On Mon, Dec 5, 2016 at 2:46 AM, Amit Kapila <amit.kapil...@gmail.com> wrote:
>> I'll review after that, since I have other things to review meanwhile.
>
> Attached, please find the rebased patch attached with this e-mail.
> There is no fundamental change in patch except for adapting the new
> locking strategy in squeeze operation. I have done the sanity testing
> of the patch with master-standby setup and Kuntal has helped me to
> verify it with his wal-consistency checker patch.
This patch again needs a rebase, but before you do that I'd like to
make it harder by applying the attached patch to remove
_hash_chgbufaccess(), which I think is a bad plan for more or less the
same reasons that motivated the removal of _hash_wrtbuf() in commit
25216c98938495fd741bf585dcbef45b3a9ffd40. I think there's probably
more simplification and cleanup that can be done afterward in the wake
of this; what I've done here is just a mechanical replacement of
_hash_chgbufaccess() with LockBuffer() and/or MarkBufferDirty(). The
point is that having MarkBufferDirty() calls happen implicitly instead
some other function is not what we want for write-ahead logging. Your
patch gets rid of that, too; this is just doing it somewhat more
thoroughly.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
diff --git a/src/backend/access/hash/hash.c b/src/backend/access/hash/hash.c
index 0eeb37d..1fa087a 100644
--- a/src/backend/access/hash/hash.c
+++ b/src/backend/access/hash/hash.c
@@ -274,7 +274,7 @@ hashgettuple(IndexScanDesc scan, ScanDirection dir)
* Reacquire the read lock here.
*/
if (BufferIsValid(so->hashso_curbuf))
- _hash_chgbufaccess(rel, so->hashso_curbuf, HASH_NOLOCK, HASH_READ);
+ LockBuffer(so->hashso_curbuf, BUFFER_LOCK_SHARE);
/*
* If we've already initialized this scan, we can just advance it in the
@@ -354,7 +354,7 @@ hashgettuple(IndexScanDesc scan, ScanDirection dir)
/* Release read lock on current buffer, but keep it pinned */
if (BufferIsValid(so->hashso_curbuf))
- _hash_chgbufaccess(rel, so->hashso_curbuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(so->hashso_curbuf, BUFFER_LOCK_UNLOCK);
/* Return current heap TID on success */
scan->xs_ctup.t_self = so->hashso_heappos;
@@ -524,7 +524,7 @@ hashbulkdelete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
orig_ntuples = metap->hashm_ntuples;
memcpy(&local_metapage, metap, sizeof(local_metapage));
/* release the lock, but keep pin */
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
/* Scan the buckets that we know exist */
cur_bucket = 0;
@@ -576,9 +576,9 @@ loop_top:
* (and thus can't be further split), update our cached metapage
* data.
*/
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_READ);
+ LockBuffer(metabuf, BUFFER_LOCK_SHARE);
memcpy(&local_metapage, metap, sizeof(local_metapage));
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
}
bucket_buf = buf;
@@ -597,7 +597,7 @@ loop_top:
}
/* Write-lock metapage and check for split since we started */
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(metabuf, BUFFER_LOCK_EXCLUSIVE);
metap = HashPageGetMeta(BufferGetPage(metabuf));
if (cur_maxbucket != metap->hashm_maxbucket)
@@ -605,7 +605,7 @@ loop_top:
/* There's been a split, so process the additional bucket(s) */
cur_maxbucket = metap->hashm_maxbucket;
memcpy(&local_metapage, metap, sizeof(local_metapage));
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
goto loop_top;
}
@@ -821,7 +821,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf,
* page
*/
if (retain_pin)
- _hash_chgbufaccess(rel, buf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(buf, BUFFER_LOCK_UNLOCK);
else
_hash_relbuf(rel, buf);
@@ -836,7 +836,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf,
if (buf != bucket_buf)
{
_hash_relbuf(rel, buf);
- _hash_chgbufaccess(rel, bucket_buf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(bucket_buf, BUFFER_LOCK_EXCLUSIVE);
}
/*
@@ -866,7 +866,7 @@ hashbucketcleanup(Relation rel, Bucket cur_bucket, Buffer bucket_buf,
_hash_squeezebucket(rel, cur_bucket, bucket_blkno, bucket_buf,
bstrategy);
else
- _hash_chgbufaccess(rel, bucket_buf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(bucket_buf, BUFFER_LOCK_UNLOCK);
}
void
diff --git a/src/backend/access/hash/hashinsert.c b/src/backend/access/hash/hashinsert.c
index 59c4213..b51b487 100644
--- a/src/backend/access/hash/hashinsert.c
+++ b/src/backend/access/hash/hashinsert.c
@@ -102,7 +102,7 @@ restart_insert:
lowmask = metap->hashm_lowmask;
/* Release metapage lock, but keep pin. */
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
/*
* If the previous iteration of this loop locked the primary page of
@@ -123,7 +123,7 @@ restart_insert:
* Reacquire metapage lock and check that no bucket split has taken
* place while we were awaiting the bucket lock.
