diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2006-11-17 18:00:25 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2006-11-17 18:00:25 +0000 |
| commit | 91eb4895bb6c57face2edf30e20e16e6ab942ef1 (patch) | |
| tree | cfbd90e4ac556bc7e16c46b542f3e733de323375 /src/backend/utils | |
| parent | a2281c8e6f5ffe4fa67584f850bfa077e526115e (diff) | |
Repair two related errors in heap_lock_tuple: it was failing to recognize
cases where we already hold the desired lock "indirectly", either via
membership in a MultiXact or because the lock was originally taken by a
different subtransaction of the current transaction. These cases must be
accounted for to avoid needless deadlocks and/or inappropriate replacement of
an exclusive lock with a shared lock. Per report from Clarence Gardner and
subsequent investigation.
Diffstat (limited to 'src/backend/utils')
| -rw-r--r-- | src/backend/utils/time/tqual.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/src/backend/utils/time/tqual.c b/src/backend/utils/time/tqual.c index 27b712a22ae..4c1c8612c2c 100644 --- a/src/backend/utils/time/tqual.c +++ b/src/backend/utils/time/tqual.c @@ -32,7 +32,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.91.2.1 2005/11/22 18:23:25 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.91.2.2 2006/11/17 18:00:25 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -506,7 +506,10 @@ HeapTupleSatisfiesToast(HeapTupleHeader tuple, Buffer buffer) * HeapTupleUpdated: The tuple was updated by a committed transaction. * * HeapTupleBeingUpdated: The tuple is being updated by an in-progress - * transaction other than the current transaction. + * transaction other than the current transaction. (Note: this includes + * the case where the tuple is share-locked by a MultiXact, even if the + * MultiXact includes the current transaction. Callers that want to + * distinguish that case must test for it themselves.) */ HTSU_Result HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid, |