Change SearchSysCache coding conventions so that a reference count is

maintained for each cache entry.  A cache entry will not be freed until
the matching ReleaseSysCache call has been executed.  This eliminates
worries about cache entries getting dropped while still in use.  See
my posting to pg-hackers of even date for more info.

5 files changed, 76 insertions, 84 deletions

diff --git a/src/backend/access/common/printtup.c b/src/backend/access/common/printtup.c
index 6fe0e9652c2..ccf3071b502 100644
--- a/src/backend/access/common/printtup.c
+++ b/src/backend/access/common/printtup.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/common/printtup.c,v 1.53 2000/05/30 04:24:27 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/common/printtup.c,v 1.54 2000/11/16 22:30:15 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -36,7 +36,7 @@ static void printtup_cleanup(DestReceiver *self);
  *		getTypeOutAndElem -- get both typoutput and typelem for a type
  *
  * We used to fetch these with two separate function calls,
- * typtoout() and gettypelem(), which each called SearchSysCacheTuple.
+ * typtoout() and gettypelem(), which each called SearchSysCache.
  * This way takes half the time.
  * ----------------
  */
@@ -44,25 +44,19 @@ int
 getTypeOutAndElem(Oid type, Oid *typOutput, Oid *typElem)
 {
 	HeapTuple	typeTuple;
-
-	typeTuple = SearchSysCacheTuple(TYPEOID,
-									ObjectIdGetDatum(type),
-									0, 0, 0);
-
-	if (HeapTupleIsValid(typeTuple))
-	{
-		Form_pg_type pt = (Form_pg_type) GETSTRUCT(typeTuple);
-
-		*typOutput = (Oid) pt->typoutput;
-		*typElem = (Oid) pt->typelem;
-		return OidIsValid(*typOutput);
-	}
-
-	elog(ERROR, "getTypeOutAndElem: Cache lookup of type %u failed", type);
-
-	*typOutput = InvalidOid;
-	*typElem = InvalidOid;
-	return 0;
+	Form_pg_type pt;
+
+	typeTuple = SearchSysCache(TYPEOID,
+							   ObjectIdGetDatum(type),
+							   0, 0, 0);
+	if (!HeapTupleIsValid(typeTuple))
+		elog(ERROR, "getTypeOutAndElem: Cache lookup of type %u failed", type);
+	pt = (Form_pg_type) GETSTRUCT(typeTuple);
+
+	*typOutput = pt->typoutput;
+	*typElem = pt->typelem;
+	ReleaseSysCache(typeTuple);
+	return OidIsValid(*typOutput);
 }
 
 /* ----------------
diff --git a/src/backend/access/common/tupdesc.c b/src/backend/access/common/tupdesc.c
index 1ed2366efda..8b9b7cd537f 100644
--- a/src/backend/access/common/tupdesc.c
+++ b/src/backend/access/common/tupdesc.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/common/tupdesc.c,v 1.68 2000/11/08 22:09:53 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/common/tupdesc.c,v 1.69 2000/11/16 22:30:15 tgl Exp $
  *
  * NOTES
  *	  some of the executor utility code such as "ExecTypeFromTL" should be
@@ -401,9 +401,9 @@ TupleDescInitEntry(TupleDesc desc,
 	 *	-cim 6/14/90
 	 * ----------------
 	 */
-	tuple = SearchSysCacheTuple(TYPEOID,
-								ObjectIdGetDatum(oidtypeid),
-								0, 0, 0);
+	tuple = SearchSysCache(TYPEOID,
+						   ObjectIdGetDatum(oidtypeid),
+						   0, 0, 0);
 	if (!HeapTupleIsValid(tuple))
 	{
 		/* ----------------
@@ -455,25 +455,18 @@ TupleDescInitEntry(TupleDesc desc,
 	   */
 	if (attisset)
 	{
-		Type		t = typeidType(OIDOID);
-
-		att->attlen = typeLen(t);
-		att->attbyval = typeByVal(t);
+		att->attlen = sizeof(Oid);
+		att->attbyval = true;
+		att->attstorage = 'p';
 	}
 	else
 	{
 		att->attlen = typeForm->typlen;
 		att->attbyval = typeForm->typbyval;
-/*
- * Default to the types storage
- */
-#ifdef TUPLE_TOASTER_ACTIVE
 		att->attstorage = typeForm->typstorage;
-#else
-		att->attstorage = 'p';
-#endif
 	}
 