*/
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_READ);
+ LockBuffer(metabuf, BUFFER_LOCK_SHARE);
oldblkno = blkno;
retry = true;
}
@@ -147,7 +147,7 @@ restart_insert:
if (H_BUCKET_BEING_SPLIT(pageopaque) && IsBufferCleanupOK(buf))
{
/* release the lock on bucket buffer, before completing the split. */
- _hash_chgbufaccess(rel, buf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(buf, BUFFER_LOCK_UNLOCK);
_hash_finish_split(rel, metabuf, buf, pageopaque->hasho_bucket,
maxbucket, highmask, lowmask);
@@ -178,7 +178,7 @@ restart_insert:
if (buf != bucket_buf)
_hash_relbuf(rel, buf);
else
- _hash_chgbufaccess(rel, buf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(buf, BUFFER_LOCK_UNLOCK);
buf = _hash_getbuf(rel, nextblkno, HASH_WRITE, LH_OVERFLOW_PAGE);
page = BufferGetPage(buf);
}
@@ -190,7 +190,7 @@ restart_insert:
*/
/* release our write lock without modifying buffer */
- _hash_chgbufaccess(rel, buf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(buf, BUFFER_LOCK_UNLOCK);
/* chain to a new overflow page */
buf = _hash_addovflpage(rel, metabuf, buf, (buf == bucket_buf) ? true : false);
@@ -221,7 +221,7 @@ restart_insert:
* Write-lock the metapage so we can increment the tuple count. After
* incrementing it, check to see if it's time for a split.
*/
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(metabuf, BUFFER_LOCK_EXCLUSIVE);
metap->hashm_ntuples += 1;
@@ -230,7 +230,8 @@ restart_insert:
(double) metap->hashm_ffactor * (metap->hashm_maxbucket + 1);
/* Write out the metapage and drop lock, but keep pin */
- _hash_chgbufaccess(rel, metabuf, HASH_WRITE, HASH_NOLOCK);
+ MarkBufferDirty(metabuf);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
/* Attempt to split if a split is needed */
if (do_expand)
diff --git a/src/backend/access/hash/hashovfl.c b/src/backend/access/hash/hashovfl.c
index df7838c..6b106f3 100644
--- a/src/backend/access/hash/hashovfl.c
+++ b/src/backend/access/hash/hashovfl.c
@@ -110,7 +110,7 @@ _hash_addovflpage(Relation rel, Buffer metabuf, Buffer buf, bool retain_pin)
* Write-lock the tail page. It is okay to hold two buffer locks here
* since there cannot be anyone else contending for access to ovflbuf.
