Revert "core & res_pjsip: Improve topology change handling."

This reverts commit 315eb551dbd18ecd424a2f32179d4c1f6f6edd26.

Over the past year, we've had several reports of "topology storms"
occurring where 2 external facing channels connected by one or more
local channels and bridges will get themselves in a state where
they continually send each other topology change requests.  This
usually manifests itself in no-audio calls and a flood of
"Exceptionally long queue length" messages.  It appears that this
commit is the cause so we're reverting it for now until we can
determine a more appropriate solution.

Resolves: #530
(cherry picked from commit c31cd32b8296c675f66be7a4d39e89b45c3aec2c)

diff --git a/main/channel.c b/main/channel.c
index d7bd42f2838496ffaae63c77681e98cdbf4576a1..6fda5128c9b7f678ca02867a4e0b321881fb1655 100644 (file)
--- a/main/channel.c
+++ b/main/channel.c
@@ -10970,6 +10970,15 @@ int ast_channel_request_stream_topology_change(struct ast_channel *chan,
                return -1;
        }
 
+       if (ast_stream_topology_equal(ast_channel_get_stream_topology(chan), topology)) {
+               ast_debug(2, "%s: Topologies already match. Current: %s  Requested: %s\n",
+                               ast_channel_name(chan),
+                               ast_str_tmp(256, ast_stream_topology_to_str(ast_channel_get_stream_topology(chan), &STR_TMP)),
+                               ast_str_tmp(256, ast_stream_topology_to_str(topology, &STR_TMP)));
+               ast_channel_unlock(chan);
+               return 0;
+       }
+
        ast_channel_internal_set_stream_topology_change_source(chan, change_source);
 
        res = ast_channel_tech(chan)->indicate(chan, AST_CONTROL_STREAM_TOPOLOGY_REQUEST_CHANGE, topology, sizeof(topology));

diff --git a/res/res_pjsip_session.c b/res/res_pjsip_session.c
index b5a8b3f54c36e8ad2a88b04029019b5e46e2e459..b1d2dbdf17724fa0c0c580fba2cc4eb9bf06642f 100644 (file)
--- a/res/res_pjsip_session.c
+++ b/res/res_pjsip_session.c
@@ -1935,7 +1935,15 @@ static struct ast_sip_session_media_state *resolve_refresh_media_states(
                                /* All the same state, no need to update. */
                                SCOPE_EXIT_EXPR(continue, "%s: All in the same state so nothing to do\n", session_name);
                        }
-                       if (dp_state != ca_state) {
+                       if (da_state != ca_state) {
+                               /*
+                                * Something set the CA state between the time this request was queued
+                                * and now.  The CA state wins so we don't do anything.
+                                */
+                               SCOPE_EXIT_EXPR(continue, "%s: Ignoring request to change state from %s to %s\n",
+                                       session_name, ast_stream_state2str(ca_state), ast_stream_state2str(dp_state));
+                       }
+                       if (dp_state != da_state) {
                                /* DP needs to update the state */
                                ast_stream_set_state(np_stream, dp_state);
                                SCOPE_EXIT_EXPR(continue, "%s: Changed NP stream state from %s to %s\n",
@@ -5945,7 +5953,6 @@ AST_TEST_DEFINE(test_resolve_refresh_media_states)
 
        test_media_add(expected_pending_state, "audio", AST_MEDIA_TYPE_AUDIO, AST_STREAM_STATE_SENDRECV, -1);
        test_media_add(expected_pending_state, "myvideo1", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
-       test_media_add(expected_pending_state, "myvideo2", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        test_media_add(expected_pending_state, "myvideo3", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        CHECKER();
 
@@ -5984,9 +5991,8 @@ AST_TEST_DEFINE(test_resolve_refresh_media_states)
 
        test_media_add(expected_pending_state, "audio", AST_MEDIA_TYPE_AUDIO, AST_STREAM_STATE_SENDRECV, -1);
        test_media_add(expected_pending_state, "myvideo1", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
-       test_media_add(expected_pending_state, "myvideo2", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
-       test_media_add(expected_pending_state, "myvideo4", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        test_media_add(expected_pending_state, "myvideo3", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
+       test_media_add(expected_pending_state, "myvideo4", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        CHECKER();
 
        RESET_STATE(7);
@@ -6032,7 +6038,6 @@ AST_TEST_DEFINE(test_resolve_refresh_media_states)
 
        test_media_add(expected_pending_state, "audio", AST_MEDIA_TYPE_AUDIO, AST_STREAM_STATE_SENDRECV, -1);
        test_media_add(expected_pending_state, "myvideo1", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
-       test_media_add(expected_pending_state, "myvideo2", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        test_media_add(expected_pending_state, "myvideo3", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        test_media_add(expected_pending_state, "myvideo4", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        CHECKER();
@@ -6053,8 +6058,6 @@ AST_TEST_DEFINE(test_resolve_refresh_media_states)
        test_media_add(current_active_state, "myvideo2", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_REMOVED, -1);
 
        test_media_add(expected_pending_state, "audio", AST_MEDIA_TYPE_AUDIO, AST_STREAM_STATE_SENDRECV, -1);
-       test_media_add(expected_pending_state, "myvideo1", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
-       test_media_add(expected_pending_state, "myvideo2", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        test_media_add(expected_pending_state, "myvideo3", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        test_media_add(expected_pending_state, "myvideo4", AST_MEDIA_TYPE_VIDEO, AST_STREAM_STATE_SENDRECV, -1);
        CHECKER();