+	ReleaseSysCache(tuple);
 
 	return true;
 }
@@ -496,12 +489,11 @@ TupleDescMakeSelfReference(TupleDesc desc,
 						   char *relname)
 {
 	Form_pg_attribute att;
-	Type		t = typeidType(OIDOID);
 
 	att = desc->attrs[attnum - 1];
 	att->atttypid = TypeShellMake(relname);
-	att->attlen = typeLen(t);
-	att->attbyval = typeByVal(t);
+	att->attlen = sizeof(Oid);
+	att->attbyval = true;
 	att->attstorage = 'p';
 	att->attnelems = 0;
 }
@@ -580,7 +572,7 @@ BuildDescForRelation(List *schema, char *relname)
 		}
 
 		if (!TupleDescInitEntry(desc, attnum, attname,
-								typeTypeId(typenameType(typename)),
+								typenameTypeId(typename),
 								atttypmod, attdim, attisset))
 		{
 			/* ----------------
diff --git a/src/backend/access/gist/gist.c b/src/backend/access/gist/gist.c
index d7bfeb1287d..d8e9005e933 100644
--- a/src/backend/access/gist/gist.c
+++ b/src/backend/access/gist/gist.c
@@ -6,7 +6,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/gist/gist.c,v 1.64 2000/11/08 22:09:53 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/gist/gist.c,v 1.65 2000/11/16 22:30:15 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1140,6 +1140,7 @@ initGISTstate(GISTSTATE *giststate, Relation index)
 				equal_proc;
 	HeapTuple	htup;
 	Form_pg_index itupform;
+	Oid			indexrelid;
 
 	consistent_proc = index_getprocid(index, 1, GIST_CONSISTENT_PROC);
 	union_proc = index_getprocid(index, 1, GIST_UNION_PROC);
@@ -1157,32 +1158,32 @@ initGISTstate(GISTSTATE *giststate, Relation index)
 	fmgr_info(equal_proc, &giststate->equalFn);
 
 	/* see if key type is different from type of attribute being indexed */
-	htup = SearchSysCacheTuple(INDEXRELID,
-							   ObjectIdGetDatum(RelationGetRelid(index)),
-							   0, 0, 0);
-	itupform = (Form_pg_index) GETSTRUCT(htup);
+	htup = SearchSysCache(INDEXRELID,
+						  ObjectIdGetDatum(RelationGetRelid(index)),
+						  0, 0, 0);
 	if (!HeapTupleIsValid(htup))
 		elog(ERROR, "initGISTstate: index %u not found",
 			 RelationGetRelid(index));
+	itupform = (Form_pg_index) GETSTRUCT(htup);
 	giststate->haskeytype = itupform->indhaskeytype;
+	indexrelid = itupform->indexrelid;
+	ReleaseSysCache(htup);
+
 	if (giststate->haskeytype)
 	{
 		/* key type is different -- is it byval? */
-		htup = SearchSysCacheTuple(ATTNUM,
-								   ObjectIdGetDatum(itupform->indexrelid),
-								   UInt16GetDatum(FirstOffsetNumber),
-								   0, 0);
+		htup = SearchSysCache(ATTNUM,
+							  ObjectIdGetDatum(indexrelid),
+							  UInt16GetDatum(FirstOffsetNumber),
+							  0, 0);
 		if (!HeapTupleIsValid(htup))
-		{
 			elog(ERROR, "initGISTstate: no attribute tuple %u %d",
-				 itupform->indexrelid, FirstOffsetNumber);
-			return;
-		}
+				 indexrelid, FirstOffsetNumber);
 		giststate->keytypbyval = (((Form_pg_attribute) htup)->attbyval);
+		ReleaseSysCache(htup);
 	}
 	else
 		giststate->keytypbyval = FALSE;
-	return;
 }
 
