4 files changed, 58 insertions, 9 deletions

diff --git a/src/backend/utils/activity/wait_event_names.txt b/src/backend/utils/activity/wait_event_names.txt
index 4da68312b5f..0be307d2ca0 100644
--- a/src/backend/utils/activity/wait_event_names.txt
+++ b/src/backend/utils/activity/wait_event_names.txt
@@ -356,9 +356,13 @@ AioWorkerSubmissionQueue	"Waiting to access AIO worker submission queue."
 #
 # END OF PREDEFINED LWLOCKS (DO NOT CHANGE THIS LINE)
 #
-# Predefined LWLocks (i.e., those declared in lwlocknames.h) must be listed
-# in the section above and must be listed in the same order as in
-# lwlocknames.h.  Other LWLocks must be listed in the section below.
+# Predefined LWLocks (i.e., those declared at the top of lwlocknames.h) must be
+# listed in the section above and must be listed in the same order as in
+# lwlocknames.h.
+#
+# Likewise, the built-in LWLock tranches (i.e., those declared at the bottom of
+# lwlocknames.h) must be listed in the section below and must be listed in the
+# same order as in lwlocknames.h.
 #
 
 XactBuffer	"Waiting for I/O on a transaction status SLRU buffer."
diff --git a/src/backend/utils/cache/plancache.c b/src/backend/utils/cache/plancache.c
index 89a1c79e984..f4d2b9458a5 100644
--- a/src/backend/utils/cache/plancache.c
+++ b/src/backend/utils/cache/plancache.c
@@ -1283,6 +1283,7 @@ GetCachedPlan(CachedPlanSource *plansource, ParamListInfo boundParams,
 	CachedPlan *plan = NULL;
 	List	   *qlist;
 	bool		customplan;
+	ListCell   *lc;
 
 	/* Assert caller is doing things in a sane order */
 	Assert(plansource->magic == CACHEDPLANSOURCE_MAGIC);
@@ -1385,6 +1386,13 @@ GetCachedPlan(CachedPlanSource *plansource, ParamListInfo boundParams,
 		plan->is_saved = true;
 	}
 
+	foreach(lc, plan->stmt_list)
+	{
+		PlannedStmt *pstmt = (PlannedStmt *) lfirst(lc);
+
+		pstmt->cached_plan_type = customplan ? PLAN_CACHE_CUSTOM : PLAN_CACHE_GENERIC;
+	}
+
 	return plan;
 }
 
diff --git a/src/backend/utils/hash/dynahash.c b/src/backend/utils/hash/dynahash.c
index 1ad155d446e..42e9be274fc 100644
--- a/src/backend/utils/hash/dynahash.c
+++ b/src/backend/utils/hash/dynahash.c
@@ -195,6 +195,7 @@ struct HASHHDR
 	long		ssize;			/* segment size --- must be power of 2 */
 	int			sshift;			/* segment shift = log2(ssize) */
 	int			nelem_alloc;	/* number of entries to allocate at once */
+	bool		isfixed;		/* if true, don't enlarge */
 
 #ifdef HASH_STATISTICS
 
@@ -227,7 +228,6 @@ struct HTAB
 	MemoryContext hcxt;			/* memory context if default allocator used */
 	char	   *tabname;		/* table name (for error messages) */
 	bool		isshared;		/* true if table is in shared memory */
-	bool		isfixed;		/* if true, don't enlarge */
 
 	/* freezing a shared table isn't allowed, so we can keep state here */
 	bool		frozen;			/* true = no more inserts allowed */
@@ -618,8 +618,10 @@ hash_create(const char *tabname, long nelem, const HASHCTL *info, int flags)
 		}
 	}
 
+	/* Set isfixed if requested, but not till after we build initial entries */
 	if (flags & HASH_FIXED_SIZE)
-		hashp->isfixed = true;
+		hctl->isfixed = true;
+
 	return hashp;
 }
 
@@ -644,6 +646,8 @@ hdefault(HTAB *hashp)
 	hctl->ssize = DEF_SEGSIZE;
 	hctl->sshift = DEF_SEGSIZE_SHIFT;
 
+	hctl->isfixed = false;		/* can be enlarged */
+
 #ifdef HASH_STATISTICS
 	hctl->accesses = hctl->collisions = 0;
 #endif
@@ -1713,7 +1717,7 @@ element_alloc(HTAB *hashp, int nelem, int freelist_idx)
 	HASHELEMENT *prevElement;
 	int			i;
 
-	if (hashp->isfixed)
+	if (hctl->isfixed)
 		return false;
 
 	/* Each element has a HASHELEMENT header plus user data. */
diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c
index 15fa4d0a55e..ce01dce9861 100644
--- a/src/backend/utils/mmgr/mcxt.c
+++ b/src/backend/utils/mmgr/mcxt.c
@@ -560,9 +560,7 @@ MemoryContextDeleteChildren(MemoryContext context)
  * the specified context, since that means it will automatically be freed
  * when no longer needed.
  *
- * There is no API for deregistering a callback once registered.  If you
- * want it to not do anything anymore, adjust the state pointed to by its
- * "arg" to indicate that.
+ * Note that callers can assume this cannot fail.
  */
 void
 MemoryContextRegisterResetCallback(MemoryContext context,
@@ -578,6 +576,41 @@ MemoryContextRegisterResetCallback(MemoryContext context,
 }
 
 /*
+ * MemoryContextUnregisterResetCallback
+ *		Undo the effects of MemoryContextRegisterResetCallback.
+ *
+ * This can be used if a callback's effects are no longer required
+ * at some point before the context has been reset/deleted.  It is the
+ * caller's responsibility to pfree the callback struct (if needed).
+ *
+ * An assertion failure occurs if the callback was not registered.
+ * We could alternatively define that case as a no-op, but that seems too
+ * likely to mask programming errors such as passing the wrong context.
+ */
+void
+MemoryContextUnregisterResetCallback(MemoryContext context,
+									 MemoryContextCallback *cb)
+{
+	MemoryContextCallback *prev,
+			   *cur;
+
+	Assert(MemoryContextIsValid(context));
+
+	for (prev = NULL, cur = context->reset_cbs; cur != NULL;
+		 prev = cur, cur = cur->next)
+	{
+		if (cur != cb)
+			continue;
+		if (prev)
+			prev->next = cur->next;
+		else
+			context->reset_cbs = cur->next;
+		return;
+	}
+	Assert(false);
+}
+
+/*
  * MemoryContextCallResetCallbacks
  *		Internal function to call all registered callbacks for context.
  */