diff options
Diffstat (limited to 'src/backend/access/transam/subtrans.c')
| -rw-r--r-- | src/backend/access/transam/subtrans.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/src/backend/access/transam/subtrans.c b/src/backend/access/transam/subtrans.c index 9c74e995db0..2b9db48f3b0 100644 --- a/src/backend/access/transam/subtrans.c +++ b/src/backend/access/transam/subtrans.c @@ -22,7 +22,7 @@ * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/backend/access/transam/subtrans.c,v 1.24 2009/01/01 17:23:36 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/access/transam/subtrans.c,v 1.25 2009/12/19 01:32:33 sriggs Exp $ * *------------------------------------------------------------------------- */ @@ -68,15 +68,19 @@ static bool SubTransPagePrecedes(int page1, int page2); /* * Record the parent of a subtransaction in the subtrans log. + * + * In some cases we may need to overwrite an existing value. */ void -SubTransSetParent(TransactionId xid, TransactionId parent) +SubTransSetParent(TransactionId xid, TransactionId parent, bool overwriteOK) { int pageno = TransactionIdToPage(xid); int entryno = TransactionIdToEntry(xid); int slotno; TransactionId *ptr; + Assert(TransactionIdIsValid(parent)); + LWLockAcquire(SubtransControlLock, LW_EXCLUSIVE); slotno = SimpleLruReadPage(SubTransCtl, pageno, true, xid); @@ -84,7 +88,8 @@ SubTransSetParent(TransactionId xid, TransactionId parent) ptr += entryno; /* Current state should be 0 */ - Assert(*ptr == InvalidTransactionId); + Assert(*ptr == InvalidTransactionId || + (*ptr == parent && overwriteOK)); *ptr = parent; |