diff options
Diffstat (limited to 'src/backend/access/transam/xlog.c')
| -rw-r--r-- | src/backend/access/transam/xlog.c | 34 |
1 files changed, 19 insertions, 15 deletions
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 1dd31b37ffe..939813e7b71 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -1408,9 +1408,7 @@ WALInsertLockAcquire(void) * The insertingAt value is initially set to 0, as we don't know our * insert location yet. */ - immed = LWLockAcquireWithVar(&WALInsertLocks[MyLockNo].l.lock, - &WALInsertLocks[MyLockNo].l.insertingAt, - 0); + immed = LWLockAcquire(&WALInsertLocks[MyLockNo].l.lock, LW_EXCLUSIVE); if (!immed) { /* @@ -1435,26 +1433,28 @@ WALInsertLockAcquireExclusive(void) int i; /* - * When holding all the locks, we only update the last lock's insertingAt - * indicator. The others are set to 0xFFFFFFFFFFFFFFFF, which is higher - * than any real XLogRecPtr value, to make sure that no-one blocks waiting - * on those. + * When holding all the locks, all but the last lock's insertingAt + * indicator is set to 0xFFFFFFFFFFFFFFFF, which is higher than any real + * XLogRecPtr value, to make sure that no-one blocks waiting on those. */ for (i = 0; i < NUM_XLOGINSERT_LOCKS - 1; i++) { - LWLockAcquireWithVar(&WALInsertLocks[i].l.lock, - &WALInsertLocks[i].l.insertingAt, - PG_UINT64_MAX); + LWLockAcquire(&WALInsertLocks[i].l.lock, LW_EXCLUSIVE); + LWLockUpdateVar(&WALInsertLocks[i].l.lock, + &WALInsertLocks[i].l.insertingAt, + PG_UINT64_MAX); } - LWLockAcquireWithVar(&WALInsertLocks[i].l.lock, - &WALInsertLocks[i].l.insertingAt, - 0); + /* Variable value reset to 0 at release */ + LWLockAcquire(&WALInsertLocks[i].l.lock, LW_EXCLUSIVE); holdingAllLocks = true; } /* * Release our insertion lock (or locks, if we're holding them all). + * + * NB: Reset all variables to 0, so they cause LWLockWaitForVar to block the + * next time the lock is acquired. */ static void WALInsertLockRelease(void) @@ -1464,13 +1464,17 @@ WALInsertLockRelease(void) int i; for (i = 0; i < NUM_XLOGINSERT_LOCKS; i++) - LWLockRelease(&WALInsertLocks[i].l.lock); + LWLockReleaseClearVar(&WALInsertLocks[i].l.lock, + &WALInsertLocks[i].l.insertingAt, + 0); holdingAllLocks = false; } else { - LWLockRelease(&WALInsertLocks[MyLockNo].l.lock); + LWLockReleaseClearVar(&WALInsertLocks[MyLockNo].l.lock, + &WALInsertLocks[MyLockNo].l.insertingAt, + 0); } } |