Refactor XLogOpenRelation() and XLogReadBuffer() in preparation for relation

forks. XLogOpenRelation() and the associated light-weight relation cache in
xlogutils.c is gone, and XLogReadBuffer() now takes a RelFileNode as argument,
instead of Relation.

For functions that still need a Relation struct during WAL replay, there's a
new function called CreateFakeRelcacheEntry() that returns a fake entry like
XLogOpenRelation() used to.

Author: hlinnaka

src/backend/access/gin/ginxlog.c

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *			 $PostgreSQL: pgsql/src/backend/access/gin/ginxlog.c,v 1.13 2008/05/12 00:00:44 alvherre Exp $
+ *			 $PostgreSQL: pgsql/src/backend/access/gin/ginxlog.c,v 1.14 2008/06/12 09:12:29 heikki Exp $
  *-------------------------------------------------------------------------
  */
 #include "postgres.h"
@@ -71,12 +71,10 @@ static void
 ginRedoCreateIndex(XLogRecPtr lsn, XLogRecord *record)
 {
 	RelFileNode *node = (RelFileNode *) XLogRecGetData(record);
-	Relation	reln;
 	Buffer		buffer;
 	Page		page;
 
-	reln = XLogOpenRelation(*node);
-	buffer = XLogReadBuffer(reln, GIN_ROOT_BLKNO, true);
+	buffer = XLogReadBuffer(*node, GIN_ROOT_BLKNO, true);
 	Assert(BufferIsValid(buffer));
 	page = (Page) BufferGetPage(buffer);
 
@@ -94,12 +92,10 @@ ginRedoCreatePTree(XLogRecPtr lsn, XLogRecord *record)
 {
 	ginxlogCreatePostingTree *data = (ginxlogCreatePostingTree *) XLogRecGetData(record);
 	ItemPointerData *items = (ItemPointerData *) (XLogRecGetData(record) + sizeof(ginxlogCreatePostingTree));
-	Relation	reln;
 	Buffer		buffer;
 	Page		page;
 
-	reln = XLogOpenRelation(data->node);
-	buffer = XLogReadBuffer(reln, data->blkno, true);
+	buffer = XLogReadBuffer(data->node, data->blkno, true);
 	Assert(BufferIsValid(buffer));
 	page = (Page) BufferGetPage(buffer);
 
@@ -118,16 +114,14 @@ static void
 ginRedoInsert(XLogRecPtr lsn, XLogRecord *record)
 {
 	ginxlogInsert *data = (ginxlogInsert *) XLogRecGetData(record);
-	Relation	reln;
 	Buffer		buffer;
 	Page		page;
 
 	/* nothing else to do if page was backed up */
 	if (record->xl_info & XLR_BKP_BLOCK_1)
 		return;
 
-	reln = XLogOpenRelation(data->node);
-	buffer = XLogReadBuffer(reln, data->blkno, false);
+	buffer = XLogReadBuffer(data->node, data->blkno, false);
 	Assert(BufferIsValid(buffer));
 	page = (Page) BufferGetPage(buffer);
 
@@ -228,26 +222,23 @@ static void
 ginRedoSplit(XLogRecPtr lsn, XLogRecord *record)
 {
 	ginxlogSplit *data = (ginxlogSplit *) XLogRecGetData(record);
-	Relation	reln;
 	Buffer		lbuffer,
 				rbuffer;
 	Page		lpage,
 				rpage;
 	uint32		flags = 0;
 
-	reln = XLogOpenRelation(data->node);
-
 	if (data->isLeaf)
 		flags |= GIN_LEAF;
 	if (data->isData)
 		flags |= GIN_DATA;
 
-	lbuffer = XLogReadBuffer(reln, data->lblkno, data->isRootSplit);
+	lbuffer = XLogReadBuffer(data->node, data->lblkno, data->isRootSplit);
 	Assert(BufferIsValid(lbuffer));
 	lpage = (Page) BufferGetPage(lbuffer);
 	GinInitBuffer(lbuffer, flags);
 