 
diff --git a/src/backend/access/index/istrat.c b/src/backend/access/index/istrat.c
index d6a966bcd44..681b80e1e86 100644
--- a/src/backend/access/index/istrat.c
+++ b/src/backend/access/index/istrat.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/index/Attic/istrat.c,v 1.46 2000/07/14 22:17:30 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/index/Attic/istrat.c,v 1.47 2000/11/16 22:30:16 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -482,9 +482,9 @@ OperatorRelationFillScanKeyEntry(Relation operatorRelation,
 
 	if (cachesearch)
 	{
-		tuple = SearchSysCacheTuple(OPEROID,
-									ObjectIdGetDatum(operatorObjectId),
-									0, 0, 0);
+		tuple = SearchSysCache(OPEROID,
+							   ObjectIdGetDatum(operatorObjectId),
+							   0, 0, 0);
 	}
 	else
 	{
@@ -505,24 +505,25 @@ OperatorRelationFillScanKeyEntry(Relation operatorRelation,
 	{
 		if (!cachesearch)
 			heap_endscan(scan);
-		elog(ERROR, "OperatorObjectIdFillScanKeyEntry: unknown operator %u",
+		elog(ERROR, "OperatorRelationFillScanKeyEntry: unknown operator %u",
 			 operatorObjectId);
 	}
 
 	entry->sk_flags = 0;
 	entry->sk_procedure = ((Form_pg_operator) GETSTRUCT(tuple))->oprcode;
-	fmgr_info(entry->sk_procedure, &entry->sk_func);
-	entry->sk_nargs = entry->sk_func.fn_nargs;
 
-	if (!cachesearch)
+	if (cachesearch)
+		ReleaseSysCache(tuple);
+	else
 		heap_endscan(scan);
 
 	if (!RegProcedureIsValid(entry->sk_procedure))
-	{
 		elog(ERROR,
-		"OperatorObjectIdFillScanKeyEntry: no procedure for operator %u",
+			 "OperatorRelationFillScanKeyEntry: no procedure for operator %u",
 			 operatorObjectId);
-	}
+
+	fmgr_info(entry->sk_procedure, &entry->sk_func);
+	entry->sk_nargs = entry->sk_func.fn_nargs;
 }
 
 
@@ -547,16 +548,16 @@ IndexSupportInitialize(IndexStrategy indexStrategy,
 	HeapTuple	tuple;
 	Form_pg_index iform;
 	StrategyMap map;
-	AttrNumber	attributeNumber;
-	int			attributeIndex;
+	AttrNumber	attNumber;
+	int			attIndex;
 	Oid			operatorClassObjectId[INDEX_MAX_KEYS];
 	bool		cachesearch = (!IsBootstrapProcessingMode()) && IsCacheInitialized();
 
 	if (cachesearch)
 	{
-		tuple = SearchSysCacheTuple(INDEXRELID,
-									ObjectIdGetDatum(indexObjectId),
-									0, 0, 0);
+		tuple = SearchSysCache(INDEXRELID,
+							   ObjectIdGetDatum(indexObjectId),
+							   0, 0, 0);
 	}
 	else
 	{
@@ -583,19 +584,23 @@ IndexSupportInitialize(IndexStrategy indexStrategy,
 	 * XXX note that the following assumes the INDEX tuple is well formed
 	 * and that the *key and *class are 0 terminated.
 	 */
-	for (attributeIndex = 0; attributeIndex < maxAttributeNumber; attributeIndex++)
+	for (attIndex = 0; attIndex < maxAttributeNumber; attIndex++)
 	{
-		if (!OidIsValid(iform->indkey[attributeIndex]))
+		if (!OidIsValid(iform->indkey[attIndex]))
 		{
-			if (attributeIndex == InvalidAttrNumber)
+			if (attIndex == InvalidAttrNumber)
 				elog(ERROR, "IndexSupportInitialize: no pg_index tuple");
 			break;
 		}
 
