From 84cfddea0ad7b2362f6c47ac68575f2d004edc55 Mon Sep 17 00:00:00 2001 From: Melanie Plageman Date: Thu, 19 Mar 2026 17:05:55 -0400 Subject: [PATCH v45 2/5] Thread flags through begin-scan APIs Add a user-settable flags parameter to the table_beginscan_* wrappers, index_beginscan(), table_index_fetch_begin(), and the table AM callback index_fetch_begin(). This allows users to pass additional context to be used when building the scan descriptors. For index scans, a new uint32 flags field is added to IndexFetchTableData, and the heap AM stores the caller-provided flags there in heapam_index_fetch_begin(). This introduces an extension point for follow-up work to pass per-scan information (such as whether the relation is read-only for the current query) from the executor to the AM layer. Author: Melanie Plageman Reviewed-by: Andres Freund Reviewed-by: Chao Li Discussion: https://postgr.es/m/F5CDD1B5-628C-44A1-9F85-3958C626F6A9%40gmail.com --- contrib/pgrowlocks/pgrowlocks.c | 2 +- src/backend/access/brin/brin.c | 1 + src/backend/access/gin/gininsert.c | 1 + src/backend/access/heap/heapam_handler.c | 9 ++- src/backend/access/index/genam.c | 2 + src/backend/access/index/indexam.c | 6 +- src/backend/access/nbtree/nbtsort.c | 2 +- src/backend/access/table/tableam.c | 19 ++++--- src/backend/commands/constraint.c | 2 +- src/backend/commands/copyto.c | 2 +- src/backend/commands/tablecmds.c | 9 ++- src/backend/commands/typecmds.c | 4 +- src/backend/executor/execIndexing.c | 3 +- src/backend/executor/execReplication.c | 12 ++-- src/backend/executor/nodeBitmapHeapscan.c | 1 + src/backend/executor/nodeIndexonlyscan.c | 3 + src/backend/executor/nodeIndexscan.c | 4 ++ src/backend/executor/nodeSamplescan.c | 1 + src/backend/executor/nodeSeqscan.c | 6 +- src/backend/executor/nodeTidrangescan.c | 5 +- src/backend/partitioning/partbounds.c | 2 +- src/backend/utils/adt/selfuncs.c | 1 + src/include/access/genam.h | 2 + src/include/access/heapam.h | 5 +- src/include/access/relscan.h | 1 + src/include/access/tableam.h | 68 +++++++++++++++-------- 26 files changed, 111 insertions(+), 62 deletions(-) diff --git a/contrib/pgrowlocks/pgrowlocks.c b/contrib/pgrowlocks/pgrowlocks.c index ff3692c87c4..95fad61fa9e 100644 --- a/contrib/pgrowlocks/pgrowlocks.c +++ b/contrib/pgrowlocks/pgrowlocks.c @@ -115,7 +115,7 @@ pgrowlocks(PG_FUNCTION_ARGS) RelationGetRelationName(rel)); /* Scan the relation */ - scan = table_beginscan(rel, GetActiveSnapshot(), 0, NULL); + scan = table_beginscan(rel, 0, GetActiveSnapshot(), 0, NULL); hscan = (HeapScanDesc) scan; attinmeta = TupleDescGetAttInMetadata(rsinfo->setDesc); diff --git a/src/backend/access/brin/brin.c b/src/backend/access/brin/brin.c index 2a0f8c8e3b8..79a79bea1c6 100644 --- a/src/backend/access/brin/brin.c +++ b/src/backend/access/brin/brin.c @@ -2844,6 +2844,7 @@ _brin_parallel_scan_and_build(BrinBuildState *state, indexInfo->ii_Concurrent = brinshared->isconcurrent; scan = table_beginscan_parallel(heap, + 0, ParallelTableScanFromBrinShared(brinshared)); reltuples = table_index_build_scan(heap, index, indexInfo, true, true, diff --git a/src/backend/access/gin/gininsert.c b/src/backend/access/gin/gininsert.c index e54782d9dd8..32167d03137 100644 --- a/src/backend/access/gin/gininsert.c +++ b/src/backend/access/gin/gininsert.c @@ -2068,6 +2068,7 @@ _gin_parallel_scan_and_build(GinBuildState *state, indexInfo->ii_Concurrent = ginshared->isconcurrent; scan = table_beginscan_parallel(heap, + 0, ParallelTableScanFromGinBuildShared(ginshared)); reltuples = table_index_build_scan(heap, index, indexInfo, true, progress, diff --git a/src/backend/access/heap/heapam_handler.c b/src/backend/access/heap/heapam_handler.c index d40878928e1..951273a4d7f 100644 --- a/src/backend/access/heap/heapam_handler.c +++ b/src/backend/access/heap/heapam_handler.c @@ -81,11 +81,12 @@ heapam_slot_callbacks(Relation