-	rbuffer = XLogReadBuffer(reln, data->rblkno, true);
+	rbuffer = XLogReadBuffer(data->node, data->rblkno, true);
 	Assert(BufferIsValid(rbuffer));
 	rpage = (Page) BufferGetPage(rbuffer);
 	GinInitBuffer(rbuffer, flags);
@@ -319,7 +310,7 @@ ginRedoSplit(XLogRecPtr lsn, XLogRecord *record)
 
 	if (data->isRootSplit)
 	{
-		Buffer		rootBuf = XLogReadBuffer(reln, data->rootBlkno, false);
+		Buffer		rootBuf = XLogReadBuffer(data->node, data->rootBlkno, false);
 		Page		rootPage = BufferGetPage(rootBuf);
 
 		GinInitBuffer(rootBuf, flags & ~GIN_LEAF);
@@ -352,16 +343,14 @@ static void
 ginRedoVacuumPage(XLogRecPtr lsn, XLogRecord *record)
 {
 	ginxlogVacuumPage *data = (ginxlogVacuumPage *) XLogRecGetData(record);
-	Relation	reln;
 	Buffer		buffer;
 	Page		page;
 
 	/* nothing else to do if page was backed up (and no info to do it with) */
 	if (record->xl_info & XLR_BKP_BLOCK_1)
 		return;
 
-	reln = XLogOpenRelation(data->node);
-	buffer = XLogReadBuffer(reln, data->blkno, false);
+	buffer = XLogReadBuffer(data->node, data->blkno, false);
 	Assert(BufferIsValid(buffer));
 	page = (Page) BufferGetPage(buffer);
 
@@ -403,15 +392,12 @@ static void
 ginRedoDeletePage(XLogRecPtr lsn, XLogRecord *record)
 {
 	ginxlogDeletePage *data = (ginxlogDeletePage *) XLogRecGetData(record);
-	Relation	reln;
 	Buffer		buffer;
 	Page		page;
 
-	reln = XLogOpenRelation(data->node);
-
 	if (!(record->xl_info & XLR_BKP_BLOCK_1))
 	{
-		buffer = XLogReadBuffer(reln, data->blkno, false);
+		buffer = XLogReadBuffer(data->node, data->blkno, false);
 		page = BufferGetPage(buffer);
 		Assert(GinPageIsData(page));
 		GinPageGetOpaque(page)->flags = GIN_DELETED;
@@ -423,7 +409,7 @@ ginRedoDeletePage(XLogRecPtr lsn, XLogRecord *record)
 
 	if (!(record->xl_info & XLR_BKP_BLOCK_2))
 	{
-		buffer = XLogReadBuffer(reln, data->parentBlkno, false);
+		buffer = XLogReadBuffer(data->node, data->parentBlkno, false);
 		page = BufferGetPage(buffer);
 		Assert(GinPageIsData(page));
 		Assert(!GinPageIsLeaf(page));
@@ -436,7 +422,7 @@ ginRedoDeletePage(XLogRecPtr lsn, XLogRecord *record)
 
 	if (!(record->xl_info & XLR_BKP_BLOCK_3) && data->leftBlkno != InvalidBlockNumber)
 	{
-		buffer = XLogReadBuffer(reln, data->leftBlkno, false);
+		buffer = XLogReadBuffer(data->node, data->leftBlkno, false);
 		page = BufferGetPage(buffer);
 		Assert(GinPageIsData(page));
 		GinPageGetOpaque(page)->rightlink = data->rightLink;
@@ -557,9 +543,9 @@ ginContinueSplit(ginIncompleteSplit *split)
 	 * elog(NOTICE,"ginContinueSplit root:%u l:%u r:%u",  split->rootBlkno,
 	 * split->leftBlkno, split->rightBlkno);
 	 */
-	reln = XLogOpenRelation(split->node);
+	buffer = XLogReadBuffer(split->node, split->leftBlkno, false);
 
