glusterd : introduce timer in mgmt_v3_lock

Problem:
In a multinode environment, if two of the op-sm transactions
are initiated on one of the receiver nodes at the same time,
there might be a possibility that glusterd  may end up in
stale lock.

Solution:
During mgmt_v3_lock a registration is made to  gf_timer_call_after
which release the lock after certain period of time

>mainline patch : https://review.gluster.org/#/c/18437/

Change-Id: I16cc2e5186a2e8a5e35eca2468b031811e093843
BUG: 1503239
Signed-off-by: Gaurav Yadav <gyadav@redhat.com>

1 files changed, 20 insertions, 3 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd.c b/xlators/mgmt/glusterd/src/glusterd.c
index 81a3206d3f8..25089aef63b 100644
--- a/xlators/mgmt/glusterd/src/glusterd.c
+++ b/xlators/mgmt/glusterd/src/glusterd.c
@@ -1824,12 +1824,19 @@ init (xlator_t *this)
         if (ret)
                 goto out;
 
-         conf->base_port = GF_IANA_PRIV_PORTS_START;
-         if (dict_get_uint32(this->options, "base-port", &conf->base_port) == 0) {
+        conf->base_port = GF_IANA_PRIV_PORTS_START;
+        if (dict_get_uint32(this->options, "base-port", &conf->base_port) == 0) {
                 gf_msg (this->name, GF_LOG_INFO, 0,
                         GD_MSG_DICT_SET_FAILED,
                         "base-port override: %d", conf->base_port);
-         }
+        }
+        conf->mgmt_v3_lock_timeout = GF_LOCK_TIMER;
+        if (dict_get_uint32 (this->options, "lock-timer",
+                             &conf->mgmt_v3_lock_timeout) == 0) {
+                gf_msg (this->name, GF_LOG_INFO, 0,
+                        GD_MSG_DICT_SET_FAILED,
+                        "lock-timer override: %d", conf->mgmt_v3_lock_timeout);
+        }
 
         /* Set option to run bricks on valgrind if enabled in glusterd.vol */
         this->ctx->cmd_args.valgrind = valgrind;
@@ -1855,6 +1862,7 @@ init (xlator_t *this)
 
         this->private = conf;
         glusterd_mgmt_v3_lock_init ();
+        glusterd_mgmt_v3_lock_timer_init();
         glusterd_txn_opinfo_dict_init ();
 
         glusterd_shdsvc_build (&conf->shd_svc);
@@ -2017,6 +2025,7 @@ fini (xlator_t *this)
                 gf_store_handle_destroy (conf->handle);
         glusterd_sm_tr_log_delete (&conf->op_sm_log);
         glusterd_mgmt_v3_lock_fini ();
+        glusterd_mgmt_v3_lock_timer_fini ();
         glusterd_txn_opinfo_dict_fini ();
         GF_FREE (conf);
 
@@ -2135,6 +2144,14 @@ struct volume_options options[] = {
           .type = GF_OPTION_TYPE_INT,
           .description = "Sets the base port for portmap query"
         },
+        { .key = {"mgmt-v3-lock-timeout"},
+          .type = GF_OPTION_TYPE_INT,
+          .max = 600,
+          .description = "Sets the mgmt-v3-lock-timeout for transactions."
+                         "Specifes the default timeout value after which "
+                         "lock acquired while performing transaction will "
+                         "be released."
+        },
         { .key = {"snap-brick-path"},
           .type = GF_OPTION_TYPE_STR,
           .description = "directory where the bricks for the snapshots will be created"