gpu/gles2_conform_support/egl/context.cc - chromium/src.git - Git at Google

 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "gpu/gles2_conform_support/egl/context.h"

 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "gpu/command_buffer/client/gles2_implementation.h"
 #include "gpu/command_buffer/client/gles2_lib.h"
 #include "gpu/command_buffer/client/shared_memory_limits.h"
 #include "gpu/command_buffer/client/transfer_buffer.h"
 #include "gpu/command_buffer/service/context_group.h"
 #include "gpu/command_buffer/service/mailbox_manager.h"
 #include "gpu/command_buffer/service/memory_tracking.h"
 #include "gpu/command_buffer/service/transfer_buffer_manager.h"
 #include "gpu/gles2_conform_support/egl/config.h"
 #include "gpu/gles2_conform_support/egl/display.h"
 #include "gpu/gles2_conform_support/egl/surface.h"
 #include "gpu/gles2_conform_support/egl/thread_state.h"
 #include "ui/gl/init/gl_factory.h"

 // The slight complexification in this file comes from following properties:
 // 1) Command buffer connection (context) can not be established without a
 // GLSurface. EGL Context can be created independent of a surface.  This is why
 // the connection is created only during first MakeCurrent.
 // 2) Command buffer MakeCurrent calls need the real gl context and surface be
 // current.
 // 3) Client can change real EGL context behind the scenes and then still expect
 // command buffer MakeCurrent re-set the command buffer context. This is why all
 // MakeCurrent calls must actually reset the real context, even though command
 // buffer current context does not change.
 // 4) EGL context can be destroyed without surface, but command buffer would
 // need the surface to run various cleanups. If context is destroyed
 // surfaceless, the context is marked lost before destruction. This is avoided
 // if possible, since command buffer at the time of writing prints out debug
 // text in this case.

 namespace {
 const int32_t kCommandBufferSize = 1024 * 1024;
 const int32_t kTransferBufferSize = 512 * 1024;
 const bool kBindGeneratesResources = true;
 const bool kLoseContextWhenOutOfMemory = false;
 const bool kSupportClientSideArrays = true;
 }

 namespace egl {
 Context::Context(Display* display, const Config* config)
     : display_(display),
       config_(config),
       is_current_in_some_thread_(false),
       is_destroyed_(false),
       gpu_driver_bug_workarounds_(base::CommandLine::ForCurrentProcess()) {
 }

 Context::~Context() {
   // We might not have a surface, so we must lose the context.  Cleanup will
   // execute GL commands otherwise. TODO: if shared contexts are ever
   // implemented, this will leak the GL resources. For pbuffer contexts, one
   // could track the last current surface or create a surface for destroying
   // purposes only. Other option would be to make the service usable without
   // surface.
   if (HasService()) {
     if (!WasServiceContextLost())
       MarkServiceContextLost();
     DestroyService();
   }
 }

 void Context::MarkDestroyed() {
   is_destroyed_ = true;
 }

 bool Context::SwapBuffers(Surface* current_surface) {
   DCHECK(HasService() && is_current_in_some_thread_);
   if (WasServiceContextLost())
     return false;
   client_gl_context_->SwapBuffers();
   return true;
 }

 bool Context::MakeCurrent(Context* current_context,
                           Surface* current_surface,
                           Context* new_context,
                           Surface* new_surface) {
   if (!new_context && !current_context) {
     return true;
   }
   bool cleanup_old_current_context = false;
   if (current_context) {
     if (current_context->Flush(current_surface->gl_surface()))
       cleanup_old_current_context = new_context != current_context;
   }

   if (new_context) {
     if (!new_context->IsCompatibleSurface(new_surface))
       return false;

     if (new_context->HasService()) {
       if (new_context->WasServiceContextLost())
         return false;
       if (new_context != current_context) {
         // If Flush did not set the current context, set it now. Otherwise
         // calling into the decoder is not ok.
         if (!new_context->gl_context_->MakeCurrent(new_surface->gl_surface())) {
           new_context->MarkServiceContextLost();
           return false;
         }
       }
       if (new_context != current_context || new_surface != current_surface)
         new_context->decoder_->SetSurface(new_surface->gl_surface());
       if (!new_context->decoder_->MakeCurrent()) {
         new_context->MarkServiceContextLost();
         return false;
       }
     } else {
       if (!new_context->CreateService(new_surface->gl_surface())) {
         return false;
       }
     }
   }

