glusterd : Fix glusterd mem leaks

Problem:   glusterd eats a huge amount of meory during volume set/stop/start.

Solution:  At the time of compare graph topology create a graph and populate
           key values in the dictionary, after finished graph comparison we
           do destroy the new graph.At the time of construct graph we don't take
           any reference and for server xlators we do take reference in
           server_setvolume so in glusterd we do take reference after prepare
           a new graph while we do create a graph to compare graph topology.

BUG: 1520245
Change-Id: I573133d57771b7dc431a04422c5001a06b7dda9a
Signed-off-by: Mohit Agrawal <moagrawa@redhat.com>

2 files changed, 37 insertions, 0 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-handshake.c b/xlators/mgmt/glusterd/src/glusterd-handshake.c
index 56ddce88d5e..d0756fded40 100644
--- a/xlators/mgmt/glusterd/src/glusterd-handshake.c
+++ b/xlators/mgmt/glusterd/src/glusterd-handshake.c
@@ -1293,6 +1293,9 @@ out:
         if (rsp.hndsk.hndsk_val)
                 GF_FREE (rsp.hndsk.hndsk_val);
 
+        if (args_dict)
+                dict_unref (args_dict);
+
         return ret;
 }
 
diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index aa8b4e4ede8..24d276b7cb0 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -8992,6 +8992,36 @@ glusterd_defrag_volume_status_update (glusterd_volinfo_t *volinfo,
 
         return ret;
 }
+/*
+   The function is required to take dict ref for every xlator at graph.
+   At the time of compare graph topology create a graph and populate
+   key values in the dictionary, after finished graph comparison we do destroy
+   the new graph.At the time of construct graph we don't take any reference
+   so to avoid leak due to ref counter underflow we need to call dict_ref here.
+
+*/
+
+void
+glusterd_graph_take_reference (xlator_t *tree)
+{        xlator_t *trav = tree;
+         xlator_t *prev = tree;
+
+        if (!tree) {
+                gf_msg ("parser", GF_LOG_ERROR, 0, LG_MSG_TREE_NOT_FOUND,
+                        "Translator tree not found");
+                return;
+        }
+
+        while (prev) {
+                trav = prev->next;
+                if (prev->options)
+                        dict_ref (prev->options);
+                prev = trav;
+        }
+        return;
+}
+
+
 
 int
 glusterd_check_topology_identical (const char   *filename1,
@@ -9039,11 +9069,15 @@ glusterd_check_topology_identical (const char   *filename1,
         if (grph1 == NULL)
                 goto out;
 
+        glusterd_graph_take_reference (grph1->first);
+
         /* create the graph for filename2 */
         grph2 = glusterfs_graph_construct(fp2);
         if (grph2 == NULL)
                 goto out;
 
+        glusterd_graph_take_reference (grph2->first);
+
         /* compare the graph topology */
         *identical = is_graph_topology_equal(grph1, grph2);
         ret = 0; /* SUCCESS */