diff options
| author | Peter Eisentraut <peter@eisentraut.org> | 2020-03-26 11:51:39 +0100 |
|---|---|---|
| committer | Peter Eisentraut <peter@eisentraut.org> | 2020-03-26 14:01:56 +0100 |
| commit | 2d8597ba66a1646e353c0ff755b4b0b85cd1747f (patch) | |
| tree | cc849609d96b9457f2f62710addbeae7e1769fcb | |
| parent | ef7f01a50489efdf5f6fd2f352853d2deb6c3e5e (diff) | |
Drop slot's LWLock before returning from SaveSlotToPath()
When SaveSlotToPath() is called with elevel=LOG, the early exits didn't
release the slot's io_in_progress_lock.
This could result in a walsender being stuck on the lock forever. A
possible way to get into this situation is if the offending code paths
are triggered in a low disk space situation.
Author: Pavan Deolasee <pavan.deolasee@2ndquadrant.com>
Reported-by: Craig Ringer <craig@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/56a138c5-de61-f553-7e8f-6789296de785%402ndquadrant.com
| -rw-r--r-- | src/backend/replication/slot.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c index 61c65213171..ce08f90695e 100644 --- a/src/backend/replication/slot.c +++ b/src/backend/replication/slot.c @@ -1062,6 +1062,12 @@ SaveSlotToPath(ReplicationSlot *slot, const char *dir, int elevel) S_IRUSR | S_IWUSR); if (fd < 0) { + /* + * If not an ERROR, then release the lock before returning. In case + * of an ERROR, the error recovery path automatically releases the + * lock, but no harm in explicitly releasing even in that case. + */ + LWLockRelease(&slot->io_in_progress_lock); ereport(elevel, (errcode_for_file_access(), errmsg("could not create file \"%s\": %m", @@ -1091,6 +1097,7 @@ SaveSlotToPath(ReplicationSlot *slot, const char *dir, int elevel) int save_errno = errno; CloseTransientFile(fd); + LWLockRelease(&slot->io_in_progress_lock); /* if write didn't set errno, assume problem is no disk space */ errno = save_errno ? save_errno : ENOSPC; @@ -1107,6 +1114,7 @@ SaveSlotToPath(ReplicationSlot *slot, const char *dir, int elevel) int save_errno = errno; CloseTransientFile(fd); + LWLockRelease(&slot->io_in_progress_lock); errno = save_errno; ereport(elevel, (errcode_for_file_access(), @@ -1120,6 +1128,7 @@ SaveSlotToPath(ReplicationSlot *slot, const char *dir, int elevel) /* rename to permanent file, fsync file and directory */ if (rename(tmppath, path) != 0) { + LWLockRelease(&slot->io_in_progress_lock); ereport(elevel, (errcode_for_file_access(), errmsg("could not rename file \"%s\" to \"%s\": %m", |