   // The current_surface will be released when MakeCurrent succeeds.
   // Cleanup in this case only.
   if (cleanup_old_current_context) {
     if (current_context->is_destroyed_ && current_surface != new_surface) {
       current_context->gl_context_->MakeCurrent(current_surface->gl_surface());
       // If we are releasing the context and we have one ref, it means that the
       // ref will be lost and the object will be destroyed.  Destroy the service
       // explicitly here, so that cleanup can happen and client GL
       // implementation does not print errors.
       current_context->DestroyService();
     } else {
       current_context->decoder_->ReleaseSurface();
     }
   }

   return true;
 }

 bool Context::ValidateAttributeList(const EGLint* attrib_list) {
   if (attrib_list) {
     for (int i = 0; attrib_list[i] != EGL_NONE; attrib_list += 2) {
       switch (attrib_list[i]) {
         case EGL_CONTEXT_CLIENT_VERSION:
           break;
         default:
           return false;
       }
     }
   }
   return true;
 }

 void Context::SetGpuControlClient(gpu::GpuControlClient*) {
   // The client is not currently called, so don't store it.
 }

 gpu::Capabilities Context::GetCapabilities() {
   return decoder_->GetCapabilities();
 }

 int32_t Context::CreateImage(ClientBuffer buffer,
                              size_t width,
                              size_t height,
                              unsigned internalformat) {
   NOTIMPLEMENTED();
   return -1;
 }

 void Context::DestroyImage(int32_t id) {
   NOTIMPLEMENTED();
 }

 int32_t Context::CreateGpuMemoryBufferImage(size_t width,
                                             size_t height,
                                             unsigned internalformat,
                                             unsigned usage) {
   NOTIMPLEMENTED();
   return -1;
 }

 void Context::SignalQuery(uint32_t query, const base::Closure& callback) {
   NOTIMPLEMENTED();
 }

 void Context::SetLock(base::Lock*) {
   NOTIMPLEMENTED();
 }

 void Context::EnsureWorkVisible() {
   // This is only relevant for out-of-process command buffers.
 }

 gpu::CommandBufferNamespace Context::GetNamespaceID() const {
   return gpu::CommandBufferNamespace::IN_PROCESS;
 }

 gpu::CommandBufferId Context::GetCommandBufferID() const {
   return gpu::CommandBufferId();
 }

 int32_t Context::GetExtraCommandBufferData() const {
   return 0;
 }

 uint64_t Context::GenerateFenceSyncRelease() {
   return display_->GenerateFenceSyncRelease();
 }

 bool Context::IsFenceSyncRelease(uint64_t release) {
   return display_->IsFenceSyncRelease(release);
 }

 bool Context::IsFenceSyncFlushed(uint64_t release) {
   return display_->IsFenceSyncFlushed(release);
 }

 bool Context::IsFenceSyncFlushReceived(uint64_t release) {
   return display_->IsFenceSyncFlushReceived(release);
 }

 void Context::SignalSyncToken(const gpu::SyncToken& sync_token,
                               const base::Closure& callback) {
   NOTIMPLEMENTED();
 }

 bool Context::CanWaitUnverifiedSyncToken(const gpu::SyncToken* sync_token) {
   return false;
 }