-	buffer = XLogReadBuffer(reln, split->leftBlkno, false);
+	reln = CreateFakeRelcacheEntry(split->node);
 
 	if (split->rootBlkno == GIN_ROOT_BLKNO)
 	{
@@ -581,6 +567,8 @@ ginContinueSplit(ginIncompleteSplit *split)
 									   GinPageGetOpaque(page)->maxoff))->key;
 	}
 
+	FreeFakeRelcacheEntry(reln);
+
 	btree.rightblkno = split->rightBlkno;
 
 	stack.blkno = split->leftBlkno;

src/backend/access/gist/gist.c

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/gist/gist.c,v 1.150 2008/05/12 00:00:44 alvherre Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/gist/gist.c,v 1.151 2008/06/12 09:12:29 heikki Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -462,7 +462,7 @@ gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
 
 		if (!is_leaf)
 			PageIndexTupleDelete(state->stack->page, state->stack->childoffnum);
-		gistfillbuffer(state->r, state->stack->page, state->itup, state->ituplen, InvalidOffsetNumber);
+		gistfillbuffer(state->stack->page, state->itup, state->ituplen, InvalidOffsetNumber);
 
 		MarkBufferDirty(state->stack->buffer);
 
@@ -1008,7 +1008,7 @@ gistnewroot(Relation r, Buffer buffer, IndexTuple *itup, int len, ItemPointer ke
 	START_CRIT_SECTION();
 
 	GISTInitBuffer(buffer, 0);
-	gistfillbuffer(r, page, itup, len, FirstOffsetNumber);
+	gistfillbuffer(page, itup, len, FirstOffsetNumber);
 
 	MarkBufferDirty(buffer);
 

src/backend/access/gist/gistutil.c

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *			$PostgreSQL: pgsql/src/backend/access/gist/gistutil.c,v 1.26 2008/05/12 00:00:44 alvherre Exp $
+ *			$PostgreSQL: pgsql/src/backend/access/gist/gistutil.c,v 1.27 2008/06/12 09:12:29 heikki Exp $
  *-------------------------------------------------------------------------
  */
 #include "postgres.h"
@@ -27,11 +27,10 @@ static Datum attrS[INDEX_MAX_KEYS];
 static bool isnullS[INDEX_MAX_KEYS];
 
 /*
- * Write itup vector to page, has no control of free space
+ * Write itup vector to page, has no control of free space.
  */
-OffsetNumber
-gistfillbuffer(Relation r, Page page, IndexTuple *itup,
-			   int len, OffsetNumber off)
+void
+gistfillbuffer(Page page, IndexTuple *itup, int len, OffsetNumber off)
 {
 	OffsetNumber l = InvalidOffsetNumber;
 	int			i;
@@ -42,14 +41,13 @@ gistfillbuffer(Relation r, Page page, IndexTuple *itup,
 
 	for (i = 0; i < len; i++)
 	{
-		l = PageAddItem(page, (Item) itup[i], IndexTupleSize(itup[i]),
-						off, false, false);
+		Size sz = IndexTupleSize(itup[i]);
+		l = PageAddItem(page, (Item) itup[i], sz, off, false, false);
 		if (l == InvalidOffsetNumber)
-			elog(ERROR, "failed to add item to index page in \"%s\"",
-				 RelationGetRelationName(r));
+			elog(ERROR, "failed to add item to GiST index page, item %d out of %d, size %d bytes",
+				 i, len, sz);
 		off++;
 	}
-	return l;
 }
 
 /*

src/backend/access/gist/gistvacuum.c

@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/gist/gistvacuum.c,v 1.35 2008/05/12 00:00:44 alvherre Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/gist/gistvacuum.c,v 1.36 2008/06/12 09:12:30 heikki Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -403,7 +403,7 @@ gistVacuumUpdate(GistVacuum *gv, BlockNumber blkno, bool needunion)
 			}
 			else
 				/* enough free space */
-				gistfillbuffer(gv->index, tempPage, addon, curlenaddon, InvalidOffsetNumber);
+				gistfillbuffer(tempPage, addon, curlenaddon, InvalidOffsetNumber);
 		}
 	}