Revert of services/ui: Avoid thread hopping in the gpu process.

services/ui/gpu/gpu_service_internal.cc

Index: services/ui/gpu/gpu_service_internal.cc
diff --git a/services/ui/gpu/gpu_service_internal.cc b/services/ui/gpu/gpu_service_internal.cc
index 2eaf203452a8cd89d47e29901b42340924e183d5..d771c280d2ab3a09a64a845c0e4b0f8a573fef92 100644
--- a/services/ui/gpu/gpu_service_internal.cc
+++ b/services/ui/gpu/gpu_service_internal.cc
@@ -5,6 +5,7 @@
 #include "services/ui/gpu/gpu_service_internal.h"
 
 #include "base/memory/shared_memory.h"
+#include "base/synchronization/waitable_event.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
 #include "gpu/command_buffer/service/gpu_switches.h"
@@ -33,6 +34,15 @@
 #endif
 
 namespace ui {
+namespace {
+
+void EstablishGpuChannelDone(
+    mojo::ScopedMessagePipeHandle* channel_handle,
+    const GpuServiceInternal::EstablishGpuChannelCallback& callback) {
+  callback.Run(std::move(*channel_handle));
+}
+
+}  // namespace
 
 GpuServiceInternal::GpuServiceInternal(
     const gpu::GPUInfo& gpu_info,
@@ -46,13 +56,154 @@
       watchdog_thread_(watchdog_thread),
       gpu_memory_buffer_factory_(gpu_memory_buffer_factory),
       gpu_info_(gpu_info),
-      binding_(this) {
+      binding_(this) {}
+
+GpuServiceInternal::~GpuServiceInternal() {
+  // Signal this event before destroying the child process.  That way all
+  // background threads can cleanup.
+  // For example, in the renderer the RenderThread instances will be able to
+  // notice shutdown before the render process begins waiting for them to exit.
+  shutdown_event_.Signal();
+  io_thread_.Stop();
+}
+
+void GpuServiceInternal::Add(mojom::GpuServiceInternalRequest request) {
+  binding_.Close();
+  binding_.Bind(std::move(request));
+}
+
+void GpuServiceInternal::EstablishGpuChannelInternal(
+    int32_t client_id,
+    uint64_t client_tracing_id,
+    bool preempts,
+    bool allow_view_command_buffers,
+    bool allow_real_time_streams,
+    const EstablishGpuChannelCallback& callback) {
+  DCHECK(CalledOnValidThread());
+
+  if (!gpu_channel_manager_) {
+    callback.Run(mojo::ScopedMessagePipeHandle());
+    return;
+  }
+
+  auto* channel_handle = new mojo::ScopedMessagePipeHandle;
+  gpu_thread_.task_runner()->PostTaskAndReply(
+      FROM_HERE,
+      base::Bind(&GpuServiceInternal::EstablishGpuChannelOnGpuThread,
+                 base::Unretained(this), client_id, client_tracing_id, preempts,
+                 allow_view_command_buffers, allow_real_time_streams,
+                 base::Unretained(channel_handle)),
+      base::Bind(&EstablishGpuChannelDone, base::Owned(channel_handle),
+                 callback));
+}
+
+gfx::GpuMemoryBufferHandle GpuServiceInternal::CreateGpuMemoryBuffer(
+    gfx::GpuMemoryBufferId id,
+    const gfx::Size& size,
+    gfx::BufferFormat format,
+    gfx::BufferUsage usage,
+    int client_id,
+    gpu::SurfaceHandle surface_handle) {
+  DCHECK(CalledOnValidThread());
+  return gpu_memory_buffer_factory_->CreateGpuMemoryBuffer(
+      id, size, format, usage, client_id, surface_handle);
+}
+
+void GpuServiceInternal::DestroyGpuMemoryBuffer(
+    gfx::GpuMemoryBufferId id,
+    int client_id,
+    const gpu::SyncToken& sync_token) {
+  DCHECK(CalledOnValidThread());
+
+  if (gpu_channel_manager_)
