diff --git a/src/backend/postmaster/bgworker.c b/src/backend/postmaster/bgworker.c index f651bb49b15..d2b695e1462 100644 --- a/src/backend/postmaster/bgworker.c +++ b/src/backend/postmaster/bgworker.c @@ -644,28 +644,21 @@ SanityCheckBackgroundWorker(BackgroundWorker *worker, int elevel) static void bgworker_quickdie(SIGNAL_ARGS) { - sigaddset(&BlockSig, SIGQUIT); /* prevent nested calls */ - PG_SETMASK(&BlockSig); - /* - * We DO NOT want to run proc_exit() callbacks -- we're here because - * shared memory may be corrupted, so we don't want to try to clean up our - * transaction. Just nail the windows shut and get out of town. Now that - * there's an atexit callback to prevent third-party code from breaking - * things by calling exit() directly, we have to reset the callbacks - * explicitly to make this work as intended. - */ - on_exit_reset(); - - /* - * Note we do exit(2) not exit(0). This is to force the postmaster into a - * system reset cycle if some idiot DBA sends a manual SIGQUIT to a random + * We DO NOT want to run proc_exit() or atexit() callbacks -- we're here + * because shared memory may be corrupted, so we don't want to try to + * clean up our transaction. Just nail the windows shut and get out of + * town. The callbacks wouldn't be safe to run from a signal handler, + * anyway. + * + * Note we do _exit(2) not _exit(0). This is to force the postmaster into + * a system reset cycle if someone sends a manual SIGQUIT to a random * backend. This is necessary precisely because we don't clean up our * shared memory state. (The "dead man switch" mechanism in pmsignal.c * should ensure the postmaster sees this as a crash, too, but no harm in * being doubly sure.) */ - exit(2); + _exit(2); } /* diff --git a/src/backend/postmaster/bgwriter.c b/src/backend/postmaster/bgwriter.c index d5ce685e54f..3e6ffb05b90 100644 --- a/src/backend/postmaster/bgwriter.c +++ b/src/backend/postmaster/bgwriter.c @@ -409,27 +409,21 @@ BackgroundWriterMain(void) static void bg_quickdie(SIGNAL_ARGS) { - PG_SETMASK(&BlockSig); - /* - * We DO NOT want to run proc_exit() callbacks -- we're here because - * shared memory may be corrupted, so we don't want to try to clean up our - * transaction. Just nail the windows shut and get out of town. Now that - * there's an atexit callback to prevent third-party code from breaking - * things by calling exit() directly, we have to reset the callbacks - * explicitly to make this work as intended. - */ - on_exit_reset(); - - /* - * Note we do exit(2) not exit(0). This is to force the postmaster into a - * system reset cycle if some idiot DBA sends a manual SIGQUIT to a random + * We DO NOT want to run proc_exit() or atexit() callbacks -- we're here + * because shared memory may be corrupted, so we don't want to try to + * clean up our transaction. Just nail the windows shut and get out of + * town. The callbacks wouldn't be safe to run from a signal handler, + * anyway. + * + * Note we do _exit(2) not _exit(0). This is to force the postmaster into + * a system reset cycle if someone sends a manual SIGQUIT to a random * backend. This is necessary precisely because we don't clean up our * shared memory state. (The "dead man switch" mechanism in pmsignal.c * should ensure the postmaster sees this as a crash, too, but no harm in * being doubly sure.) */ - exit(2); + _exit(2); } /* SIGHUP: set flag to re-read config file at next convenient time */ diff --git a/src/backend/postmaster/checkpointer.c b/src/backend/postmaster/checkpointer.c index 0950ada6019..b54448017d6 100644 --- a/src/backend/postmaster/checkpointer.c +++ b/src/backend/postmaster/checkpointer.c @@ -823,27 +823,21 @@ IsCheckpointOnSchedule(double progress) static void chkpt_quickdie(SIGNAL_ARGS) { - PG_SETMASK(&BlockSig); - /* - * We DO NOT want to run proc_exit() callbacks -- we're here because - * shared memory may be corrupted, so we don't want to try to clean up our - * transaction. Just nail the windows shut and get out of town. Now that - * there's an atexit callback to prevent third-party code from breaking - * things by calling exit() directly, we have to reset the callbacks - * explicitly to make this work as intended. - */ - on_exit_reset(); - - /* - * Note