relation) */ static IndexFetchTableData * -heapam_index_fetch_begin(Relation rel) +heapam_index_fetch_begin(Relation rel, uint32 flags) { IndexFetchHeapData *hscan = palloc0_object(IndexFetchHeapData); hscan->xs_base.rel = rel; + hscan->xs_base.flags = flags; hscan->xs_cbuf = InvalidBuffer; hscan->xs_vmbuffer = InvalidBuffer; @@ -763,7 +764,9 @@ heapam_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap, tableScan = NULL; heapScan = NULL; - indexScan = index_beginscan(OldHeap, OldIndex, SnapshotAny, NULL, 0, 0); + indexScan = index_beginscan(OldHeap, OldIndex, + 0, /* flags */ + SnapshotAny, NULL, 0, 0); index_rescan(indexScan, NULL, 0, NULL, 0); } else @@ -772,7 +775,7 @@ heapam_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap, pgstat_progress_update_param(PROGRESS_REPACK_PHASE, PROGRESS_REPACK_PHASE_SEQ_SCAN_HEAP); - tableScan = table_beginscan(OldHeap, SnapshotAny, 0, (ScanKey) NULL); + tableScan = table_beginscan(OldHeap, 0, SnapshotAny, 0, (ScanKey) NULL); heapScan = (HeapScanDesc) tableScan; indexScan = NULL; diff --git a/src/backend/access/index/genam.c b/src/backend/access/index/genam.c index 5e89b86a62c..b099d956e41 100644 --- a/src/backend/access/index/genam.c +++ b/src/backend/access/index/genam.c @@ -455,6 +455,7 @@ systable_beginscan(Relation heapRelation, } sysscan->iscan = index_beginscan(heapRelation, irel, + 0, /* flags */ snapshot, NULL, nkeys, 0); index_rescan(sysscan->iscan, idxkey, nkeys, NULL, 0); sysscan->scan = NULL; @@ -716,6 +717,7 @@ systable_beginscan_ordered(Relation heapRelation, bsysscan = true; sysscan->iscan = index_beginscan(heapRelation, indexRelation, + 0, /* flags */ snapshot, NULL, nkeys, 0); index_rescan(sysscan->iscan, idxkey, nkeys, NULL, 0); sysscan->scan = NULL; diff --git a/src/backend/access/index/indexam.c b/src/backend/access/index/indexam.c index fbfc33159eb..ae754503007 100644 --- a/src/backend/access/index/indexam.c +++ b/src/backend/access/index/indexam.c @@ -256,6 +256,7 @@ index_insert_cleanup(Relation indexRelation, IndexScanDesc index_beginscan(Relation heapRelation, Relation indexRelation, + uint32 flags, Snapshot snapshot, IndexScanInstrumentation *instrument, int nkeys, int norderbys) @@ -285,7 +286,7 @@ index_beginscan(Relation heapRelation, scan->instrument = instrument; /* prepare to fetch index matches from table */ - scan->xs_heapfetch = table_index_fetch_begin(heapRelation); + scan->xs_heapfetch = table_index_fetch_begin(heapRelation, flags); return scan; } @@ -592,6 +593,7 @@ index_parallelrescan(IndexScanDesc scan) */ IndexScanDesc index_beginscan_parallel(Relation heaprel, Relation indexrel, + uint32 flags, IndexScanInstrumentation *instrument, int nkeys, int norderbys, ParallelIndexScanDesc pscan) @@ -616,7 +618,7 @@ index_beginscan_parallel(Relation heaprel, Relation indexrel, scan->instrument = instrument; /* prepare to fetch index matches from table */ - scan->xs_heapfetch = table_index_fetch_begin(heaprel); + scan->xs_heapfetch = table_index_fetch_begin(heaprel, flags); return scan; } diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index 47a9bda30c9..98e9410c579 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -1928,7 +1928,7 @@ _bt_parallel_scan_and_sort(BTSpool *btspool, BTSpool *btspool2, indexInfo = BuildIndexInfo(btspool->index); indexInfo->ii_Concurrent = btshared->isconcurrent; scan = table_beginscan_parallel(btspool->heap, - ParallelTableScanFromBTShared(btshared)); + 0, ParallelTableScanFromBTShared(btshared)); reltuples = table_index_build_scan(btspool->heap, btspool->index, indexInfo, true, progress, _bt_build_callback, &buildstate, scan); diff --git a/src/backend/access/table/tableam.c b/src/backend/access/table/tableam.c index dfda1af412e..32bd3fdb7a5 100644 --- a/src/backend/access/table/tableam.c +++ b/src/backend/access/table/tableam.c @@ -118,7 +118,7 @@ table_beginscan_catalog(Relation