rpc/socket.c: Modify approach to cleanup threads of socket_poller in socket_spawn.

    Problem: Current approach to cleanup threads of socket_poller is not appropriate.

    Solution: Enable detach flag at the time of thread creation in socket_spawn.

    Fix: Write a new wrapper(gf_create_detach_thread) to create detachable thread
         instead of store thread ids in a queue.

    Test: Fix is verfied on gluster process, To test the patch followed below procedure
          Enable the client.ssl and server.ssl option on the volume
          Start the volume and count anon segment in pmap output for glusterd process
          pmap -x <glusterd-pid> | grep "\[ anon \]" | wc -l
          Stop the volume and check again count of anon segment it should not increase.

Signed-off-by: Mohit Agrawal <moagrawa@redhat.com>
Change-Id: Ib8f7ec7504ec8f6f74b45ce6719b6fb47f9fdc37
BUG: 1336508
Reviewed-on: http://review.gluster.org/14694
Smoke: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Atin Mukherjee <amukherj@redhat.com>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>

4 files changed, 87 insertions, 142 deletions

diff --git a/libglusterfs/src/common-utils.c b/libglusterfs/src/common-utils.c
index a225c957f2e..97d9ef8da1a 100644
--- a/libglusterfs/src/common-utils.c
+++ b/libglusterfs/src/common-utils.c
@@ -3555,6 +3555,36 @@ gf_thread_create (pthread_t *thread, const pthread_attr_t *attr,
 }
 
 int
+gf_thread_create_detached (pthread_t *thread,
+                         void *(*start_routine)(void *), void *arg)
+{
+        pthread_attr_t attr;
+        int ret = -1;
+
+        ret = pthread_attr_init (&attr);
+        if (ret) {
+                gf_msg (THIS->name, GF_LOG_ERROR, ret,
+                        LG_MSG_PTHREAD_ATTR_INIT_FAILED,
+                        "Thread attribute initialization failed");
+                return -1;
+        }
+
+        pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
+
+        ret = gf_thread_create (thread, &attr, start_routine, arg);
+        if (ret) {
+                gf_msg (THIS->name, GF_LOG_ERROR, ret,
+                        LG_MSG_PTHREAD_FAILED,
+                        "Thread creation failed");
+                ret = -1;
+        }
+
+        pthread_attr_destroy (&attr);
+
+        return ret;
+}
+
+int
 gf_skip_header_section (int fd, int header_len)
 {
         int  ret           = -1;
diff --git a/libglusterfs/src/common-utils.h b/libglusterfs/src/common-utils.h
index 09d585ad9c3..4741d430a03 100644
--- a/libglusterfs/src/common-utils.h
+++ b/libglusterfs/src/common-utils.h
@@ -766,6 +766,9 @@ int gf_set_timestamp  (const char *src, const char* dest);
 
 int gf_thread_create (pthread_t *thread, const pthread_attr_t *attr,
                       void *(*start_routine)(void *), void *arg);
+int gf_thread_create_detached (pthread_t *thread,
+                      void *(*start_routine)(void *), void *arg);
+
 gf_boolean_t
 gf_is_service_running (char *pidfile, int *pid);
 int
diff --git a/libglusterfs/src/libglusterfs-messages.h b/libglusterfs/src/libglusterfs-messages.h
index c0bcabac798..d18f4cb3112 100644
--- a/libglusterfs/src/libglusterfs-messages.h
+++ b/libglusterfs/src/libglusterfs-messages.h
@@ -36,7 +36,7 @@
  */
 
 #define GLFS_LG_BASE            GLFS_MSGID_COMP_LIBGLUSTERFS
-#define GLFS_LG_NUM_MESSAGES    205
+#define GLFS_LG_NUM_MESSAGES    206
 #define GLFS_LG_MSGID_END       (GLFS_LG_BASE + GLFS_LG_NUM_MESSAGES + 1)
 /* Messaged with message IDs */
 #define glfs_msg_start_lg GLFS_LG_BASE, "Invalid: Start of messages"
@@ -1754,6 +1754,14 @@
  * @recommendedaction
  *
  */
+#define LG_MSG_PTHREAD_ATTR_INIT_FAILED                  (GLFS_LG_BASE + 206)
+
+/*!
+ * @messageid
+ * @diagnosis
+ * @recommendedaction
+ *
+ */
 /*------------*/
 
