diff options
| author | Amit Kapila | 2022-11-14 05:13:33 +0000 |
|---|---|---|
| committer | Amit Kapila | 2022-11-14 05:13:33 +0000 |
| commit | e848be60b5cf9a883765ea8e98c411e7fef0c1c6 (patch) | |
| tree | 34f07f9350093afd8df02a7b9461b175d243c4f1 /src/backend | |
| parent | ad6c52846f13e4e86daa247c1369ed85558830e7 (diff) | |
Fix cleanup lock acquisition in SPLIT_ALLOCATE_PAGE replay.
During XLOG_HASH_SPLIT_ALLOCATE_PAGE replay, we were checking for a
cleanup lock on the new bucket page after acquiring an exclusive lock on
it and raising a PANIC error on failure. However, it is quite possible
that checkpointer can acquire the pin on the same page before acquiring a
lock on it, and then the replay will lead to an error. So instead, directly
acquire the cleanup lock on the new bucket page during
XLOG_HASH_SPLIT_ALLOCATE_PAGE replay operation.
Reported-by: Andres Freund
Author: Robert Haas
Reviewed-By: Amit Kapila, Andres Freund, Vignesh C
Backpatch-through: 11
Discussion: https://postgr.es/m/20220810022617.fvjkjiauaykwrbse@awork3.anarazel.de
Diffstat (limited to 'src/backend')
| -rw-r--r-- | src/backend/access/hash/hash_xlog.c | 5 | ||||
| -rw-r--r-- | src/backend/access/hash/hashpage.c | 10 |
2 files changed, 9 insertions, 6 deletions
diff --git a/src/backend/access/hash/hash_xlog.c b/src/backend/access/hash/hash_xlog.c index e88213c7425..a24a1c39081 100644 --- a/src/backend/access/hash/hash_xlog.c +++ b/src/backend/access/hash/hash_xlog.c @@ -351,11 +351,10 @@ hash_xlog_split_allocate_page(XLogReaderState *record) } /* replay the record for new bucket */ - newbuf = XLogInitBufferForRedo(record, 1); + XLogReadBufferForRedoExtended(record, 1, RBM_ZERO_AND_CLEANUP_LOCK, true, + &newbuf); _hash_initbuf(newbuf, xlrec->new_bucket, xlrec->new_bucket, xlrec->new_bucket_flag, true); - if (!IsBufferCleanupOK(newbuf)) - elog(PANIC, "hash_xlog_split_allocate_page: failed to acquire cleanup lock"); MarkBufferDirty(newbuf); PageSetLSN(BufferGetPage(newbuf), lsn); diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c index d2edcd46172..55b2929ad51 100644 --- a/src/backend/access/hash/hashpage.c +++ b/src/backend/access/hash/hashpage.c @@ -805,9 +805,13 @@ restart_expand: /* * Physically allocate the new bucket's primary page. We want to do this * before changing the metapage's mapping info, in case we can't get the - * disk space. Ideally, we don't need to check for cleanup lock on new - * bucket as no other backend could find this bucket unless meta page is - * updated. However, it is good to be consistent with old bucket locking. + * disk space. + * + * XXX It doesn't make sense to call _hash_getnewbuf first, zeroing the + * buffer, and then only afterwards check whether we have a cleanup lock. + * However, since no scan can be accessing the buffer yet, any concurrent + * accesses will just be from processes like the bgwriter or checkpointer + * which don't care about its contents, so it doesn't really matter. */ buf_nblkno = _hash_getnewbuf(rel, start_nblkno, MAIN_FORKNUM); if (!IsBufferCleanupOK(buf_nblkno)) |