diff options
Diffstat (limited to 'src/backend/access/transam/xact.c')
| -rw-r--r-- | src/backend/access/transam/xact.c | 67 |
1 files changed, 19 insertions, 48 deletions
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c index 4c18ac5a56a..64671792315 100644 --- a/src/backend/access/transam/xact.c +++ b/src/backend/access/transam/xact.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.105 2001/07/06 21:04:25 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.106 2001/07/12 04:11:13 tgl Exp $ * * NOTES * Transaction aborts can now occur two ways: @@ -199,14 +199,9 @@ static void StartTransaction(void); /* ---------------- * global variables holding the current transaction state. - * - * Note: when we are running several slave processes, the - * current transaction state data is copied into shared memory - * and the CurrentTransactionState pointer changed to - * point to the shared copy. All this occurrs in slaves.c * ---------------- */ -TransactionStateData CurrentTransactionStateData = { +static TransactionStateData CurrentTransactionStateData = { 0, /* transaction id */ FirstCommandId, /* command id */ 0, /* scan command id */ @@ -234,29 +229,17 @@ static void *_RollbackData = NULL; * info returned when the system is disabled * * Apparently a lot of this code is inherited from other prototype systems. + * * For DisabledStartTime, use a symbolic value to make the relationships clearer. * The old value of 1073741823 corresponds to a date in y2004, which is coming closer * every day. It appears that if we return a value guaranteed larger than * any real time associated with a transaction then comparisons in other * modules will still be correct. Let's use BIG_ABSTIME for this. tgl 2/14/97 - * - * Note: I have no idea what the significance of the - * 1073741823 in DisabledStartTime.. I just carried - * this over when converting things from the old - * V1 transaction system. -cim 3/18/90 * ---------------- */ -TransactionId DisabledTransactionId = (TransactionId) -1; +static CommandId DisabledCommandId = (CommandId) -1; -CommandId DisabledCommandId = (CommandId) -1; - -AbsoluteTime DisabledStartTime = (AbsoluteTime) BIG_ABSTIME; /* 1073741823; */ - -/* ---------------- - * overflow flag - * ---------------- - */ -bool CommandIdCounterOverflowFlag; +static AbsoluteTime DisabledStartTime = (AbsoluteTime) BIG_ABSTIME; /* ---------------- * catalog creation transaction bootstrapping flag. @@ -362,7 +345,7 @@ IsAbortedTransactionBlockState(void) * themselves. * -------------------------------- */ -int SavedTransactionState; +static int SavedTransactionState; void OverrideTransactionSystem(bool flag) @@ -403,12 +386,12 @@ GetCurrentTransactionId(void) * "disabled" transaction id. */ if (s->state == TRANS_DISABLED) - return (TransactionId) DisabledTransactionId; + return DisabledTransactionId; /* * otherwise return the current transaction id. */ - return (TransactionId) s->transactionIdData; + return s->transactionIdData; } @@ -426,7 +409,7 @@ GetCurrentCommandId(void) * "disabled" command id. */ if (s->state == TRANS_DISABLED) - return (CommandId) DisabledCommandId; + return DisabledCommandId; return s->commandId; } @@ -441,7 +424,7 @@ GetScanCommandId(void) * "disabled" command id. */ if (s->state == TRANS_DISABLED) - return (CommandId) DisabledCommandId; + return DisabledCommandId; return s->scanCommandId; } @@ -461,7 +444,7 @@ GetCurrentTransactionStartTime(void) * "disabled" starting time. */ if (s->state == TRANS_DISABLED) - return (AbsoluteTime) DisabledStartTime; + return DisabledStartTime; return s->startTime; } @@ -479,8 +462,7 @@ TransactionIdIsCurrentTransactionId(TransactionId xid) if (AMI_OVERRIDE) return false; - return (bool) - TransactionIdEquals(xid, s->transactionIdData); + return TransactionIdEquals(xid, s->transactionIdData); } @@ -512,19 +494,6 @@ CommandIdGEScanCommandId(CommandId cid) /* -------------------------------- - * ClearCommandIdCounterOverflowFlag - * -------------------------------- - */ -#ifdef NOT_USED -void -ClearCommandIdCounterOverflowFlag(void) -{ - CommandIdCounterOverflowFlag = false; -} - -#endif - -/* -------------------------------- * CommandCounterIncrement * -------------------------------- */ @@ -533,10 +502,7 @@ CommandCounterIncrement(void) { CurrentTransactionStateData.commandId += 1; if (CurrentTransactionStateData.commandId == FirstCommandId) - { - CommandIdCounterOverflowFlag = true; elog(ERROR, "You may only have 2^32-1 commands per transaction"); - } CurrentTransactionStateData.scanCommandId = CurrentTransactionStateData.commandId; @@ -551,9 +517,7 @@ CommandCounterIncrement(void) void SetScanCommandId(CommandId savedId) { - CurrentTransactionStateData.scanCommandId = savedId; - } /* ---------------------------------------------------------------- @@ -1113,6 +1077,13 @@ AbortTransaction(void) /* * Let others to know about no transaction in progress - vadim * 11/26/96 + * + * XXX it'd be nice to acquire SInvalLock for this, but too much risk of + * lockup: what if we were holding SInvalLock when we elog'd? Net effect + * is that we are relying on fetch/store of an xid to be atomic, else + * other backends might see a partially-zeroed xid here. Would it be + * safe to release spins before we reset xid/xmin? But see also + * GetNewTransactionId, which does the same thing. */ if (MyProc != (PROC *) NULL) { |