*/
- _hash_chgbufaccess(rel, buf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
/* probably redundant... */
_hash_checkpage(rel, buf, LH_BUCKET_PAGE | LH_OVERFLOW_PAGE);
@@ -129,7 +129,7 @@ _hash_addovflpage(Relation rel, Buffer metabuf, Buffer buf, bool retain_pin)
/* we assume we do not need to write the unmodified page */
if ((pageopaque->hasho_flag & LH_BUCKET_PAGE) && retain_pin)
- _hash_chgbufaccess(rel, buf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(buf, BUFFER_LOCK_UNLOCK);
else
_hash_relbuf(rel, buf);
@@ -151,7 +151,7 @@ _hash_addovflpage(Relation rel, Buffer metabuf, Buffer buf, bool retain_pin)
pageopaque->hasho_nextblkno = BufferGetBlockNumber(ovflbuf);
MarkBufferDirty(buf);
if ((pageopaque->hasho_flag & LH_BUCKET_PAGE) && retain_pin)
- _hash_chgbufaccess(rel, buf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(buf, BUFFER_LOCK_UNLOCK);
else
_hash_relbuf(rel, buf);
@@ -187,7 +187,7 @@ _hash_getovflpage(Relation rel, Buffer metabuf)
j;
/* Get exclusive lock on the meta page */
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(metabuf, BUFFER_LOCK_EXCLUSIVE);
_hash_checkpage(rel, metabuf, LH_META_PAGE);
metap = HashPageGetMeta(BufferGetPage(metabuf));
@@ -225,7 +225,7 @@ _hash_getovflpage(Relation rel, Buffer metabuf)
last_inpage = BMPGSZ_BIT(metap) - 1;
/* Release exclusive lock on metapage while reading bitmap page */
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
mapbuf = _hash_getbuf(rel, mapblkno, HASH_WRITE, LH_BITMAP_PAGE);
mappage = BufferGetPage(mapbuf);
@@ -244,7 +244,7 @@ _hash_getovflpage(Relation rel, Buffer metabuf)
bit = 0;
/* Reacquire exclusive lock on the meta page */
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(metabuf, BUFFER_LOCK_EXCLUSIVE);
}
/*
@@ -295,7 +295,8 @@ _hash_getovflpage(Relation rel, Buffer metabuf)
metap->hashm_firstfree = bit + 1;
/* Write updated metapage and release lock, but not pin */
- _hash_chgbufaccess(rel, metabuf, HASH_WRITE, HASH_NOLOCK);
+ MarkBufferDirty(metabuf);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
return newbuf;
@@ -309,7 +310,7 @@ found:
_hash_relbuf(rel, mapbuf);
/* Reacquire exclusive lock on the meta page */
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(metabuf, BUFFER_LOCK_EXCLUSIVE);
/* convert bit to absolute bit number */
bit += (i << BMPG_SHIFT(metap));
@@ -326,12 +327,13 @@ found:
metap->hashm_firstfree = bit + 1;
/* Write updated metapage and release lock, but not pin */
- _hash_chgbufaccess(rel, metabuf, HASH_WRITE, HASH_NOLOCK);
+ MarkBufferDirty(metabuf);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
}
else
{
/* We didn't change the metapage, so no need to write */
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
}
/* Fetch, init, and return the recycled page */
@@ -483,7 +485,7 @@ _hash_freeovflpage(Relation rel, Buffer ovflbuf, Buffer wbuf,
blkno = metap->hashm_mapp[bitmappage];
/* Release metapage lock while we access the bitmap page */
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
/* Clear the bitmap bit to indicate that this overflow page is free */
mapbuf = _hash_getbuf(rel, blkno, HASH_WRITE, LH_BITMAP_PAGE);
@@ -495,7 +497,7 @@ _hash_freeovflpage(Relation rel, Buffer ovflbuf, Buffer wbuf,
_hash_relbuf(rel, mapbuf);
/* Get write-lock on metapage to update firstfree */
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(metabuf, BUFFER_LOCK_EXCLUSIVE);
/* if this is now the first free page, update hashm_firstfree */
if (ovflbitno < metap->hashm_firstfree)
@@ -633,7 +635,7 @@ _hash_squeezebucket(Relation rel,
*/
if (!BlockNumberIsValid(wopaque->hasho_nextblkno))
{
- _hash_chgbufaccess(rel, wbuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(wbuf, BUFFER_LOCK_UNLOCK);
return;
}
@@ -721,7 +723,7 @@ _hash_squeezebucket(Relation rel,
if (wbuf_dirty)
MarkBufferDirty(wbuf);
if (retain_pin)
- _hash_chgbufaccess(rel, wbuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(wbuf, BUFFER_LOCK_UNLOCK);
else
_hash_relbuf(rel, wbuf);
@@ -784,7 +786,7 @@ _hash_squeezebucket(Relation rel,
{
/* retain the pin on primary bucket page till end of bucket scan */
if (wblkno == bucket_blkno)
- _hash_chgbufaccess(rel, wbuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(wbuf, BUFFER_LOCK_UNLOCK);
else
_hash_relbuf(rel, wbuf);
return;
diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c
index a3d2138..45e184c 100644
--- a/src/backend/access/hash/hashpage.c
+++ b/src/backend/access/hash/hashpage.c
@@ -289,32 +289,6 @@ _hash_dropscanbuf(Relation rel, HashScanOpaque so)
so->hashso_buc_split = false;
}
-/*
- * _hash_chgbufaccess() -- Change the lock type on a buffer, without
- * dropping our pin on it.
