From 965d737d2bfb42733f6149b2b9f5496552ece858 Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@newdream.net>
Date: Wed, 17 Mar 2010 21:47:00 -0700
Subject: [PATCH] mds: drop gather if it's empty

This can happen from scatter_nudge, which may add a sub and then
complete it, emptying out the C_Gather.
---
 src/mds/journal.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/mds/journal.cc b/src/mds/journal.cc
index 28ef2a98e1007..44ce5b0579c7a 100644
--- a/src/mds/journal.cc
+++ b/src/mds/journal.cc
@@ -296,6 +296,11 @@ C_Gather *LogSegment::try_to_expire(MDS *mds)
     }
   }
 
+  if (gather && gather->empty()) {
+    delete gather;
+    gather = NULL;
+  }
+
   if (gather) {
     dout(6) << "LogSegment(" << offset << ").try_to_expire waiting" << dendl;
     mds->mdlog->flush();