-		operatorClassObjectId[attributeIndex] = iform->indclass[attributeIndex];
+		operatorClassObjectId[attIndex] = iform->indclass[attIndex];
 	}
 
-	if (!cachesearch)
+	if (cachesearch)
+	{
+		ReleaseSysCache(tuple);
+	}
+	else
 	{
 		heap_endscan(scan);
 		heap_close(relation, AccessShareLock);
@@ -614,20 +619,19 @@ IndexSupportInitialize(IndexStrategy indexStrategy,
 		relation = heap_openr(AccessMethodProcedureRelationName,
 							  AccessShareLock);
 
-		for (attributeNumber = 1; attributeNumber <= maxAttributeNumber;
-			 attributeNumber++)
+		for (attNumber = 1; attNumber <= maxAttributeNumber; attNumber++)
 		{
 			int16		support;
 			Form_pg_amproc aform;
 			RegProcedure *loc;
 
-			loc = &indexSupport[((attributeNumber - 1) * maxSupportNumber)];
+			loc = &indexSupport[((attNumber - 1) * maxSupportNumber)];
 
 			for (support = 0; support < maxSupportNumber; ++support)
 				loc[support] = InvalidOid;
 
 			entry[1].sk_argument =
-				ObjectIdGetDatum(operatorClassObjectId[attributeNumber - 1]);
+				ObjectIdGetDatum(operatorClassObjectId[attNumber - 1]);
 
 			scan = heap_beginscan(relation, false, SnapshotNow, 2, entry);
 
@@ -654,17 +658,16 @@ IndexSupportInitialize(IndexStrategy indexStrategy,
 	relation = heap_openr(AccessMethodOperatorRelationName, AccessShareLock);
 	operatorRelation = heap_openr(OperatorRelationName, AccessShareLock);
 
-	for (attributeNumber = maxAttributeNumber; attributeNumber > 0;
-		 attributeNumber--)
+	for (attNumber = maxAttributeNumber; attNumber > 0; attNumber--)
 	{
 		StrategyNumber strategy;
 
 		entry[1].sk_argument =
-			ObjectIdGetDatum(operatorClassObjectId[attributeNumber - 1]);
+			ObjectIdGetDatum(operatorClassObjectId[attNumber - 1]);
 
 		map = IndexStrategyGetStrategyMap(indexStrategy,
 										  maxStrategyNumber,
-										  attributeNumber);
+										  attNumber);
 
 		for (strategy = 1; strategy <= maxStrategyNumber; strategy++)
 			ScanKeyEntrySetIllegal(StrategyMapGetScanKeyEntry(map, strategy));
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 6d950e96942..600e9ddcaec 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.82 2000/11/10 00:33:08 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.83 2000/11/16 22:30:16 tgl Exp $
  *
  * NOTES
  *		Transaction aborts can now occur two ways:
@@ -1112,6 +1112,7 @@ CommitTransaction(void)
 	AtEOXact_nbtree();
 	AtCommit_Cache();
 	AtCommit_Locks();
+	AtEOXact_CatCache(true);
 	AtCommit_Memory();
 	AtEOXact_Files();
 
@@ -1192,6 +1193,7 @@ AbortTransaction(void)
 	AtEOXact_SPI();
 	AtEOXact_nbtree();
 	AtAbort_Cache();
+	AtEOXact_CatCache(false);
 	AtAbort_Memory();
 	AtEOXact_Files();