relation, int nkeys, ScanKeyData *key) Snapshot snapshot = RegisterSnapshot(GetCatalogSnapshot(relid)); return table_beginscan_common(relation, snapshot, nkeys, key, - NULL, flags); + NULL, flags, 0); } @@ -163,10 +163,10 @@ table_parallelscan_initialize(Relation rel, ParallelTableScanDesc pscan, } TableScanDesc -table_beginscan_parallel(Relation relation, ParallelTableScanDesc pscan) +table_beginscan_parallel(Relation relation, uint32 flags, ParallelTableScanDesc pscan) { Snapshot snapshot; - uint32 flags = SO_TYPE_SEQSCAN | + uint32 internal_flags = SO_TYPE_SEQSCAN | SO_ALLOW_STRAT | SO_ALLOW_SYNC | SO_ALLOW_PAGEMODE; Assert(RelFileLocatorEquals(relation->rd_locator, pscan->phs_locator)); @@ -176,7 +176,7 @@ table_beginscan_parallel(Relation relation, ParallelTableScanDesc pscan) /* Snapshot was serialized -- restore it */ snapshot = RestoreSnapshot((char *) pscan + pscan->phs_snapshot_off); RegisterSnapshot(snapshot); - flags |= SO_TEMP_SNAPSHOT; + internal_flags |= SO_TEMP_SNAPSHOT; } else { @@ -185,16 +185,17 @@ table_beginscan_parallel(Relation relation, ParallelTableScanDesc pscan) } return table_beginscan_common(relation, snapshot, 0, NULL, - pscan, flags); + pscan, internal_flags, flags); } TableScanDesc table_beginscan_parallel_tidrange(Relation relation, + uint32 flags, ParallelTableScanDesc pscan) { Snapshot snapshot; - uint32 flags = SO_TYPE_TIDRANGESCAN | SO_ALLOW_PAGEMODE; TableScanDesc sscan; + uint32 internal_flags = SO_TYPE_TIDRANGESCAN | SO_ALLOW_PAGEMODE; Assert(RelFileLocatorEquals(relation->rd_locator, pscan->phs_locator)); @@ -206,7 +207,7 @@ table_beginscan_parallel_tidrange(Relation relation, /* Snapshot was serialized -- restore it */ snapshot = RestoreSnapshot((char *) pscan + pscan->phs_snapshot_off); RegisterSnapshot(snapshot); - flags |= SO_TEMP_SNAPSHOT; + internal_flags |= SO_TEMP_SNAPSHOT; } else { @@ -215,7 +216,7 @@ table_beginscan_parallel_tidrange(Relation relation, } sscan = table_beginscan_common(relation, snapshot, 0, NULL, - pscan, flags); + pscan, internal_flags, flags); return sscan; } @@ -248,7 +249,7 @@ table_index_fetch_tuple_check(Relation rel, bool found; slot = table_slot_create(rel, NULL); - scan = table_index_fetch_begin(rel); + scan = table_index_fetch_begin(rel, 0); found = table_index_fetch_tuple(scan, tid, snapshot, slot, &call_again, all_dead); table_index_fetch_end(scan); diff --git a/src/backend/commands/constraint.c b/src/backend/commands/constraint.c index cc11c47b6f2..37cfbd63938 100644 --- a/src/backend/commands/constraint.c +++ b/src/backend/commands/constraint.c @@ -106,7 +106,7 @@ unique_key_recheck(PG_FUNCTION_ARGS) */ tmptid = checktid; { - IndexFetchTableData *scan = table_index_fetch_begin(trigdata->tg_relation); + IndexFetchTableData *scan = table_index_fetch_begin(trigdata->tg_relation, 0); bool call_again = false; if (!table_index_fetch_tuple(scan, &tmptid, SnapshotSelf, slot, diff --git a/src/backend/commands/copyto.c b/src/backend/commands/copyto.c index faf62d959b4..390b4260ada 100644 --- a/src/backend/commands/copyto.c +++ b/src/backend/commands/copyto.c @@ -1336,7 +1336,7 @@ CopyRelationTo(CopyToState cstate, Relation rel, Relation root_rel, uint64 *proc AttrMap *map = NULL; TupleTableSlot *root_slot = NULL; - scandesc = table_beginscan(rel, GetActiveSnapshot(), 0, NULL); + scandesc = table_beginscan(rel, 0, GetActiveSnapshot(), 0, NULL); slot = table_slot_create(rel, NULL); /* diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index c69c12dc014..14d808671c5 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -6411,7 +6411,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap) * checking all the constraints. */ snapshot = RegisterSnapshot(GetLatestSnapshot()); - scan = table_beginscan(oldrel, snapshot, 0, NULL); + scan = table_beginscan(oldrel, 0, snapshot, 0, NULL); /* * Switch to per-tuple memory