diff options
Diffstat (limited to 'src/backend/access/nbtree')
| -rw-r--r-- | src/backend/access/nbtree/nbtpage.c | 34 | ||||
| -rw-r--r-- | src/backend/access/nbtree/nbtree.c | 3 |
2 files changed, 12 insertions, 25 deletions
diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c index 0144c3ab571..41aa1c4ccd1 100644 --- a/src/backend/access/nbtree/nbtpage.c +++ b/src/backend/access/nbtree/nbtpage.c @@ -882,7 +882,6 @@ _bt_getbuf(Relation rel, Relation heaprel, BlockNumber blkno, int access) } else { - bool needLock; Page page; Assert(access == BT_WRITE); @@ -963,31 +962,16 @@ _bt_getbuf(Relation rel, Relation heaprel, BlockNumber blkno, int access) } /* - * Extend the relation by one page. - * - * We have to use a lock to ensure no one else is extending the rel at - * the same time, else we will both try to initialize the same new - * page. We can skip locking for new or temp relations, however, - * since no one else could be accessing them. - */ - needLock = !RELATION_IS_LOCAL(rel); - - if (needLock) - LockRelationForExtension(rel, ExclusiveLock); - - buf = ReadBuffer(rel, P_NEW); - - /* Acquire buffer lock on new page */ - _bt_lockbuf(rel, buf, BT_WRITE); - - /* - * Release the file-extension lock; it's now OK for someone else to - * extend the relation some more. Note that we cannot release this - * lock before we have buffer lock on the new page, or we risk a race - * condition against btvacuumscan --- see comments therein. + * Extend the relation by one page. Need to use RBM_ZERO_AND_LOCK or + * we risk a race condition against btvacuumscan --- see comments + * therein. This forces us to repeat the valgrind request that + * _bt_lockbuf() otherwise would make, as we can't use _bt_lockbuf() + * without introducing a race. */ - if (needLock) - UnlockRelationForExtension(rel, ExclusiveLock); + buf = ExtendBufferedRel(EB_REL(rel), MAIN_FORKNUM, NULL, + EB_LOCK_FIRST); + if (!RelationUsesLocalBuffers(rel)) + VALGRIND_MAKE_MEM_DEFINED(BufferGetPage(buf), BLCKSZ); /* Initialize the new page before returning it */ page = BufferGetPage(buf); diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c index 409a2c12100..992f84834f8 100644 --- a/src/backend/access/nbtree/nbtree.c +++ b/src/backend/access/nbtree/nbtree.c @@ -970,6 +970,9 @@ btvacuumscan(IndexVacuumInfo *info, IndexBulkDeleteResult *stats, * write-lock on the left page before it adds a right page, so we must * already have processed any tuples due to be moved into such a page. * + * XXX: Now that new pages are locked with RBM_ZERO_AND_LOCK, I don't + * think the use of the extension lock is still required. + * * We can skip locking for new or temp relations, however, since no one * else could be accessing them. */ |