2 files changed, 47 insertions, 20 deletions

diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 4f4ce757623..9bda1aa6bc6 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -5279,20 +5279,7 @@ AbortSubTransaction(void)
 
 		AtEOSubXact_RelationCache(false, s->subTransactionId,
 								  s->parent->subTransactionId);
-
-
-		/*
-		 * AtEOSubXact_Inval sometimes needs to temporarily bump the refcount
-		 * on the relcache entries that it processes.  We cannot use the
-		 * subtransaction's resource owner anymore, because we've already
-		 * started releasing it.  But we can use the parent resource owner.
-		 */
-		CurrentResourceOwner = s->parent->curTransactionOwner;
-
 		AtEOSubXact_Inval(false);
-
-		CurrentResourceOwner = s->curTransactionOwner;
-
 		ResourceOwnerRelease(s->curTransactionOwner,
 							 RESOURCE_RELEASE_LOCKS,
 							 false, false);
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index cc9b0c6524f..35dbb87ae3d 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -275,6 +275,7 @@ static HTAB *OpClassCache = NULL;
 
 static void RelationCloseCleanup(Relation relation);
 static void RelationDestroyRelation(Relation relation, bool remember_tupdesc);
+static void RelationInvalidateRelation(Relation relation);
 static void RelationClearRelation(Relation relation, bool rebuild);
 
 static void RelationReloadIndexInfo(Relation relation);
@@ -2513,6 +2514,31 @@ RelationDestroyRelation(Relation relation, bool remember_tupdesc)
 }
 
 /*
+ * RelationInvalidateRelation - mark a relation cache entry as invalid
+ *
+ * An entry that's marked as invalid will be reloaded on next access.
+ */
+static void
+RelationInvalidateRelation(Relation relation)
+{
+	/*
+	 * Make sure smgr and lower levels close the relation's files, if they
+	 * weren't closed already.  If the relation is not getting deleted, the
+	 * next smgr access should reopen the files automatically.  This ensures
+	 * that the low-level file access state is updated after, say, a vacuum
+	 * truncation.
+	 */
+	RelationCloseSmgr(relation);
+
+	/* Free AM cached data, if any */
+	if (relation->rd_amcache)
+		pfree(relation->rd_amcache);
+	relation->rd_amcache = NULL;
+
+	relation->rd_isvalid = false;
+}
+
+/*
  * RelationClearRelation
  *
  *	 Physically blow away a relation cache entry, or reset it and rebuild
@@ -2846,14 +2872,28 @@ RelationFlushRelation(Relation relation)
 		 * New relcache entries are always rebuilt, not flushed; else we'd
 		 * forget the "new" status of the relation.  Ditto for the
 		 * new-relfilenumber status.
-		 *
-		 * The rel could have zero refcnt here, so temporarily increment the
-		 * refcnt to ensure it's safe to rebuild it.  We can assume that the
-		 * current transaction has some lock on the rel already.
 		 */
-		RelationIncrementReferenceCount(relation);
-		RelationClearRelation(relation, true);
-		RelationDecrementReferenceCount(relation);
+		if (IsTransactionState() && relation->rd_droppedSubid == InvalidSubTransactionId)
+		{
+			/*
+			 * The rel could have zero refcnt here, so temporarily increment
+			 * the refcnt to ensure it's safe to rebuild it.  We can assume
+			 * that the current transaction has some lock on the rel already.
+			 */
+			RelationIncrementReferenceCount(relation);
+			RelationClearRelation(relation, true);
+			RelationDecrementReferenceCount(relation);
+		}
+		else
+		{
+			/*
+			 * During abort processing, the current resource owner is not
+			 * valid and we cannot hold a refcnt.  Without a valid
+			 * transaction, RelationClearRelation() would just mark the rel as
+			 * invalid anyway, so we can do the same directly.
+			 */
+			RelationInvalidateRelation(relation);
+		}
 	}
 	else
 	{