Freeze tuple in place, without WAL logging.
7409 : : *
7410 : : * Useful for callers like CLUSTER that perform their own WAL logging.
7411 : : */
7412 : : bool
2906 andres@anarazel.de 7413 : 364303 : heap_freeze_tuple(HeapTupleHeader tuple,
7414 : : TransactionId relfrozenxid, TransactionId relminmxid,
7415 : : TransactionId FreezeLimit, TransactionId MultiXactCutoff)
7416 : : {
7417 : : HeapTupleFreeze frz;
7418 : : bool do_freeze;
7419 : : bool totally_frozen;
7420 : : struct VacuumCutoffs cutoffs;
7421 : : HeapPageFreeze pagefrz;
7422 : :
1041 pg@bowt.ie 7423 : 364303 : cutoffs.relfrozenxid = relfrozenxid;
7424 : 364303 : cutoffs.relminmxid = relminmxid;
7425 : 364303 : cutoffs.OldestXmin = FreezeLimit;
7426 : 364303 : cutoffs.OldestMxact = MultiXactCutoff;
7427 : 364303 : cutoffs.FreezeLimit = FreezeLimit;
7428 : 364303 : cutoffs.MultiXactCutoff = MultiXactCutoff;
7429 : :
1035 7430 : 364303 : pagefrz.freeze_required = true;
7431 : 364303 : pagefrz.FreezePageRelfrozenXid = FreezeLimit;
7432 : 364303 : pagefrz.FreezePageRelminMxid = MultiXactCutoff;
7433 : 364303 : pagefrz.NoFreezePageRelfrozenXid = FreezeLimit;
7434 : 364303 : pagefrz.NoFreezePageRelminMxid = MultiXactCutoff;
7435 : :
1041 7436 : 364303 : do_freeze = heap_prepare_freeze_tuple(tuple, &cutoffs,
7437 : : &pagefrz, &frz, &totally_frozen);
7438 : :
7439 : : /*
7440 : : * Note that because this is not a WAL-logged operation, we don't need to
7441 : : * fill in the offset in the freeze record.
7442 : : */
7443 : :
4334 alvherre@alvh.no-ip. 7444 [ + + ]: 364303 : if (do_freeze)
7445 : 262821 : heap_execute_freeze_tuple(tuple, &frz);
7446 : 364303 : return do_freeze;
7447 : : }
7448 : :
7449 : : /*
7450 : : * For a given MultiXactId, return the hint bits that should be set in the
7451 : : * tuple's infomask.
7452 : : *
7453 : : * Normally this should be called for a multixact that was just created, and
7454 : : * so is on our local cache, so the GetMembers call is fast.
7455 : : */
7456 : : static void
4661 7457 : 1206 : GetMultiXactIdHintBits(MultiXactId multi, uint16 *new_infomask,
7458 : : uint16 *new_infomask2)
7459 : : {
7460 : : int nmembers;
7461 : : MultiXactMember *members;
7462 : : int i;
4535 bruce@momjian.us 7463 : 1206 : uint16 bits = HEAP_XMAX_IS_MULTI;
7464 : 1206 : uint16 bits2 = 0;
7465 : 1206 : bool has_update = false;
7466 : 1206 : LockTupleMode strongest = LockTupleKeyShare;
7467 : :
7468 : : /*
7469 : : * We only use this in multis we just created, so they cannot be values
7470 : : * pre-pg_upgrade.
7471 : : */
4109 alvherre@alvh.no-ip. 7472 : 1206 : nmembers = GetMultiXactIdMembers(multi, &members, false, false);
7473 : :
4661 7474 [ + + ]: 3702 : for (i = 0; i < nmembers; i++)
7475 : : {
7476 : : LockTupleMode mode;
7477 : :
7478 : : /*
7479 : : * Remember the strongest lock mode held by any member of the
7480 : : * multixact.
7481 : : */
4653 7482 : 2496 : mode = TUPLOCK_from_mxstatus(members[i].status);
7483 [ + + ]: 2496 : if (mode > strongest)
7484 : 661 : strongest = mode;
7485 : :
7486 : : /* See what other bits we need */
4661 7487 [ + + + + : 2496 : switch (members[i].status)
- ]
7488 : : {
7489 : 2305 : case MultiXactStatusForKeyShare:
7490 : : case MultiXactStatusForShare:
7491 : : case MultiXactStatusForNoKeyUpdate:
7492 : 2305 : break;
7493 : :
7494 : 52 : case MultiXactStatusForUpdate:
7495 : 52 : bits2 |= HEAP_KEYS_UPDATED;
7496 : 52 : break;
7497 : :
7498 : 129 : case MultiXactStatusNoKeyUpdate:
7499 : 129 : has_update = true;
7500 : 129 : break;
7501 : :
7502 : 10 : case MultiXactStatusUpdate:
7503 : 10 : bits2 |= HEAP_KEYS_UPDATED;
7504 : 10 : has_update = true;
7505 : 10 : break;
7506 : : }
7507 : : }
7508 : :
4653 7509 [ + + + + ]: 1206 : if (strongest == LockTupleExclusive ||
7510 : : strongest == LockTupleNoKeyExclusive)
7511 : 219 : bits |= HEAP_XMAX_EXCL_LOCK;
7512 [ + + ]: 987 : else if (strongest == LockTupleShare)
7513 : 439 : bits |= HEAP_XMAX_SHR_LOCK;
7514 [ + - ]: 548 : else if (strongest == LockTupleKeyShare)
7515 : 548 : bits |= HEAP_XMAX_KEYSHR_LOCK;
7516 : :
4661 7517 [ + + ]: 1206 : if (!has_update)
7518 : 1067 : bits |= HEAP_XMAX_LOCK_ONLY;
7519 : :
7520 [ + - ]: 1206 : if (nmembers > 0)
7521 : 1206 : pfree(members);
7522 : :
7523 : 1206 : *new_infomask = bits;
7524 : 1206 : *new_infomask2 = bits2;
7525 : 1206 : }
7526 : :
7527 : : /*
7528 : : * MultiXactIdGetUpdateXid
7529 : : *
7530 : : * Given a multixact Xmax and corresponding infomask, which does not have the
7531 : : * HEAP_XMAX_LOCK_ONLY bit set, obtain and return the Xid of the updating
7532 : : * transaction.
7533 : : *
7534 : : * Caller is expected to check the status of the updating transaction, if
7535 : : * necessary.
7536 : : */
7537 : : static TransactionId
7538 : 533 : MultiXactIdGetUpdateXid(TransactionId xmax, uint16 t_infomask)
7539 : : {
4535 bruce@momjian.us 7540 : 533 : TransactionId update_xact = InvalidTransactionId;
7541 : : MultiXactMember *members;
7542 : : int nmembers;
7543 : :
4661 alvherre@alvh.no-ip. 7544 [ - + ]: 533 : Assert(!(t_infomask & HEAP_XMAX_LOCK_ONLY));
7545 [ - + ]: 533 : Assert(t_infomask & HEAP_XMAX_IS_MULTI);
7546 : :
7547 : : /*
7548 : : * Since we know the LOCK_ONLY bit is not set, this cannot be a multi from
7549 : : * pre-pg_upgrade.
7550 : : */
4109 7551 : 533 : nmembers = GetMultiXactIdMembers(xmax, &members, false, false);
7552 : :
4661 7553 [ + - ]: 533 : if (nmembers > 0)
7554 : : {
7555 : : int i;
7556 : :
7557 [ + + ]: 2003 : for (i = 0; i < nmembers; i++)
7558 : : {
7559 : : /* Ignore lockers */
4351 7560 [ + + ]: 1470 : if (!ISUPDATE_from_mxstatus(members[i].status))
4661 7561 : 937 : continue;
7562 : :
7563 : : /* there can be at most one updater */
7564 [ - + ]: 533 : Assert(update_xact == InvalidTransactionId);
7565 : 533 : update_xact = members[i].xid;
7566 : : #ifndef USE_ASSERT_CHECKING
7567 : :
7568 : : /*
7569 : : * in an assert-enabled build, walk the whole array to ensure
7570 : : * there's no other updater.
7571 : : */
7572 : : break;
7573 : : #endif
7574 : : }
7575 : :
7576 : 533 : pfree(members);
7577 : : }
7578 : :
7579 : 533 : return update_xact;
7580 : : }
7581 : :
7582 : : /*
7583 : : * HeapTupleGetUpdateXid
7584 : : * As above, but use a HeapTupleHeader
7585 : : *
7586 : : * See also HeapTupleHeaderGetUpdateXid, which can be used without previously
7587 : : * checking the hint bits.
7588 : : */
7589 : : TransactionId
278 peter@eisentraut.org 7590 : 524 : HeapTupleGetUpdateXid(const HeapTupleHeaderData *tup)
7591 : : {
7592 : 524 : return MultiXactIdGetUpdateXid(HeapTupleHeaderGetRawXmax(tup),
7593 : 524 : tup->t_infomask);
7594 : : }
7595 : :
7596 : : /*
7597 : : * Does the given multixact conflict with the current transaction grabbing a
7598 : : * tuple lock of the given strength?
7599 : : *
7600 : : * The passed infomask pairs up with the given multixact in the tuple header.
7601 : : *
7602 : : * If current_is_member is not NULL, it is set to 'true' if the current
7603 : : * transaction is a member of the given multixact.
7604 : : */
7605 : : static bool
3959 alvherre@alvh.no-ip. 7606 : 99 : DoesMultiXactIdConflict(MultiXactId multi, uint16 infomask,
7607 : : LockTupleMode lockmode, bool *current_is_member)
7608 : : {
7609 : : int nmembers;
7610 : : MultiXactMember *members;
3811 bruce@momjian.us 7611 : 99 : bool result = false;
7612 : 99 : LOCKMODE wanted = tupleLockExtraInfo[lockmode].hwlock;
7613 : :
3413 alvherre@alvh.no-ip. 7614 [ - + ]: 99 : if (HEAP_LOCKED_UPGRADED(infomask))
3413 alvherre@alvh.no-ip. 7615 :UBC 0 : return false;
7616 : :
3413 alvherre@alvh.no-ip. 7617 :CBC 99 : nmembers = GetMultiXactIdMembers(multi, &members, false,
3959 7618 : 99 : HEAP_XMAX_IS_LOCKED_ONLY(infomask));
7619 [ + - ]: 99 : if (nmembers >= 0)
7620 : : {
7621 : : int i;
7622 : :
7623 [ + + ]: 309 : for (i = 0; i < nmembers; i++)
7624 : : {
7625 : : TransactionId memxid;
7626 : : LOCKMODE memlockmode;
7627 : :
2324 7628 [ + + + + : 217 : if (result && (current_is_member == NULL || *current_is_member))
+ - ]
7629 : : break;
7630 : :
7631 : 210 : memlockmode = LOCKMODE_from_mxstatus(members[i].status);
7632 : :
7633 : : /* ignore members from current xact (but track their presence) */
2326 7634 : 210 : memxid = members[i].xid;
7635 [ + + ]: 210 : if (TransactionIdIsCurrentTransactionId(memxid))
7636 : : {
2324 7637 [ + + ]: 92 : if (current_is_member != NULL)
7638 : 78 : *current_is_member = true;
7639 : 92 : continue;
7640 : : }
7641 [ + + ]: 118 : else if (result)
7642 : 8 : continue;
7643 : :
7644 : : /* ignore members that don't conflict with the lock we want */
7645 [ + + ]: 110 : if (!DoLockModesConflict(memlockmode, wanted))
2326 7646 : 71 : continue;
7647 : :
3959 7648 [ + + ]: 39 : if (ISUPDATE_from_mxstatus(members[i].status))
7649 : : {
7650 : : /* ignore aborted updaters */
7651 [ + + ]: 17 : if (TransactionIdDidAbort(memxid))
7652 : 1 : continue;
7653 : : }
7654 : : else
7655 : : {
7656 : : /* ignore lockers-only that are no longer in progress */
7657 [ + + ]: 22 : if (!TransactionIdIsInProgress(memxid))
7658 : 7 : continue;
7659 : : }
7660 : :
7661 : : /*
7662 : : * Whatever remains are either live lockers that conflict with our
7663 : : * wanted lock, and updaters that are not aborted. Those conflict
7664 : : * with what we want. Set up to return true, but keep going to
7665 : : * look for the current transaction among the multixact members,
7666 : : * if needed.
7667 : : */
7668 : 31 : result = true;
7669 : : }
7670 : 99 : pfree(members);
7671 : : }
7672 : :
7673 : 99 : return result;
7674 : : }
7675 : :
7676 : : /*
7677 : : * Do_MultiXactIdWait
7678 : : * Actual implementation for the two functions below.
7679 : : *
7680 : : * 'multi', 'status' and 'infomask' indicate what to sleep on (the status is
7681 : : * needed to ensure we only sleep on conflicting members, and the infomask is
7682 : : * used to optimize multixact access in case it's a lock-only multi); 'nowait'
7683 : : * indicates whether to use conditional lock acquisition, to allow callers to
7684 : : * fail if lock is unavailable. 'rel', 'ctid' and 'oper' are used to set up
7685 : : * context information for error messages. 'remaining', if not NULL, receives
7686 : : * the number of members that are still running, including any (non-aborted)
7687 : : * subtransactions of our own transaction. 'logLockFailure' indicates whether
7688 : : * to log details when a lock acquisition fails with 'nowait' enabled.
