audiopolicy: Defer release of output session effects

 * Some effects modules are racy and don't tolerate being destroyed
   and immediately resurrected on the same session. This is
   the common case when switching tracks, and the use of default
   output effects makes the problem even worse. Certain apps
   which handle gapless in a sloppy way are also to blame.
 * Instead of immediately nuking the entire descriptor with the
   stream, just decrease the refcount and defer it for 10 seconds.
   If it needs resurrected, the refcount will be increased and
   the delayed release command will not shoot it in the face.

Change-Id: I068dd72c4180023a74eb9ccbe8a180f6f0683dbf

1 files changed, 39 insertions, 0 deletions

diff --git a/services/audiopolicy/service/AudioPolicyService.cpp b/services/audiopolicy/service/AudioPolicyService.cpp
index dbeed80..58cfe37 100644
--- a/services/audiopolicy/service/AudioPolicyService.cpp
+++ b/services/audiopolicy/service/AudioPolicyService.cpp
@@ -357,6 +357,13 @@ void AudioPolicyService::binderDied(const wp<IBinder>& who) {
             IPCThreadState::self()->getCallingPid());
 }
 
+void AudioPolicyService::releaseOutputSessionEffectsDelayed(
+        audio_io_handle_t output, audio_stream_type_t stream,
+        audio_unique_id_t sessionId, int delayMs)
+{
+    mAudioCommandThread->releaseOutputSessionEffectsCommand(output, stream, sessionId, delayMs);
+}
+
 static bool tryLock(Mutex& mutex)
 {
     bool locked = false;
@@ -641,6 +648,21 @@ bool AudioPolicyService::AudioCommandThread::threadLoop()
                     svc->doOnOutputSessionEffectsUpdate(data->mStream, data->mSessionId, data->mAdded);
                     mLock.lock();
                     } break;
+                case RELEASE_OUTPUT_SESSION_EFFECTS: {
+                    ReleaseOutputSessionEffectsData *data =
+                            (ReleaseOutputSessionEffectsData *)command->mParam.get();
+                    ALOGV("AudioCommandThread() processing release output session effects %d %d %d",
+                            data->mOutput, data->mStream, data->mSessionId);
+                    svc = mService.promote();
+                    if (svc == 0) {
+                        break;
+                    }
+                    mLock.unlock();
+                    svc->mAudioPolicyEffects->doReleaseOutputSessionEffects(
+                            data->mOutput, data->mStream, data->mSessionId);
+                    mLock.lock();
+                    } break;
+
 
                 default:
                     ALOGW("AudioCommandThread() unknown command %d", command->mCommand);
@@ -929,6 +951,23 @@ void AudioPolicyService::AudioCommandThread::effectSessionUpdateCommand(
     sendCommand(command);
 }
 
+void AudioPolicyService::AudioCommandThread::releaseOutputSessionEffectsCommand(
+        audio_io_handle_t output, audio_stream_type_t stream,
+        audio_unique_id_t sessionId, int delayMs)
+{
+    sp<AudioCommand> command = new AudioCommand();
+    command->mCommand = RELEASE_OUTPUT_SESSION_EFFECTS;
+    ReleaseOutputSessionEffectsData *data = new ReleaseOutputSessionEffectsData();
+    data->mOutput = output;
+    data->mStream = stream;
+    data->mSessionId = sessionId;
+    command->mParam = data;
+    ALOGV("AudioCommandThread() sending release output session effects (id=%d) for stream %d",
+            sessionId, stream);
+    sendCommand(command, delayMs);
+}
+
+
 status_t AudioPolicyService::AudioCommandThread::sendCommand(sp<AudioCommand>& command, int delayMs)
 {
     {