Move video encode accelerator IPC messages to GPU IO thread

media/gpu/media_foundation_video_encode_accelerator_win.cc

Index: media/gpu/media_foundation_video_encode_accelerator_win.cc
diff --git a/media/gpu/media_foundation_video_encode_accelerator_win.cc b/media/gpu/media_foundation_video_encode_accelerator_win.cc
index dfd27106cc9ea0047cabba1ad4854dcf9ab49d92..6d0fd0831a70492680e509903df074f3c88e4c2e 100644
--- a/media/gpu/media_foundation_video_encode_accelerator_win.cc
+++ b/media/gpu/media_foundation_video_encode_accelerator_win.cc
@@ -87,8 +87,8 @@ MediaFoundationVideoEncodeAccelerator::MediaFoundationVideoEncodeAccelerator()
 
 MediaFoundationVideoEncodeAccelerator::
     ~MediaFoundationVideoEncodeAccelerator() {
+  DCHECK(thread_checker_.CalledOnValidThread());
   DVLOG(3) << __func__;

[sandersd (OOO until July 31), 2016/10/21 01:01:00]

Nit: Prefer __func__ logging first.

[emircan, 2016/10/24 19:44:53]

Done.

-  DCHECK(sequence_checker_.CalledOnValidSequence());
 
   DCHECK(!encoder_thread_.IsRunning());
   DCHECK(!encoder_task_weak_factory_.HasWeakPtrs());
@@ -99,7 +99,7 @@ MediaFoundationVideoEncodeAccelerator::GetSupportedProfiles() {
   TRACE_EVENT0("gpu,startup",
                "MediaFoundationVideoEncodeAccelerator::GetSupportedProfiles");
   DVLOG(3) << __func__;
-  DCHECK(sequence_checker_.CalledOnValidSequence());
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   SupportedProfiles profiles;
 
@@ -136,7 +136,7 @@ bool MediaFoundationVideoEncodeAccelerator::Initialize(
            << ", input_visible_size=" << input_visible_size.ToString()
            << ", output_profile=" << output_profile
            << ", initial_bitrate=" << initial_bitrate;
-  DCHECK(sequence_checker_.CalledOnValidSequence());
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   if (PIXEL_FORMAT_I420 != format) {
     DLOG(ERROR) << "Input format not supported= "
@@ -260,7 +260,7 @@ void MediaFoundationVideoEncodeAccelerator::RequestEncodingParametersChange(
 
 void MediaFoundationVideoEncodeAccelerator::Destroy() {
   DVLOG(3) << __func__;
-  DCHECK(sequence_checker_.CalledOnValidSequence());
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   // Cancel all callbacks.
   client_ptr_factory_.reset();

[sandersd (OOO until July 31), 2016/10/21 18:41:03]

Note that this no longer has the stated side effect. It's a bit ugly to have
invalidations happening in multiple places, perhaps there should be two
different client pointers, or all invalidation should happen on one of the two
classes?

[emircan, 2016/10/24 19:44:53]

Thanks for pointing this out. I added a reset to make sure |client_| is invalid.

This method-Destroy()- is called by default dtor() in two scenarios:
- Initialize fails. Then we don't have an external |client_| and this works. 
- GPUVEA::OnWillDestoyStub() sequence. Then we have an external |client_| but it
is already invalidated by GPUVEA.

GPUVEA attaches a callback to itself on EncodeFrameFinished(), so I think it
makes sense that it owns a weakptr to itself. The problem is that this class
needs to create its own WeakPtrFactory for clients as it receives a naked ptr in
Initialize(). I can add a TODO to change that behavior in later CLs. 

The issue actually exists in V4L2VEA as well, see below.
https://cs.chromium.org/chromium/src/media/gpu/v4l2_video_decode_accelerator....

@@ -276,6 +276,16 @@ void MediaFoundationVideoEncodeAccelerator::Destroy() {
   delete this;
 }
 
+bool MediaFoundationVideoEncodeAccelerator::TryToSetupEncodeOnSeparateThread(
+    const base::WeakPtr<Client>& encode_client,
+    const scoped_refptr<base::SingleThreadTaskRunner>& encode_task_runner) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  client_ = encode_client;
+  client_task_runner_ = encode_task_runner;
+  sequence_checker_.DetachFromSequence();
+  return true;
+}
+
 // static
 void MediaFoundationVideoEncodeAccelerator::PreSandboxInitialization() {
   for (const wchar_t* mfdll : kMediaFoundationVideoEncoderDLLs)
@@ -284,7 +294,7 @@ void MediaFoundationVideoEncodeAccelerator::PreSandboxInitialization() {
 
 bool MediaFoundationVideoEncodeAccelerator::CreateHardwareEncoderMFT() {
   DVLOG(3) << __func__;
-  DCHECK(sequence_checker_.CalledOnValidSequence());
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   if (base::win::GetVersion() < base::win::VERSION_WIN8) {
     DVLOG(ERROR) << "Windows versions earlier than 8 are not supported.";
@@ -321,7 +331,7 @@ bool MediaFoundationVideoEncodeAccelerator::CreateHardwareEncoderMFT() {
 }
 
 bool MediaFoundationVideoEncodeAccelerator::InitializeInputOutputSamples() {
-  DCHECK(sequence_checker_.CalledOnValidSequence());
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   // Initialize output parameters.
   HRESULT hr = MFCreateMediaType(imf_output_media_type_.Receive());
@@ -372,7 +382,7 @@ bool MediaFoundationVideoEncodeAccelerator::InitializeInputOutputSamples() {
 }
 
 bool MediaFoundationVideoEncodeAccelerator::SetEncoderModes() {
-  DCHECK(sequence_checker_.CalledOnValidSequence());
+  DCHECK(thread_checker_.CalledOnValidThread());
 
   HRESULT hr = encoder_.QueryInterface(IID_ICodecAPI, codec_api_.ReceiveVoid());
   RETURN_ON_HR_FAILURE(hr, "Couldn't get ICodecAPI", false);