From: Sage Weil <sage@redhat.com>
Date: Thu, 13 Sep 2018 19:00:44 +0000 (-0500)
Subject: mon: fix ref cycle breakage in handle_forward
X-Git-Tag: v14.0.1~26^2~17
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=9ddb9bfd8b541b2c154064277b725b0289aafb93;p=ceph.git

mon: fix ref cycle breakage in handle_forward

We now rely on the session -> connection ref for printing
remote addr, peer_global_id, and so on.  Change this code to
break the ref cycle instead by removing the con->session link,
which is only needed by the MonOpRequest ctor called at the top
of _ms_dispatch.

Signed-off-by: Sage Weil <sage@redhat.com>
---

diff --git a/src/mon/Monitor.cc b/src/mon/Monitor.cc
index b6fe93de226fd..76ee7b1911a40 100644
--- a/src/mon/Monitor.cc
+++ b/src/mon/Monitor.cc
@@ -3740,18 +3740,13 @@ void Monitor::handle_forward(MonOpRequestRef op)
      */
     req->rx_election_epoch = get_epoch();
 
-    /* Because this is a special fake connection, we need to break
-       the ref loop between Connection and MonSession differently
-       than we normally do. Here, the Message refers to the Connection
-       which refers to the Session, and nobody else refers to the Connection
-       or the Session. And due to the special nature of this message,
-       nobody refers to the Connection via the Session. So, clear out that
-       half of the ref loop.*/
-    s->con.reset(NULL);
-
     dout(10) << " mesg " << req << " from " << m->get_source_addr() << dendl;
-
     _ms_dispatch(req);
+
+    // break the session <-> con ref loop by removing the con->session
+    // reference, which is no longer needed once the MonOpRequest is
+    // set up.
+    c->set_priv(NULL);
   }
 }