AudioFlinger: add specific mutex for client lists

Add a specific mutex to protect access to mClients and
mNotificationClients lists. This avoids locking the main AudioFlinger
mutex from inside thread loops and allows not to worry about
cross deadlocks when sending a config event with status reply while
keeping the ThreadBase or AudioFlinger mutex locked.
As a way of consequence, remove notification client list passed to
processConfigEvents_l() and audioConfigChanged() as the list
can now be accessed by locking client mutex only.

Change-Id: I228022204b6709a8bb60cc96d9514a6ffe59b62e

1 files changed, 4 insertions, 15 deletions

diff --git a/services/audioflinger/Threads.h b/services/audioflinger/Threads.h
index 9578993..cc2b246 100644
--- a/services/audioflinger/Threads.h
+++ b/services/audioflinger/Threads.h
@@ -200,10 +200,7 @@ public:
                                                     status_t& status) = 0;
     virtual     status_t    setParameters(const String8& keyValuePairs);
     virtual     String8     getParameters(const String8& keys) = 0;
-    virtual     void        audioConfigChanged_l(
-                      const DefaultKeyedVector< pid_t,sp<NotificationClient> >& notificationClients,
-                      int event,
-                      int param = 0) = 0;
+    virtual     void        audioConfigChanged(int event, int param = 0) = 0;
                 // sendConfigEvent_l() must be called with ThreadBase::mLock held
                 // Can temporarily release the lock if waiting for a reply from
                 // processConfigEvents_l().
@@ -212,8 +209,7 @@ public:
                 void        sendIoConfigEvent_l(int event, int param = 0);
                 void        sendPrioConfigEvent_l(pid_t pid, pid_t tid, int32_t prio);
                 status_t    sendSetParameterConfigEvent_l(const String8& keyValuePair);
-                void        processConfigEvents_l(
-                    const DefaultKeyedVector< pid_t,sp<NotificationClient> >& notificationClients);
+                void        processConfigEvents_l();
     virtual     void        cacheParameters_l() = 0;
 
                 // see note at declaration of mStandby, mOutDevice and mInDevice
@@ -502,10 +498,7 @@ public:
                                 { return android_atomic_acquire_load(&mSuspended) > 0; }
 
     virtual     String8     getParameters(const String8& keys);
-    virtual     void        audioConfigChanged_l(
-                    const DefaultKeyedVector< pid_t,sp<NotificationClient> >& notificationClients,
-                    int event,
-                    int param = 0);
+    virtual     void        audioConfigChanged(int event, int param = 0);
                 status_t    getRenderPosition(uint32_t *halFrames, uint32_t *dspFrames);
                 // FIXME rename mixBuffer() to sinkBuffer() and remove int16_t* dependency.
                 // Consider also removing and passing an explicit mMainBuffer initialization
@@ -652,7 +645,6 @@ private:
 
     friend class AudioFlinger;      // for numerous
 
-    PlaybackThread(const Client&);
     PlaybackThread& operator = (const PlaybackThread&);
 
     status_t    addTrack_l(const sp<Track>& track);
@@ -1037,10 +1029,7 @@ public:
                                                status_t& status);
     virtual void        cacheParameters_l() {}
     virtual String8     getParameters(const String8& keys);
-    virtual void        audioConfigChanged_l(
-                    const DefaultKeyedVector< pid_t,sp<NotificationClient> >& notificationClients,
-                    int event,
-                    int param = 0);
+    virtual void        audioConfigChanged(int event, int param = 0);
             void        readInputParameters_l();
     virtual uint32_t    getInputFramesLost();