diff options
| author | Thomas Munro | 2021-03-01 03:28:12 +0000 |
|---|---|---|
| committer | Thomas Munro | 2021-03-01 04:24:47 +0000 |
| commit | f5a5773a9dc4185414fe538525e20d8512c2ba35 (patch) | |
| tree | 1ccd54e64409d6197720f5e8fa64cccae5addc95 | |
| parent | 814f1d8bc395bb9b4c0ae090ceea60adfbeb8e49 (diff) | |
Allow condition variables to be used in interrupt code.
Adjust the condition variable sleep loop to work correctly when code
reached by its internal CHECK_FOR_INTERRUPTS() call interacts with
another condition variable.
There are no such cases currently, but a proposed patch would do this.
Discussion: https://postgr.es/m/CA+hUKGLdemy2gBm80kz20GTe6hNVwoErE8KwcJk6-U56oStjtg@mail.gmail.com
| -rw-r--r-- | src/backend/storage/lmgr/condition_variable.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/src/backend/storage/lmgr/condition_variable.c b/src/backend/storage/lmgr/condition_variable.c index 0a61ff0031f..80d70c154cf 100644 --- a/src/backend/storage/lmgr/condition_variable.c +++ b/src/backend/storage/lmgr/condition_variable.c @@ -165,8 +165,6 @@ ConditionVariableTimedSleep(ConditionVariable *cv, long timeout, /* Reset latch before examining the state of the wait list. */ ResetLatch(MyLatch); - CHECK_FOR_INTERRUPTS(); - /* * If this process has been taken out of the wait list, then we know * that it has been signaled by ConditionVariableSignal (or @@ -190,6 +188,15 @@ ConditionVariableTimedSleep(ConditionVariable *cv, long timeout, } SpinLockRelease(&cv->mutex); + /* + * Check for interrupts, and return spuriously if that caused the + * current sleep target to change (meaning that interrupt handler code + * waited for a different condition variable). + */ + CHECK_FOR_INTERRUPTS(); + if (cv != cv_sleep_target) + done = true; + /* We were signaled, so return */ if (done) return false; |