+    gpu_channel_manager_->DestroyGpuMemoryBuffer(id, client_id, sync_token);
+}
+
+void GpuServiceInternal::DidCreateOffscreenContext(const GURL& active_url) {
+  NOTIMPLEMENTED();
+}
+
+void GpuServiceInternal::DidDestroyChannel(int client_id) {
+  media_service_->RemoveChannel(client_id);
+  NOTIMPLEMENTED();
+}
+
+void GpuServiceInternal::DidDestroyOffscreenContext(const GURL& active_url) {
+  NOTIMPLEMENTED();
+}
+
+void GpuServiceInternal::DidLoseContext(bool offscreen,
+                                        gpu::error::ContextLostReason reason,
+                                        const GURL& active_url) {
+  NOTIMPLEMENTED();
+}
+
+void GpuServiceInternal::StoreShaderToDisk(int client_id,
+                                           const std::string& key,
+                                           const std::string& shader) {
+  NOTIMPLEMENTED();
+}
+
+#if defined(OS_WIN)
+void GpuServiceInternal::SendAcceleratedSurfaceCreatedChildWindow(
+    gpu::SurfaceHandle parent_window,
+    gpu::SurfaceHandle child_window) {
+  ::SetParent(child_window, parent_window);
+}
+#endif
+
+void GpuServiceInternal::SetActiveURL(const GURL& url) {
+  // TODO(penghuang): implement this function.
+}
+
+void GpuServiceInternal::InitializeOnGpuThread(base::WaitableEvent* event) {
+  gpu_info_.video_decode_accelerator_capabilities =
+      media::GpuVideoDecodeAccelerator::GetCapabilities(gpu_preferences_);
+  gpu_info_.video_encode_accelerator_supported_profiles =
+      media::GpuVideoEncodeAccelerator::GetSupportedProfiles(gpu_preferences_);
+  gpu_info_.jpeg_decode_accelerator_supported =
+      media::GpuJpegDecodeAccelerator::IsSupported();
+
+  DCHECK(!owned_sync_point_manager_);
+  const bool allow_threaded_wait = false;
+  owned_sync_point_manager_.reset(
+      new gpu::SyncPointManager(allow_threaded_wait));
+
+  // Defer creation of the render thread. This is to prevent it from handling
+  // IPC messages before the sandbox has been enabled and all other necessary
+  // initialization has succeeded.
+  gpu_channel_manager_.reset(new gpu::GpuChannelManager(
+      gpu_preferences_, this, watchdog_thread_,
+      base::ThreadTaskRunnerHandle::Get().get(), io_thread_.task_runner().get(),
+      &shutdown_event_, owned_sync_point_manager_.get(),
+      gpu_memory_buffer_factory_));
+
+  media_service_.reset(new media::MediaService(gpu_channel_manager_.get()));
+  event->Signal();
+}
+
+void GpuServiceInternal::EstablishGpuChannelOnGpuThread(
+    int client_id,
+    uint64_t client_tracing_id,
+    bool preempts,
+    bool allow_view_command_buffers,
+    bool allow_real_time_streams,
+    mojo::ScopedMessagePipeHandle* channel_handle) {
+  if (gpu_channel_manager_) {
+    auto handle = gpu_channel_manager_->EstablishChannel(
+        client_id, client_tracing_id, preempts, allow_view_command_buffers,
+        allow_real_time_streams);
+    channel_handle->reset(handle.mojo_handle);
+    media_service_->AddChannel(client_id);
+  }
+}
+
+void GpuServiceInternal::Initialize(const InitializeCallback& callback) {
+  DCHECK(CalledOnValidThread());
   base::Thread::Options thread_options(base::MessageLoop::TYPE_DEFAULT, 0);
   thread_options.priority = base::ThreadPriority::NORMAL;
   CHECK(gpu_thread_.StartWithOptions(thread_options));
 