 void Context::ApplyCurrentContext(gl::GLSurface* current_surface) {
   DCHECK(HasService());
   // The current_surface will be the same as
   // the surface of the decoder. We can not DCHECK as there is
   // no accessor.
   if (!WasServiceContextLost()) {
     if (!gl_context_->MakeCurrent(current_surface))
       MarkServiceContextLost();
   }
   gles2::SetGLContext(client_gl_context_.get());
 }

 void Context::ApplyContextReleased() {
   gles2::SetGLContext(nullptr);
 }

 bool Context::CreateService(gl::GLSurface* gl_surface) {
   scoped_refptr<gpu::TransferBufferManager> transfer_buffer_manager(
       new gpu::TransferBufferManager(nullptr));
   transfer_buffer_manager->Initialize();

   std::unique_ptr<gpu::CommandBufferService> command_buffer(
       new gpu::CommandBufferService(transfer_buffer_manager.get()));

   scoped_refptr<gpu::gles2::FeatureInfo> feature_info(
       new gpu::gles2::FeatureInfo(gpu_driver_bug_workarounds_));
   scoped_refptr<gpu::gles2::ContextGroup> group(new gpu::gles2::ContextGroup(
       gpu_preferences_, nullptr, nullptr,
       new gpu::gles2::ShaderTranslatorCache(gpu_preferences_),
       new gpu::gles2::FramebufferCompletenessCache, feature_info, true,
       nullptr));

   std::unique_ptr<gpu::gles2::GLES2Decoder> decoder(
       gpu::gles2::GLES2Decoder::Create(group.get()));
   if (!decoder.get())
     return false;

   std::unique_ptr<gpu::CommandExecutor> command_executor(
       new gpu::CommandExecutor(command_buffer.get(), decoder.get(),
                                decoder.get()));

   decoder->set_engine(command_executor.get());

   scoped_refptr<gl::GLContext> gl_context(
       gl::init::CreateGLContext(nullptr, gl_surface, gl::PreferDiscreteGpu));
   if (!gl_context)
     return false;

   gl_context->MakeCurrent(gl_surface);

   gpu::gles2::ContextCreationAttribHelper helper;
   config_->GetAttrib(EGL_ALPHA_SIZE, &helper.alpha_size);
   config_->GetAttrib(EGL_DEPTH_SIZE, &helper.depth_size);
   config_->GetAttrib(EGL_STENCIL_SIZE, &helper.stencil_size);

   helper.buffer_preserved = false;
   helper.bind_generates_resource = kBindGeneratesResources;
   helper.fail_if_major_perf_caveat = false;
   helper.lose_context_when_out_of_memory = kLoseContextWhenOutOfMemory;
   helper.context_type = gpu::gles2::CONTEXT_TYPE_OPENGLES2;
   helper.offscreen_framebuffer_size = gl_surface->GetSize();

   if (!decoder->Initialize(gl_surface, gl_context.get(),
                            gl_surface->IsOffscreen(),
                            gpu::gles2::DisallowedFeatures(), helper)) {
     return false;
   }

   command_buffer->SetPutOffsetChangeCallback(
       base::Bind(&gpu::CommandExecutor::PutChanged,
                  base::Unretained(command_executor.get())));
   command_buffer->SetGetBufferChangeCallback(
       base::Bind(&gpu::CommandExecutor::SetGetBuffer,
                  base::Unretained(command_executor.get())));

   std::unique_ptr<gpu::gles2::GLES2CmdHelper> gles2_cmd_helper(
       new gpu::gles2::GLES2CmdHelper(command_buffer.get()));
   if (!gles2_cmd_helper->Initialize(kCommandBufferSize)) {
     decoder->Destroy(true);
     return false;
   }

   std::unique_ptr<gpu::TransferBuffer> transfer_buffer(
       new gpu::TransferBuffer(gles2_cmd_helper.get()));

   gles2_cmd_helper_.reset(gles2_cmd_helper.release());
   transfer_buffer_.reset(transfer_buffer.release());
   command_buffer_.reset(command_buffer.release());
   command_executor_.reset(command_executor.release());
   decoder_.reset(decoder.release());
   gl_context_ = gl_context.get();