we do exit(2) not exit(0). This is to force the postmaster into a - * system reset cycle if some idiot DBA sends a manual SIGQUIT to a random + * We DO NOT want to run proc_exit() or atexit() callbacks -- we're here + * because shared memory may be corrupted, so we don't want to try to + * clean up our transaction. Just nail the windows shut and get out of + * town. The callbacks wouldn't be safe to run from a signal handler, + * anyway. + * + * Note we do _exit(2) not _exit(0). This is to force the postmaster into + * a system reset cycle if someone sends a manual SIGQUIT to a random * backend. This is necessary precisely because we don't clean up our * shared memory state. (The "dead man switch" mechanism in pmsignal.c * should ensure the postmaster sees this as a crash, too, but no harm in * being doubly sure.) */ - exit(2); + _exit(2); } /* SIGHUP: set flag to re-read config file at next convenient time */ diff --git a/src/backend/postmaster/startup.c b/src/backend/postmaster/startup.c index 38300527a54..2926211e35d 100644 --- a/src/backend/postmaster/startup.c +++ b/src/backend/postmaster/startup.c @@ -69,27 +69,21 @@ static void StartupProcSigHupHandler(SIGNAL_ARGS); static void startupproc_quickdie(SIGNAL_ARGS) { - PG_SETMASK(&BlockSig); - /* - * We DO NOT want to run proc_exit() callbacks -- we're here because - * shared memory may be corrupted, so we don't want to try to clean up our - * transaction. Just nail the windows shut and get out of town. Now that - * there's an atexit callback to prevent third-party code from breaking - * things by calling exit() directly, we have to reset the callbacks - * explicitly to make this work as intended. - */ - on_exit_reset(); - - /* - * Note we do exit(2) not exit(0). This is to force the postmaster into a - * system reset cycle if some idiot DBA sends a manual SIGQUIT to a random + * We DO NOT want to run proc_exit() or atexit() callbacks -- we're here + * because shared memory may be corrupted, so we don't want to try to + * clean up our transaction. Just nail the windows shut and get out of + * town. The callbacks wouldn't be safe to run from a signal handler, + * anyway. + * + * Note we do _exit(2) not _exit(0). This is to force the postmaster into + * a system reset cycle if someone sends a manual SIGQUIT to a random * backend. This is necessary precisely because we don't clean up our * shared memory state. (The "dead man switch" mechanism in pmsignal.c * should ensure the postmaster sees this as a crash, too, but no harm in * being doubly sure.) */ - exit(2); + _exit(2); } diff --git a/src/backend/postmaster/walwriter.c b/src/backend/postmaster/walwriter.c index 688d5b5b80b..33bbb539fe0 100644 --- a/src/backend/postmaster/walwriter.c +++ b/src/backend/postmaster/walwriter.c @@ -319,27 +319,21 @@ WalWriterMain(void) static void wal_quickdie(SIGNAL_ARGS) { - PG_SETMASK(&BlockSig); - /* - * We DO NOT want to run proc_exit() callbacks -- we're here because - * shared memory may be corrupted, so we don't want to try to clean up our - * transaction. Just nail the windows shut and get out of town. Now that - * there's an atexit callback to prevent third-party code from breaking - * things by calling exit() directly, we have to reset the callbacks - * explicitly to make this work as intended. - */ - on_exit_reset(); - - /* - * Note we do exit(2) not exit(0). This is to force the postmaster into a - * system reset cycle if some idiot DBA sends a manual SIGQUIT to a random + * We DO NOT want to run proc_exit() or atexit() callbacks -- we're here + * because shared memory may be corrupted, so we don't want to try to + * clean up our transaction. Just nail the windows shut and get out of + * town. The callbacks wouldn't be safe to run from a signal handler, + * anyway. + * + * Note we do _exit(2) not _exit(0). This is to force the postmaster into + * a system reset cycle if someone sends a manual SIGQUIT to a random * backend. This is necessary precisely because we don't clean up our * shared memory state. (The "dead man switch" mechanism in pmsignal.c * should ensure the postmaster sees this as a crash, too, but no harm in * being doubly sure.) */ - exit(2); + _exit(2); } /* SIGHUP: