Stop GraphicBufferSource's looper without locking
Before this CL, the following sequence of events could cause a deadlock:
- Binder thread: Acquires the mutex (mMutex) inside release().
- Looper thread: Blocks inside onMessageReceived() as it tries to
acquire the mutex.
- Binder thread: Calls mLooper->stop() inside release(), which waits for
the looper thread to finish executing onMessageReceived().
Test: make cts -j123 && cts-tradefed run cts-dev -m \
CtsMediaTestCases --compatibility:module-arg \
CtsMediaTestCases:include-annotation:\
android.platform.test.annotations.RequiresDevice
Bug: 74170420
Change-Id: Ie63b19107f10937f7a301fe74b38f15076cc0ed9
diff --git a/media/libstagefright/bqhelper/GraphicBufferSource.cpp b/media/libstagefright/bqhelper/GraphicBufferSource.cpp
index 87d2555..68ae8ec 100644
--- a/media/libstagefright/bqhelper/GraphicBufferSource.cpp
+++ b/media/libstagefright/bqhelper/GraphicBufferSource.cpp
@@ -421,26 +421,31 @@
}
Status GraphicBufferSource::release(){
- Mutex::Autolock autoLock(mMutex);
- if (mLooper != NULL) {
- mLooper->unregisterHandler(mReflector->id());
- mReflector.clear();
+ sp<ALooper> looper;
+ {
+ Mutex::Autolock autoLock(mMutex);
+ looper = mLooper;
+ if (mLooper != NULL) {
+ mLooper->unregisterHandler(mReflector->id());
+ mReflector.clear();
- mLooper->stop();
- mLooper.clear();
+ mLooper.clear();
+ }
+
+ ALOGV("--> release; available=%zu+%d eos=%d eosSent=%d acquired=%d",
+ mAvailableBuffers.size(), mNumAvailableUnacquiredBuffers,
+ mEndOfStream, mEndOfStreamSent, mNumOutstandingAcquires);
+
+ // Codec is no longer executing. Releasing all buffers to bq.
+ mFreeCodecBuffers.clear();
+ mSubmittedCodecBuffers.clear();
+ mLatestBuffer.mBuffer.reset();
+ mComponent.clear();
+ mExecuting = false;
}
-
- ALOGV("--> release; available=%zu+%d eos=%d eosSent=%d acquired=%d",
- mAvailableBuffers.size(), mNumAvailableUnacquiredBuffers,
- mEndOfStream, mEndOfStreamSent, mNumOutstandingAcquires);
-
- // Codec is no longer executing. Releasing all buffers to bq.
- mFreeCodecBuffers.clear();
- mSubmittedCodecBuffers.clear();
- mLatestBuffer.mBuffer.reset();
- mComponent.clear();
- mExecuting = false;
-
+ if (looper != NULL) {
+ looper->stop();
+ }
return Status::ok();
}