7689 : : *
7690 : : * We do this by sleeping on each member using XactLockTableWait. Any
7691 : : * members that belong to the current backend are *not* waited for, however;
7692 : : * this would not merely be useless but would lead to Assert failure inside
7693 : : * XactLockTableWait. By the time this returns, it is certain that all
7694 : : * transactions *of other backends* that were members of the MultiXactId
7695 : : * that conflict with the requested status are dead (and no new ones can have
7696 : : * been added, since it is not legal to add members to an existing
7697 : : * MultiXactId).
7698 : : *
7699 : : * But by the time we finish sleeping, someone else may have changed the Xmax
7700 : : * of the containing tuple, so the caller needs to iterate on us somehow.
7701 : : *
7702 : : * Note that in case we return false, the number of remaining members is
7703 : : * not to be trusted.
7704 : : */
7705 : : static bool
4661 7706 : 58 : Do_MultiXactIdWait(MultiXactId multi, MultiXactStatus status,
7707 : : uint16 infomask, bool nowait,
7708 : : Relation rel, ItemPointer ctid, XLTW_Oper oper,
7709 : : int *remaining, bool logLockFailure)
7710 : : {
7711 : 58 : bool result = true;
7712 : : MultiXactMember *members;
7713 : : int nmembers;
7714 : 58 : int remain = 0;
7715 : :
7716 : : /* for pre-pg_upgrade tuples, no need to sleep at all */
3413 7717 [ + - ]: 58 : nmembers = HEAP_LOCKED_UPGRADED(infomask) ? -1 :
7718 : 58 : GetMultiXactIdMembers(multi, &members, false,
7719 : 58 : HEAP_XMAX_IS_LOCKED_ONLY(infomask));
7720 : :
4661 7721 [ + - ]: 58 : if (nmembers >= 0)
7722 : : {
7723 : : int i;
7724 : :
7725 [ + + ]: 187 : for (i = 0; i < nmembers; i++)
7726 : : {
7727 : 133 : TransactionId memxid = members[i].xid;
7728 : 133 : MultiXactStatus memstatus = members[i].status;
7729 : :
7730 [ + + ]: 133 : if (TransactionIdIsCurrentTransactionId(memxid))
7731 : : {
7732 : 24 : remain++;
7733 : 24 : continue;
7734 : : }
7735 : :
7736 [ + + ]: 109 : if (!DoLockModesConflict(LOCKMODE_from_mxstatus(memstatus),
7737 : 109 : LOCKMODE_from_mxstatus(status)))
7738 : : {
7739 [ + + + - ]: 22 : if (remaining && TransactionIdIsInProgress(memxid))
7740 : 8 : remain++;
7741 : 22 : continue;
7742 : : }
7743 : :
7744 : : /*
7745 : : * This member conflicts with our multi, so we have to sleep (or
7746 : : * return failure, if asked to avoid waiting.)
7747 : : *
7748 : : * Note that we don't set up an error context callback ourselves,
7749 : : * but instead we pass the info down to XactLockTableWait. This
7750 : : * might seem a bit wasteful because the context is set up and
7751 : : * tore down for each member of the multixact, but in reality it
7752 : : * should be barely noticeable, and it avoids duplicate code.
7753 : : */
7754 [ + + ]: 87 : if (nowait)
7755 : : {
228 fujii@postgresql.org 7756 : 4 : result = ConditionalXactLockTableWait(memxid, logLockFailure);
4661 alvherre@alvh.no-ip. 7757 [ + - ]: 4 : if (!result)
7758 : 4 : break;
7759 : : }
7760 : : else
4241 7761 : 83 : XactLockTableWait(memxid, rel, ctid, oper);
7762 : : }
7763 : :
4661 7764 : 58 : pfree(members);
7765 : : }
7766 : :
7767 [ + + ]: 58 : if (remaining)
7768 : 10 : *remaining = remain;
7769 : :
7770 : 58 : return result;
7771 : : }
7772 : :
7773 : : /*
7774 : : * MultiXactIdWait
7775 : : * Sleep on a MultiXactId.
7776 : : *
7777 : : * By the time we finish sleeping, someone else may have changed the Xmax
7778 : : * of the containing tuple, so the caller needs to iterate on us somehow.
7779 : : *
7780 : : * We return (in *remaining, if not NULL) the number of members that are still
7781 : : * running, including any (non-aborted) subtransactions of our own transaction.
7782 : : */
7783 : : static void
4241 7784 : 54 : MultiXactIdWait(MultiXactId multi, MultiXactStatus status, uint16 infomask,
7785 : : Relation rel, ItemPointer ctid, XLTW_Oper oper,
7786 : : int *remaining)
7787 : : {
7788 : 54 : (void) Do_MultiXactIdWait(multi, status, infomask, false,
7789 : : rel, ctid, oper, remaining, false);
4661 7790 : 54 : }
7791 : :
7792 : : /*
7793 : : * ConditionalMultiXactIdWait
7794 : : * As above, but only lock if we can get the lock without blocking.
7795 : : *
7796 : : * By the time we finish sleeping, someone else may have changed the Xmax
7797 : : * of the containing tuple, so the caller needs to iterate on us somehow.
7798 : : *
7799 : : * If the multixact is now all gone, return true. Returns false if some
7800 : : * transactions might still be running.
7801 : : *
7802 : : * We return (in *remaining, if not NULL) the number of members that are still
7803 : : * running, including any (non-aborted) subtransactions of our own transaction.
7804 : : */
7805 : : static bool
7806 : 4 : ConditionalMultiXactIdWait(MultiXactId multi, MultiXactStatus status,
7807 : : uint16 infomask, Relation rel, int *remaining,
7808 : : bool logLockFailure)
7809 : : {
4241 7810 : 4 : return Do_MultiXactIdWait(multi, status, infomask, true,
7811 : : rel, NULL, XLTW_None, remaining, logLockFailure);
7812 : : }
7813 : :
7814 : : /*
7815 : : * heap_tuple_needs_eventual_freeze
7816 : : *
7817 : : * Check to see whether any of the XID fields of a tuple (xmin, xmax, xvac)
7818 : : * will eventually require freezing (if tuple isn't removed by pruning first).
7819 : : */
7820 : : bool
3528 rhaas@postgresql.org 7821 : 2220049 : heap_tuple_needs_eventual_freeze(HeapTupleHeader tuple)
7822 : : {
7823 : : TransactionId xid;
7824 : :
7825 : : /*
7826 : : * If xmin is a normal transaction ID, this tuple is definitely not
7827 : : * frozen.
7828 : : */
7829 : 2220049 : xid = HeapTupleHeaderGetXmin(tuple);
7830 [ + + ]: 2220049 : if (TransactionIdIsNormal(xid))
7831 : 14927 : return true;
7832 : :
7833 : : /*
7834 : : * If xmax is a valid xact or multixact, this tuple is also not frozen.
7835 : : */
7836 [ + + ]: 2205122 : if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
7837 : : {
7838 : : MultiXactId multi;
7839 : :
7840 : 2 : multi = HeapTupleHeaderGetRawXmax(tuple);
7841 [ + - ]: 2 : if (MultiXactIdIsValid(multi))
7842 : 2 : return true;
7843 : : }
7844 : : else
7845 : : {
7846 : 2205120 : xid = HeapTupleHeaderGetRawXmax(tuple);
7847 [ + + ]: 2205120 : if (TransactionIdIsNormal(xid))
7848 : 11 : return true;
7849 : : }
7850 : :
7851 [ - + ]: 2205109 : if (tuple->t_infomask & HEAP_MOVED)
7852 : : {
3528 rhaas@postgresql.org 7853 :UBC 0 : xid = HeapTupleHeaderGetXvac(tuple);
7854 [ # # ]: 0 : if (TransactionIdIsNormal(xid))
7855 : 0 : return true;
7856 : : }
7857 : :
3528 rhaas@postgresql.org 7858 :CBC 2205109 : return false;
7859 : : }
7860 : :
7861 : : /*
7862 : : * heap_tuple_should_freeze
7863 : : *
7864 : : * Return value indicates if heap_prepare_freeze_tuple sibling function would
7865 : : * (or should) force freezing of the heap page that contains caller's tuple.
7866 : : * Tuple header XIDs/MXIDs < FreezeLimit/MultiXactCutoff trigger freezing.
7867 : : * This includes (xmin, xmax, xvac) fields, as well as MultiXact member XIDs.
7868 : : *
7869 : : * The *NoFreezePageRelfrozenXid and *NoFreezePageRelminMxid input/output
7870 : : * arguments help VACUUM track the oldest extant XID/MXID remaining in rel.
7871 : : * Our working assumption is that caller won't decide to freeze this tuple.
7872 : : * It's up to caller to only ratchet back its own top-level trackers after the
7873 : : * point that it fully commits to not freezing the tuple/page in question.
7874 : : */
7875 : : bool
1035 pg@bowt.ie 7876 : 2032530 : heap_tuple_should_freeze(HeapTupleHeader tuple,
7877 : : const struct VacuumCutoffs *cutoffs,
7878 : : TransactionId *NoFreezePageRelfrozenXid,
7879 : : MultiXactId *NoFreezePageRelminMxid)
7880 : : {
7881 : : TransactionId xid;
7882 : : MultiXactId multi;
1041 7883 : 2032530 : bool freeze = false;
7884 : :
7885 : : /* First deal with xmin */
5104 rhaas@postgresql.org 7886 : 2032530 : xid = HeapTupleHeaderGetXmin(tuple);
1304 pg@bowt.ie 7887 [ + + ]: 2032530 : if (TransactionIdIsNormal(xid))
7888 : : {
1041 7889 [ - + ]: 2032281 : Assert(TransactionIdPrecedesOrEquals(cutoffs->relfrozenxid, xid));
1035 7890 [ + + ]: 2032281 : if (TransactionIdPrecedes(xid, *NoFreezePageRelfrozenXid))
7891 : 21223 : *NoFreezePageRelfrozenXid = xid;
1041 7892 [ + + ]: 2032281 : if (TransactionIdPrecedes(xid, cutoffs->FreezeLimit))
7893 : 18796 : freeze = true;
7894 : : }
7895 : :
7896 : : /* Now deal with xmax */
1304 7897 : 2032530 : xid = InvalidTransactionId;
7898 : 2032530 : multi = InvalidMultiXactId;
7899 [ + + ]: 2032530 : if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
4352 alvherre@alvh.no-ip. 7900 : 2 : multi = HeapTupleHeaderGetRawXmax(tuple);
7901 : : else
1304 pg@bowt.ie 7902 : 2032528 : xid = HeapTupleHeaderGetRawXmax(tuple);
7903 : :
7904 [ + + ]: 2032530 : if (TransactionIdIsNormal(xid))
7905 : : {
1041 7906 [ - + ]: 249916 : Assert(TransactionIdPrecedesOrEquals(cutoffs->relfrozenxid, xid));
7907 : : /* xmax is a non-permanent XID */
1035 7908 [ + + ]: 249916 : if (TransactionIdPrecedes(xid, *NoFreezePageRelfrozenXid))
7909 : 3 : *NoFreezePageRelfrozenXid = xid;
1041 7910 [ + + ]: 249916 : if (TransactionIdPrecedes(xid, cutoffs->FreezeLimit))
7911 : 29 : freeze = true;
7912 : : }
1304 7913 [ + + ]: 1782614 : else if (!MultiXactIdIsValid(multi))
7914 : : {
7915 : : /* xmax is a permanent XID or invalid MultiXactId/XID */
7916 : : }
7917 [ - + ]: 2 : else if (HEAP_LOCKED_UPGRADED(tuple->t_infomask))
7918 : : {
7919 : : /* xmax is a pg_upgrade'd MultiXact, which can't have updater XID */
1035 pg@bowt.ie 7920 [ # # ]:UBC 0 : if (MultiXactIdPrecedes(multi, *NoFreezePageRelminMxid))
7921 : 0 : *NoFreezePageRelminMxid = multi;
7922 : : /* heap_prepare_freeze_tuple always freezes pg_upgrade'd xmax */
1041 7923 : 0 : freeze = true;
7924 : : }
7925 : : else
7926 : : {
7927 : : /* xmax is a MultiXactId that may have an updater XID */
7928 : : MultiXactMember *members;
7929 : : int nmembers;
7930 : :
1041 pg@bowt.ie 7931 [ - + ]:CBC 2 : Assert(MultiXactIdPrecedesOrEquals(cutoffs->relminmxid, multi));
1035 7932 [ + - ]: 2 : if (MultiXactIdPrecedes(multi, *NoFreezePageRelminMxid))
7933 : 2 : *NoFreezePageRelminMxid = multi;
1041 7934 [ + - ]: 2 : if (MultiXactIdPrecedes(multi, cutoffs->MultiXactCutoff))
7935 : 2 : freeze = true;
7936 : :
7937 : : /* need to check whether any member of the mxact is old */
1304 7938 : 2 : nmembers = GetMultiXactIdMembers(multi, &members, false,
7939 : 2 : HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask));
7940 : :
7941 [ + + ]: 5 : for (int i = 0; i < nmembers; i++)
7942 : : {
7943 : 3 : xid = members[i].xid;
1041 7944 [ - + ]: 3 : Assert(TransactionIdPrecedesOrEquals(cutoffs->relfrozenxid, xid));
1035 7945 [ - + ]: 3 : if (TransactionIdPrecedes(xid, *NoFreezePageRelfrozenXid))
1035 pg@bowt.ie 7946 :UBC 0 : *NoFreezePageRelfrozenXid = xid;
1041 pg@bowt.ie 7947 [ - + ]:CBC 3 : if (TransactionIdPrecedes(xid, cutoffs->FreezeLimit))
1041 pg@bowt.ie 7948 :UBC 0 : freeze = true;
7949 : : }
1304 pg@bowt.ie 7950 [ + + ]:CBC 2 : if (nmembers > 0)
7951 : 1 : pfree(members);
7952 : : }
7953 : :
5104 rhaas@postgresql.org 7954 [ - + ]: 2032530 : if (tuple->t_infomask & HEAP_MOVED)
7955 : : {
5104 rhaas@postgresql.org 7956 :UBC 0 : xid = HeapTupleHeaderGetXvac(tuple);
1304 pg@bowt.ie 7957 [ # # ]: 0 : if (TransactionIdIsNormal(xid))
7958 : : {
1041 7959 [ # # ]: 0 : Assert(TransactionIdPrecedesOrEquals(cutoffs->relfrozenxid, xid));
1035 7960 [ # # ]: 0 : if (TransactionIdPrecedes(xid, *NoFreezePageRelfrozenXid))
7961 : 0 : *NoFreezePageRelfrozenXid = xid;
7962 : : /* heap_prepare_freeze_tuple forces xvac freezing */
1041 7963 : 0 : freeze = true;
7964 : : }
7965 : : }
7966 : :
1041 pg@bowt.ie 7967 :CBC 2032530 : return freeze;
7968 : : }
7969 : :
7970 : : /*
7971 : : * Maintain snapshotConflictHorizon for caller by ratcheting forward its value
7972 : : * using any committed XIDs contained in 'tuple', an obsolescent heap tuple
7973 : : * that caller is in the process of physically removing, e.g. via HOT pruning
7974 : : * or index deletion.
