Bug 1221587: Improve logging of callback driver/switching r=padenot

--HG--
extra : commitid : 72dxUhmH4Wm

dom/media/GraphDriver.cpp

@@ -95,6 +95,12 @@ void GraphDriver::SwitchAtNextIteration(GraphDriver* aNextDriver)
   LIFECYCLE_LOG("Switching to new driver: %p (%s)",
       aNextDriver, aNextDriver->AsAudioCallbackDriver() ?
       "AudioCallbackDriver" : "SystemClockDriver");
+  if (mNextDriver &&
+      mNextDriver != GraphImpl()->CurrentDriver()) {
+    LIFECYCLE_LOG("Discarding previous next driver: %p (%s)",
+                  mNextDriver.get(), mNextDriver->AsAudioCallbackDriver() ?
+                  "AudioCallbackDriver" : "SystemClockDriver");
+  }
   SetNextDriver(aNextDriver);
 }
 
@@ -481,13 +487,13 @@ AsyncCubebTask::Run()
 
   switch(mOperation) {
     case AsyncCubebOperation::INIT: {
-      LIFECYCLE_LOG("AsyncCubebOperation::INIT\n");
+      LIFECYCLE_LOG("AsyncCubebOperation::INIT driver=%p\n", mDriver.get());
       mDriver->Init();
       mDriver->CompleteAudioContextOperations(mOperation);
       break;
     }
     case AsyncCubebOperation::SHUTDOWN: {
-      LIFECYCLE_LOG("AsyncCubebOperation::SHUTDOWN\n");
+      LIFECYCLE_LOG("AsyncCubebOperation::SHUTDOWN driver=%p\n", mDriver.get());
       mDriver->Stop();
 
       mDriver->CompleteAudioContextOperations(mOperation);
@@ -866,11 +872,11 @@ AudioCallbackDriver::DataCallback(AudioDataValue* aInputBuffer,
     // reclock the current time against the state time, here.
     mIterationEnd = mIterationStart + 0.8 * inGraph;
 
-    STREAM_LOG(LogLevel::Debug, ("interval[%ld; %ld] state[%ld; %ld] (frames: %ld) (durationMS: %u) (duration ticks: %ld)\n",
-                              (long)mIterationStart, (long)mIterationEnd,
-                              (long)stateComputedTime, (long)nextStateComputedTime,
-                              (long)aFrames, (uint32_t)durationMS,
-                              (long)(nextStateComputedTime - stateComputedTime)));
+    STREAM_LOG(LogLevel::Verbose, ("interval[%ld; %ld] state[%ld; %ld] (frames: %ld) (durationMS: %u) (duration ticks: %ld)\n",
+                                   (long)mIterationStart, (long)mIterationEnd,
+                                   (long)stateComputedTime, (long)nextStateComputedTime,
+                                   (long)aFrames, (uint32_t)durationMS,
+                                   (long)(nextStateComputedTime - stateComputedTime)));
 
     mCurrentTimeStamp = TimeStamp::Now();