Merge branch '2.0' into merge/2.0-into-2.1/memory-leak-in-rc_conn_mgr_stats

Fix memory leak in riak_core_connection_mgr_stats: RIAK-2231

Author: jvoegele

src/riak_core_connection_mgr.erl

@@ -584,14 +584,17 @@ locate_endpoints({Type, Name}, Strategy, Locators) ->
 %% our book keeping for that endpoint. Black-list it, and
 %% adjust a backoff timer so that we wait a while before
 %% trying this endpoint again.
+
+-spec fail_endpoint(ip_addr(), term(), proto_id(), #state{}) -> #state{}.
 fail_endpoint(Addr, Reason, ProtocolId, State) ->
     %% update the stats module
-    Stat = {conn_error, Reason},
+    Err = reason_to_atom(Reason),
+    Stat = {conn_error, Err},
     riak_core_connection_mgr_stats:update(Stat, Addr, ProtocolId),
     %% update the endpoint
     Fun = fun(EP=#ep{backoff_delay = Backoff, failures = Failures}) ->
                   erlang:send_after(Backoff, self(), {backoff_timer, Addr}),
-                  EP#ep{failures = orddict:update_counter(Reason, 1, Failures),
+                  EP#ep{failures = orddict:update_counter(Err, 1, Failures),
                         nb_failures = EP#ep.nb_failures + 1,
                         backoff_delay = increase_backoff(Backoff),
                         last_fail_time = os:timestamp(),
@@ -600,6 +603,18 @@ fail_endpoint(Addr, Reason, ProtocolId, State) ->
           end,
     update_endpoint(Addr, Fun, State).
 
+%% Attempt to extract atom from an error reason.
+
+-spec reason_to_atom(term()) -> atom().
+reason_to_atom({{Err, _Val}, _Stack}) when is_atom(Err) ->
+    Err;
+reason_to_atom({Err, _Stack}) when is_atom(Err) ->
+    Err;
+reason_to_atom(Reason) when is_atom(Reason) ->
+    Reason;
+reason_to_atom(_Reason) ->
+    unknown_reason.
+
 connect_endpoint(Addr, State) ->
     update_endpoint(Addr, fun(EP) ->
                                   EP#ep{is_black_listed = false,