Remove unnecessary variables in _hash_splitbucket().

Commit ed9cc2b5df59fdbc50cce37399e26b03ab2c1686 made it unnecessary to pass
start_nblkno to _hash_splitbucket(), and for that matter unnecessary to
have the internal nblkno variable either.  My compiler didn't complain
about that, but some did.  I also rearranged the use of oblkno a bit to
make that case more parallel.

Report and initial patch by Petr Jelinek, rearranged a bit by me.
Back-patch to all branches, like the previous patch.

diff --git a/src/backend/access/hash/hashpage.c b/src/backend/access/hash/hashpage.c
index 72d2029b32ec5e03a4bd65f18b4cac794075a07a..38682ad91fd57b694b6db98a50521528e000bae9 100644 (file)
--- a/src/backend/access/hash/hashpage.c
+++ b/src/backend/access/hash/hashpage.c
@@ -37,10 +37,9 @@
 static bool _hash_alloc_buckets(Relation rel, BlockNumber firstblock,
                                        uint32 nblocks);
 static void _hash_splitbucket(Relation rel, Buffer metabuf,
-                                 Buffer nbuf,
                                  Bucket obucket, Bucket nbucket,
                                  BlockNumber start_oblkno,
-                                 BlockNumber start_nblkno,
+                                 Buffer nbuf,
                                  uint32 maxbucket,
                                  uint32 highmask, uint32 lowmask);
 
@@ -679,9 +678,9 @@ _hash_expandtable(Relation rel, Buffer metabuf)
        _hash_droplock(rel, 0, HASH_EXCLUSIVE);
 
        /* Relocate records to the new bucket */
-       _hash_splitbucket(rel, metabuf, buf_nblkno,
+       _hash_splitbucket(rel, metabuf,
                                          old_bucket, new_bucket,
-                                         start_oblkno, start_nblkno,
+                                         start_oblkno, buf_nblkno,
                                          maxbucket, highmask, lowmask);
 
        /* Release bucket locks, allowing others to access them */
@@ -765,24 +764,22 @@ _hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks)
  * touched if it becomes necessary to add or remove overflow pages.)
  *
  * In addition, the caller must have created the new bucket's base page,
- * which is passed in buffer nbuf, pinned and write-locked.  The lock
- * and pin are released here.  (The API is set up this way because we must
- * do _hash_getnewbuf() before releasing the metapage write lock.)
+ * which is passed in buffer nbuf, pinned and write-locked.  That lock and
+ * pin are released here.  (The API is set up this way because we must do
+ * _hash_getnewbuf() before releasing the metapage write lock.  So instead of
+ * passing the new bucket's start block number, we pass an actual buffer.)
  */
 static void
 _hash_splitbucket(Relation rel,
                                  Buffer metabuf,
-                                 Buffer nbuf,
                                  Bucket obucket,
                                  Bucket nbucket,
                                  BlockNumber start_oblkno,
-                                 BlockNumber start_nblkno,
+                                 Buffer nbuf,
                                  uint32 maxbucket,
                                  uint32 highmask,
                                  uint32 lowmask)
 {
-       BlockNumber oblkno;
-       BlockNumber nblkno;
        Buffer          obuf;
        Page            opage;
        Page            npage;
@@ -794,13 +791,10 @@ _hash_splitbucket(Relation rel,
         * since no one else can be trying to acquire buffer lock on pages of
         * either bucket.
         */
-       oblkno = start_oblkno;
-       obuf = _hash_getbuf(rel, oblkno, HASH_WRITE, LH_BUCKET_PAGE);
+       obuf = _hash_getbuf(rel, start_oblkno, HASH_WRITE, LH_BUCKET_PAGE);
        opage = BufferGetPage(obuf);
        oopaque = (HashPageOpaque) PageGetSpecialPointer(opage);
 
-       nblkno = start_nblkno;
-       Assert(nblkno == BufferGetBlockNumber(nbuf));
        npage = BufferGetPage(nbuf);
 
        /* initialize the new bucket's primary page */
@@ -819,6 +813,7 @@ _hash_splitbucket(Relation rel,
         */
        for (;;)
        {
+               BlockNumber oblkno;
                OffsetNumber ooffnum;
                OffsetNumber omaxoffnum;
                OffsetNumber deletable[MaxOffsetNumber];
@@ -865,7 +860,7 @@ _hash_splitbucket(Relation rel,
                                        /* chain to a new overflow page */
                                        nbuf = _hash_addovflpage(rel, metabuf, nbuf);
                                        npage = BufferGetPage(nbuf);
-                                       /* we don't need nblkno or nopaque within the loop */
+                                       /* we don't need nopaque within the loop */
                                }
 
                                /*