diff options
| author | Robert Haas | 2017-04-04 02:24:17 +0000 |
|---|---|---|
| committer | Robert Haas | 2017-04-04 02:26:06 +0000 |
| commit | 93cd7684ee2bba227fa371daa81b88f25456dcb2 (patch) | |
| tree | 269f3d373f1708887a8aa6866c18720e43292e56 | |
| parent | f5780935266bd72951c770396f9267366414d1b9 (diff) | |
Properly acquire buffer lock for page-at-a-time hash vacuum.
In a couple of places, _hash_kill_items was mistakenly called with
the buffer lock not held. Repair.
Ashutosh Sharma, per a report from Andreas Seltenreich
Discussion: http://postgr.es/m/[email protected]
| -rw-r--r-- | src/backend/access/hash/hash.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/src/backend/access/hash/hash.c b/src/backend/access/hash/hash.c index 34cc08f12d..b835f772d4 100644 --- a/src/backend/access/hash/hash.c +++ b/src/backend/access/hash/hash.c @@ -476,9 +476,17 @@ hashrescan(IndexScanDesc scan, ScanKey scankey, int nscankeys, HashScanOpaque so = (HashScanOpaque) scan->opaque; Relation rel = scan->indexRelation; - /* Before leaving current page, deal with any killed items */ + /* + * Before leaving current page, deal with any killed items. + * Also, ensure that we acquire lock on current page before + * calling _hash_kill_items. + */ if (so->numKilled > 0) + { + LockBuffer(so->hashso_curbuf, BUFFER_LOCK_SHARE); _hash_kill_items(scan); + LockBuffer(so->hashso_curbuf, BUFFER_LOCK_UNLOCK); + } _hash_dropscanbuf(rel, so); @@ -507,9 +515,17 @@ hashendscan(IndexScanDesc scan) HashScanOpaque so = (HashScanOpaque) scan->opaque; Relation rel = scan->indexRelation; - /* Before leaving current page, deal with any killed items */ + /* + * Before leaving current page, deal with any killed items. + * Also, ensure that we acquire lock on current page before + * calling _hash_kill_items. + */ if (so->numKilled > 0) + { + LockBuffer(so->hashso_curbuf, BUFFER_LOCK_SHARE); _hash_kill_items(scan); + LockBuffer(so->hashso_curbuf, BUFFER_LOCK_UNLOCK); + } _hash_dropscanbuf(rel, so); |