- *
- * from_access and to_access may be HASH_READ, HASH_WRITE, or HASH_NOLOCK,
- * the last indicating that no buffer-level lock is held or wanted.
- *
- * When from_access == HASH_WRITE, we assume the buffer is dirty and tell
- * bufmgr it must be written out. If the caller wants to release a write
- * lock on a page that's not been modified, it's okay to pass from_access
- * as HASH_READ (a bit ugly, but handy in some places).
- */
-void
-_hash_chgbufaccess(Relation rel,
- Buffer buf,
- int from_access,
- int to_access)
-{
- if (from_access == HASH_WRITE)
- MarkBufferDirty(buf);
- if (from_access != HASH_NOLOCK)
- LockBuffer(buf, BUFFER_LOCK_UNLOCK);
- if (to_access != HASH_NOLOCK)
- LockBuffer(buf, to_access);
-}
-
/*
* _hash_metapinit() -- Initialize the metadata page of a hash index,
@@ -446,7 +420,8 @@ _hash_metapinit(Relation rel, double num_tuples, ForkNumber forkNum)
* won't accomplish anything. It's a bad idea to hold buffer locks for
* long intervals in any case, since that can block the bgwriter.
*/
- _hash_chgbufaccess(rel, metabuf, HASH_WRITE, HASH_NOLOCK);
+ MarkBufferDirty(metabuf);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
/*
* Initialize the first N buckets
@@ -469,7 +444,7 @@ _hash_metapinit(Relation rel, double num_tuples, ForkNumber forkNum)
}
/* Now reacquire buffer lock on metapage */
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(metabuf, BUFFER_LOCK_EXCLUSIVE);
/*
* Initialize first bitmap page
@@ -528,7 +503,7 @@ restart_expand:
* Write-lock the meta page. It used to be necessary to acquire a
* heavyweight lock to begin a split, but that is no longer required.
*/
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(metabuf, BUFFER_LOCK_EXCLUSIVE);
_hash_checkpage(rel, metabuf, LH_META_PAGE);
metap = HashPageGetMeta(BufferGetPage(metabuf));
@@ -609,8 +584,8 @@ restart_expand:
* Release the lock on metapage and old_bucket, before completing the
* split.
