diff options
Diffstat (limited to 'src/backend/libpq/pqmq.c')
| -rw-r--r-- | src/backend/libpq/pqmq.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/src/backend/libpq/pqmq.c b/src/backend/libpq/pqmq.c index 9ca6b7ce0d..0a3c2b70cb 100644 --- a/src/backend/libpq/pqmq.c +++ b/src/backend/libpq/pqmq.c @@ -26,6 +26,7 @@ static bool pq_mq_busy = false; static pid_t pq_mq_parallel_master_pid = 0; static pid_t pq_mq_parallel_master_backend_id = InvalidBackendId; +static void pq_cleanup_redirect_to_shm_mq(dsm_segment *seg, Datum arg); static void mq_comm_reset(void); static int mq_flush(void); static int mq_flush_if_writable(void); @@ -51,13 +52,26 @@ static PQcommMethods PqCommMqMethods = { * message queue. */ void -pq_redirect_to_shm_mq(shm_mq *mq, shm_mq_handle *mqh) +pq_redirect_to_shm_mq(dsm_segment *seg, shm_mq_handle *mqh) { PqCommMethods = &PqCommMqMethods; - pq_mq = mq; + pq_mq = shm_mq_get_queue(mqh); pq_mq_handle = mqh; whereToSendOutput = DestRemote; FrontendProtocol = PG_PROTOCOL_LATEST; + on_dsm_detach(seg, pq_cleanup_redirect_to_shm_mq, (Datum) 0); +} + +/* + * When the DSM that contains our shm_mq goes away, we need to stop sending + * messages to it. + */ +static void +pq_cleanup_redirect_to_shm_mq(dsm_segment *seg, Datum arg) +{ + pq_mq = NULL; + pq_mq_handle = NULL; + whereToSendOutput = DestNone; } /* @@ -123,9 +137,19 @@ mq_putmessage(char msgtype, const char *s, size_t len) if (pq_mq != NULL) shm_mq_detach(pq_mq); pq_mq = NULL; + pq_mq_handle = NULL; return EOF; } + /* + * If the message queue is already gone, just ignore the message. This + * doesn't necessarily indicate a problem; for example, DEBUG messages + * can be generated late in the shutdown sequence, after all DSMs have + * already been detached. + */ + if (pq_mq == NULL) + return 0; + pq_mq_busy = true; iov[0].data = &msgtype; |