mds: don't send null ack in do_snap_update

(In this case, it's a null flushsnap.)

diff --git a/src/mds/Locker.cc b/src/mds/Locker.cc
index 7ab98c219158ebc7bcf94b9be5da7b1468cd127c..801f197a63648704ba0428c4338c018659303751 100644 (file)
--- a/src/mds/Locker.cc
+++ b/src/mds/Locker.cc
@@ -2034,7 +2034,8 @@ void Locker::_do_snap_update(CInode *in, int dirty, snapid_t follows, MClientCap
     // hmm, i guess snap was already deleted?  just ack!
     dout(10) << " wow, the snap following " << follows
             << " was already deleted.  nothing to record, just ack." << dendl;
-    mds->send_message_client_counted(ack, m->get_connection());
+    if (ack)
+      mds->send_message_client_counted(ack, m->get_connection());
     return;
   }