   std::unique_ptr<gpu::gles2::GLES2Implementation> context(
       new gpu::gles2::GLES2Implementation(
           gles2_cmd_helper_.get(), nullptr, transfer_buffer_.get(),
           kBindGeneratesResources, kLoseContextWhenOutOfMemory,
           kSupportClientSideArrays, this));

   if (!context->Initialize(kTransferBufferSize, kTransferBufferSize / 2,
                            kTransferBufferSize * 2,
                            gpu::SharedMemoryLimits::kNoLimit)) {
     DestroyService();
     return false;
   }

   context->EnableFeatureCHROMIUM("pepper3d_allow_buffers_on_multiple_targets");
   context->EnableFeatureCHROMIUM("pepper3d_support_fixed_attribs");
   client_gl_context_.reset(context.release());
   return true;
 }

 void Context::DestroyService() {
   DCHECK(HasService());
   bool have_context = !WasServiceContextLost();
   // The client gl interface might still be set to current global
   // interface. This will be cleaned up in ApplyContextReleased
   // with AutoCurrentContextRestore.
   client_gl_context_.reset();
   gl_context_ = nullptr;

   transfer_buffer_.reset();
   command_executor_.reset();
   if (decoder_)
     decoder_->Destroy(have_context);
   decoder_.reset();
   gles2_cmd_helper_.reset();
   command_buffer_.reset();
 }

 bool Context::HasService() const {
   return decoder_ != nullptr;
 }

 void Context::MarkServiceContextLost() {
   decoder_->GetContextGroup()->LoseContexts(gpu::error::kMakeCurrentFailed);
 }

 bool Context::WasServiceContextLost() const {
   return decoder_->WasContextLost();
 }

 bool Context::IsCompatibleSurface(Surface* surface) const {
   // Inspect current_surface->config() instead of gl_surface()->IsOffscreen()
   // because GTF windowless window surfaces might be emulated with offscreen
   // surfaces.
   EGLint value = EGL_NONE;
   config_->GetAttrib(EGL_SURFACE_TYPE, &value);
   bool context_config_is_offscreen = (value & EGL_PBUFFER_BIT) != 0;
   surface->config()->GetAttrib(EGL_SURFACE_TYPE, &value);
   bool surface_config_is_offscreen = (value & EGL_PBUFFER_BIT) != 0;
   return surface_config_is_offscreen == context_config_is_offscreen;
 }

 bool Context::Flush(gl::GLSurface* gl_surface) {
   if (WasServiceContextLost())
     return false;
   if (!gl_context_->MakeCurrent(gl_surface)) {
     MarkServiceContextLost();
     return false;
   }
   client_gl_context_->Flush();
   return true;
 }

 }  // namespace egl
	// Copyright (c) 2016 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "gpu/gles2_conform_support/egl/context.h"

	#include "base/bind.h"
	#include "base/bind_helpers.h"
	#include "base/command_line.h"
	#include "gpu/command_buffer/client/gles2_implementation.h"
	#include "gpu/command_buffer/client/gles2_lib.h"
	#include "gpu/command_buffer/client/shared_memory_limits.h"
	#include "gpu/command_buffer/client/transfer_buffer.h"
	#include "gpu/command_buffer/service/context_group.h"
	#include "gpu/command_buffer/service/mailbox_manager.h"
	#include "gpu/command_buffer/service/memory_tracking.h"
	#include "gpu/command_buffer/service/transfer_buffer_manager.h"
	#include "gpu/gles2_conform_support/egl/config.h"
	#include "gpu/gles2_conform_support/egl/display.h"
	#include "gpu/gles2_conform_support/egl/surface.h"
	#include "gpu/gles2_conform_support/egl/thread_state.h"
	#include "ui/gl/init/gl_factory.h"

