0001-Mark-a-cache-plan-as-dead-when-aborting-its-creating.patch

From 40b963d6496a42a71ef992f55963c1e77a7bb65b Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Thu, 21 Oct 2010 14:17:54 -0300
Subject: [PATCH] Mark a cache plan as dead when aborting its creating subtransaction.

Per a trouble report from Enova Financial's Jim Nasby and Jon Erdman.
---
 src/backend/commands/prepare.c        |    6 +++---
 src/backend/executor/spi.c            |    6 +++---
 src/backend/tcop/postgres.c           |    4 ++--
 src/backend/utils/cache/plancache.c   |   10 ++++++----
 src/backend/utils/mmgr/portalmem.c    |    2 +-
 src/backend/utils/resowner/resowner.c |    2 +-
 src/include/utils/plancache.h         |    2 +-
 src/pl/plpgsql/src/pl_exec.c          |    4 ++--
 8 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index c30ce35..8fb6b3c 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -250,7 +250,7 @@ ExecuteQuery(ExecuteStmt *stmt, const char *queryString,
 		MemoryContextSwitchTo(oldContext);
 
 		/* We no longer need the cached plan refcount ... */
-		ReleaseCachedPlan(cplan, true);
+		ReleaseCachedPlan(cplan, true, false);
 		/* ... and we don't want the portal to depend on it, either */
 		cplan = NULL;
 	}
@@ -568,7 +568,7 @@ FetchPreparedStatementTargetList(PreparedStatement *stmt)
 	/* Copy into caller's context so we can release the plancache entry */
 	tlist = (List *) copyObject(tlist);
 
-	ReleaseCachedPlan(cplan, true);
+	ReleaseCachedPlan(cplan, true, false);
 
 	return tlist;
 }
@@ -726,7 +726,7 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, ExplainStmt *stmt,
 	if (estate)
 		FreeExecutorState(estate);
 
-	ReleaseCachedPlan(cplan, true);
+	ReleaseCachedPlan(cplan, true, false);
 }
 
 /*
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 3cffc2a..d826236 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -1384,7 +1384,7 @@ SPI_is_cursor_plan(SPIPlanPtr plan)
 	{
 		/* Make sure the plan is up to date */
 		cplan = RevalidateCachedPlan(plansource, true);
-		ReleaseCachedPlan(cplan, true);
+		ReleaseCachedPlan(cplan, true, false);
 	}
 
 	_SPI_end_call(false);
@@ -1878,7 +1878,7 @@ _SPI_execute_plan(SPIPlanPtr plan, ParamListInfo paramLI,
 
 		/* Done with this plan, so release refcount */
 		if (cplan)
-			ReleaseCachedPlan(cplan, true);
+			ReleaseCachedPlan(cplan, true, false);
 		cplan = NULL;
 
 		/*
@@ -1894,7 +1894,7 @@ fail:
 
 	/* We no longer need the cached plan refcount, if any */
 	if (cplan)
-		ReleaseCachedPlan(cplan, true);
+		ReleaseCachedPlan(cplan, true, false);
 
 	/*
 	 * Pop the error context stack
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 43e912f..e7c798d 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1709,7 +1709,7 @@ exec_bind_message(StringInfo input_message)
 		MemoryContextSwitchTo(oldContext);
 
 		/* We no longer need the cached plan refcount ... */
-		ReleaseCachedPlan(cplan, true);
+		ReleaseCachedPlan(cplan, true, false);
 		/* ... and we don't want the portal to depend on it, either */
 		cplan = NULL;
 	}
@@ -2266,7 +2266,7 @@ exec_describe_statement_message(const char *stmt_name)
 
 		SendRowDescriptionMessage(psrc->resultDesc, tlist, NULL);
 
-		ReleaseCachedPlan(cplan, true);
+		ReleaseCachedPlan(cplan, true, false);
 	}
 	else
 		pq_putemptymessage('n');	/* NoData */
diff --git a/src/backend/utils/cache/plancache.c b/src/backend/utils/cache/plancache.c
index 6c3082d..338753e 100644
--- a/src/backend/utils/cache/plancache.c
+++ b/src/backend/utils/cache/plancache.c
@@ -367,7 +367,7 @@ DropCachedPlan(CachedPlanSource *plansource)
 
 	/* Decrement child CachePlan's refcount and drop if no longer needed */
 	if (plansource->plan)
-		ReleaseCachedPlan(plansource->plan, false);
+		ReleaseCachedPlan(plansource->plan, false, false);
 
