diff options
Diffstat (limited to 'src/backend/libpq/pqmq.c')
| -rw-r--r-- | src/backend/libpq/pqmq.c | 33 |
1 files changed, 32 insertions, 1 deletions
diff --git a/src/backend/libpq/pqmq.c b/src/backend/libpq/pqmq.c index 307fb60665c..f12f2d582e8 100644 --- a/src/backend/libpq/pqmq.c +++ b/src/backend/libpq/pqmq.c @@ -16,12 +16,15 @@ #include "libpq/libpq.h" #include "libpq/pqformat.h" #include "libpq/pqmq.h" +#include "miscadmin.h" #include "tcop/tcopprot.h" #include "utils/builtins.h" static shm_mq *pq_mq; static shm_mq_handle *pq_mq_handle; 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 mq_comm_reset(void); static int mq_flush(void); @@ -57,6 +60,18 @@ pq_redirect_to_shm_mq(shm_mq *mq, shm_mq_handle *mqh) FrontendProtocol = PG_PROTOCOL_LATEST; } +/* + * Arrange to SendProcSignal() to the parallel master each time we transmit + * message data via the shm_mq. + */ +void +pq_set_parallel_master(pid_t pid, BackendId backend_id) +{ + Assert(PqCommMethods == &PqCommMqMethods); + pq_mq_parallel_master_pid = pid; + pq_mq_parallel_master_backend_id = backend_id; +} + static void mq_comm_reset(void) { @@ -120,7 +135,23 @@ mq_putmessage(char msgtype, const char *s, size_t len) iov[1].len = len; Assert(pq_mq_handle != NULL); - result = shm_mq_sendv(pq_mq_handle, iov, 2, false); + + for (;;) + { + result = shm_mq_sendv(pq_mq_handle, iov, 2, true); + + if (pq_mq_parallel_master_pid != 0) + SendProcSignal(pq_mq_parallel_master_pid, + PROCSIG_PARALLEL_MESSAGE, + pq_mq_parallel_master_backend_id); + + if (result != SHM_MQ_WOULD_BLOCK) + break; + + WaitLatch(&MyProc->procLatch, WL_LATCH_SET, 0); + CHECK_FOR_INTERRUPTS(); + ResetLatch(&MyProc->procLatch); + } pq_mq_busy = false; |