7975 : : *
7976 : : * Caller must initialize its value to InvalidTransactionId, which is
7977 : : * generally interpreted as "definitely no need for a recovery conflict".
7978 : : * Final value must reflect all heap tuples that caller will physically remove
7979 : : * (or remove TID references to) via its ongoing pruning/deletion operation.
7980 : : * ResolveRecoveryConflictWithSnapshot() is passed the final value (taken from
7981 : : * caller's WAL record) by REDO routine when it replays caller's operation.
7982 : : */
7983 : : void
1076 7984 : 1519472 : HeapTupleHeaderAdvanceConflictHorizon(HeapTupleHeader tuple,
7985 : : TransactionId *snapshotConflictHorizon)
7986 : : {
5792 simon@2ndQuadrant.co 7987 : 1519472 : TransactionId xmin = HeapTupleHeaderGetXmin(tuple);
4661 alvherre@alvh.no-ip. 7988 : 1519472 : TransactionId xmax = HeapTupleHeaderGetUpdateXid(tuple);
5792 simon@2ndQuadrant.co 7989 : 1519472 : TransactionId xvac = HeapTupleHeaderGetXvac(tuple);
7990 : :
5741 tgl@sss.pgh.pa.us 7991 [ - + ]: 1519472 : if (tuple->t_infomask & HEAP_MOVED)
7992 : : {
1076 pg@bowt.ie 7993 [ # # ]:UBC 0 : if (TransactionIdPrecedes(*snapshotConflictHorizon, xvac))
7994 : 0 : *snapshotConflictHorizon = xvac;
7995 : : }
7996 : :
7997 : : /*
7998 : : * Ignore tuples inserted by an aborted transaction or if the tuple was
7999 : : * updated/deleted by the inserting transaction.
8000 : : *
8001 : : * Look for a committed hint bit, or if no xmin bit is set, check clog.
8002 : : */
4328 rhaas@postgresql.org 8003 [ + + ]:CBC 1519472 : if (HeapTupleHeaderXminCommitted(tuple) ||
8004 [ + + + - ]: 95786 : (!HeapTupleHeaderXminInvalid(tuple) && TransactionIdDidCommit(xmin)))
8005 : : {
5437 simon@2ndQuadrant.co 8006 [ + + + + ]: 2748132 : if (xmax != xmin &&
1076 pg@bowt.ie 8007 : 1306307 : TransactionIdFollows(xmax, *snapshotConflictHorizon))
8008 : 97529 : *snapshotConflictHorizon = xmax;
8009 : : }
5792 simon@2ndQuadrant.co 8010 : 1519472 : }
8011 : :
8012 : : #ifdef USE_PREFETCH
8013 : : /*
8014 : : * Helper function for heap_index_delete_tuples. Issues prefetch requests for
8015 : : * prefetch_count buffers. The prefetch_state keeps track of all the buffers
8016 : : * we can prefetch, and which have already been prefetched; each call to this
8017 : : * function picks up where the previous call left off.
8018 : : *
8019 : : * Note: we expect the deltids array to be sorted in an order that groups TIDs
8020 : : * by heap block, with all TIDs for each block appearing together in exactly
8021 : : * one group.
8022 : : */
8023 : : static void
1749 pg@bowt.ie 8024 : 19009 : index_delete_prefetch_buffer(Relation rel,
8025 : : IndexDeletePrefetchState *prefetch_state,
8026 : : int prefetch_count)
8027 : : {
2408 andres@anarazel.de 8028 : 19009 : BlockNumber cur_hblkno = prefetch_state->cur_hblkno;
8029 : 19009 : int count = 0;
8030 : : int i;
1749 pg@bowt.ie 8031 : 19009 : int ndeltids = prefetch_state->ndeltids;
8032 : 19009 : TM_IndexDelete *deltids = prefetch_state->deltids;
8033 : :
2408 andres@anarazel.de 8034 : 19009 : for (i = prefetch_state->next_item;
1749 pg@bowt.ie 8035 [ + + + + ]: 667358 : i < ndeltids && count < prefetch_count;
2408 andres@anarazel.de 8036 : 648349 : i++)
8037 : : {
1749 pg@bowt.ie 8038 : 648349 : ItemPointer htid = &deltids[i].tid;
8039 : :
2408 andres@anarazel.de 8040 [ + + + + ]: 1291107 : if (cur_hblkno == InvalidBlockNumber ||
8041 : 642758 : ItemPointerGetBlockNumber(htid) != cur_hblkno)
8042 : : {
8043 : 17423 : cur_hblkno = ItemPointerGetBlockNumber(htid);
8044 : 17423 : PrefetchBuffer(rel, MAIN_FORKNUM, cur_hblkno);
8045 : 17423 : count++;
8046 : : }
8047 : : }
8048 : :
8049 : : /*
8050 : : * Save the prefetch position so that next time we can continue from that
8051 : : * position.
8052 : : */
8053 : 19009 : prefetch_state->next_item = i;
8054 : 19009 : prefetch_state->cur_hblkno = cur_hblkno;
8055 : 19009 : }
8056 : : #endif
8057 : :
8058 : : /*
8059 : : * Helper function for heap_index_delete_tuples. Checks for index corruption
8060 : : * involving an invalid TID in index AM caller's index page.
8061 : : *
8062 : : * This is an ideal place for these checks. The index AM must hold a buffer
8063 : : * lock on the index page containing the TIDs we examine here, so we don't
8064 : : * have to worry about concurrent VACUUMs at all. We can be sure that the
8065 : : * index is corrupt when htid points directly to an LP_UNUSED item or
8066 : : * heap-only tuple, which is not the case during standard index scans.
8067 : : */
8068 : : static inline void
1454 pg@bowt.ie 8069 : 536293 : index_delete_check_htid(TM_IndexDeleteOp *delstate,
8070 : : Page page, OffsetNumber maxoff,
8071 : : ItemPointer htid, TM_IndexStatus *istatus)
8072 : : {
8073 : 536293 : OffsetNumber indexpagehoffnum = ItemPointerGetOffsetNumber(htid);
8074 : : ItemId iid;
8075 : :
8076 [ + - + - : 536293 : Assert(OffsetNumberIsValid(istatus->idxoffnum));
- + ]
8077 : :
8078 [ - + ]: 536293 : if (unlikely(indexpagehoffnum > maxoff))
1454 pg@bowt.ie 8079 [ # # ]:UBC 0 : ereport(ERROR,
8080 : : (errcode(ERRCODE_INDEX_CORRUPTED),
8081 : : errmsg_internal("heap tid from index tuple (%u,%u) points past end of heap page line pointer array at offset %u of block %u in index \"%s\"",
8082 : : ItemPointerGetBlockNumber(htid),
8083 : : indexpagehoffnum,
8084 : : istatus->idxoffnum, delstate->iblknum,
8085 : : RelationGetRelationName(delstate->irel))));
8086 : :
1454 pg@bowt.ie 8087 :CBC 536293 : iid = PageGetItemId(page, indexpagehoffnum);
8088 [ - + ]: 536293 : if (unlikely(!ItemIdIsUsed(iid)))
1454 pg@bowt.ie 8089 [ # # ]:UBC 0 : ereport(ERROR,
8090 : : (errcode(ERRCODE_INDEX_CORRUPTED),
8091 : : errmsg_internal("heap tid from index tuple (%u,%u) points to unused heap page item at offset %u of block %u in index \"%s\"",
8092 : : ItemPointerGetBlockNumber(htid),
8093 : : indexpagehoffnum,
8094 : : istatus->idxoffnum, delstate->iblknum,
8095 : : RelationGetRelationName(delstate->irel))));
8096 : :
1454 pg@bowt.ie 8097 [ + + ]:CBC 536293 : if (ItemIdHasStorage(iid))
8098 : : {
8099 : : HeapTupleHeader htup;
8100 : :
8101 [ - + ]: 318239 : Assert(ItemIdIsNormal(iid));
8102 : 318239 : htup = (HeapTupleHeader) PageGetItem(page, iid);
8103 : :
8104 [ - + ]: 318239 : if (unlikely(HeapTupleHeaderIsHeapOnly(htup)))
1454 pg@bowt.ie 8105 [ # # ]:UBC 0 : ereport(ERROR,
8106 : : (errcode(ERRCODE_INDEX_CORRUPTED),
8107 : : errmsg_internal("heap tid from index tuple (%u,%u) points to heap-only tuple at offset %u of block %u in index \"%s\"",
8108 : : ItemPointerGetBlockNumber(htid),
8109 : : indexpagehoffnum,
8110 : : istatus->idxoffnum, delstate->iblknum,
8111 : : RelationGetRelationName(delstate->irel))));
8112 : : }
1454 pg@bowt.ie 8113 :CBC 536293 : }
8114 : :
8115 : : /*
8116 : : * heapam implementation of tableam's index_delete_tuples interface.
8117 : : *
8118 : : * This helper function is called by index AMs during index tuple deletion.
8119 : : * See tableam header comments for an explanation of the interface implemented
8120 : : * here and a general theory of operation. Note that each call here is either
8121 : : * a simple index deletion call, or a bottom-up index deletion call.
8122 : : *
8123 : : * It's possible for this to generate a fair amount of I/O, since we may be
8124 : : * deleting hundreds of tuples from a single index block. To amortize that
8125 : : * cost to some degree, this uses prefetching and combines repeat accesses to
8126 : : * the same heap block.
8127 : : */
8128 : : TransactionId
1749 8129 : 5591 : heap_index_delete_tuples(Relation rel, TM_IndexDeleteOp *delstate)
8130 : : {
8131 : : /* Initial assumption is that earlier pruning took care of conflict */
1076 8132 : 5591 : TransactionId snapshotConflictHorizon = InvalidTransactionId;
1763 8133 : 5591 : BlockNumber blkno = InvalidBlockNumber;
2408 andres@anarazel.de 8134 : 5591 : Buffer buf = InvalidBuffer;
1763 pg@bowt.ie 8135 : 5591 : Page page = NULL;
8136 : 5591 : OffsetNumber maxoff = InvalidOffsetNumber;
8137 : : TransactionId priorXmax;
8138 : : #ifdef USE_PREFETCH
8139 : : IndexDeletePrefetchState prefetch_state;
8140 : : int prefetch_distance;
8141 : : #endif
8142 : : SnapshotData SnapshotNonVacuumable;
1749 8143 : 5591 : int finalndeltids = 0,
8144 : 5591 : nblocksaccessed = 0;
8145 : :
8146 : : /* State that's only used in bottom-up index deletion case */
8147 : 5591 : int nblocksfavorable = 0;
8148 : 5591 : int curtargetfreespace = delstate->bottomupfreespace,
8149 : 5591 : lastfreespace = 0,
8150 : 5591 : actualfreespace = 0;
8151 : 5591 : bool bottomup_final_block = false;
8152 : :
8153 : 5591 : InitNonVacuumableSnapshot(SnapshotNonVacuumable, GlobalVisTestFor(rel));
8154 : :
8155 : : /* Sort caller's deltids array by TID for further processing */
8156 : 5591 : index_delete_sort(delstate);
8157 : :
8158 : : /*
8159 : : * Bottom-up case: resort deltids array in an order attuned to where the
8160 : : * greatest number of promising TIDs are to be found, and determine how
8161 : : * many blocks from the start of sorted array should be considered
8162 : : * favorable. This will also shrink the deltids array in order to
8163 : : * eliminate completely unfavorable blocks up front.