 #define glfs_msg_end_lg GLFS_LG_MSGID_END, "Invalid: End of messages"
diff --git a/rpc/rpc-transport/socket/src/socket.c b/rpc/rpc-transport/socket/src/socket.c
index 209d89a225b..030a37961b6 100644
--- a/rpc/rpc-transport/socket/src/socket.c
+++ b/rpc/rpc-transport/socket/src/socket.c
@@ -187,117 +187,6 @@ struct socket_connect_error_state_ {
 };
 typedef struct socket_connect_error_state_ socket_connect_error_state_t;
 
-
-/* This timer and queue are used to reap dead threads. The timer triggers every
- * minute and pthread_joins any threads that added themselves to the reap queue
- *
- * TODO: Make the timer configurable? (Not sure if required)
- */
-static gf_timer_t *reap_timer;
-static struct list_head reap_queue;
-static pthread_mutex_t reap_lock = PTHREAD_MUTEX_INITIALIZER;
-const struct timespec reap_ts = {60, 0};
-
-struct tid_wrap {
-        struct list_head list;
-        pthread_t tid;
-};
-
-/* _socket_reap_own_threads iterated over the queue of tid's and pthread_joins
- * them.  If a thread join fails, it logs the failure and continues
- */
-static void
-_socket_reap_own_threads() {
-        struct tid_wrap *node = NULL;
-        struct tid_wrap *tmp = NULL;
-        pthread_t tid = 0;
-        int i = 0;
-
-        list_for_each_entry_safe (node, tmp, &reap_queue, list) {
-                list_del_init (&node->list);
-                if (pthread_join (node->tid, NULL)) {
-                        gf_log (THIS->name, GF_LOG_ERROR,
-                                "own-thread: failed to join thread (tid: %zu)",
-                                tid);
-                }
-                node->tid = 0;
-                GF_FREE (node);
-                node = NULL;
-                i++;
-        }
-
-        if (i) {
-                gf_log (THIS->name, GF_LOG_TRACE, "reaped %d own-threads", i);
-        }
-
-        return;
-}
-
-/* socket_thread_reaper reaps threads and restarts the reap_timer
- */
-static void
-socket_thread_reaper () {
-
-        pthread_mutex_lock (&reap_lock);
-
-        gf_timer_call_cancel (THIS->ctx, reap_timer);
-        reap_timer = 0;
-
-        _socket_reap_own_threads();
-
-        reap_timer = gf_timer_call_after (THIS->ctx, reap_ts,
-                                          socket_thread_reaper, NULL);
-        if (!reap_timer)
-                gf_log (THIS->name, GF_LOG_ERROR,
-                        "failed to restart socket own-thread reap timer");
-
-        pthread_mutex_unlock (&reap_lock);
-
-        return;
-}
-
-/* socket_thread_reaper_init initializes reap_timer and reap_queue.
- * Initializations are done only the first time this is called.
- *
- * To make sure that the reap_timer is always run, reaper_init it is better to
- * call this whenever an own-thread is launched
- */
-static void
-socket_thread_reaper_init () {
-        pthread_mutex_lock (&reap_lock);
-
-        if (reap_timer == NULL) {
-                reap_timer = gf_timer_call_after (THIS->ctx, reap_ts,
-                                                  socket_thread_reaper, NULL);
-                INIT_LIST_HEAD (&reap_queue);
-        }
-
-        pthread_mutex_unlock (&reap_lock);
-
-        return;
-}
-
-/* socket_thread_reaper_add adds the given thread id to the queue of threads
- * that will be reaped by socket_thread_reaper
- * own-threads need to call this with their thread-ids before dying
- */
-static int
-socket_thread_reaper_add (pthread_t tid) {
-        struct tid_wrap *node = NULL;
-
-        pthread_mutex_lock (&reap_lock);
-
-        node = GF_CALLOC (1, sizeof (*node), gf_sock_mt_tid_wrap);
-        node->tid = tid;
-        INIT_LIST_HEAD (&node->list);
-        list_add_tail (&node->list, &reap_queue);
-
-        pthread_mutex_unlock (&reap_lock);
-
-        return 0;
-}
-
-
 static int socket_init (rpc_transport_t *this);
 
 static void
@@ -2640,10 +2529,6 @@ err:
         pthread_mutex_unlock(&priv->lock);
         rpc_transport_notify (this, RPC_TRANSPORT_DISCONNECT, this);
 