context and reset it for each tuple @@ -13980,8 +13980,7 @@ validateForeignKeyConstraint(char *conname, */ snapshot = RegisterSnapshot(GetLatestSnapshot()); slot = table_slot_create(rel, NULL); - scan = table_beginscan(rel, snapshot, 0, NULL); - + scan = table_beginscan(rel, 0, snapshot, 0, NULL); perTupCxt = AllocSetContextCreate(CurrentMemoryContext, "validateForeignKeyConstraint", ALLOCSET_SMALL_SIZES); @@ -22882,7 +22881,7 @@ MergePartitionsMoveRows(List **wqueue, List *mergingPartitions, Relation newPart /* Scan through the rows. */ snapshot = RegisterSnapshot(GetLatestSnapshot()); - scan = table_beginscan(mergingPartition, snapshot, 0, NULL); + scan = table_beginscan(mergingPartition, 0, snapshot, 0, NULL); /* * Switch to per-tuple memory context and reset it for each tuple @@ -23346,7 +23345,7 @@ SplitPartitionMoveRows(List **wqueue, Relation rel, Relation splitRel, /* Scan through the rows. */ snapshot = RegisterSnapshot(GetLatestSnapshot()); - scan = table_beginscan(splitRel, snapshot, 0, NULL); + scan = table_beginscan(splitRel, 0, snapshot, 0, NULL); /* * Switch to per-tuple memory context and reset it for each tuple diff --git a/src/backend/commands/typecmds.c b/src/backend/commands/typecmds.c index 3dab6bb5a79..8c5d5e708a1 100644 --- a/src/backend/commands/typecmds.c +++ b/src/backend/commands/typecmds.c @@ -3185,7 +3185,7 @@ validateDomainNotNullConstraint(Oid domainoid) /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); - scan = table_beginscan(testrel, snapshot, 0, NULL); + scan = table_beginscan(testrel, 0, snapshot, 0, NULL); slot = table_slot_create(testrel, NULL); while (table_scan_getnextslot(scan, ForwardScanDirection, slot)) { @@ -3266,7 +3266,7 @@ validateDomainCheckConstraint(Oid domainoid, const char *ccbin, LOCKMODE lockmod /* Scan all tuples in this relation */ snapshot = RegisterSnapshot(GetLatestSnapshot()); - scan = table_beginscan(testrel, snapshot, 0, NULL); + scan = table_beginscan(testrel, 0, snapshot, 0, NULL); slot = table_slot_create(testrel, NULL); while (table_scan_getnextslot(scan, ForwardScanDirection, slot)) { diff --git a/src/backend/executor/execIndexing.c b/src/backend/executor/execIndexing.c index 9d071e495c6..c46beedeb71 100644 --- a/src/backend/executor/execIndexing.c +++ b/src/backend/executor/execIndexing.c @@ -815,7 +815,8 @@ check_exclusion_or_unique_constraint(Relation heap, Relation index, retry: conflict = false; found_self = false; - index_scan = index_beginscan(heap, index, &DirtySnapshot, NULL, indnkeyatts, 0); + index_scan = index_beginscan(heap, index, 0, /* flags */ + &DirtySnapshot, NULL, indnkeyatts, 0); index_rescan(index_scan, scankeys, indnkeyatts, NULL, 0); while (index_getnext_slot(index_scan, ForwardScanDirection, existing_slot)) diff --git a/src/backend/executor/execReplication.c b/src/backend/executor/execReplication.c index 2497ee7edc5..3ef4d5d8bb2 100644 --- a/src/backend/executor/execReplication.c +++ b/src/backend/executor/execReplication.c @@ -205,7 +205,9 @@ RelationFindReplTupleByIndex(Relation rel, Oid idxoid, skey_attoff = build_replindex_scan_key(skey, rel, idxrel, searchslot); /* Start an index scan. */ - scan = index_beginscan(rel, idxrel, &snap, NULL, skey_attoff, 0); + scan = index_beginscan(rel, idxrel, + 0, /* flags */ + &snap, NULL, skey_attoff, 0); retry: found = false; @@ -383,7 +385,7 @@ RelationFindReplTupleSeq(Relation rel, LockTupleMode lockmode, /* Start a heap scan. */ InitDirtySnapshot(snap); - scan = table_beginscan(rel, &snap, 0, NULL); + scan = table_beginscan(rel, 0, &snap, 0, NULL); scanslot = table_slot_create(rel, NULL); retry: @@ -602,7 +604,7 @@ RelationFindDeletedTupleInfoSeq(Relation rel, TupleTableSlot *searchslot, * not yet committed or those just committed prior to the scan are * excluded in update_most_recent_deletion_info(). */ - scan = table_beginscan(rel, SnapshotAny, 