-  // TODO(sad): We do not need the IO thread once gpu has a separate process. It
-  // should be possible to use |main_task_runner_| for doing IO tasks.
   thread_options = base::Thread::Options(base::MessageLoop::TYPE_IO, 0);
   thread_options.priority = base::ThreadPriority::NORMAL;
 #if defined(OS_ANDROID)
@@ -61,121 +212,14 @@
   thread_options.priority = base::ThreadPriority::DISPLAY;
 #endif
   CHECK(io_thread_.StartWithOptions(thread_options));
-}
-
-GpuServiceInternal::~GpuServiceInternal() {
-  if (binding_.is_bound()) {
-    // Tear down the binding in the gpu thread.
-    gpu_thread_.task_runner()->PostTask(FROM_HERE,
-        base::Bind(&mojo::Binding<mojom::GpuServiceInternal>::Close,
-                   base::Unretained(&binding_)));
-    gpu_thread_.Stop();
-  }
-
-  // Signal this event before destroying the child process.  That way all
-  // background threads can cleanup.
-  // For example, in the renderer the RenderThread instances will be able to
-  // notice shutdown before the render process begins waiting for them to exit.
-  shutdown_event_.Signal();
-  io_thread_.Stop();
-}
-
-void GpuServiceInternal::Add(mojom::GpuServiceInternalRequest request) {
-  // Unretained() is OK here since the thread/task runner is owned by |this|.
+
+  base::WaitableEvent event(base::WaitableEvent::ResetPolicy::MANUAL,
+                            base::WaitableEvent::InitialState::NOT_SIGNALED);
   gpu_thread_.task_runner()->PostTask(
-      FROM_HERE,
-      base::Bind(&GpuServiceInternal::BindOnGpuThread, base::Unretained(this),
-                 base::Passed(std::move(request))));
-}
-
-void GpuServiceInternal::BindOnGpuThread(
-    mojom::GpuServiceInternalRequest request) {
-  binding_.Close();
-  binding_.Bind(std::move(request));
-}
-
-gfx::GpuMemoryBufferHandle GpuServiceInternal::CreateGpuMemoryBuffer(
-    gfx::GpuMemoryBufferId id,
-    const gfx::Size& size,
-    gfx::BufferFormat format,
-    gfx::BufferUsage usage,
-    int client_id,
-    gpu::SurfaceHandle surface_handle) {
-  DCHECK(gpu_thread_.task_runner()->BelongsToCurrentThread());
-  return gpu_memory_buffer_factory_->CreateGpuMemoryBuffer(
-      id, size, format, usage, client_id, surface_handle);
-}
-
-void GpuServiceInternal::DestroyGpuMemoryBuffer(
-    gfx::GpuMemoryBufferId id,
-    int client_id,
-    const gpu::SyncToken& sync_token) {
-  DCHECK(gpu_thread_.task_runner()->BelongsToCurrentThread());
-  if (gpu_channel_manager_)
-    gpu_channel_manager_->DestroyGpuMemoryBuffer(id, client_id, sync_token);
-}
-
-void GpuServiceInternal::DidCreateOffscreenContext(const GURL& active_url) {
-  NOTIMPLEMENTED();
-}
-
-void GpuServiceInternal::DidDestroyChannel(int client_id) {
-  media_service_->RemoveChannel(client_id);
-  NOTIMPLEMENTED();
-}
-
-void GpuServiceInternal::DidDestroyOffscreenContext(const GURL& active_url) {
-  NOTIMPLEMENTED();
-}
-
-void GpuServiceInternal::DidLoseContext(bool offscreen,
-                                        gpu::error::ContextLostReason reason,
-                                        const GURL& active_url) {
-  NOTIMPLEMENTED();
-}
-
-void GpuServiceInternal::StoreShaderToDisk(int client_id,
-                                           const std::string& key,
-                                           const std::string& shader) {
-  NOTIMPLEMENTED();
-}
-
-#if defined(OS_WIN)
-void GpuServiceInternal::SendAcceleratedSurfaceCreatedChildWindow(
-    gpu::SurfaceHandle parent_window,
-    gpu::SurfaceHandle child_window) {
-  ::SetParent(child_window, parent_window);
-}
-#endif
-
-void GpuServiceInternal::SetActiveURL(const GURL& url) {
-  // TODO(penghuang): implement this function.
-}
-
-void GpuServiceInternal::Initialize(const InitializeCallback& callback) {
-  DCHECK(gpu_thread_.task_runner()->BelongsToCurrentThread());
-  gpu_info_.video_decode_accelerator_capabilities =
-      media::GpuVideoDecodeAccelerator::GetCapabilities(gpu_preferences_);
-  gpu_info_.video_encode_accelerator_supported_profiles =
-      media::GpuVideoEncodeAccelerator::GetSupportedProfiles(gpu_preferences_);
-  gpu_info_.jpeg_decode_accelerator_supported =
-      media::GpuJpegDecodeAccelerator::IsSupported();
-
-  DCHECK(!owned_sync_point_manager_);
-  const bool allow_threaded_wait = false;
-  owned_sync_point_manager_.reset(
-      new gpu::SyncPointManager(allow_threaded_wait));
-
-  // Defer creation of the render thread. This is to prevent it from handling
-  // IPC messages before the sandbox has been enabled and all other necessary
-  // initialization has succeeded.
-  gpu_channel_manager_.reset(new gpu::GpuChannelManager(
-      gpu_preferences_, this, watchdog_thread_,
-      base::ThreadTaskRunnerHandle::Get().get(), io_thread_.task_runner().get(),
-      &shutdown_event_, owned_sync_point_manager_.get(),
-      gpu_memory_buffer_factory_));
-
-  media_service_.reset(new media::MediaService(gpu_channel_manager_.get()));
+      FROM_HERE, base::Bind(&GpuServiceInternal::InitializeOnGpuThread,
+                            base::Unretained(this), &event));
+  event.Wait();
+
   callback.Run(gpu_info_);
 }
 
@@ -184,23 +228,12 @@
     uint64_t client_tracing_id,
     bool is_gpu_host,
     const EstablishGpuChannelCallback& callback) {
-  DCHECK(gpu_thread_.task_runner()->BelongsToCurrentThread());
-
-  if (!gpu_channel_manager_) {
-    callback.Run(mojo::ScopedMessagePipeHandle());
-    return;
-  }
-
   const bool preempts = is_gpu_host;
   const bool allow_view_command_buffers = is_gpu_host;
   const bool allow_real_time_streams = is_gpu_host;
-  mojo::ScopedMessagePipeHandle channel_handle;
-  IPC::ChannelHandle handle = gpu_channel_manager_->EstablishChannel(
-      client_id, client_tracing_id, preempts, allow_view_command_buffers,
-      allow_real_time_streams);
-  channel_handle.reset(handle.mojo_handle);
-  media_service_->AddChannel(client_id);
-  callback.Run(std::move(channel_handle));
+  EstablishGpuChannelInternal(client_id, client_tracing_id, preempts,
+                              allow_view_command_buffers,
+                              allow_real_time_streams, callback);
 }
 
 }  // namespace ui