8164 : : */
8165 [ + + ]: 5591 : if (delstate->bottomup)
8166 : 1920 : nblocksfavorable = bottomup_sort_and_shrink(delstate);
8167 : :
8168 : : #ifdef USE_PREFETCH
8169 : : /* Initialize prefetch state. */
2408 andres@anarazel.de 8170 : 5591 : prefetch_state.cur_hblkno = InvalidBlockNumber;
8171 : 5591 : prefetch_state.next_item = 0;
1749 pg@bowt.ie 8172 : 5591 : prefetch_state.ndeltids = delstate->ndeltids;
8173 : 5591 : prefetch_state.deltids = delstate->deltids;
8174 : :
8175 : : /*
8176 : : * Determine the prefetch distance that we will attempt to maintain.
8177 : : *
8178 : : * Since the caller holds a buffer lock somewhere in rel, we'd better make
8179 : : * sure that isn't a catalog relation before we call code that does
8180 : : * syscache lookups, to avoid risk of deadlock.
8181 : : */
2401 tmunro@postgresql.or 8182 [ + + ]: 5591 : if (IsCatalogRelation(rel))
2052 8183 : 3997 : prefetch_distance = maintenance_io_concurrency;
8184 : : else
8185 : : prefetch_distance =
8186 : 1594 : get_tablespace_maintenance_io_concurrency(rel->rd_rel->reltablespace);
8187 : :
8188 : : /* Cap initial prefetch distance for bottom-up deletion caller */
1749 pg@bowt.ie 8189 [ + + ]: 5591 : if (delstate->bottomup)
8190 : : {
8191 [ - + ]: 1920 : Assert(nblocksfavorable >= 1);
8192 [ - + ]: 1920 : Assert(nblocksfavorable <= BOTTOMUP_MAX_NBLOCKS);
8193 : 1920 : prefetch_distance = Min(prefetch_distance, nblocksfavorable);
8194 : : }
8195 : :
8196 : : /* Start prefetching. */
8197 : 5591 : index_delete_prefetch_buffer(rel, &prefetch_state, prefetch_distance);
8198 : : #endif
8199 : :
8200 : : /* Iterate over deltids, determine which to delete, check their horizon */
8201 [ - + ]: 5591 : Assert(delstate->ndeltids > 0);
8202 [ + + ]: 541884 : for (int i = 0; i < delstate->ndeltids; i++)
8203 : : {
8204 : 538213 : TM_IndexDelete *ideltid = &delstate->deltids[i];
8205 : 538213 : TM_IndexStatus *istatus = delstate->status + ideltid->id;
8206 : 538213 : ItemPointer htid = &ideltid->tid;
8207 : : OffsetNumber offnum;
8208 : :
8209 : : /*
8210 : : * Read buffer, and perform required extra steps each time a new block
8211 : : * is encountered. Avoid refetching if it's the same block as the one
8212 : : * from the last htid.
8213 : : */
1763 8214 [ + + + + ]: 1070835 : if (blkno == InvalidBlockNumber ||
8215 : 532622 : ItemPointerGetBlockNumber(htid) != blkno)
8216 : : {
8217 : : /*
8218 : : * Consider giving up early for bottom-up index deletion caller
8219 : : * first. (Only prefetch next-next block afterwards, when it
8220 : : * becomes clear that we're at least going to access the next
8221 : : * block in line.)
8222 : : *
8223 : : * Sometimes the first block frees so much space for bottom-up
8224 : : * caller that the deletion process can end without accessing any
8225 : : * more blocks. It is usually necessary to access 2 or 3 blocks
8226 : : * per bottom-up deletion operation, though.
8227 : : */
1749 8228 [ + + ]: 15338 : if (delstate->bottomup)
8229 : : {
8230 : : /*
8231 : : * We often allow caller to delete a few additional items
8232 : : * whose entries we reached after the point that space target
8233 : : * from caller was satisfied. The cost of accessing the page
8234 : : * was already paid at that point, so it made sense to finish
8235 : : * it off. When that happened, we finalize everything here
8236 : : * (by finishing off the whole bottom-up deletion operation
8237 : : * without needlessly paying the cost of accessing any more
8238 : : * blocks).
8239 : : */
8240 [ + + ]: 4244 : if (bottomup_final_block)
8241 : 133 : break;
8242 : :
8243 : : /*
8244 : : * Give up when we didn't enable our caller to free any
8245 : : * additional space as a result of processing the page that we
8246 : : * just finished up with. This rule is the main way in which
8247 : : * we keep the cost of bottom-up deletion under control.
8248 : : */
8249 [ + + + + ]: 4111 : if (nblocksaccessed >= 1 && actualfreespace == lastfreespace)
8250 : 1787 : break;
8251 : 2324 : lastfreespace = actualfreespace; /* for next time */
8252 : :
8253 : : /*
8254 : : * Deletion operation (which is bottom-up) will definitely
8255 : : * access the next block in line. Prepare for that now.
8256 : : *
8257 : : * Decay target free space so that we don't hang on for too
8258 : : * long with a marginal case. (Space target is only truly
8259 : : * helpful when it allows us to recognize that we don't need
8260 : : * to access more than 1 or 2 blocks to satisfy caller due to
8261 : : * agreeable workload characteristics.)
8262 : : *
8263 : : * We are a bit more patient when we encounter contiguous
8264 : : * blocks, though: these are treated as favorable blocks. The
8265 : : * decay process is only applied when the next block in line
8266 : : * is not a favorable/contiguous block. This is not an
8267 : : * exception to the general rule; we still insist on finding
8268 : : * at least one deletable item per block accessed. See
8269 : : * bottomup_nblocksfavorable() for full details of the theory
8270 : : * behind favorable blocks and heap block locality in general.
8271 : : *
8272 : : * Note: The first block in line is always treated as a
8273 : : * favorable block, so the earliest possible point that the
8274 : : * decay can be applied is just before we access the second
8275 : : * block in line. The Assert() verifies this for us.
8276 : : */
8277 [ + + - + ]: 2324 : Assert(nblocksaccessed > 0 || nblocksfavorable > 0);
8278 [ + + ]: 2324 : if (nblocksfavorable > 0)
8279 : 2082 : nblocksfavorable--;
8280 : : else
8281 : 242 : curtargetfreespace /= 2;
8282 : : }
8283 : :
8284 : : /* release old buffer */
8285 [ + + ]: 13418 : if (BufferIsValid(buf))
8286 : 7827 : UnlockReleaseBuffer(buf);
8287 : :
8288 : 13418 : blkno = ItemPointerGetBlockNumber(htid);
1763 8289 : 13418 : buf = ReadBuffer(rel, blkno);
1749 8290 : 13418 : nblocksaccessed++;
8291 [ + + - + ]: 13418 : Assert(!delstate->bottomup ||
8292 : : nblocksaccessed <= BOTTOMUP_MAX_NBLOCKS);
8293 : :
8294 : : #ifdef USE_PREFETCH
8295 : :
8296 : : /*
8297 : : * To maintain the prefetch distance, prefetch one more page for
8298 : : * each page we read.
8299 : : */
8300 : 13418 : index_delete_prefetch_buffer(rel, &prefetch_state, 1);
8301 : : #endif
8302 : :
1763 8303 : 13418 : LockBuffer(buf, BUFFER_LOCK_SHARE);
8304 : :
8305 : 13418 : page = BufferGetPage(buf);
8306 : 13418 : maxoff = PageGetMaxOffsetNumber(page);
8307 : : }
8308 : :
8309 : : /*
8310 : : * In passing, detect index corruption involving an index page with a
8311 : : * TID that points to a location in the heap that couldn't possibly be
8312 : : * correct. We only do this with actual TIDs from caller's index page
8313 : : * (not items reached by traversing through a HOT chain).
8314 : : */
1454 8315 : 536293 : index_delete_check_htid(delstate, page, maxoff, htid, istatus);
8316 : :
1749 8317 [ + + ]: 536293 : if (istatus->knowndeletable)
8318 [ + - - + ]: 134953 : Assert(!delstate->bottomup && !istatus->promising);
8319 : : else
8320 : : {
8321 : 401340 : ItemPointerData tmp = *htid;
8322 : : HeapTupleData heapTuple;
8323 : :
8324 : : /* Are any tuples from this HOT chain non-vacuumable? */
8325 [ + + ]: 401340 : if (heap_hot_search_buffer(&tmp, rel, buf, &SnapshotNonVacuumable,
8326 : : &heapTuple, NULL, true))
8327 : 242320 : continue; /* can't delete entry */
8328 : :
8329 : : /* Caller will delete, since whole HOT chain is vacuumable */
8330 : 159020 : istatus->knowndeletable = true;
8331 : :
8332 : : /* Maintain index free space info for bottom-up deletion case */
8333 [ + + ]: 159020 : if (delstate->bottomup)
8334 : : {
8335 [ - + ]: 7930 : Assert(istatus->freespace > 0);
8336 : 7930 : actualfreespace += istatus->freespace;
8337 [ + + ]: 7930 : if (actualfreespace >= curtargetfreespace)
8338 : 2040 : bottomup_final_block = true;
8339 : : }
8340 : : }
8341 : :
8342 : : /*
8343 : : * Maintain snapshotConflictHorizon value for deletion operation as a
8344 : : * whole by advancing current value using heap tuple headers. This is
8345 : : * loosely based on the logic for pruning a HOT chain.
8346 : : */
1763 8347 : 293973 : offnum = ItemPointerGetOffsetNumber(htid);
8348 : 293973 : priorXmax = InvalidTransactionId; /* cannot check first XMIN */
8349 : : for (;;)
2408 andres@anarazel.de 8350 : 20829 : {
8351 : : ItemId lp;
8352 : : HeapTupleHeader htup;
8353 : :
8354 : : /* Sanity check (pure paranoia) */
1497 pg@bowt.ie 8355 [ - + ]: 314802 : if (offnum < FirstOffsetNumber)
1497 pg@bowt.ie 8356 :UBC 0 : break;
8357 : :
8358 : : /*
8359 : : * An offset past the end of page's line pointer array is possible
8360 : : * when the array was truncated
8361 : : */
1497 pg@bowt.ie 8362 [ - + ]:CBC 314802 : if (offnum > maxoff)
1763 pg@bowt.ie 8363 :UBC 0 : break;
8364 : :
1763 pg@bowt.ie 8365 :CBC 314802 : lp = PageGetItemId(page, offnum);
8366 [ + + ]: 314802 : if (ItemIdIsRedirected(lp))
8367 : : {
8368 : 9313 : offnum = ItemIdGetRedirect(lp);
8369 : 9313 : continue;
8370 : : }
8371 : :
8372 : : /*
8373 : : * We'll often encounter LP_DEAD line pointers (especially with an
8374 : : * entry marked knowndeletable by our caller up front). No heap
8375 : : * tuple headers get examined for an htid that leads us to an
8376 : : * LP_DEAD item. This is okay because the earlier pruning
8377 : : * operation that made the line pointer LP_DEAD in the first place
8378 : : * must have considered the original tuple header as part of
8379 : : * generating its own snapshotConflictHorizon value.
8380 : : *
8381 : : * Relying on XLOG_HEAP2_PRUNE_VACUUM_SCAN records like this is
8382 : : * the same strategy that index vacuuming uses in all cases. Index
8383 : : * VACUUM WAL records don't even have a snapshotConflictHorizon
8384 : : * field of their own for this reason.
8385 : : */
8386 [ + + ]: 305489 : if (!ItemIdIsNormal(lp))
8387 : 193005 : break;
8388 : :
8389 : 112484 : htup = (HeapTupleHeader) PageGetItem(page, lp);
8390 : :
8391 : : /*
8392 : : * Check the tuple XMIN against prior XMAX, if any
8393 : : */
8394 [ + + - + ]: 124000 : if (TransactionIdIsValid(priorXmax) &&
8395 : 11516 : !TransactionIdEquals(HeapTupleHeaderGetXmin(htup), priorXmax))
1763 pg@bowt.ie 8396 :UBC 0 : break;
8397 : :
1076 pg@bowt.ie 8398 :CBC 112484 : HeapTupleHeaderAdvanceConflictHorizon(htup,
8399 : : &snapshotConflictHorizon);
8400 : :
8401 : : /*
8402 : : * If the tuple is not HOT-updated, then we are at the end of this
8403 : : * HOT-chain. No need to visit later tuples from the same update
8404 : : * chain (they get their own index entries) -- just move on to
8405 : : * next htid from index AM caller.