0, NULL); + scan = table_beginscan(rel, 0, SnapshotAny, 0, NULL); scanslot = table_slot_create(rel, NULL); table_rescan(scan, NULL); @@ -666,7 +668,9 @@ RelationFindDeletedTupleInfoByIndex(Relation rel, Oid idxoid, * not yet committed or those just committed prior to the scan are * excluded in update_most_recent_deletion_info(). */ - scan = index_beginscan(rel, idxrel, SnapshotAny, NULL, skey_attoff, 0); + scan = index_beginscan(rel, idxrel, + 0, /* flags */ + SnapshotAny, NULL, skey_attoff, 0); index_rescan(scan, skey, skey_attoff, NULL, 0); diff --git a/src/backend/executor/nodeBitmapHeapscan.c b/src/backend/executor/nodeBitmapHeapscan.c index 7cf8d23c742..7e2c1b7467b 100644 --- a/src/backend/executor/nodeBitmapHeapscan.c +++ b/src/backend/executor/nodeBitmapHeapscan.c @@ -146,6 +146,7 @@ BitmapTableScanSetup(BitmapHeapScanState *node) { node->ss.ss_currentScanDesc = table_beginscan_bm(node->ss.ss_currentRelation, + 0, node->ss.ps.state->es_snapshot, 0, NULL); diff --git a/src/backend/executor/nodeIndexonlyscan.c b/src/backend/executor/nodeIndexonlyscan.c index 9eab81fd1c8..5cacb4b215a 100644 --- a/src/backend/executor/nodeIndexonlyscan.c +++ b/src/backend/executor/nodeIndexonlyscan.c @@ -92,6 +92,7 @@ IndexOnlyNext(IndexOnlyScanState *node) */ scandesc = index_beginscan(node->ss.ss_currentRelation, node->ioss_RelationDesc, + 0, /* flags */ estate->es_snapshot, node->ioss_Instrument, node->ioss_NumScanKeys, @@ -791,6 +792,7 @@ ExecIndexOnlyScanInitializeDSM(IndexOnlyScanState *node, node->ioss_ScanDesc = index_beginscan_parallel(node->ss.ss_currentRelation, node->ioss_RelationDesc, + 0, /* flags */ node->ioss_Instrument, node->ioss_NumScanKeys, node->ioss_NumOrderByKeys, @@ -857,6 +859,7 @@ ExecIndexOnlyScanInitializeWorker(IndexOnlyScanState *node, node->ioss_ScanDesc = index_beginscan_parallel(node->ss.ss_currentRelation, node->ioss_RelationDesc, + 0, /* flags */ node->ioss_Instrument, node->ioss_NumScanKeys, node->ioss_NumOrderByKeys, diff --git a/src/backend/executor/nodeIndexscan.c b/src/backend/executor/nodeIndexscan.c index 06143e94c5a..aaef31dbbad 100644 --- a/src/backend/executor/nodeIndexscan.c +++ b/src/backend/executor/nodeIndexscan.c @@ -110,6 +110,7 @@ IndexNext(IndexScanState *node) */ scandesc = index_beginscan(node->ss.ss_currentRelation, node->iss_RelationDesc, + 0, /* flags */ estate->es_snapshot, node->iss_Instrument, node->iss_NumScanKeys, @@ -206,6 +207,7 @@ IndexNextWithReorder(IndexScanState *node) */ scandesc = index_beginscan(node->ss.ss_currentRelation, node->iss_RelationDesc, + 0, /* flags */ estate->es_snapshot, node->iss_Instrument, node->iss_NumScanKeys, @@ -1727,6 +1729,7 @@ ExecIndexScanInitializeDSM(IndexScanState *node, node->iss_ScanDesc = index_beginscan_parallel(node->ss.ss_currentRelation, node->iss_RelationDesc, + 0, /* flags */ node->iss_Instrument, node->iss_NumScanKeys, node->iss_NumOrderByKeys, @@ -1791,6 +1794,7 @@ ExecIndexScanInitializeWorker(IndexScanState *node, node->iss_ScanDesc = index_beginscan_parallel(node->ss.ss_currentRelation, node->iss_RelationDesc, + 0, /* flags */ node->iss_Instrument, node->iss_NumScanKeys, node->iss_NumOrderByKeys, diff --git a/src/backend/executor/nodeSamplescan.c b/src/backend/executor/nodeSamplescan.c index 6b0d65f752f..cf4dd6a16b4 100644 --- a/src/backend/executor/nodeSamplescan.c +++ b/src/backend/executor/nodeSamplescan.c @@ -294,6 +294,7 @@ tablesample_init(SampleScanState *scanstate) { scanstate->ss.ss_currentScanDesc = table_beginscan_sampling(scanstate->ss.ss_currentRelation, + 0, scanstate->ss.ps.state->es_snapshot, 0, NULL, scanstate->use_bulkread, diff --git a/src/backend/executor/nodeSeqscan.c b/src/backend/executor/nodeSeqscan.c index 8f219f60a93..376e877e87c 100644 --- a/src/backend/executor/nodeSeqscan.c +++ b/src/backend/executor/nodeSeqscan.c @@ -70,7 +70,7 @@ SeqNext(SeqScanState *node) * executing