diff options
Diffstat (limited to 'src/backend/storage/lmgr/proc.c')
| -rw-r--r-- | src/backend/storage/lmgr/proc.c | 41 |
1 files changed, 33 insertions, 8 deletions
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c index 2a79f8247a..f4091ecc0f 100644 --- a/src/backend/storage/lmgr/proc.c +++ b/src/backend/storage/lmgr/proc.c @@ -196,9 +196,11 @@ InitProcGlobal(void) for (i = 0; i < TotalProcs; i++) { /* Common initialization for all PGPROCs, regardless of type. */ + + /* Set up per-PGPROC semaphore, latch, and backendLock */ PGSemaphoreCreate(&(procs[i].sem)); + InitSharedLatch(&(procs[i].procLatch)); procs[i].backendLock = LWLockAssign(); - InitSharedLatch(&procs[i].waitLatch); /* * Newly created PGPROCs for normal backends or for autovacuum must @@ -300,8 +302,8 @@ InitProcess(void) MarkPostmasterChildActive(); /* - * Initialize all fields of MyProc, except for the semaphore which was - * prepared for us by InitProcGlobal. + * Initialize all fields of MyProc, except for the semaphore and latch, + * which were prepared for us by InitProcGlobal. */ SHMQueueElemInit(&(MyProc->links)); MyProc->waitStatus = STATUS_OK; @@ -327,12 +329,17 @@ InitProcess(void) SHMQueueInit(&(MyProc->myProcLocks[i])); MyProc->recoveryConflictPending = false; - /* Initialise for sync rep */ + /* Initialize fields for sync rep */ MyProc->waitLSN.xlogid = 0; MyProc->waitLSN.xrecoff = 0; MyProc->syncRepState = SYNC_REP_NOT_WAITING; SHMQueueElemInit(&(MyProc->syncRepLinks)); - OwnLatch(&MyProc->waitLatch); + + /* + * Acquire ownership of the PGPROC's latch, so that we can use WaitLatch. + * Note that there's no particular need to do ResetLatch here. + */ + OwnLatch(&MyProc->procLatch); /* * We might be reusing a semaphore that belonged to a failed process. So @@ -373,7 +380,6 @@ InitProcessPhase2(void) /* * Arrange to clean that up at backend exit. */ - on_shmem_exit(SyncRepCleanupAtProcExit, 0); on_shmem_exit(RemoveProcFromArray, 0); } @@ -448,8 +454,8 @@ InitAuxiliaryProcess(void) SpinLockRelease(ProcStructLock); /* - * Initialize all fields of MyProc, except for the semaphore which was - * prepared for us by InitProcGlobal. + * Initialize all fields of MyProc, except for the semaphore and latch, + * which were prepared for us by InitProcGlobal. */ SHMQueueElemInit(&(MyProc->links)); MyProc->waitStatus = STATUS_OK; @@ -470,6 +476,12 @@ InitAuxiliaryProcess(void) SHMQueueInit(&(MyProc->myProcLocks[i])); /* + * Acquire ownership of the PGPROC's latch, so that we can use WaitLatch. + * Note that there's no particular need to do ResetLatch here. + */ + OwnLatch(&MyProc->procLatch); + + /* * We might be reusing a semaphore that belonged to a failed process. So * be careful and reinitialize its value here. (This is not strictly * necessary anymore, but seems like a good idea for cleanliness.) @@ -671,6 +683,9 @@ ProcKill(int code, Datum arg) Assert(MyProc != NULL); + /* Make sure we're out of the sync rep lists */ + SyncRepCleanupAtProcExit(); + /* * Release any LW locks I am holding. There really shouldn't be any, but * it's cheap to check again before we cut the knees off the LWLock @@ -678,6 +693,9 @@ ProcKill(int code, Datum arg) */ LWLockReleaseAll(); + /* Release ownership of the process's latch, too */ + DisownLatch(&MyProc->procLatch); + SpinLockAcquire(ProcStructLock); /* Return PGPROC structure (and semaphore) to appropriate freelist */ @@ -733,6 +751,9 @@ AuxiliaryProcKill(int code, Datum arg) /* Release any LW locks I am holding (see notes above) */ LWLockReleaseAll(); + /* Release ownership of the process's latch, too */ + DisownLatch(&MyProc->procLatch); + SpinLockAcquire(ProcStructLock); /* Mark auxiliary proc no longer in use */ @@ -1610,6 +1631,10 @@ handle_sig_alarm(SIGNAL_ARGS) { int save_errno = errno; + /* SIGALRM is cause for waking anything waiting on the process latch */ + if (MyProc) + SetLatch(&MyProc->procLatch); + if (deadlock_timeout_active) { deadlock_timeout_active = false; |