diff options
Diffstat (limited to 'src/backend/storage/ipc/sinval.c')
| -rw-r--r-- | src/backend/storage/ipc/sinval.c | 35 |
1 files changed, 16 insertions, 19 deletions
diff --git a/src/backend/storage/ipc/sinval.c b/src/backend/storage/ipc/sinval.c index 3f063989e0c..1b6f3b2fc44 100644 --- a/src/backend/storage/ipc/sinval.c +++ b/src/backend/storage/ipc/sinval.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/storage/ipc/sinval.c,v 1.90 2009/06/11 14:49:02 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/storage/ipc/sinval.c,v 1.91 2009/07/31 20:26:23 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -26,8 +26,8 @@ * Because backends sitting idle will not be reading sinval events, we * need a way to give an idle backend a swift kick in the rear and make * it catch up before the sinval queue overflows and forces it to go - * through a cache reset exercise. This is done by sending SIGUSR1 - * to any backend that gets too far behind. + * through a cache reset exercise. This is done by sending + * PROCSIG_CATCHUP_INTERRUPT to any backend that gets too far behind. * * State for catchup events consists of two flags: one saying whether * the signal handler is currently allowed to call ProcessCatchupEvent @@ -145,9 +145,9 @@ ReceiveSharedInvalidMessages( /* - * CatchupInterruptHandler + * HandleCatchupInterrupt * - * This is the signal handler for SIGUSR1. + * This is called when PROCSIG_CATCHUP_INTERRUPT is received. * * If we are idle (catchupInterruptEnabled is set), we can safely * invoke ProcessCatchupEvent directly. Otherwise, just set a flag @@ -157,13 +157,11 @@ ReceiveSharedInvalidMessages( * since there's no longer any reason to do anything.) */ void -CatchupInterruptHandler(SIGNAL_ARGS) +HandleCatchupInterrupt(void) { - int save_errno = errno; - /* - * Note: this is a SIGNAL HANDLER. You must be very wary what you do - * here. + * Note: this is called by a SIGNAL HANDLER. You must be very wary what + * you do here. */ /* Don't joggle the elbow of proc_exit */ @@ -217,8 +215,6 @@ CatchupInterruptHandler(SIGNAL_ARGS) */ catchupInterruptOccurred = 1; } - - errno = save_errno; } /* @@ -273,8 +269,8 @@ EnableCatchupInterrupt(void) * a frontend command. Signal handler execution of catchup events * is disabled until the next EnableCatchupInterrupt call. * - * The SIGUSR2 signal handler also needs to call this, so as to - * prevent conflicts if one signal interrupts the other. So we + * The PROCSIG_NOTIFY_INTERRUPT signal handler also needs to call this, + * so as to prevent conflicts if one signal interrupts the other. So we * must return the previous state of the flag. */ bool @@ -290,18 +286,19 @@ DisableCatchupInterrupt(void) /* * ProcessCatchupEvent * - * Respond to a catchup event (SIGUSR1) from another backend. + * Respond to a catchup event (PROCSIG_CATCHUP_INTERRUPT) from another + * backend. * - * This is called either directly from the SIGUSR1 signal handler, - * or the next time control reaches the outer idle loop (assuming - * there's still anything to do by then). + * This is called either directly from the PROCSIG_CATCHUP_INTERRUPT + * signal handler, or the next time control reaches the outer idle loop + * (assuming there's still anything to do by then). */ static void ProcessCatchupEvent(void) { bool notify_enabled; - /* Must prevent SIGUSR2 interrupt while I am running */ + /* Must prevent notify interrupt while I am running */ notify_enabled = DisableNotifyInterrupt(); /* |