a scan that was planned to be parallel. */ scandesc = table_beginscan(node->ss.ss_currentRelation, - estate->es_snapshot, + 0, estate->es_snapshot, 0, NULL); node->ss.ss_currentScanDesc = scandesc; } @@ -375,7 +375,7 @@ ExecSeqScanInitializeDSM(SeqScanState *node, estate->es_snapshot); shm_toc_insert(pcxt->toc, node->ss.ps.plan->plan_node_id, pscan); node->ss.ss_currentScanDesc = - table_beginscan_parallel(node->ss.ss_currentRelation, pscan); + table_beginscan_parallel(node->ss.ss_currentRelation, 0, pscan); } /* ---------------------------------------------------------------- @@ -408,5 +408,5 @@ ExecSeqScanInitializeWorker(SeqScanState *node, pscan = shm_toc_lookup(pwcxt->toc, node->ss.ps.plan->plan_node_id, false); node->ss.ss_currentScanDesc = - table_beginscan_parallel(node->ss.ss_currentRelation, pscan); + table_beginscan_parallel(node->ss.ss_currentRelation, 0, pscan); } diff --git a/src/backend/executor/nodeTidrangescan.c b/src/backend/executor/nodeTidrangescan.c index 617713bde04..bacd7aa5bc4 100644 --- a/src/backend/executor/nodeTidrangescan.c +++ b/src/backend/executor/nodeTidrangescan.c @@ -243,6 +243,7 @@ TidRangeNext(TidRangeScanState *node) if (scandesc == NULL) { scandesc = table_beginscan_tidrange(node->ss.ss_currentRelation, + 0, estate->es_snapshot, &node->trss_mintid, &node->trss_maxtid); @@ -460,7 +461,7 @@ ExecTidRangeScanInitializeDSM(TidRangeScanState *node, ParallelContext *pcxt) shm_toc_insert(pcxt->toc, node->ss.ps.plan->plan_node_id, pscan); node->ss.ss_currentScanDesc = table_beginscan_parallel_tidrange(node->ss.ss_currentRelation, - pscan); + 0, pscan); } /* ---------------------------------------------------------------- @@ -494,5 +495,5 @@ ExecTidRangeScanInitializeWorker(TidRangeScanState *node, pscan = shm_toc_lookup(pwcxt->toc, node->ss.ps.plan->plan_node_id, false); node->ss.ss_currentScanDesc = table_beginscan_parallel_tidrange(node->ss.ss_currentRelation, - pscan); + 0, pscan); } diff --git a/src/backend/partitioning/partbounds.c b/src/backend/partitioning/partbounds.c index 0ca312ac27d..919df5eef0a 100644 --- a/src/backend/partitioning/partbounds.c +++ b/src/backend/partitioning/partbounds.c @@ -3362,7 +3362,7 @@ check_default_partition_contents(Relation parent, Relation default_rel, econtext = GetPerTupleExprContext(estate); snapshot = RegisterSnapshot(GetLatestSnapshot()); tupslot = table_slot_create(part_rel, &estate->es_tupleTable); - scan = table_beginscan(part_rel, snapshot, 0, NULL); + scan = table_beginscan(part_rel, 0, snapshot, 0, NULL); /* * Switch to per-tuple memory context and reset it for each tuple diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c index 53f85ccde01..0528f8166d8 100644 --- a/src/backend/utils/adt/selfuncs.c +++ b/src/backend/utils/adt/selfuncs.c @@ -7177,6 +7177,7 @@ get_actual_variable_endpoint(Relation heapRel, GlobalVisTestFor(heapRel)); index_scan = index_beginscan(heapRel, indexRel, + 0, /* flags */ &SnapshotNonVacuumable, NULL, 1, 0); /* Set it up for index-only scan */ diff --git a/src/include/access/genam.h b/src/include/access/genam.h index 1a27bf060b3..24b2fda51df 100644 --- a/src/include/access/genam.h +++ b/src/include/access/genam.h @@ -156,6 +156,7 @@ extern void index_insert_cleanup(Relation indexRelation, extern IndexScanDesc index_beginscan(Relation heapRelation, Relation indexRelation, + uint32 flags, Snapshot snapshot, IndexScanInstrumentation *instrument, int nkeys, int norderbys); @@ -182,6 +183,7 @@ extern void index_parallelscan_initialize(Relation heapRelation, extern void index_parallelrescan(IndexScanDesc scan); extern IndexScanDesc index_beginscan_parallel(Relation heaprel, Relation indexrel, + uint32 flags, IndexScanInstrumentation *instrument, int nkeys, int norderbys, ParallelIndexScanDesc pscan); diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h index 9b403203006..e2e07348f37 