diff options
Diffstat (limited to 'src/backend/utils/time/snapmgr.c')
| -rw-r--r-- | src/backend/utils/time/snapmgr.c | 68 |
1 files changed, 54 insertions, 14 deletions
diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c index 1107abdf27a..d37dc5df84c 100644 --- a/src/backend/utils/time/snapmgr.c +++ b/src/backend/utils/time/snapmgr.c @@ -19,7 +19,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/time/snapmgr.c,v 1.7 2008/11/25 20:28:29 alvherre Exp $ + * $PostgreSQL: pgsql/src/backend/utils/time/snapmgr.c,v 1.8 2008/12/04 14:51:02 alvherre Exp $ * *------------------------------------------------------------------------- */ @@ -136,7 +136,8 @@ GetTransactionSnapshot(void) */ if (IsXactIsoLevelSerializable) { - CurrentSnapshot = RegisterSnapshot(CurrentSnapshot); + CurrentSnapshot = RegisterSnapshotOnOwner(CurrentSnapshot, + TopTransactionResourceOwner); registered_serializable = true; } @@ -345,14 +346,27 @@ ActiveSnapshotSet(void) /* * RegisterSnapshot - * Register a snapshot as being in use + * Register a snapshot as being in use by the current resource owner * * If InvalidSnapshot is passed, it is not registered. */ Snapshot RegisterSnapshot(Snapshot snapshot) { - Snapshot snap; + if (snapshot == InvalidSnapshot) + return InvalidSnapshot; + + return RegisterSnapshotOnOwner(snapshot, CurrentResourceOwner); +} + +/* + * RegisterSnapshotOnOwner + * As above, but use the specified resource owner + */ +Snapshot +RegisterSnapshotOnOwner(Snapshot snapshot, ResourceOwner owner) +{ + Snapshot snap; if (snapshot == InvalidSnapshot) return InvalidSnapshot; @@ -361,9 +375,9 @@ RegisterSnapshot(Snapshot snapshot) snap = snapshot->copied ? snapshot : CopySnapshot(snapshot); /* and tell resowner.c about it */ - ResourceOwnerEnlargeSnapshots(CurrentResourceOwner); + ResourceOwnerEnlargeSnapshots(owner); snap->regd_count++; - ResourceOwnerRememberSnapshot(CurrentResourceOwner, snap); + ResourceOwnerRememberSnapshot(owner, snap); RegisteredSnapshots++; @@ -383,10 +397,23 @@ UnregisterSnapshot(Snapshot snapshot) if (snapshot == NULL) return; + UnregisterSnapshotFromOwner(snapshot, CurrentResourceOwner); +} + +/* + * UnregisterSnapshotFromOwner + * As above, but use the specified resource owner + */ +void +UnregisterSnapshotFromOwner(Snapshot snapshot, ResourceOwner owner) +{ + if (snapshot == NULL) + return; + Assert(snapshot->regd_count > 0); Assert(RegisteredSnapshots > 0); - ResourceOwnerForgetSnapshot(CurrentResourceOwner, snapshot); + ResourceOwnerForgetSnapshot(owner, snapshot); RegisteredSnapshots--; if (--snapshot->regd_count == 0 && snapshot->active_count == 0) { @@ -464,6 +491,26 @@ AtSubAbort_Snapshot(int level) } /* + * AtEarlyCommit_Snapshot + * + * Snapshot manager's cleanup function, to be called on commit, before + * doing resowner.c resource release. + */ +void +AtEarlyCommit_Snapshot(void) +{ + /* + * On a serializable transaction we must unregister our private refcount to + * the serializable snapshot. + */ + if (registered_serializable) + UnregisterSnapshotFromOwner(CurrentSnapshot, + TopTransactionResourceOwner); + registered_serializable = false; + +} + +/* * AtEOXact_Snapshot * Snapshot manager's cleanup function for end of transaction */ @@ -475,13 +522,6 @@ AtEOXact_Snapshot(bool isCommit) { ActiveSnapshotElt *active; - /* - * On a serializable snapshot we must first unregister our private - * refcount to the serializable snapshot. - */ - if (registered_serializable) - UnregisterSnapshot(CurrentSnapshot); - if (RegisteredSnapshots != 0) elog(WARNING, "%d registered snapshots seem to remain after cleanup", RegisteredSnapshots); |