8406 : : */
1763 8407 [ + + ]: 112484 : if (!HeapTupleHeaderIsHotUpdated(htup))
8408 : 100968 : break;
8409 : :
8410 : : /* Advance to next HOT chain member */
8411 [ - + ]: 11516 : Assert(ItemPointerGetBlockNumber(&htup->t_ctid) == blkno);
8412 : 11516 : offnum = ItemPointerGetOffsetNumber(&htup->t_ctid);
8413 : 11516 : priorXmax = HeapTupleHeaderGetUpdateXid(htup);
8414 : : }
8415 : :
8416 : : /* Enable further/final shrinking of deltids for caller */
1749 8417 : 293973 : finalndeltids = i + 1;
8418 : : }
8419 : :
8420 : 5591 : UnlockReleaseBuffer(buf);
8421 : :
8422 : : /*
8423 : : * Shrink deltids array to exclude non-deletable entries at the end. This
8424 : : * is not just a minor optimization. Final deltids array size might be
8425 : : * zero for a bottom-up caller. Index AM is explicitly allowed to rely on
8426 : : * ndeltids being zero in all cases with zero total deletable entries.
8427 : : */
8428 [ + + - + ]: 5591 : Assert(finalndeltids > 0 || delstate->bottomup);
8429 : 5591 : delstate->ndeltids = finalndeltids;
8430 : :
1076 8431 : 5591 : return snapshotConflictHorizon;
8432 : : }
8433 : :
8434 : : /*
8435 : : * Specialized inlineable comparison function for index_delete_sort()
8436 : : */
8437 : : static inline int
1749 8438 : 12583535 : index_delete_sort_cmp(TM_IndexDelete *deltid1, TM_IndexDelete *deltid2)
8439 : : {
8440 : 12583535 : ItemPointer tid1 = &deltid1->tid;
8441 : 12583535 : ItemPointer tid2 = &deltid2->tid;
8442 : :
8443 : : {
8444 : 12583535 : BlockNumber blk1 = ItemPointerGetBlockNumber(tid1);
8445 : 12583535 : BlockNumber blk2 = ItemPointerGetBlockNumber(tid2);
8446 : :
8447 [ + + ]: 12583535 : if (blk1 != blk2)
8448 [ + + ]: 5125942 : return (blk1 < blk2) ? -1 : 1;
8449 : : }
8450 : : {
8451 : 7457593 : OffsetNumber pos1 = ItemPointerGetOffsetNumber(tid1);
8452 : 7457593 : OffsetNumber pos2 = ItemPointerGetOffsetNumber(tid2);
8453 : :
8454 [ + - ]: 7457593 : if (pos1 != pos2)
8455 [ + + ]: 7457593 : return (pos1 < pos2) ? -1 : 1;
8456 : : }
8457 : :
1460 pg@bowt.ie 8458 :UBC 0 : Assert(false);
8459 : :
8460 : : return 0;
8461 : : }
8462 : :
8463 : : /*
8464 : : * Sort deltids array from delstate by TID. This prepares it for further
8465 : : * processing by heap_index_delete_tuples().
8466 : : *
8467 : : * This operation becomes a noticeable consumer of CPU cycles with some
8468 : : * workloads, so we go to the trouble of specialization/micro optimization.
8469 : : * We use shellsort for this because it's easy to specialize, compiles to
8470 : : * relatively few instructions, and is adaptive to presorted inputs/subsets
8471 : : * (which are typical here).
8472 : : */
8473 : : static void
1749 pg@bowt.ie 8474 :CBC 5591 : index_delete_sort(TM_IndexDeleteOp *delstate)
8475 : : {
8476 : 5591 : TM_IndexDelete *deltids = delstate->deltids;
8477 : 5591 : int ndeltids = delstate->ndeltids;
8478 : :
8479 : : /*
8480 : : * Shellsort gap sequence (taken from Sedgewick-Incerpi paper).
8481 : : *
8482 : : * This implementation is fast with array sizes up to ~4500. This covers
8483 : : * all supported BLCKSZ values.
8484 : : */
8485 : 5591 : const int gaps[9] = {1968, 861, 336, 112, 48, 21, 7, 3, 1};
8486 : :
8487 : : /* Think carefully before changing anything here -- keep swaps cheap */
8488 : : StaticAssertDecl(sizeof(TM_IndexDelete) <= 8,
8489 : : "element size exceeds 8 bytes");
8490 : :
8491 [ + + ]: 55910 : for (int g = 0; g < lengthof(gaps); g++)
8492 : : {
356 dgustafsson@postgres 8493 [ + + ]: 7498048 : for (int hi = gaps[g], i = hi; i < ndeltids; i++)
8494 : : {
1749 pg@bowt.ie 8495 : 7447729 : TM_IndexDelete d = deltids[i];
8496 : 7447729 : int j = i;
8497 : :
8498 [ + + + + ]: 12946548 : while (j >= hi && index_delete_sort_cmp(&deltids[j - hi], &d) >= 0)
8499 : : {
8500 : 5498819 : deltids[j] = deltids[j - hi];
8501 : 5498819 : j -= hi;
8502 : : }
8503 : 7447729 : deltids[j] = d;
8504 : : }
8505 : : }
8506 : 5591 : }
8507 : :
8508 : : /*
8509 : : * Returns how many blocks should be considered favorable/contiguous for a
8510 : : * bottom-up index deletion pass. This is a number of heap blocks that starts
8511 : : * from and includes the first block in line.
8512 : : *
8513 : : * There is always at least one favorable block during bottom-up index
8514 : : * deletion. In the worst case (i.e. with totally random heap blocks) the
8515 : : * first block in line (the only favorable block) can be thought of as a
8516 : : * degenerate array of contiguous blocks that consists of a single block.
8517 : : * heap_index_delete_tuples() will expect this.
8518 : : *
8519 : : * Caller passes blockgroups, a description of the final order that deltids
8520 : : * will be sorted in for heap_index_delete_tuples() bottom-up index deletion
8521 : : * processing. Note that deltids need not actually be sorted just yet (caller
8522 : : * only passes deltids to us so that we can interpret blockgroups).
8523 : : *
8524 : : * You might guess that the existence of contiguous blocks cannot matter much,
8525 : : * since in general the main factor that determines which blocks we visit is
8526 : : * the number of promising TIDs, which is a fixed hint from the index AM.
8527 : : * We're not really targeting the general case, though -- the actual goal is
8528 : : * to adapt our behavior to a wide variety of naturally occurring conditions.
8529 : : * The effects of most of the heuristics we apply are only noticeable in the
8530 : : * aggregate, over time and across many _related_ bottom-up index deletion
8531 : : * passes.
8532 : : *
8533 : : * Deeming certain blocks favorable allows heapam to recognize and adapt to
8534 : : * workloads where heap blocks visited during bottom-up index deletion can be
8535 : : * accessed contiguously, in the sense that each newly visited block is the
8536 : : * neighbor of the block that bottom-up deletion just finished processing (or
8537 : : * close enough to it). It will likely be cheaper to access more favorable
8538 : : * blocks sooner rather than later (e.g. in this pass, not across a series of
8539 : : * related bottom-up passes). Either way it is probably only a matter of time
8540 : : * (or a matter of further correlated version churn) before all blocks that
8541 : : * appear together as a single large batch of favorable blocks get accessed by
8542 : : * _some_ bottom-up pass. Large batches of favorable blocks tend to either
8543 : : * appear almost constantly or not even once (it all depends on per-index
8544 : : * workload characteristics).
8545 : : *
8546 : : * Note that the blockgroups sort order applies a power-of-two bucketing
8547 : : * scheme that creates opportunities for contiguous groups of blocks to get
8548 : : * batched together, at least with workloads that are naturally amenable to
8549 : : * being driven by heap block locality. This doesn't just enhance the spatial
8550 : : * locality of bottom-up heap block processing in the obvious way. It also
8551 : : * enables temporal locality of access, since sorting by heap block number
8552 : : * naturally tends to make the bottom-up processing order deterministic.
8553 : : *
8554 : : * Consider the following example to get a sense of how temporal locality
8555 : : * might matter: There is a heap relation with several indexes, each of which
8556 : : * is low to medium cardinality. It is subject to constant non-HOT updates.
8557 : : * The updates are skewed (in one part of the primary key, perhaps). None of
8558 : : * the indexes are logically modified by the UPDATE statements (if they were
8559 : : * then bottom-up index deletion would not be triggered in the first place).
8560 : : * Naturally, each new round of index tuples (for each heap tuple that gets a
8561 : : * heap_update() call) will have the same heap TID in each and every index.
8562 : : * Since these indexes are low cardinality and never get logically modified,
8563 : : * heapam processing during bottom-up deletion passes will access heap blocks
8564 : : * in approximately sequential order. Temporal locality of access occurs due
8565 : : * to bottom-up deletion passes behaving very similarly across each of the
8566 : : * indexes at any given moment. This keeps the number of buffer misses needed
8567 : : * to visit heap blocks to a minimum.
8568 : : */
8569 : : static int
8570 : 1920 : bottomup_nblocksfavorable(IndexDeleteCounts *blockgroups, int nblockgroups,
8571 : : TM_IndexDelete *deltids)
8572 : : {
8573 : 1920 : int64 lastblock = -1;
8574 : 1920 : int nblocksfavorable = 0;
8575 : :
8576 [ - + ]: 1920 : Assert(nblockgroups >= 1);
8577 [ - + ]: 1920 : Assert(nblockgroups <= BOTTOMUP_MAX_NBLOCKS);
8578 : :
8579 : : /*
8580 : : * We tolerate heap blocks that will be accessed only slightly out of
8581 : : * physical order. Small blips occur when a pair of almost-contiguous
8582 : : * blocks happen to fall into different buckets (perhaps due only to a
8583 : : * small difference in npromisingtids that the bucketing scheme didn't
8584 : : * quite manage to ignore). We effectively ignore these blips by applying
8585 : : * a small tolerance. The precise tolerance we use is a little arbitrary,
8586 : : * but it works well enough in practice.
8587 : : */
8588 [ + + ]: 6207 : for (int b = 0; b < nblockgroups; b++)
8589 : : {
8590 : 5936 : IndexDeleteCounts *group = blockgroups + b;
8591 : 5936 : TM_IndexDelete *firstdtid = deltids + group->ifirsttid;
8592 : 5936 : BlockNumber block = ItemPointerGetBlockNumber(&firstdtid->tid);
8593 : :
8594 [ + + ]: 5936 : if (lastblock != -1 &&
8595 [ + + ]: 4016 : ((int64) block < lastblock - BOTTOMUP_TOLERANCE_NBLOCKS ||
8596 [ + + ]: 3473 : (int64) block > lastblock + BOTTOMUP_TOLERANCE_NBLOCKS))
8597 : : break;
8598 : :
8599 : 4287 : nblocksfavorable++;
8600 : 4287 : lastblock = block;
8601 : : }
8602 : :
8603 : : /* Always indicate that there is at least 1 favorable block */
8604 [ - + ]: 1920 : Assert(nblocksfavorable >= 1);
8605 : :
8606 : 1920 : return nblocksfavorable;
8607 : : }
8608 : :
8609 : : /*
8610 : : * qsort comparison function for bottomup_sort_and_shrink()
8611 : : */
8612 : : static int
8613 : 195119 : bottomup_sort_and_shrink_cmp(const void *arg1, const void *arg2)
8614 : : {
8615 : 195119 : const IndexDeleteCounts *group1 = (const IndexDeleteCounts *) arg1;
8616 : 195119 : const IndexDeleteCounts *group2 = (const IndexDeleteCounts *) arg2;
8617 : :
8618 : : /*
8619 : : * Most significant field is npromisingtids (which we invert the order of
8620 : : * so as to sort in desc order).
8621 : : *
8622 : : * Caller should have already normalized npromisingtids fields into
8623 : : * power-of-two values (buckets).
8624 : : */
8625 [ + + ]: 195119 : if (group1->npromisingtids > group2->npromisingtids)
8626 : 8434 : return -1;
8627 [ + + ]: 186685 : if (group1->npromisingtids < group2->npromisingtids)
8628 : 10482 : return 1;
8629 : :
8630 : : /*
8631 : : * Tiebreak: desc ntids sort order.
8632 : : *
8633 : : * We cannot expect power-of-two values for ntids fields. We should
8634 : : * behave as if they were already rounded up for us instead.
8635 : : */
8636 [ + + ]: 176203 : if (group1->ntids != group2->ntids)
8637 : : {
8638 : 122991 : uint32 ntids1 = pg_nextpower2_32((uint32) group1->ntids);
8639 : 122991 : uint32 ntids2 = pg_nextpower2_32((uint32) group2->ntids);
8640 : :
8641 [ + + ]: 122991 : if (ntids1 > ntids2)
8642 : 19457 : return -1;
8643 [ + + ]: 103534 : if (ntids1 < ntids2)
8644 : 23626 : return 1;
8645 : : }
8646 : :
8647 : : /*
8648 : : * Tiebreak: asc offset-into-deltids-for-block (offset to first TID for
8649 : : * block in deltids array) order.