100644 --- a/src/include/access/heapam.h +++ b/src/include/access/heapam.h @@ -95,10 +95,7 @@ typedef struct HeapScanDescData */ ParallelBlockTableScanWorkerData *rs_parallelworkerdata; - /* - * For sequential scans and bitmap heap scans. The current heap block's - * corresponding page in the visibility map. - */ + /* Current heap block's corresponding page in the visibility map */ Buffer rs_vmbuffer; /* these fields only used in page-at-a-time mode and for bitmap scans */ diff --git a/src/include/access/relscan.h b/src/include/access/relscan.h index ce340c076f8..80ea0b437d1 100644 --- a/src/include/access/relscan.h +++ b/src/include/access/relscan.h @@ -122,6 +122,7 @@ typedef struct ParallelBlockTableScanWorkerData *ParallelBlockTableScanWorker; typedef struct IndexFetchTableData { Relation rel; + uint32 flags; } IndexFetchTableData; struct IndexScanInstrumentation; diff --git a/src/include/access/tableam.h b/src/include/access/tableam.h index 06084752245..e1f90f2b6a7 100644 --- a/src/include/access/tableam.h +++ b/src/include/access/tableam.h @@ -65,6 +65,16 @@ typedef enum ScanOptions SO_TEMP_SNAPSHOT = 1 << 9, } ScanOptions; +/* + * Mask of flags that are set internally by the table_beginscan_* functions + * and must not be passed by callers. + */ +#define SO_INTERNAL_FLAGS \ + (SO_TYPE_SEQSCAN | SO_TYPE_BITMAPSCAN | SO_TYPE_SAMPLESCAN | \ + SO_TYPE_TIDSCAN | SO_TYPE_TIDRANGESCAN | SO_TYPE_ANALYZE | \ + SO_ALLOW_STRAT | SO_ALLOW_SYNC | SO_ALLOW_PAGEMODE | \ + SO_TEMP_SNAPSHOT) + /* * Result codes for table_{update,delete,lock_tuple}, and for visibility * routines inside table AMs. @@ -420,7 +430,7 @@ typedef struct TableAmRoutine * * Tuples for an index scan can then be fetched via index_fetch_tuple. */ - struct IndexFetchTableData *(*index_fetch_begin) (Relation rel); + struct IndexFetchTableData *(*index_fetch_begin) (Relation rel, uint32 flags); /* * Reset index fetch. Typically this will release cross index fetch @@ -871,12 +881,18 @@ extern TupleTableSlot *table_slot_create(Relation relation, List **reglist); * A wrapper around the Table Access Method scan_begin callback, to centralize * error checking. All calls to ->scan_begin() should go through this * function. + * + * The caller-provided user_flags are validated against SO_INTERNAL_FLAGS to + * catch callers that accidentally pass scan-type or other internal flags. */ static TableScanDesc table_beginscan_common(Relation rel, Snapshot snapshot, int nkeys, ScanKeyData *key, ParallelTableScanDesc pscan, - uint32 flags) + uint32 flags, uint32 user_flags) { + Assert((user_flags & SO_INTERNAL_FLAGS) == 0); + flags |= user_flags; + /* * We don't allow scans to be started while CheckXidAlive is set, except * via systable_beginscan() et al. See detailed comments in xact.c where @@ -893,13 +909,14 @@ table_beginscan_common(Relation rel, Snapshot snapshot, int nkeys, * `snapshot`, and if nkeys != 0, the results are filtered by those scan keys. */ static inline TableScanDesc -table_beginscan(Relation rel, Snapshot snapshot, +table_beginscan(Relation rel, uint32 flags, Snapshot snapshot, int nkeys, ScanKeyData *key) { - uint32 flags = SO_TYPE_SEQSCAN | + uint32 internal_flags = SO_TYPE_SEQSCAN | SO_ALLOW_STRAT | SO_ALLOW_SYNC | SO_ALLOW_PAGEMODE; - return table_beginscan_common(rel, snapshot, nkeys, key, NULL, flags); + return table_beginscan_common(rel, snapshot, nkeys, key, NULL, + internal_flags, flags); } /* @@ -928,7 +945,7 @@ table_beginscan_strat(Relation rel, Snapshot snapshot, if (allow_sync) flags |= SO_ALLOW_SYNC; - return table_beginscan_common(rel, snapshot, nkeys, key, NULL, flags); + return table_beginscan_common(rel, snapshot, nkeys, key, NULL, flags, 0); } /* @@ -938,12 +955,13 @@ table_beginscan_strat(Relation rel, Snapshot snapshot, * make it worth using the same data structure. */ static inline TableScanDesc -table_beginscan_bm(Relation