Asynchronous handling of remote volume updates

Remote playback information updates will be posted from the
 application thread, and sent to AudioService. Because they
 require locking the stack containing the remote playback
 information, the update should happen on AudioService's handler
 thread to avoid lock contention.

Change-Id: Ie04898295e08c16dd8ab5985fd825301e9cf1981

2 files changed, 30 insertions, 8 deletions

diff --git a/media/java/android/media/AudioService.java b/media/java/android/media/AudioService.java
index 1b47602..2e153dd 100644
--- a/media/java/android/media/AudioService.java
+++ b/media/java/android/media/AudioService.java
@@ -141,11 +141,13 @@ public class AudioService extends IAudioService.Stub implements OnFinished {
     private static final int MSG_PERSIST_MASTER_VOLUME_MUTE = 15;
     private static final int MSG_REPORT_NEW_ROUTES = 16;
     private static final int MSG_REEVALUATE_REMOTE = 17;
+    private static final int MSG_RCC_NEW_PLAYBACK_INFO = 18;
+    private static final int MSG_RCC_NEW_VOLUME_OBS = 19;
     // start of messages handled under wakelock
     //   these messages can only be queued, i.e. sent with queueMsgUnderWakeLock(),
     //   and not with sendMsg(..., ..., SENDMSG_QUEUE, ...)
-    private static final int MSG_SET_WIRED_DEVICE_CONNECTION_STATE = 18;
-    private static final int MSG_SET_A2DP_CONNECTION_STATE = 19;
+    private static final int MSG_SET_WIRED_DEVICE_CONNECTION_STATE = 20;
+    private static final int MSG_SET_A2DP_CONNECTION_STATE = 21;
     // end of messages handled under wakelock
 
     // flags for MSG_PERSIST_VOLUME indicating if current and/or last audible volume should be
@@ -3100,6 +3102,15 @@ public class AudioService extends IAudioService.Stub implements OnFinished {
                 case MSG_REEVALUATE_REMOTE:
                     onReevaluateRemote();
                     break;
+
+                case MSG_RCC_NEW_PLAYBACK_INFO:
+                    onNewPlaybackInfoForRcc(msg.arg1 /* rccId */, msg.arg2 /* key */,
+                            ((Integer)msg.obj).intValue() /* value */);
+                    break;
+                case MSG_RCC_NEW_VOLUME_OBS:
+                    onRegisterVolumeObserverForRcc(msg.arg1 /* rccId */,
+                            (IRemoteVolumeObserver)msg.obj /* rvo */);
+                    break;
             }
         }
     }
@@ -4960,15 +4971,21 @@ public class AudioService extends IAudioService.Stub implements OnFinished {
         }
     }
 
-    // FIXME send a message instead of updating the stack synchronously
     public void setPlaybackInfoForRcc(int rccId, int what, int value) {
-        if(DEBUG_RC) Log.d(TAG, "setPlaybackInfoForRcc(id="+rccId+", what="+what+",val="+value+")");
+        sendMsg(mAudioHandler, MSG_RCC_NEW_PLAYBACK_INFO, SENDMSG_QUEUE,
+                rccId /* arg1 */, what /* arg2 */, Integer.valueOf(value) /* obj */, 0 /* delay */);
+    }
+
+    // handler for MSG_RCC_NEW_PLAYBACK_INFO
+    private void onNewPlaybackInfoForRcc(int rccId, int key, int value) {
+        if(DEBUG_RC) Log.d(TAG, "onNewPlaybackInfoForRcc(id=" + rccId +
+                ", what=" + key + ",val=" + value + ")");
         synchronized(mRCStack) {
             Iterator<RemoteControlStackEntry> stackIterator = mRCStack.iterator();
             while(stackIterator.hasNext()) {
                 RemoteControlStackEntry rcse = stackIterator.next();
                 if (rcse.mRccId == rccId) {
-                    switch (what) {
+                    switch (key) {
                         case RemoteControlClient.PLAYBACKINFO_PLAYBACK_TYPE:
                             rcse.mPlaybackType = value;
                             postReevaluateRemote();
@@ -5013,7 +5030,7 @@ public class AudioService extends IAudioService.Stub implements OnFinished {
                             }
                             break;
                         default:
-                            Log.e(TAG, "unhandled key " + what + " for RCC " + rccId);
+                            Log.e(TAG, "unhandled key " + key + " for RCC " + rccId);
                             break;
                     }
                     return;
@@ -5022,8 +5039,13 @@ public class AudioService extends IAudioService.Stub implements OnFinished {
         }
     }
 
-    // FIXME send a message instead of updating the stack synchronously
     public void registerRemoteVolumeObserverForRcc(int rccId, IRemoteVolumeObserver rvo) {
+        sendMsg(mAudioHandler, MSG_RCC_NEW_VOLUME_OBS, SENDMSG_QUEUE,
+                rccId /* arg1 */, 0, rvo /* obj */, 0 /* delay */);
+    }
+
+    // handler for MSG_RCC_NEW_VOLUME_OBS
+    private void onRegisterVolumeObserverForRcc(int rccId, IRemoteVolumeObserver rvo) {
         synchronized(mRCStack) {
             Iterator<RemoteControlStackEntry> stackIterator = mRCStack.iterator();
             while(stackIterator.hasNext()) {
diff --git a/media/java/android/media/RemoteControlClient.java b/media/java/android/media/RemoteControlClient.java
index 79f9d37..4c71ace 100644
--- a/media/java/android/media/RemoteControlClient.java
+++ b/media/java/android/media/RemoteControlClient.java
@@ -1055,7 +1055,7 @@ public class RemoteControlClient
         if (mRcseId == RCSE_ID_UNREGISTERED) {
             return;
         }
-        Log.d(TAG, "sending to AudioService key=" + what + ", value=" + value);
+        //Log.d(TAG, "sending to AudioService key=" + what + ", value=" + value);
         IAudioService service = getService();
         try {
             service.setPlaybackInfoForRcc(mRcseId, what, value);