8650 : : *
8651 : : * This is equivalent to sorting in ascending heap block number order
8652 : : * (among otherwise equal subsets of the array). This approach allows us
8653 : : * to avoid accessing the out-of-line TID. (We rely on the assumption
8654 : : * that the deltids array was sorted in ascending heap TID order when
8655 : : * these offsets to the first TID from each heap block group were formed.)
8656 : : */
8657 [ + + ]: 133120 : if (group1->ifirsttid > group2->ifirsttid)
8658 : 65727 : return 1;
8659 [ + - ]: 67393 : if (group1->ifirsttid < group2->ifirsttid)
8660 : 67393 : return -1;
8661 : :
1749 pg@bowt.ie 8662 :UBC 0 : pg_unreachable();
8663 : :
8664 : : return 0;
8665 : : }
8666 : :
8667 : : /*
8668 : : * heap_index_delete_tuples() helper function for bottom-up deletion callers.
8669 : : *
8670 : : * Sorts deltids array in the order needed for useful processing by bottom-up
8671 : : * deletion. The array should already be sorted in TID order when we're
8672 : : * called. The sort process groups heap TIDs from deltids into heap block
8673 : : * groupings. Earlier/more-promising groups/blocks are usually those that are
8674 : : * known to have the most "promising" TIDs.
8675 : : *
8676 : : * Sets new size of deltids array (ndeltids) in state. deltids will only have
8677 : : * TIDs from the BOTTOMUP_MAX_NBLOCKS most promising heap blocks when we
8678 : : * return. This often means that deltids will be shrunk to a small fraction
8679 : : * of its original size (we eliminate many heap blocks from consideration for
8680 : : * caller up front).
8681 : : *
8682 : : * Returns the number of "favorable" blocks. See bottomup_nblocksfavorable()
8683 : : * for a definition and full details.
8684 : : */
8685 : : static int
1749 pg@bowt.ie 8686 :CBC 1920 : bottomup_sort_and_shrink(TM_IndexDeleteOp *delstate)
8687 : : {
8688 : : IndexDeleteCounts *blockgroups;
8689 : : TM_IndexDelete *reordereddeltids;
8690 : 1920 : BlockNumber curblock = InvalidBlockNumber;
8691 : 1920 : int nblockgroups = 0;
8692 : 1920 : int ncopied = 0;
8693 : 1920 : int nblocksfavorable = 0;
8694 : :
8695 [ - + ]: 1920 : Assert(delstate->bottomup);
8696 [ - + ]: 1920 : Assert(delstate->ndeltids > 0);
8697 : :
8698 : : /* Calculate per-heap-block count of TIDs */
8699 : 1920 : blockgroups = palloc(sizeof(IndexDeleteCounts) * delstate->ndeltids);
8700 [ + + ]: 927584 : for (int i = 0; i < delstate->ndeltids; i++)
8701 : : {
8702 : 925664 : TM_IndexDelete *ideltid = &delstate->deltids[i];
8703 : 925664 : TM_IndexStatus *istatus = delstate->status + ideltid->id;
8704 : 925664 : ItemPointer htid = &ideltid->tid;
8705 : 925664 : bool promising = istatus->promising;
8706 : :
8707 [ + + ]: 925664 : if (curblock != ItemPointerGetBlockNumber(htid))
8708 : : {
8709 : : /* New block group */
8710 : 37709 : nblockgroups++;
8711 : :
8712 [ + + - + ]: 37709 : Assert(curblock < ItemPointerGetBlockNumber(htid) ||
8713 : : !BlockNumberIsValid(curblock));
8714 : :
8715 : 37709 : curblock = ItemPointerGetBlockNumber(htid);
8716 : 37709 : blockgroups[nblockgroups - 1].ifirsttid = i;
8717 : 37709 : blockgroups[nblockgroups - 1].ntids = 1;
8718 : 37709 : blockgroups[nblockgroups - 1].npromisingtids = 0;
8719 : : }
8720 : : else
8721 : : {
8722 : 887955 : blockgroups[nblockgroups - 1].ntids++;
8723 : : }
8724 : :
8725 [ + + ]: 925664 : if (promising)
8726 : 118954 : blockgroups[nblockgroups - 1].npromisingtids++;
8727 : : }
8728 : :
8729 : : /*
8730 : : * We're about ready to sort block groups to determine the optimal order
8731 : : * for visiting heap blocks. But before we do, round the number of
8732 : : * promising tuples for each block group up to the next power-of-two,
8733 : : * unless it is very low (less than 4), in which case we round up to 4.
8734 : : * npromisingtids is far too noisy to trust when choosing between a pair
8735 : : * of block groups that both have very low values.
8736 : : *
8737 : : * This scheme divides heap blocks/block groups into buckets. Each bucket
8738 : : * contains blocks that have _approximately_ the same number of promising
8739 : : * TIDs as each other. The goal is to ignore relatively small differences
8740 : : * in the total number of promising entries, so that the whole process can
8741 : : * give a little weight to heapam factors (like heap block locality)
8742 : : * instead. This isn't a trade-off, really -- we have nothing to lose. It
8743 : : * would be foolish to interpret small differences in npromisingtids
8744 : : * values as anything more than noise.
8745 : : *
8746 : : * We tiebreak on nhtids when sorting block group subsets that have the
8747 : : * same npromisingtids, but this has the same issues as npromisingtids,
8748 : : * and so nhtids is subject to the same power-of-two bucketing scheme. The
8749 : : * only reason that we don't fix nhtids in the same way here too is that
8750 : : * we'll need accurate nhtids values after the sort. We handle nhtids
8751 : : * bucketization dynamically instead (in the sort comparator).
8752 : : *
8753 : : * See bottomup_nblocksfavorable() for a full explanation of when and how
8754 : : * heap locality/favorable blocks can significantly influence when and how
8755 : : * heap blocks are accessed.
8756 : : */
8757 [ + + ]: 39629 : for (int b = 0; b < nblockgroups; b++)
8758 : : {
8759 : 37709 : IndexDeleteCounts *group = blockgroups + b;
8760 : :
8761 : : /* Better off falling back on nhtids with low npromisingtids */
8762 [ + + ]: 37709 : if (group->npromisingtids <= 4)
8763 : 32396 : group->npromisingtids = 4;
8764 : : else
8765 : 5313 : group->npromisingtids =
8766 : 5313 : pg_nextpower2_32((uint32) group->npromisingtids);
8767 : : }
8768 : :
8769 : : /* Sort groups and rearrange caller's deltids array */
8770 : 1920 : qsort(blockgroups, nblockgroups, sizeof(IndexDeleteCounts),
8771 : : bottomup_sort_and_shrink_cmp);
8772 : 1920 : reordereddeltids = palloc(delstate->ndeltids * sizeof(TM_IndexDelete));
8773 : :
8774 : 1920 : nblockgroups = Min(BOTTOMUP_MAX_NBLOCKS, nblockgroups);
8775 : : /* Determine number of favorable blocks at the start of final deltids */
8776 : 1920 : nblocksfavorable = bottomup_nblocksfavorable(blockgroups, nblockgroups,
8777 : : delstate->deltids);
8778 : :
8779 [ + + ]: 12830 : for (int b = 0; b < nblockgroups; b++)
8780 : : {
8781 : 10910 : IndexDeleteCounts *group = blockgroups + b;
8782 : 10910 : TM_IndexDelete *firstdtid = delstate->deltids + group->ifirsttid;
8783 : :
8784 : 10910 : memcpy(reordereddeltids + ncopied, firstdtid,
8785 : 10910 : sizeof(TM_IndexDelete) * group->ntids);
8786 : 10910 : ncopied += group->ntids;
8787 : : }
8788 : :
8789 : : /* Copy final grouped and sorted TIDs back into start of caller's array */
8790 : 1920 : memcpy(delstate->deltids, reordereddeltids,
8791 : : sizeof(TM_IndexDelete) * ncopied);
8792 : 1920 : delstate->ndeltids = ncopied;
8793 : :
8794 : 1920 : pfree(reordereddeltids);
8795 : 1920 : pfree(blockgroups);
8796 : :
8797 : 1920 : return nblocksfavorable;
8798 : : }
8799 : :
8800 : : /*
8801 : : * Perform XLogInsert for a heap-visible operation. 'block' is the block
8802 : : * being marked all-visible, and vm_buffer is the buffer containing the
8803 : : * corresponding visibility map block. Both should have already been modified
8804 : : * and dirtied.
8805 : : *
8806 : : * snapshotConflictHorizon comes from the largest xmin on the page being
8807 : : * marked all-visible. REDO routine uses it to generate recovery conflicts.
8808 : : *
8809 : : * If checksums or wal_log_hints are enabled, we may also generate a full-page
8810 : : * image of heap_buffer. Otherwise, we optimize away the FPI (by specifying
8811 : : * REGBUF_NO_IMAGE for the heap buffer), in which case the caller should *not*
8812 : : * update the heap page's LSN.
8813 : : */
8814 : : XLogRecPtr
941 andres@anarazel.de 8815 : 36143 : log_heap_visible(Relation rel, Buffer heap_buffer, Buffer vm_buffer,
8816 : : TransactionId snapshotConflictHorizon, uint8 vmflags)
8817 : : {
8818 : : xl_heap_visible xlrec;
8819 : : XLogRecPtr recptr;
8820 : : uint8 flags;
8821 : :
4603 simon@2ndQuadrant.co 8822 [ - + ]: 36143 : Assert(BufferIsValid(heap_buffer));
8823 [ - + ]: 36143 : Assert(BufferIsValid(vm_buffer));
8824 : :
1076 pg@bowt.ie 8825 : 36143 : xlrec.snapshotConflictHorizon = snapshotConflictHorizon;
3528 rhaas@postgresql.org 8826 : 36143 : xlrec.flags = vmflags;
940 andres@anarazel.de 8827 [ + + + - : 36143 : if (RelationIsAccessibleInLogicalDecoding(rel))
- + - - -
- + + - +
- - - - -
- ]
8828 : 48 : xlrec.flags |= VISIBILITYMAP_XLOG_CATALOG_REL;
3995 heikki.linnakangas@i 8829 : 36143 : XLogBeginInsert();
259 peter@eisentraut.org 8830 : 36143 : XLogRegisterData(&xlrec, SizeOfHeapVisible);
8831 : :
3995 heikki.linnakangas@i 8832 : 36143 : XLogRegisterBuffer(0, vm_buffer, 0);
8833 : :
8834 : 36143 : flags = REGBUF_STANDARD;
8835 [ + + + - ]: 36143 : if (!XLogHintBitIsNeeded())
8836 : 3150 : flags |= REGBUF_NO_IMAGE;
8837 : 36143 : XLogRegisterBuffer(1, heap_buffer, flags);
8838 : :
8839 : 36143 : recptr = XLogInsert(RM_HEAP2_ID, XLOG_HEAP2_VISIBLE);
8840 : :
5243 rhaas@postgresql.org 8841 : 36143 : return recptr;
8842 : : }
8843 : :
8844 : : /*
8845 : : * Perform XLogInsert for a heap-update operation. Caller must already
8846 : : * have modified the buffer(s) and marked them dirty.
8847 : : */
8848 : : static XLogRecPtr
4661 alvherre@alvh.no-ip. 8849 : 292772 : log_heap_update(Relation reln, Buffer oldbuf,
8850 : : Buffer newbuf, HeapTuple oldtup, HeapTuple newtup,
8851 : : HeapTuple old_key_tuple,
8852 : : bool all_visible_cleared, bool new_all_visible_cleared)
8853 : : {
8854 : : xl_heap_update xlrec;
8855 : : xl_heap_header xlhdr;
8856 : : xl_heap_header xlhdr_idx;
8857 : : uint8 info;
8858 : : uint16 prefix_suffix[2];
4248 heikki.linnakangas@i 8859 : 292772 : uint16 prefixlen = 0,
8860 : 292772 : suffixlen = 0;
8861 : : XLogRecPtr recptr;
3478 kgrittn@postgresql.o 8862 : 292772 : Page page = BufferGetPage(newbuf);
4340 rhaas@postgresql.org 8863 [ + + + - : 292772 : bool need_tuple_data = RelationIsLogicallyLogged(reln);
- + - - -
- + - +
+ ]
8864 : : bool init;
8865 : : int bufflags;
8866 : :
8867 : : /* Caller should not call me on a non-WAL-logged relation */
5433 8868 [ + - + + : 292772 : Assert(RelationNeedsWAL(reln));
+ - - + ]
8869 : :
3995 heikki.linnakangas@i 8870 : 292772 : XLogBeginInsert();
8871 : :
5741 tgl@sss.pgh.pa.us 8872 [ + + ]: 292772 : if (HeapTupleIsHeapOnly(newtup))
6613 8873 : 142125 : info = XLOG_HEAP_HOT_UPDATE;
8874 : : else
8875 : 150647 : info = XLOG_HEAP_UPDATE;
8876 : :
8877 : : /*
8878 : : * If the old and new tuple are on the same page, we only need to log the
8879 : : * parts of the new tuple that were changed. That saves on the amount of
8880 : : * WAL we need to write. Currently, we just count any unchanged bytes in
8881 : : * the beginning and end of the tuple. That's quick to check, and
8882 : : * perfectly covers the common case that only one field is updated.