set flag to re-read config file at next convenient time */ diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c index 987bb84683c..c463c119eff 100644 --- a/src/backend/replication/walreceiver.c +++ b/src/backend/replication/walreceiver.c @@ -860,27 +860,21 @@ WalRcvShutdownHandler(SIGNAL_ARGS) static void WalRcvQuickDieHandler(SIGNAL_ARGS) { - PG_SETMASK(&BlockSig); - /* - * We DO NOT want to run proc_exit() callbacks -- we're here because - * shared memory may be corrupted, so we don't want to try to clean up our - * transaction. Just nail the windows shut and get out of town. Now that - * there's an atexit callback to prevent third-party code from breaking - * things by calling exit() directly, we have to reset the callbacks - * explicitly to make this work as intended. + * We DO NOT want to run proc_exit() or atexit() callbacks -- we're here + * because shared memory may be corrupted, so we don't want to try to + * clean up our transaction. Just nail the windows shut and get out of + * town. The callbacks wouldn't be safe to run from a signal handler, + * anyway. + * + * Note we use _exit(2) not _exit(0). This is to force the postmaster + * into a system reset cycle if someone sends a manual SIGQUIT to a + * random backend. This is necessary precisely because we don't clean up + * our shared memory state. (The "dead man switch" mechanism in + * pmsignal.c should ensure the postmaster sees this as a crash, too, but + * no harm in being doubly sure.) */ - on_exit_reset(); - - /* - * Note we do exit(2) not exit(0). This is to force the postmaster into a - * system reset cycle if some idiot DBA sends a manual SIGQUIT to a random - * backend. This is necessary precisely because we don't clean up our - * shared memory state. (The "dead man switch" mechanism in pmsignal.c - * should ensure the postmaster sees this as a crash, too, but no harm in - * being doubly sure.) - */ - exit(2); + _exit(2); } /* diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index f4133953beb..07b956553a7 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -2616,6 +2616,16 @@ quickdie(SIGNAL_ARGS) whereToSendOutput = DestNone; /* + * Notify the client before exiting, to give a clue on what happened. + * + * It's dubious to call ereport() from a signal handler. It is certainly + * not async-signal safe. But it seems better to try, than to disconnect + * abruptly and leave the client wondering what happened. It's remotely + * possible that we crash or hang while trying to send the message, but + * receiving a SIGQUIT is a sign that something has already gone badly + * wrong, so there's not much to lose. Assuming the postmaster is still + * running, it will SIGKILL us soon if we get stuck for some reason. + * * Ideally this should be ereport(FATAL), but then we'd not get control * back... */ @@ -2630,24 +2640,20 @@ quickdie(SIGNAL_ARGS) " database and repeat your command."))); /* - * We DO NOT want to run proc_exit() callbacks -- we're here because - * shared memory may be corrupted, so we don't want to try to clean up our - * transaction. Just nail the windows shut and get out of town. Now that - * there's an atexit callback to prevent third-party code from breaking - * things by calling exit() directly, we have to reset the callbacks - * explicitly to make this work as intended. - */ - on_exit_reset(); - - /* - * Note we do exit(2) not exit(0). This is to force the postmaster into a - * system reset cycle if some idiot DBA sends a manual SIGQUIT to a random + * We DO NOT want to run proc_exit() or atexit() callbacks -- we're here + * because shared memory may be corrupted, so we don't want to try to + * clean up our transaction. Just nail the windows shut and get out of + * town. The callbacks wouldn't be safe to run from a signal handler, + * anyway. + * + * Note we do _exit(2) not _exit(0). This is to force the postmaster into + * a system reset cycle if someone sends a manual SIGQUIT to a random * backend. This is necessary precisely because we don't clean up our * shared memory state. (The "dead man switch" mechanism in pmsignal.c * should ensure the postmaster sees this as a crash, too, but no harm in * being doubly sure.) */ - exit(2); + _exit(2); } /*