Fix some locking order issues in app_queue. This was
authorMark Michelson <mmichelson@digium.com>
Wed, 3 Sep 2008 20:16:12 +0000 (20:16 +0000)
committerMark Michelson <mmichelson@digium.com>
Wed, 3 Sep 2008 20:16:12 +0000 (20:16 +0000)
brought up by atis on IRC a while ago.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@140975 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_queue.c

index e619ad9..5bd8901 100644 (file)
@@ -984,7 +984,7 @@ static int add_to_interfaces(const char *interface)
        return 0;
 }
 
-static int interface_exists_global(const char *interface)
+static int interface_exists_global(const char *interface, int lock_queue_container)
 {
        struct call_queue *q;
        struct member *mem, tmpmem;
@@ -992,7 +992,7 @@ static int interface_exists_global(const char *interface)
        int ret = 0;
 
        ast_copy_string(tmpmem.interface, interface, sizeof(tmpmem.interface));
-       queue_iter = ao2_iterator_init(queues, 0);
+       queue_iter = ao2_iterator_init(queues, lock_queue_container ? 0 : F_AO2I_DONTLOCK);
        while ((q = ao2_iterator_next(&queue_iter))) {
                ao2_lock(q);
                mem_iter = ao2_iterator_init(q->members, 0);
@@ -1010,11 +1010,11 @@ static int interface_exists_global(const char *interface)
        return ret;
 }
 
-static int remove_from_interfaces(const char *interface)
+static int remove_from_interfaces(const char *interface, int lock_queue_container)
 {
        struct member_interface *curint;
 
-       if (interface_exists_global(interface))
+       if (interface_exists_global(interface, lock_queue_container))
                return 0;
 
        AST_LIST_LOCK(&interfaces);
@@ -1354,7 +1354,7 @@ static void rt_handle_member_record(struct call_queue *q, char *interface, const
                        if (paused_str)
                                m->paused = paused;
                        if (strcasecmp(state_interface, m->state_interface)) {
-                               remove_from_interfaces(m->state_interface);
+                               remove_from_interfaces(m->state_interface, 0);
                                ast_copy_string(m->state_interface, state_interface, sizeof(m->state_interface));
                                add_to_interfaces(m->state_interface);
                        }          
@@ -1392,7 +1392,7 @@ static void free_members(struct call_queue *q, int all)
        while ((cur = ao2_iterator_next(&mem_iter))) {
                if (all || !cur->dynamic) {
                        ao2_unlink(q->members, cur);
-                       remove_from_interfaces(cur->state_interface);
+                       remove_from_interfaces(cur->state_interface, 1);
                        q->membercount--;
                }
                ao2_ref(cur, -1);
@@ -1560,7 +1560,7 @@ static struct call_queue *find_queue_by_name_rt(const char *queuename, struct as
                if (m->dead) {
                        ast_queue_log(q->name, "REALTIME", m->interface, "REMOVEMEMBER", "%s", "");
                        ao2_unlink(q->members, m);
-                       remove_from_interfaces(m->state_interface);
+                       remove_from_interfaces(m->state_interface, 0);
                        q->membercount--;
                }
                ao2_ref(m, -1);
@@ -1643,6 +1643,7 @@ static void update_realtime_members(struct call_queue *q)
                return;
        }
 
+       ao2_lock(queues);
        ao2_lock(q);
        
        /* Temporarily set realtime  members dead so we can detect deleted ones.*/ 
@@ -1668,12 +1669,13 @@ static void update_realtime_members(struct call_queue *q)
                if (m->dead) {
                        ast_queue_log(q->name, "REALTIME", m->interface, "REMOVEMEMBER", "%s", "");
                        ao2_unlink(q->members, m);
-                       remove_from_interfaces(m->state_interface);
+                       remove_from_interfaces(m->state_interface, 0);
                        q->membercount--;
                }
                ao2_ref(m, -1);
        }
        ao2_unlock(q);
+       ao2_unlock(queues);
        ast_config_destroy(member_config);
 }
 
@@ -3980,6 +3982,7 @@ static int remove_from_queue(const char *queuename, const char *interface)
 
        ast_copy_string(tmpmem.interface, interface, sizeof(tmpmem.interface));
        if ((q = ao2_find(queues, &tmpq, OBJ_POINTER))) {
+               ao2_lock(queues);
                ao2_lock(q);
                if ((mem = ao2_find(q->members, &tmpmem, OBJ_POINTER))) {
                        /* XXX future changes should beware of this assumption!! */
@@ -3995,7 +3998,7 @@ static int remove_from_queue(const char *queuename, const char *interface)
                                "MemberName: %s\r\n",
                                q->name, mem->interface, mem->membername);
                        ao2_unlink(q->members, mem);
-                       remove_from_interfaces(mem->state_interface);
+                       remove_from_interfaces(mem->state_interface, 0);
                        ao2_ref(mem, -1);
 
                        if (queue_persistent_members)
@@ -4006,6 +4009,7 @@ static int remove_from_queue(const char *queuename, const char *interface)
                        res = RES_EXISTS;
                }
                ao2_unlock(q);
+               ao2_unlock(queues);
                queue_unref(q);
        }
 
@@ -5441,7 +5445,7 @@ static int reload_queues(int reload)
                                                cur = ao2_find(q->members, &tmpmem, OBJ_POINTER | OBJ_UNLINK);
                                                /* Only attempt removing from interfaces list if the new state_interface is different than the old one */
                                                if (cur && strcasecmp(cur->state_interface, state_interface)) {
-                                                       remove_from_interfaces(cur->state_interface);
+                                                       remove_from_interfaces(cur->state_interface, 0);
                                                }
                                                newm = create_queue_member(interface, membername, penalty, cur ? cur->paused : 0, state_interface);
                                                if (!cur || (cur && strcasecmp(cur->state_interface, state_interface)))
@@ -5469,7 +5473,7 @@ static int reload_queues(int reload)
                                        }
                                        q->membercount--;
                                        ao2_unlink(q->members, cur);
-                                       remove_from_interfaces(cur->interface);
+                                       remove_from_interfaces(cur->interface, 0);
                                        ao2_ref(cur, -1);
                                }