diff options
Diffstat (limited to 'src/backend/commands/tablecmds.c')
| -rw-r--r-- | src/backend/commands/tablecmds.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index abb262b851c..a6a9f54b13e 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -271,6 +271,7 @@ struct DropRelationCallbackState { char relkind; Oid heapOid; + Oid partParentOid; bool concurrent; }; @@ -1049,6 +1050,7 @@ RemoveRelations(DropStmt *drop) /* Look up the appropriate relation using namespace search. */ state.relkind = relkind; state.heapOid = InvalidOid; + state.partParentOid = InvalidOid; state.concurrent = drop->concurrent; relOid = RangeVarGetRelidExtended(rel, lockmode, true, false, @@ -1078,6 +1080,8 @@ RemoveRelations(DropStmt *drop) /* * Before acquiring a table lock, check whether we have sufficient rights. * In the case of DROP INDEX, also try to lock the table before the index. + * Also, if the table to be dropped is a partition, we try to lock the parent + * first. */ static void RangeVarCallbackForDropRelation(const RangeVar *rel, Oid relOid, Oid oldRelOid, @@ -1087,6 +1091,7 @@ RangeVarCallbackForDropRelation(const RangeVar *rel, Oid relOid, Oid oldRelOid, struct DropRelationCallbackState *state; char relkind; char expected_relkind; + bool is_partition; Form_pg_class classform; LOCKMODE heap_lockmode; @@ -1106,6 +1111,17 @@ RangeVarCallbackForDropRelation(const RangeVar *rel, Oid relOid, Oid oldRelOid, state->heapOid = InvalidOid; } + /* + * Similarly, if we previously locked some other partition's heap, and + * the name we're looking up no longer refers to that relation, release + * the now-useless lock. + */ + if (relOid != oldRelOid && OidIsValid(state->partParentOid)) + { + UnlockRelationOid(state->partParentOid, AccessExclusiveLock); + state->partParentOid = InvalidOid; + } + /* Didn't find a relation, so no need for locking or permission checks. */ if (!OidIsValid(relOid)) return; @@ -1114,6 +1130,7 @@ RangeVarCallbackForDropRelation(const RangeVar *rel, Oid relOid, Oid oldRelOid, if (!HeapTupleIsValid(tuple)) return; /* concurrently dropped, so nothing to do */ classform = (Form_pg_class) GETSTRUCT(tuple); + is_partition = classform->relispartition; /* * Both RELKIND_RELATION and RELKIND_PARTITIONED_TABLE are OBJECT_TABLE, @@ -1157,6 +1174,19 @@ RangeVarCallbackForDropRelation(const RangeVar *rel, Oid relOid, Oid oldRelOid, if (OidIsValid(state->heapOid)) LockRelationOid(state->heapOid, heap_lockmode); } + + /* + * Similarly, if the relation is a partition, we must acquire lock on its + * parent before locking the partition. That's because queries lock the + * parent before its partitions, so we risk deadlock it we do it the other + * way around. + */ + if (is_partition && relOid != oldRelOid) + { + state->partParentOid = get_partition_parent(relOid); + if (OidIsValid(state->partParentOid)) + LockRelationOid(state->partParentOid, AccessExclusiveLock); + } } /* |