rel, Snapshot snapshot, +table_beginscan_bm(Relation rel, uint32 flags, Snapshot snapshot, int nkeys, ScanKeyData *key) { - uint32 flags = SO_TYPE_BITMAPSCAN | SO_ALLOW_PAGEMODE; + uint32 internal_flags = SO_TYPE_BITMAPSCAN | SO_ALLOW_PAGEMODE; - return table_beginscan_common(rel, snapshot, nkeys, key, NULL, flags); + return table_beginscan_common(rel, snapshot, nkeys, key, NULL, + internal_flags, flags); } /* @@ -954,21 +972,22 @@ table_beginscan_bm(Relation rel, Snapshot snapshot, * also allows control of whether page-mode visibility checking is used. */ static inline TableScanDesc -table_beginscan_sampling(Relation rel, Snapshot snapshot, +table_beginscan_sampling(Relation rel, uint32 flags, Snapshot snapshot, int nkeys, ScanKeyData *key, bool allow_strat, bool allow_sync, bool allow_pagemode) { - uint32 flags = SO_TYPE_SAMPLESCAN; + uint32 internal_flags = SO_TYPE_SAMPLESCAN; if (allow_strat) - flags |= SO_ALLOW_STRAT; + internal_flags |= SO_ALLOW_STRAT; if (allow_sync) - flags |= SO_ALLOW_SYNC; + internal_flags |= SO_ALLOW_SYNC; if (allow_pagemode) - flags |= SO_ALLOW_PAGEMODE; + internal_flags |= SO_ALLOW_PAGEMODE; - return table_beginscan_common(rel, snapshot, nkeys, key, NULL, flags); + return table_beginscan_common(rel, snapshot, nkeys, key, NULL, + internal_flags, flags); } /* @@ -981,7 +1000,7 @@ table_beginscan_tid(Relation rel, Snapshot snapshot) { uint32 flags = SO_TYPE_TIDSCAN; - return table_beginscan_common(rel, snapshot, 0, NULL, NULL, flags); + return table_beginscan_common(rel, snapshot, 0, NULL, NULL, flags, 0); } /* @@ -994,7 +1013,7 @@ table_beginscan_analyze(Relation rel) { uint32 flags = SO_TYPE_ANALYZE; - return table_beginscan_common(rel, NULL, 0, NULL, NULL, flags); + return table_beginscan_common(rel, NULL, 0, NULL, NULL, flags, 0); } /* @@ -1057,14 +1076,15 @@ table_scan_getnextslot(TableScanDesc sscan, ScanDirection direction, TupleTableS * for a TID range scan. */ static inline TableScanDesc -table_beginscan_tidrange(Relation rel, Snapshot snapshot, +table_beginscan_tidrange(Relation rel, uint32 flags, Snapshot snapshot, ItemPointer mintid, ItemPointer maxtid) { TableScanDesc sscan; - uint32 flags = SO_TYPE_TIDRANGESCAN | SO_ALLOW_PAGEMODE; + uint32 internal_flags = SO_TYPE_TIDRANGESCAN | SO_ALLOW_PAGEMODE; - sscan = table_beginscan_common(rel, snapshot, 0, NULL, NULL, flags); + sscan = table_beginscan_common(rel, snapshot, 0, NULL, NULL, + internal_flags, flags); /* Set the range of TIDs to scan */ sscan->rs_rd->rd_tableam->scan_set_tidrange(sscan, mintid, maxtid); @@ -1139,6 +1159,7 @@ extern void table_parallelscan_initialize(Relation rel, * Caller must hold a suitable lock on the relation. */ extern TableScanDesc table_beginscan_parallel(Relation relation, + uint32 flags, ParallelTableScanDesc pscan); /* @@ -1149,6 +1170,7 @@ extern TableScanDesc table_beginscan_parallel(Relation relation, * Caller must hold a suitable lock on the relation. */ extern TableScanDesc table_beginscan_parallel_tidrange(Relation relation, + uint32 flags, ParallelTableScanDesc pscan); /* @@ -1175,8 +1197,10 @@ table_parallelscan_reinitialize(Relation rel, ParallelTableScanDesc pscan) * Tuples for an index scan can then be fetched via table_index_fetch_tuple(). */ static inline IndexFetchTableData * -table_index_fetch_begin(Relation rel) +table_index_fetch_begin(Relation rel, uint32 flags) { + Assert((flags & SO_INTERNAL_FLAGS) == 0); + /* * We don't allow scans to be started while CheckXidAlive is set, except * via systable_beginscan() et al. See detailed comments in xact.c where @@ -1185,7 +1209,7 @@ table_index_fetch_begin(Relation rel) if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan)) elog(ERROR, "scan started during logical decoding"); - return rel->rd_tableam->index_fetch_begin(rel); + return rel->rd_tableam->index_fetch_begin(rel, flags); } /* -- 2.43.0