*/
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
- _hash_chgbufaccess(rel, buf_oblkno, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
+ LockBuffer(buf_oblkno, BUFFER_LOCK_UNLOCK);
_hash_finish_split(rel, metabuf, buf_oblkno, old_bucket, maxbucket,
highmask, lowmask);
@@ -646,7 +621,7 @@ restart_expand:
lowmask = metap->hashm_lowmask;
/* Release the metapage lock. */
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
hashbucketcleanup(rel, old_bucket, buf_oblkno, start_oblkno, NULL,
maxbucket, highmask, lowmask, NULL, NULL, true,
@@ -753,7 +728,8 @@ restart_expand:
lowmask = metap->hashm_lowmask;
/* Write out the metapage and drop lock, but keep pin */
- _hash_chgbufaccess(rel, metabuf, HASH_WRITE, HASH_NOLOCK);
+ MarkBufferDirty(metabuf);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
/* Relocate records to the new bucket */
_hash_splitbucket(rel, metabuf,
@@ -767,7 +743,7 @@ restart_expand:
fail:
/* We didn't write the metapage, so just drop lock */
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
}
@@ -1001,7 +977,8 @@ _hash_splitbucket_guts(Relation rel,
if (PageGetFreeSpace(npage) < itemsz)
{
/* write out nbuf and drop lock, but keep pin */
- _hash_chgbufaccess(rel, nbuf, HASH_WRITE, HASH_NOLOCK);
+ MarkBufferDirty(nbuf);
+ LockBuffer(nbuf, BUFFER_LOCK_UNLOCK);
/* chain to a new overflow page */
nbuf = _hash_addovflpage(rel, metabuf, nbuf, (nbuf == bucket_nbuf) ? true : false);
npage = BufferGetPage(nbuf);
@@ -1033,7 +1010,7 @@ _hash_splitbucket_guts(Relation rel,
/* retain the pin on the old primary bucket */
if (obuf == bucket_obuf)
- _hash_chgbufaccess(rel, obuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(obuf, BUFFER_LOCK_UNLOCK);
else
_hash_relbuf(rel, obuf);
@@ -1056,18 +1033,21 @@ _hash_splitbucket_guts(Relation rel,
* bucket and then the new bucket.
*/
if (nbuf == bucket_nbuf)
- _hash_chgbufaccess(rel, bucket_nbuf, HASH_WRITE, HASH_NOLOCK);
+ {
+ MarkBufferDirty(bucket_nbuf);
+ LockBuffer(bucket_nbuf, BUFFER_LOCK_UNLOCK);
+ }
else
{
MarkBufferDirty(nbuf);
_hash_relbuf(rel, nbuf);
}
- _hash_chgbufaccess(rel, bucket_obuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(bucket_obuf, BUFFER_LOCK_EXCLUSIVE);
opage = BufferGetPage(bucket_obuf);
oopaque = (HashPageOpaque) PageGetSpecialPointer(opage);
- _hash_chgbufaccess(rel, bucket_nbuf, HASH_NOLOCK, HASH_WRITE);
+ LockBuffer(bucket_nbuf, BUFFER_LOCK_EXCLUSIVE);
npage = BufferGetPage(bucket_nbuf);
nopaque = (HashPageOpaque) PageGetSpecialPointer(npage);
@@ -1172,7 +1152,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket,
* retain the pin on primary bucket.
*/
if (nbuf == bucket_nbuf)
- _hash_chgbufaccess(rel, nbuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(nbuf, BUFFER_LOCK_UNLOCK);
else
_hash_relbuf(rel, nbuf);
@@ -1194,7 +1174,7 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket,
}
if (!ConditionalLockBufferForCleanup(bucket_nbuf))
{
- _hash_chgbufaccess(rel, obuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(obuf, BUFFER_LOCK_UNLOCK);
hash_destroy(tidhtab);
return;
}
@@ -1208,6 +1188,6 @@ _hash_finish_split(Relation rel, Buffer metabuf, Buffer obuf, Bucket obucket,
maxbucket, highmask, lowmask);
_hash_relbuf(rel, bucket_nbuf);
- _hash_chgbufaccess(rel, obuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(obuf, BUFFER_LOCK_UNLOCK);
hash_destroy(tidhtab);
}
diff --git a/src/backend/access/hash/hashsearch.c b/src/backend/access/hash/hashsearch.c
index 8d43b38..913b87c 100644
--- a/src/backend/access/hash/hashsearch.c
+++ b/src/backend/access/hash/hashsearch.c
@@ -83,7 +83,7 @@ _hash_readnext(IndexScanDesc scan,
* comments in _hash_first to know the reason of retaining pin.