8883 : : *
8884 : : * We could do this even if the old and new tuple are on different pages,
8885 : : * but only if we don't make a full-page image of the old page, which is
8886 : : * difficult to know in advance. Also, if the old tuple is corrupt for
8887 : : * some reason, it would allow the corruption to propagate the new page,
8888 : : * so it seems best to avoid. Under the general assumption that most
8889 : : * updates tend to create the new tuple version on the same page, there
8890 : : * isn't much to be gained by doing this across pages anyway.
8891 : : *
8892 : : * Skip this if we're taking a full-page image of the new page, as we
8893 : : * don't include the new tuple in the WAL record in that case. Also
8894 : : * disable if wal_level='logical', as logical decoding needs to be able to
8895 : : * read the new tuple in whole from the WAL record alone.
8896 : : */
4248 heikki.linnakangas@i 8897 [ + + + + ]: 292772 : if (oldbuf == newbuf && !need_tuple_data &&
8898 [ + + ]: 142140 : !XLogCheckBufferNeedsBackup(newbuf))
8899 : : {
8900 : 141648 : char *oldp = (char *) oldtup->t_data + oldtup->t_data->t_hoff;
8901 : 141648 : char *newp = (char *) newtup->t_data + newtup->t_data->t_hoff;
8902 : 141648 : int oldlen = oldtup->t_len - oldtup->t_data->t_hoff;
8903 : 141648 : int newlen = newtup->t_len - newtup->t_data->t_hoff;
8904 : :
8905 : : /* Check for common prefix between old and new tuple */
8906 [ + + ]: 11779908 : for (prefixlen = 0; prefixlen < Min(oldlen, newlen); prefixlen++)
8907 : : {
8908 [ + + ]: 11754178 : if (newp[prefixlen] != oldp[prefixlen])
8909 : 115918 : break;
8910 : : }
8911 : :
8912 : : /*
8913 : : * Storing the length of the prefix takes 2 bytes, so we need to save
8914 : : * at least 3 bytes or there's no point.
8915 : : */
8916 [ + + ]: 141648 : if (prefixlen < 3)
8917 : 22089 : prefixlen = 0;
8918 : :
8919 : : /* Same for suffix */
8920 [ + + ]: 4562996 : for (suffixlen = 0; suffixlen < Min(oldlen, newlen) - prefixlen; suffixlen++)
8921 : : {
8922 [ + + ]: 4537007 : if (newp[newlen - suffixlen - 1] != oldp[oldlen - suffixlen - 1])
8923 : 115659 : break;
8924 : : }
8925 [ + + ]: 141648 : if (suffixlen < 3)
8926 : 35442 : suffixlen = 0;
8927 : : }
8928 : :
8929 : : /* Prepare main WAL data chain */
4340 rhaas@postgresql.org 8930 : 292772 : xlrec.flags = 0;
8931 [ + + ]: 292772 : if (all_visible_cleared)
3826 andres@anarazel.de 8932 : 1638 : xlrec.flags |= XLH_UPDATE_OLD_ALL_VISIBLE_CLEARED;
4340 rhaas@postgresql.org 8933 [ + + ]: 292772 : if (new_all_visible_cleared)
3826 andres@anarazel.de 8934 : 1000 : xlrec.flags |= XLH_UPDATE_NEW_ALL_VISIBLE_CLEARED;
4248 heikki.linnakangas@i 8935 [ + + ]: 292772 : if (prefixlen > 0)
3826 andres@anarazel.de 8936 : 119559 : xlrec.flags |= XLH_UPDATE_PREFIX_FROM_OLD;
4248 heikki.linnakangas@i 8937 [ + + ]: 292772 : if (suffixlen > 0)
3826 andres@anarazel.de 8938 : 106206 : xlrec.flags |= XLH_UPDATE_SUFFIX_FROM_OLD;
3995 heikki.linnakangas@i 8939 [ + + ]: 292772 : if (need_tuple_data)
8940 : : {
3826 andres@anarazel.de 8941 : 47013 : xlrec.flags |= XLH_UPDATE_CONTAINS_NEW_TUPLE;
3995 heikki.linnakangas@i 8942 [ + + ]: 47013 : if (old_key_tuple)
8943 : : {
8944 [ + + ]: 145 : if (reln->rd_rel->relreplident == REPLICA_IDENTITY_FULL)
3826 andres@anarazel.de 8945 : 64 : xlrec.flags |= XLH_UPDATE_CONTAINS_OLD_TUPLE;
8946 : : else
8947 : 81 : xlrec.flags |= XLH_UPDATE_CONTAINS_OLD_KEY;
8948 : : }
8949 : : }
8950 : :
8951 : : /* If new tuple is the single and first tuple on page... */
4248 heikki.linnakangas@i 8952 [ + + + + ]: 296107 : if (ItemPointerGetOffsetNumber(&(newtup->t_self)) == FirstOffsetNumber &&
8953 : 3335 : PageGetMaxOffsetNumber(page) == FirstOffsetNumber)
8954 : : {
8955 : 3029 : info |= XLOG_HEAP_INIT_PAGE;
3995 8956 : 3029 : init = true;
8957 : : }
8958 : : else
8959 : 289743 : init = false;
8960 : :
8961 : : /* Prepare WAL data for the old page */
8962 : 292772 : xlrec.old_offnum = ItemPointerGetOffsetNumber(&oldtup->t_self);
8963 : 292772 : xlrec.old_xmax = HeapTupleHeaderGetRawXmax(oldtup->t_data);
8964 : 585544 : xlrec.old_infobits_set = compute_infobits(oldtup->t_data->t_infomask,
8965 : 292772 : oldtup->t_data->t_infomask2);
8966 : :
8967 : : /* Prepare WAL data for the new page */
8968 : 292772 : xlrec.new_offnum = ItemPointerGetOffsetNumber(&newtup->t_self);
8969 : 292772 : xlrec.new_xmax = HeapTupleHeaderGetRawXmax(newtup->t_data);
8970 : :
8971 : 292772 : bufflags = REGBUF_STANDARD;
8972 [ + + ]: 292772 : if (init)
8973 : 3029 : bufflags |= REGBUF_WILL_INIT;
8974 [ + + ]: 292772 : if (need_tuple_data)
8975 : 47013 : bufflags |= REGBUF_KEEP_DATA;
8976 : :
8977 : 292772 : XLogRegisterBuffer(0, newbuf, bufflags);
8978 [ + + ]: 292772 : if (oldbuf != newbuf)
8979 : 138699 : XLogRegisterBuffer(1, oldbuf, REGBUF_STANDARD);
8980 : :
259 peter@eisentraut.org 8981 : 292772 : XLogRegisterData(&xlrec, SizeOfHeapUpdate);
8982 : :
8983 : : /*
8984 : : * Prepare WAL data for the new tuple.
8985 : : */
4248 heikki.linnakangas@i 8986 [ + + + + ]: 292772 : if (prefixlen > 0 || suffixlen > 0)
8987 : : {
8988 [ + + + + ]: 141185 : if (prefixlen > 0 && suffixlen > 0)
8989 : : {
8990 : 84580 : prefix_suffix[0] = prefixlen;
8991 : 84580 : prefix_suffix[1] = suffixlen;
259 peter@eisentraut.org 8992 : 84580 : XLogRegisterBufData(0, &prefix_suffix, sizeof(uint16) * 2);
8993 : : }
4248 heikki.linnakangas@i 8994 [ + + ]: 56605 : else if (prefixlen > 0)
8995 : : {
259 peter@eisentraut.org 8996 : 34979 : XLogRegisterBufData(0, &prefixlen, sizeof(uint16));
8997 : : }
8998 : : else
8999 : : {
9000 : 21626 : XLogRegisterBufData(0, &suffixlen, sizeof(uint16));
9001 : : }
9002 : : }
9003 : :
3995 heikki.linnakangas@i 9004 : 292772 : xlhdr.t_infomask2 = newtup->t_data->t_infomask2;
9005 : 292772 : xlhdr.t_infomask = newtup->t_data->t_infomask;
9006 : 292772 : xlhdr.t_hoff = newtup->t_data->t_hoff;
3902 tgl@sss.pgh.pa.us 9007 [ - + ]: 292772 : Assert(SizeofHeapTupleHeader + prefixlen + suffixlen <= newtup->t_len);
9008 : :
9009 : : /*
9010 : : * PG73FORMAT: write bitmap [+ padding] [+ oid] + data
9011 : : *
9012 : : * The 'data' doesn't include the common prefix or suffix.
9013 : : */
259 peter@eisentraut.org 9014 : 292772 : XLogRegisterBufData(0, &xlhdr, SizeOfHeapHeader);
4248 heikki.linnakangas@i 9015 [ + + ]: 292772 : if (prefixlen == 0)
9016 : : {
3995 9017 : 173213 : XLogRegisterBufData(0,
259 peter@eisentraut.org 9018 : 173213 : (char *) newtup->t_data + SizeofHeapTupleHeader,
3051 tgl@sss.pgh.pa.us 9019 : 173213 : newtup->t_len - SizeofHeapTupleHeader - suffixlen);
9020 : : }
9021 : : else
9022 : : {
9023 : : /*
9024 : : * Have to write the null bitmap and data after the common prefix as
9025 : : * two separate rdata entries.
9026 : : */
9027 : : /* bitmap [+ padding] [+ oid] */
3902 9028 [ + - ]: 119559 : if (newtup->t_data->t_hoff - SizeofHeapTupleHeader > 0)
9029 : : {
3995 heikki.linnakangas@i 9030 : 119559 : XLogRegisterBufData(0,
259 peter@eisentraut.org 9031 : 119559 : (char *) newtup->t_data + SizeofHeapTupleHeader,
3051 tgl@sss.pgh.pa.us 9032 : 119559 : newtup->t_data->t_hoff - SizeofHeapTupleHeader);
9033 : : }
9034 : :
9035 : : /* data after common prefix */
3995 heikki.linnakangas@i 9036 : 119559 : XLogRegisterBufData(0,
259 peter@eisentraut.org 9037 : 119559 : (char *) newtup->t_data + newtup->t_data->t_hoff + prefixlen,
3051 tgl@sss.pgh.pa.us 9038 : 119559 : newtup->t_len - newtup->t_data->t_hoff - prefixlen - suffixlen);
9039 : : }
9040 : :
9041 : : /* We need to log a tuple identity */
3995 heikki.linnakangas@i 9042 [ + + + + ]: 292772 : if (need_tuple_data && old_key_tuple)
9043 : : {
9044 : : /* don't really need this, but its more comfy to decode */
9045 : 145 : xlhdr_idx.t_infomask2 = old_key_tuple->t_data->t_infomask2;
9046 : 145 : xlhdr_idx.t_infomask = old_key_tuple->t_data->t_infomask;
9047 : 145 : xlhdr_idx.t_hoff = old_key_tuple->t_data->t_hoff;
9048 : :
259 peter@eisentraut.org 9049 : 145 : XLogRegisterData(&xlhdr_idx, SizeOfHeapHeader);
9050 : :
9051 : : /* PG73FORMAT: write bitmap [+ padding] [+ oid] + data */
3902 tgl@sss.pgh.pa.us 9052 : 145 : XLogRegisterData((char *) old_key_tuple->t_data + SizeofHeapTupleHeader,
9053 : 145 : old_key_tuple->t_len - SizeofHeapTupleHeader);
9054 : : }
9055 : :
9056 : : /* filtering by origin on a row level is much more efficient */
3232 andres@anarazel.de 9057 : 292772 : XLogSetRecordFlags(XLOG_INCLUDE_ORIGIN);
9058 : :
3995 heikki.linnakangas@i 9059 : 292772 : recptr = XLogInsert(RM_HEAP_ID, info);
9060 : :
7230 neilc@samurai.com 9061 : 292772 : return recptr;
9062 : : }
9063 : :
9064 : : /*
9065 : : * Perform XLogInsert of an XLOG_HEAP2_NEW_CID record
9066 : : *
9067 : : * This is only used in wal_level >= WAL_LEVEL_LOGICAL, and only for catalog
9068 : : * tuples.
9069 : : */
9070 : : static XLogRecPtr
4340 rhaas@postgresql.org 9071 : 23896 : log_heap_new_cid(Relation relation, HeapTuple tup)
9072 : : {
9073 : : xl_heap_new_cid xlrec;
9074 : :
9075 : : XLogRecPtr recptr;
9076 : 23896 : HeapTupleHeader hdr = tup->t_data;
9077 : :
9078 [ - + ]: 23896 : Assert(ItemPointerIsValid(&tup->t_self));
9079 [ - + ]: 23896 : Assert(tup->t_tableOid != InvalidOid);
9080 : :
9081 : 23896 : xlrec.top_xid = GetTopTransactionId();
1210 9082 : 23896 : xlrec.target_locator = relation->rd_locator;
3995 heikki.linnakangas@i 9083 : 23896 : xlrec.target_tid = tup->t_self;
9084 : :
9085 : : /*
9086 : : * If the tuple got inserted & deleted in the same TX we definitely have a
9087 : : * combo CID, set cmin and cmax.
