diff options
| author | Peter Eisentraut <peter@eisentraut.org> | 2020-03-26 11:51:39 +0100 |
|---|---|---|
| committer | Peter Eisentraut <peter@eisentraut.org> | 2020-03-26 13:51:22 +0100 |
| commit | f36a10434a31bdf6298071c1ddf8d151d103d9fa (patch) | |
| tree | 8fd4fa48d513d5d90f9214983c28fa9724595251 /src | |
| parent | 2060999a4d6e4b946a3f032bdd3df1c55ac855b3 (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
Diffstat (limited to 'src')
| -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 d59c5488c7f..137e9f5dc52 100644 --- a/src/backend/replication/slot.c +++ b/src/backend/replication/slot.c @@ -1251,6 +1251,12 @@ 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", @@ -1282,6 +1288,7 @@ SaveSlotToPath(ReplicationSlot *slot, const char *dir, int elevel) pgstat_report_wait_end(); 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; @@ -1301,6 +1308,7 @@ SaveSlotToPath(ReplicationSlot *slot, const char *dir, int elevel) pgstat_report_wait_end(); CloseTransientFile(fd); + LWLockRelease(&slot->io_in_progress_lock); errno = save_errno; ereport(elevel, (errcode_for_file_access(), @@ -1315,6 +1323,7 @@ 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", |