*/
if (*bufp == so->hashso_bucket_buf || *bufp == so->hashso_split_bucket_buf)
- _hash_chgbufaccess(rel, *bufp, HASH_READ, HASH_NOLOCK);
+ LockBuffer(*bufp, BUFFER_LOCK_UNLOCK);
else
_hash_relbuf(rel, *bufp);
@@ -109,7 +109,7 @@ _hash_readnext(IndexScanDesc scan,
*/
Assert(BufferIsValid(*bufp));
- _hash_chgbufaccess(rel, *bufp, HASH_NOLOCK, HASH_READ);
+ LockBuffer(*bufp, BUFFER_LOCK_SHARE);
/*
* setting hashso_buc_split to true indicates that we are scanning
@@ -147,7 +147,7 @@ _hash_readprev(IndexScanDesc scan,
* comments in _hash_first to know the reason of retaining pin.
*/
if (*bufp == so->hashso_bucket_buf || *bufp == so->hashso_split_bucket_buf)
- _hash_chgbufaccess(rel, *bufp, HASH_READ, HASH_NOLOCK);
+ LockBuffer(*bufp, BUFFER_LOCK_UNLOCK);
else
_hash_relbuf(rel, *bufp);
@@ -182,7 +182,7 @@ _hash_readprev(IndexScanDesc scan,
*/
Assert(BufferIsValid(*bufp));
- _hash_chgbufaccess(rel, *bufp, HASH_NOLOCK, HASH_READ);
+ LockBuffer(*bufp, BUFFER_LOCK_SHARE);
*pagep = BufferGetPage(*bufp);
*opaquep = (HashPageOpaque) PageGetSpecialPointer(*pagep);
@@ -298,7 +298,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir)
blkno = BUCKET_TO_BLKNO(metap, bucket);
/* Release metapage lock, but keep pin. */
- _hash_chgbufaccess(rel, metabuf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
/*
* If the previous iteration of this loop locked what is still the
@@ -319,7 +319,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir)
* Reacquire metapage lock and check that no bucket split has taken
* place while we were awaiting the bucket lock.
*/
- _hash_chgbufaccess(rel, metabuf, HASH_NOLOCK, HASH_READ);
+ LockBuffer(metabuf, BUFFER_LOCK_SHARE);
oldblkno = blkno;
retry = true;
}
@@ -359,7 +359,7 @@ _hash_first(IndexScanDesc scan, ScanDirection dir)
* release the lock on new bucket and re-acquire it after acquiring
* the lock on old bucket.
*/
- _hash_chgbufaccess(rel, buf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(buf, BUFFER_LOCK_UNLOCK);
old_buf = _hash_getbuf(rel, old_blkno, HASH_READ, LH_BUCKET_PAGE);
@@ -368,9 +368,9 @@ _hash_first(IndexScanDesc scan, ScanDirection dir)
* scanning.
*/
so->hashso_split_bucket_buf = old_buf;
- _hash_chgbufaccess(rel, old_buf, HASH_READ, HASH_NOLOCK);
+ LockBuffer(old_buf, BUFFER_LOCK_UNLOCK);
- _hash_chgbufaccess(rel, buf, HASH_NOLOCK, HASH_READ);
+ LockBuffer(buf, BUFFER_LOCK_SHARE);
page = BufferGetPage(buf);
opaque = (HashPageOpaque) PageGetSpecialPointer(page);
Assert(opaque->hasho_bucket == bucket);
diff --git a/src/include/access/hash.h b/src/include/access/hash.h
index 627fa2c..bc08f81 100644
--- a/src/include/access/hash.h
+++ b/src/include/access/hash.h
@@ -336,8 +336,6 @@ extern Buffer _hash_getbuf_with_strategy(Relation rel, BlockNumber blkno,
extern void _hash_relbuf(Relation rel, Buffer buf);
extern void _hash_dropbuf(Relation rel, Buffer buf);
extern void _hash_dropscanbuf(Relation rel, HashScanOpaque so);
-extern void _hash_chgbufaccess(Relation rel, Buffer buf, int from_access,
- int to_access);
extern uint32 _hash_metapinit(Relation rel, double num_tuples,
ForkNumber forkNum);
extern void _hash_pageinit(Page page, Size size);
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