diff options
Diffstat (limited to 'src/backend/utils/cache/relcache.c')
| -rw-r--r-- | src/backend/utils/cache/relcache.c | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c index 9d4ffa4b148..82de42020e8 100644 --- a/src/backend/utils/cache/relcache.c +++ b/src/backend/utils/cache/relcache.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.241 2006/05/06 15:51:07 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.242 2006/06/16 18:42:22 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -313,6 +313,8 @@ AllocateRelationDesc(Relation relation, Form_pg_class relp) /* and allocate attribute tuple form storage */ relation->rd_att = CreateTemplateTupleDesc(relationForm->relnatts, relationForm->relhasoids); + /* which we mark as a reference-counted tupdesc */ + relation->rd_att->tdrefcount = 1; MemoryContextSwitchTo(oldcxt); @@ -1234,6 +1236,8 @@ formrdesc(const char *relationName, Oid relationReltype, * defined by macros in src/include/catalog/ headers. */ relation->rd_att = CreateTemplateTupleDesc(natts, hasoids); + relation->rd_att->tdrefcount = 1; /* mark as refcounted */ + relation->rd_att->tdtypeid = relationReltype; relation->rd_att->tdtypmod = -1; /* unnecessary, but... */ @@ -1591,7 +1595,10 @@ RelationClearRelation(Relation relation, bool rebuild) { /* ok to zap remaining substructure */ flush_rowtype_cache(old_reltype); - FreeTupleDesc(relation->rd_att); + /* can't use DecrTupleDescRefCount here */ + Assert(relation->rd_att->tdrefcount > 0); + if (--relation->rd_att->tdrefcount == 0) + FreeTupleDesc(relation->rd_att); if (relation->rd_rulescxt) MemoryContextDelete(relation->rd_rulescxt); pfree(relation); @@ -1601,7 +1608,10 @@ RelationClearRelation(Relation relation, bool rebuild) /* * When rebuilding an open relcache entry, must preserve ref count and * rd_createSubid state. Also attempt to preserve the tupledesc and - * rewrite-rule substructures in place. + * rewrite-rule substructures in place. (Note: the refcount mechanism + * for tupledescs may eventually ensure that we don't really need to + * preserve the tupledesc in-place, but for now there are still a lot + * of places that assume an open rel's tupledesc won't move.) * * Note that this process does not touch CurrentResourceOwner; which * is good because whatever ref counts the entry may have do not @@ -1618,7 +1628,9 @@ RelationClearRelation(Relation relation, bool rebuild) { /* Should only get here if relation was deleted */ flush_rowtype_cache(old_reltype); - FreeTupleDesc(old_att); + Assert(old_att->tdrefcount > 0); + if (--old_att->tdrefcount == 0) + FreeTupleDesc(old_att); if (old_rulescxt) MemoryContextDelete(old_rulescxt); pfree(relation); @@ -1629,13 +1641,17 @@ RelationClearRelation(Relation relation, bool rebuild) if (equalTupleDescs(old_att, relation->rd_att)) { /* needn't flush typcache here */ - FreeTupleDesc(relation->rd_att); + Assert(relation->rd_att->tdrefcount == 1); + if (--relation->rd_att->tdrefcount == 0) + FreeTupleDesc(relation->rd_att); relation->rd_att = old_att; } else { flush_rowtype_cache(old_reltype); - FreeTupleDesc(old_att); + Assert(old_att->tdrefcount > 0); + if (--old_att->tdrefcount == 0) + FreeTupleDesc(old_att); } if (equalRuleLocks(old_rules, relation->rd_rules)) { @@ -2075,6 +2091,7 @@ RelationBuildLocalRelation(const char *relname, * catalogs. We can copy attnotnull constraints here, however. */ rel->rd_att = CreateTupleDescCopy(tupDesc); + rel->rd_att->tdrefcount = 1; /* mark as refcounted */ has_not_null = false; for (i = 0; i < natts; i++) { @@ -2996,6 +3013,8 @@ load_relcache_init_file(void) /* initialize attribute tuple forms */ rel->rd_att = CreateTemplateTupleDesc(relform->relnatts, relform->relhasoids); + rel->rd_att->tdrefcount = 1; /* mark as refcounted */ + rel->rd_att->tdtypeid = relform->reltype; rel->rd_att->tdtypmod = -1; /* unnecessary, but... */ |