9088 : : */
4340 rhaas@postgresql.org 9089 [ + + ]: 23896 : if (hdr->t_infomask & HEAP_COMBOCID)
9090 : : {
9091 [ - + ]: 1973 : Assert(!(hdr->t_infomask & HEAP_XMAX_INVALID));
4328 9092 [ - + ]: 1973 : Assert(!HeapTupleHeaderXminInvalid(hdr));
4340 9093 : 1973 : xlrec.cmin = HeapTupleHeaderGetCmin(hdr);
9094 : 1973 : xlrec.cmax = HeapTupleHeaderGetCmax(hdr);
9095 : 1973 : xlrec.combocid = HeapTupleHeaderGetRawCommandId(hdr);
9096 : : }
9097 : : /* No combo CID, so only cmin or cmax can be set by this TX */
9098 : : else
9099 : : {
9100 : : /*
9101 : : * Tuple inserted.
9102 : : *
9103 : : * We need to check for LOCK ONLY because multixacts might be
9104 : : * transferred to the new tuple in case of FOR KEY SHARE updates in
9105 : : * which case there will be an xmax, although the tuple just got
9106 : : * inserted.
9107 : : */
9108 [ + + + + ]: 28644 : if (hdr->t_infomask & HEAP_XMAX_INVALID ||
9109 : 6721 : HEAP_XMAX_IS_LOCKED_ONLY(hdr->t_infomask))
9110 : : {
9111 : 15203 : xlrec.cmin = HeapTupleHeaderGetRawCommandId(hdr);
9112 : 15203 : xlrec.cmax = InvalidCommandId;
9113 : : }
9114 : : /* Tuple from a different tx updated or deleted. */
9115 : : else
9116 : : {
9117 : 6720 : xlrec.cmin = InvalidCommandId;
9118 : 6720 : xlrec.cmax = HeapTupleHeaderGetRawCommandId(hdr);
9119 : : }
9120 : 21923 : xlrec.combocid = InvalidCommandId;
9121 : : }
9122 : :
9123 : : /*
9124 : : * Note that we don't need to register the buffer here, because this
9125 : : * operation does not modify the page. The insert/update/delete that
9126 : : * called us certainly did, but that's WAL-logged separately.
9127 : : */
3995 heikki.linnakangas@i 9128 : 23896 : XLogBeginInsert();
259 peter@eisentraut.org 9129 : 23896 : XLogRegisterData(&xlrec, SizeOfHeapNewCid);
9130 : :
9131 : : /* will be looked at irrespective of origin */
9132 : :
3995 heikki.linnakangas@i 9133 : 23896 : recptr = XLogInsert(RM_HEAP2_ID, XLOG_HEAP2_NEW_CID);
9134 : :
4340 rhaas@postgresql.org 9135 : 23896 : return recptr;
9136 : : }
9137 : :
9138 : : /*
9139 : : * Build a heap tuple representing the configured REPLICA IDENTITY to represent
9140 : : * the old tuple in an UPDATE or DELETE.
9141 : : *
9142 : : * Returns NULL if there's no need to log an identity or if there's no suitable
9143 : : * key defined.
9144 : : *
9145 : : * Pass key_required true if any replica identity columns changed value, or if
9146 : : * any of them have any external data. Delete must always pass true.
9147 : : *
9148 : : * *copy is set to true if the returned tuple is a modified copy rather than
9149 : : * the same tuple that was passed in.
9150 : : */
9151 : : static HeapTuple
1352 akapila@postgresql.o 9152 : 1729727 : ExtractReplicaIdentity(Relation relation, HeapTuple tp, bool key_required,
9153 : : bool *copy)
9154 : : {
4340 rhaas@postgresql.org 9155 : 1729727 : TupleDesc desc = RelationGetDescr(relation);
9156 : 1729727 : char replident = relation->rd_rel->relreplident;
9157 : : Bitmapset *idattrs;
9158 : : HeapTuple key_tuple;
9159 : : bool nulls[MaxHeapAttributeNumber];
9160 : : Datum values[MaxHeapAttributeNumber];
9161 : :
9162 : 1729727 : *copy = false;
9163 : :
9164 [ + + + + : 1729727 : if (!RelationIsLogicallyLogged(relation))
- + - - -
- + - +
+ ]
9165 : 1629446 : return NULL;
9166 : :
9167 [ + + ]: 100281 : if (replident == REPLICA_IDENTITY_NOTHING)
9168 : 231 : return NULL;
9169 : :
9170 [ + + ]: 100050 : if (replident == REPLICA_IDENTITY_FULL)
9171 : : {
9172 : : /*
9173 : : * When logging the entire old tuple, it very well could contain
9174 : : * toasted columns. If so, force them to be inlined.
9175 : : */
9176 [ + + ]: 194 : if (HeapTupleHasExternal(tp))
9177 : : {
9178 : 4 : *copy = true;
2248 tgl@sss.pgh.pa.us 9179 : 4 : tp = toast_flatten_tuple(tp, desc);
9180 : : }
4340 rhaas@postgresql.org 9181 : 194 : return tp;
9182 : : }
9183 : :
9184 : : /* if the key isn't required and we're only logging the key, we're done */
1352 akapila@postgresql.o 9185 [ + + ]: 99856 : if (!key_required)
4340 rhaas@postgresql.org 9186 : 46868 : return NULL;
9187 : :
9188 : : /* find out the replica identity columns */
2248 tgl@sss.pgh.pa.us 9189 : 52988 : idattrs = RelationGetIndexAttrBitmap(relation,
9190 : : INDEX_ATTR_BITMAP_IDENTITY_KEY);
9191 : :
9192 : : /*
9193 : : * If there's no defined replica identity columns, treat as !key_required.
9194 : : * (This case should not be reachable from heap_update, since that should
9195 : : * calculate key_required accurately. But heap_delete just passes
9196 : : * constant true for key_required, so we can hit this case in deletes.)
9197 : : */
9198 [ + + ]: 52988 : if (bms_is_empty(idattrs))
9199 : 6021 : return NULL;
9200 : :
9201 : : /*
9202 : : * Construct a new tuple containing only the replica identity columns,
9203 : : * with nulls elsewhere. While we're at it, assert that the replica
9204 : : * identity columns aren't null.
9205 : : */
9206 : 46967 : heap_deform_tuple(tp, desc, values, nulls);
9207 : :
9208 [ + + ]: 150895 : for (int i = 0; i < desc->natts; i++)
9209 : : {
9210 [ + + ]: 103928 : if (bms_is_member(i + 1 - FirstLowInvalidHeapAttributeNumber,
9211 : : idattrs))
9212 [ - + ]: 46979 : Assert(!nulls[i]);
9213 : : else
9214 : 56949 : nulls[i] = true;
9215 : : }
9216 : :
4340 rhaas@postgresql.org 9217 : 46967 : key_tuple = heap_form_tuple(desc, values, nulls);
9218 : 46967 : *copy = true;
9219 : :
2248 tgl@sss.pgh.pa.us 9220 : 46967 : bms_free(idattrs);
9221 : :
9222 : : /*
9223 : : * If the tuple, which by here only contains indexed columns, still has
9224 : : * toasted columns, force them to be inlined. This is somewhat unlikely
9225 : : * since there's limits on the size of indexed columns, so we don't
9226 : : * duplicate toast_flatten_tuple()s functionality in the above loop over
9227 : : * the indexed columns, even if it would be more efficient.
9228 : : */
4340 rhaas@postgresql.org 9229 [ + + ]: 46967 : if (HeapTupleHasExternal(key_tuple))
9230 : : {
4193 bruce@momjian.us 9231 : 4 : HeapTuple oldtup = key_tuple;
9232 : :
2248 tgl@sss.pgh.pa.us 9233 : 4 : key_tuple = toast_flatten_tuple(oldtup, desc);
4340 rhaas@postgresql.org 9234 : 4 : heap_freetuple(oldtup);
9235 : : }
9236 : :
9237 : 46967 : return key_tuple;
9238 : : }
9239 : :
9240 : : /*
9241 : : * HeapCheckForSerializableConflictOut
9242 : : * We are reading a tuple. If it's not visible, there may be a
9243 : : * rw-conflict out with the inserter. Otherwise, if it is visible to us
9244 : : * but has been deleted, there may be a rw-conflict out with the deleter.
9245 : : *
9246 : : * We will determine the top level xid of the writing transaction with which
9247 : : * we may be in conflict, and ask CheckForSerializableConflictOut() to check
9248 : : * for overlap with our own transaction.
9249 : : *
9250 : : * This function should be called just about anywhere in heapam.c where a
9251 : : * tuple has been read. The caller must hold at least a shared lock on the
9252 : : * buffer, because this function might set hint bits on the tuple. There is
9253 : : * currently no known reason to call this function from an index AM.
9254 : : */
9255 : : void
2100 tmunro@postgresql.or 9256 : 30250049 : HeapCheckForSerializableConflictOut(bool visible, Relation relation,
9257 : : HeapTuple tuple, Buffer buffer,
9258 : : Snapshot snapshot)
9259 : : {
9260 : : TransactionId xid;
9261 : : HTSV_Result htsvResult;
9262 : :
9263 [ + + ]: 30250049 : if (!CheckForSerializableConflictOutNeeded(relation, snapshot))
9264 : 30224687 : return;
9265 : :
9266 : : /*
9267 : : * Check to see whether the tuple has been written to by a concurrent
9268 : : * transaction, either to create it not visible to us, or to delete it
9269 : : * while it is visible to us. The "visible" bool indicates whether the
9270 : : * tuple is visible to us, while HeapTupleSatisfiesVacuum checks what else
9271 : : * is going on with it.
9272 : : *
9273 : : * In the event of a concurrently inserted tuple that also happens to have
9274 : : * been concurrently updated (by a separate transaction), the xmin of the
9275 : : * tuple will be used -- not the updater's xid.
9276 : : */
9277 : 25362 : htsvResult = HeapTupleSatisfiesVacuum(tuple, TransactionXmin, buffer);
9278 [ + + + + : 25362 : switch (htsvResult)
- ]
9279 : : {
9280 : 24549 : case HEAPTUPLE_LIVE:
9281 [ + + ]: 24549 : if (visible)
9282 : 24536 : return;
9283 : 13 : xid = HeapTupleHeaderGetXmin(tuple->t_data);
9284 : 13 : break;
9285 : 361 : case HEAPTUPLE_RECENTLY_DEAD:
9286 : : case HEAPTUPLE_DELETE_IN_PROGRESS:
1965 pg@bowt.ie 9287 [ + + ]: 361 : if (visible)
9288 : 285 : xid = HeapTupleHeaderGetUpdateXid(tuple->t_data);
9289 : : else
9290 : 76 : xid = HeapTupleHeaderGetXmin(tuple->t_data);
9291 : :
9292 [ + + ]: 361 : if (TransactionIdPrecedes(xid, TransactionXmin))
9293 : : {
9294 : : /* This is like the HEAPTUPLE_DEAD case */
9295 [ - + ]: 67 : Assert(!visible);
9296 : 67 : return;
9297 : : }
2100 tmunro@postgresql.or 9298 : 294 : break;
9299 : 328 : case HEAPTUPLE_INSERT_IN_PROGRESS:
9300 : 328 : xid = HeapTupleHeaderGetXmin(tuple->t_data);
9301 : 328 : break;
9302 : 124 : case HEAPTUPLE_DEAD:
1965 pg@bowt.ie 9303 [ - + ]: 124 : Assert(!visible);
2100 tmunro@postgresql.or 9304 : 124 : return;
2100 tmunro@postgresql.or 9305 :UBC 0 : default:
9306 : :
9307 : : /*
9308 : : * The only way to get to this default clause is if a new value is
9309 : : * added to the enum type without adding it to this switch
9310 : : * statement. That's a bug, so elog.
9311 : : */
9312 [ # # ]: 0 : elog(ERROR, "unrecognized return value from HeapTupleSatisfiesVacuum: %u", htsvResult);
9313 : :
9314 : : /*
9315 : : * In spite of having all enum values covered and calling elog on
9316 : : * this default, some compilers think this is a code path which
9317 : : * allows xid to be used below without initialization. Silence
9318 : : * that warning.
9319 : : */
9320 : : xid = InvalidTransactionId;
9321 : : }
9322 : :
2100 tmunro@postgresql.or 9323 [ - + ]:CBC 635 : Assert(TransactionIdIsValid(xid));
9324 [ - + ]: 635 : Assert(TransactionIdFollowsOrEquals(xid, TransactionXmin));
9325 : :
9326 : : /*
9327 : : * Find top level xid. Bail out if xid is too early to be a conflict, or
9328 : : * if it's our own xid.
9329 : : */
9330 [ + + ]: 635 : if (TransactionIdEquals(xid, GetTopTransactionIdIfAny()))
9331 : 64 : return;
9332 : 571 : xid = SubTransGetTopmostTransaction(xid);
9333 [ - + ]: 571 : if (TransactionIdPrecedes(xid, TransactionXmin))
2100 tmunro@postgresql.or 9334 :UBC 0 : return;
9335 : :
2100 tmunro@postgresql.or 9336 :CBC 571 : CheckForSerializableConflictOut(relation, xid, snapshot);
9337 : : }
|
