Fix plancache's invalidation callback to do the right thing for a SI

reset event, namely invalidate everything.  This oversight probably
explains the rare failures that some buildfarm machines have been
showing for the plancache regression test.

src/backend/utils/cache/plancache.c

@@ -33,7 +33,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/plancache.c,v 1.4 2007/03/23 19:53:51 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/plancache.c,v 1.5 2007/03/26 00:36:19 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -812,6 +812,9 @@ PlanCacheComputeResultDesc(List *stmt_list)
 /*
  * PlanCacheCallback
  *		Relcache inval callback function
+ *
+ * Invalidate all plans mentioning the given rel, or all plans mentioning
+ * any rel at all if relid == InvalidOid.
  */
 static void
 PlanCacheCallback(Datum arg, Oid relid)
@@ -843,7 +846,7 @@ PlanCacheCallback(Datum arg, Oid relid)
 
 					if (rte->rtekind != RTE_RELATION)
 						continue;
-					if (relid == rte->relid)
+					if (relid == rte->relid || relid == InvalidOid)
 					{
 						/* Invalidate the plan! */
 						plan->dead = true;
@@ -883,10 +886,11 @@ PlanCacheCallback(Datum arg, Oid relid)
 static void
 InvalRelid(Oid relid, LOCKMODE lockmode, InvalRelidContext *context)
 {
-	if (relid == context->inval_relid)
+	if (relid == context->inval_relid || context->inval_relid == InvalidOid)
 		context->plan->dead = true;
 }
 
+
 /*
  * HaveCachedPlans 
  *		Check if the plancache has stored any plans at all.
@@ -896,4 +900,3 @@ HaveCachedPlans(void)
 {
 	return (cached_plans_list != NIL);
 }
-