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| author | Thomas Munro <tmunro@postgresql.org> | 2019-06-21 10:57:07 +1200 |
|---|---|---|
| committer | Thomas Munro <tmunro@postgresql.org> | 2019-06-21 10:57:07 +1200 |
| commit | 25b93a2967a4ebfb90168ca087026cc697fc4b77 (patch) | |
| tree | 391379ff6932634cf6ff903795d338a39245927e /src | |
| parent | 20e1cc898da6f82b5680973c107e8a96d46caf01 (diff) | |
| download | postgresql-25b93a2967a4ebfb90168ca087026cc697fc4b77.tar.gz postgresql-25b93a2967a4ebfb90168ca087026cc697fc4b77.zip | |
Remove obsolete comments about sempahores from proc.c.
Commit 6753333f switched from a semaphore-based wait to a latch-based
wait for ProcSleep()/ProcWakeup(), but left behind some stray references
to semaphores.
Back-patch to 9.5.
Reviewed-by: Daniel Gustafsson, Michael Paquier
Discussion: https://postgr.es/m/CA+hUKGLs5H6zhmgTijZ1OaJvC1sG0=AFXc1aHuce32tKiQrdEA@mail.gmail.com
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/storage/lmgr/proc.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c index 0da5b19719f..498373fd0ee 100644 --- a/src/backend/storage/lmgr/proc.c +++ b/src/backend/storage/lmgr/proc.c @@ -1196,8 +1196,7 @@ ProcSleep(LOCALLOCK *locallock, LockMethod lockMethodTable) /* * If we detected deadlock, give up without waiting. This must agree with - * CheckDeadLock's recovery code, except that we shouldn't release the - * semaphore since we haven't tried to lock it yet. + * CheckDeadLock's recovery code. */ if (early_deadlock) { @@ -1233,9 +1232,9 @@ ProcSleep(LOCALLOCK *locallock, LockMethod lockMethodTable) /* * Set timer so we can wake up after awhile and check for a deadlock. If a - * deadlock is detected, the handler releases the process's semaphore and - * sets MyProc->waitStatus = STATUS_ERROR, allowing us to know that we - * must report failure rather than success. + * deadlock is detected, the handler sets MyProc->waitStatus = + * STATUS_ERROR, allowing us to know that we must report failure rather + * than success. * * By delaying the check until we've waited for a bit, we can avoid * running the rather expensive deadlock-check code in most cases. @@ -1578,7 +1577,7 @@ ProcSleep(LOCALLOCK *locallock, LockMethod lockMethodTable) /* - * ProcWakeup -- wake up a process by releasing its private semaphore. + * ProcWakeup -- wake up a process by setting its latch. * * Also remove the process from the wait queue and set its links invalid. * RETURN: the next process in the wait queue. @@ -1713,8 +1712,7 @@ CheckDeadLock(void) * we know that we don't have to wait anymore. * * We check by looking to see if we've been unlinked from the wait queue. - * This is quicker than checking our semaphore's state, since no kernel - * call is needed, and it is safe because we hold the lock partition lock. + * This is safe because we hold the lock partition lock. */ if (MyProc->links.prev == NULL || MyProc->links.next == NULL) |