 	/*
 	 * If CachedPlanSource has independent storage, just drop it.  Otherwise
@@ -381,7 +381,7 @@ DropCachedPlan(CachedPlanSource *plansource)
 	else
 	{
 		Assert(plansource->context == plansource->orig_plan->context);
-		ReleaseCachedPlan(plansource->orig_plan, false);
+		ReleaseCachedPlan(plansource->orig_plan, false, false);
 	}
 }
 
@@ -455,7 +455,7 @@ RevalidateCachedPlan(CachedPlanSource *plansource, bool useResOwner)
 	if (plan && plan->dead)
 	{
 		plansource->plan = NULL;
-		ReleaseCachedPlan(plan, false);
+		ReleaseCachedPlan(plan, false, false);
 		plan = NULL;
 	}
 
@@ -588,12 +588,14 @@ RevalidateCachedPlan(CachedPlanSource *plansource, bool useResOwner)
  * Portal.	Transient references should be protected by a resource owner.
  */
 void
-ReleaseCachedPlan(CachedPlan *plan, bool useResOwner)
+ReleaseCachedPlan(CachedPlan *plan, bool useResOwner, bool isabort)
 {
 	if (useResOwner)
 		ResourceOwnerForgetPlanCacheRef(CurrentResourceOwner, plan);
 	Assert(plan->refcount > 0);
 	plan->refcount--;
+	if (isabort)
+		plan->dead = true;
 	if (plan->refcount == 0)
 		MemoryContextDelete(plan->context);
 }
diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index 0445705..e01b3b0 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -326,7 +326,7 @@ PortalReleaseCachedPlan(Portal portal)
 {
 	if (portal->cplan)
 	{
-		ReleaseCachedPlan(portal->cplan, false);
+		ReleaseCachedPlan(portal->cplan, false, false);
 		portal->cplan = NULL;
 
 		/*
diff --git a/src/backend/utils/resowner/resowner.c b/src/backend/utils/resowner/resowner.c
index 9332678..c0cd77b 100644
--- a/src/backend/utils/resowner/resowner.c
+++ b/src/backend/utils/resowner/resowner.c
@@ -305,7 +305,7 @@ ResourceOwnerReleaseInternal(ResourceOwner owner,
 		{
 			if (isCommit)
 				PrintPlanCacheLeakWarning(owner->planrefs[owner->nplanrefs - 1]);
-			ReleaseCachedPlan(owner->planrefs[owner->nplanrefs - 1], true);
+			ReleaseCachedPlan(owner->planrefs[owner->nplanrefs - 1], true, !isCommit);
 		}
 		/* Ditto for tupdesc references */
 		while (owner->ntupdescs > 0)
diff --git a/src/include/utils/plancache.h b/src/include/utils/plancache.h
index ea919bd..1be054d 100644
--- a/src/include/utils/plancache.h
+++ b/src/include/utils/plancache.h
@@ -108,7 +108,7 @@ extern CachedPlanSource *FastCreateCachedPlan(Node *raw_parse_tree,
 extern void DropCachedPlan(CachedPlanSource *plansource);
 extern CachedPlan *RevalidateCachedPlan(CachedPlanSource *plansource,
 					 bool useResOwner);
-extern void ReleaseCachedPlan(CachedPlan *plan, bool useResOwner);
+extern void ReleaseCachedPlan(CachedPlan *plan, bool useResOwner, bool isabort);
 extern bool CachedPlanIsValid(CachedPlanSource *plansource);
 extern TupleDesc PlanCacheComputeResultDesc(List *stmt_list);
 
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 8d0c625..6d5d729 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -4435,7 +4435,7 @@ exec_eval_simple_expr(PLpgSQL_execstate *estate,
 		if (expr->expr_simple_expr == NULL)
 		{
 			/* Ooops, release refcount and fail */
-			ReleaseCachedPlan(cplan, true);
+			ReleaseCachedPlan(cplan, true, false);
 			return false;
 		}
 	}
@@ -4525,7 +4525,7 @@ exec_eval_simple_expr(PLpgSQL_execstate *estate,
 	/*
 	 * Now we can release our refcount on the cached plan.
 	 */
-	ReleaseCachedPlan(cplan, true);
+	ReleaseCachedPlan(cplan, true, false);
 
 	/*
 	 * That's it.
-- 
1.7.1