-        /* Add the thread to the reap_queue before freeing up the transport and
-         * dying
-         */
-        socket_thread_reaper_add (priv->thread);
 
         rpc_transport_unref (this);
 
@@ -2651,11 +2536,11 @@ err:
 }
 
 
-static void
+static int
 socket_spawn (rpc_transport_t *this)
 {
         socket_private_t        *priv   = this->private;
-
+        int ret = -1;
         switch (priv->ot_state) {
         case OT_IDLE:
         case OT_PLEASE_DIE:
@@ -2663,7 +2548,7 @@ socket_spawn (rpc_transport_t *this)
         default:
                 gf_log (this->name, GF_LOG_WARNING,
                         "refusing to start redundant poller");
-                return;
+                return ret;
         }
 
         priv->ot_gen += 7;
@@ -2671,12 +2556,16 @@ socket_spawn (rpc_transport_t *this)
         gf_log (this->name, GF_LOG_TRACE,
                 "spawning %p with gen %u", this, priv->ot_gen);
 
-        if (gf_thread_create(&priv->thread,NULL,socket_poller,this) != 0) {
+        /* Create thread after enable detach flag */
+
+        ret = gf_thread_create_detached (&priv->thread, socket_poller, this);
+        if (ret) {
                 gf_log (this->name, GF_LOG_ERROR,
                         "could not create poll thread");
+                ret = -1;
         }
-        /* start the reaper thread */
-        socket_thread_reaper_init();
+
+        return ret;
 }
 
 static int
@@ -2860,30 +2749,38 @@ socket_server_event_handler (int fd, int idx, void *data,
                                 new_priv->is_server = _gf_true;
                                 rpc_transport_ref (new_trans);
 
-				if (new_priv->own_thread) {
-					if (pipe(new_priv->pipe) < 0) {
-						gf_log(this->name,GF_LOG_ERROR,
-						       "could not create pipe");
-					}
-                                        socket_spawn(new_trans);
-				}
-				else {
-					new_priv->idx =
-						event_register (ctx->event_pool,
-								new_sock,
-								socket_event_handler,
-								new_trans,
-								1, 0);
-					if (new_priv->idx == -1)
-						ret = -1;
-				}
+                                if (new_priv->own_thread) {
+                                        if (pipe(new_priv->pipe) < 0) {
+                                                gf_log(this->name, GF_LOG_ERROR,
+                                                       "could not create pipe");
+                                        }
+                                        ret = socket_spawn(new_trans);
+                                        if (ret) {
+                                                gf_log(this->name, GF_LOG_ERROR,
+                                                       "could not spawn thread");
+                                                sys_close (new_priv->pipe[0]);
+                                                sys_close (new_priv->pipe[1]);
+                                        }
+                                }  else {
+                                        new_priv->idx =
+                                                event_register (ctx->event_pool,
+                                                                new_sock,
+                                                           socket_event_handler,
+                                                                new_trans,
+                                                                1, 0);
+                                        if (new_priv->idx == -1) {
+                                                ret = -1;
+                                                gf_log(this->name, GF_LOG_ERROR,
+                                                       "failed to register the socket with event");
+                                        }
+                                }
 
                         }
                         pthread_mutex_unlock (&new_priv->lock);
                         if (ret == -1) {
-                                gf_log (this->name, GF_LOG_WARNING,
-                                        "failed to register the socket with event");
                                 sys_close (new_sock);
+                                GF_FREE (new_trans->name);
+                                GF_FREE (new_trans);
                                 rpc_transport_unref (new_trans);
                                 goto unlock;
                         }
@@ -3200,7 +3097,14 @@ handler:
                         }
 
                         this->listener = this;
-                        socket_spawn(this);
+                        ret =  socket_spawn(this);
+                        if (ret) {
+                                gf_log(this->name, GF_LOG_ERROR,
+                                       "could not spawn thread");
+                                sys_close(priv->pipe[0]);
+                                sys_close(priv->pipe[1]);
+                                priv->sock = -1;
+                        }
                 }
                 else {
                         priv->idx = event_register (ctx->event_pool, priv->sock,