diff options
Diffstat (limited to 'src/backend/tcop/postgres.c')
| -rw-r--r-- | src/backend/tcop/postgres.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index 6200699ddd7..dd2ade7bb65 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -554,7 +554,7 @@ ProcessClientWriteInterrupt(bool blocked) { /* * Don't mess with whereToSendOutput if ProcessInterrupts wouldn't - * do anything. + * service ProcDiePending. */ if (InterruptHoldoffCount == 0 && CritSectionCount == 0) { @@ -3118,6 +3118,12 @@ RecoveryConflictInterrupt(ProcSignalReason reason) * If an interrupt condition is pending, and it's safe to service it, * then clear the flag and accept the interrupt. Called only when * InterruptPending is true. + * + * Note: if INTERRUPTS_CAN_BE_PROCESSED() is true, then ProcessInterrupts + * is guaranteed to clear the InterruptPending flag before returning. + * (This is not the same as guaranteeing that it's still clear when we + * return; another interrupt could have arrived. But we promise that + * any pre-existing one will have been serviced.) */ void ProcessInterrupts(void) @@ -3248,7 +3254,11 @@ ProcessInterrupts(void) { /* * Re-arm InterruptPending so that we process the cancel request as - * soon as we're done reading the message. + * soon as we're done reading the message. (XXX this is seriously + * ugly: it complicates INTERRUPTS_CAN_BE_PROCESSED(), and it means we + * can't use that macro directly as the initial test in this function, + * meaning that this code also creates opportunities for other bugs to + * appear.) */ InterruptPending = true; } |