	// The slight complexification in this file comes from following properties:
	// 1) Command buffer connection (context) can not be established without a
	// GLSurface. EGL Context can be created independent of a surface. This is why
	// the connection is created only during first MakeCurrent.
	// 2) Command buffer MakeCurrent calls need the real gl context and surface be
	// current.
	// 3) Client can change real EGL context behind the scenes and then still expect
	// command buffer MakeCurrent re-set the command buffer context. This is why all
	// MakeCurrent calls must actually reset the real context, even though command
	// buffer current context does not change.
	// 4) EGL context can be destroyed without surface, but command buffer would
	// need the surface to run various cleanups. If context is destroyed
	// surfaceless, the context is marked lost before destruction. This is avoided
	// if possible, since command buffer at the time of writing prints out debug
	// text in this case.

	namespace {
	const int32_t kCommandBufferSize = 1024 * 1024;
	const int32_t kTransferBufferSize = 512 * 1024;
	const bool kBindGeneratesResources = true;
	const bool kLoseContextWhenOutOfMemory = false;
	const bool kSupportClientSideArrays = true;
	}

	namespace egl {
	Context::Context(Display* display, const Config* config)
	: display_(display),
	config_(config),
	is_current_in_some_thread_(false),
	is_destroyed_(false),
	gpu_driver_bug_workarounds_(base::CommandLine::ForCurrentProcess()) {
	}

	Context::~Context() {
	// We might not have a surface, so we must lose the context. Cleanup will
	// execute GL commands otherwise. TODO: if shared contexts are ever
	// implemented, this will leak the GL resources. For pbuffer contexts, one
	// could track the last current surface or create a surface for destroying
	// purposes only. Other option would be to make the service usable without
	// surface.
	if (HasService()) {
	if (!WasServiceContextLost())
	MarkServiceContextLost();
	DestroyService();
	}
	}

	void Context::MarkDestroyed() {
	is_destroyed_ = true;
	}

	bool Context::SwapBuffers(Surface* current_surface) {
	DCHECK(HasService() && is_current_in_some_thread_);
	if (WasServiceContextLost())
	return false;
	client_gl_context_->SwapBuffers();
	return true;
	}

	bool Context::MakeCurrent(Context* current_context,
	Surface* current_surface,
	Context* new_context,
	Surface* new_surface) {
	if (!new_context && !current_context) {
	return true;
	}
	bool cleanup_old_current_context = false;
	if (current_context) {
	if (current_context->Flush(current_surface->gl_surface()))
	cleanup_old_current_context = new_context != current_context;
	}

	if (new_context) {
	if (!new_context->IsCompatibleSurface(new_surface))
	return false;

	if (new_context->HasService()) {
	if (new_context->WasServiceContextLost())
	return false;
	if (new_context != current_context) {
	// If Flush did not set the current context, set it now. Otherwise
	// calling into the decoder is not ok.
	if (!new_context->gl_context_->MakeCurrent(new_surface->gl_surface())) {
	new_context->MarkServiceContextLost();
	return false;
	}
	}
	if (new_context != current_context \|\| new_surface != current_surface)
	new_context->decoder_->SetSurface(new_surface->gl_surface());
	if (!new_context->decoder_->MakeCurrent()) {
	new_context->MarkServiceContextLost();
	return false;
	}
	} else {
	if (!new_context->CreateService(new_surface->gl_surface())) {
	return false;
	}
	}
	}

	// The current_surface will be released when MakeCurrent succeeds.
	// Cleanup in this case only.
	if (cleanup_old_current_context) {
	if (current_context->is_destroyed_ && current_surface != new_surface) {
	current_context->gl_context_->MakeCurrent(current_surface->gl_surface());
	// If we are releasing the context and we have one ref, it means that the
	// ref will be lost and the object will be destroyed. Destroy the service
	// explicitly here, so that cleanup can happen and client GL
	// implementation does not print errors.
	current_context->DestroyService();
	} else {
	current_context->decoder_->ReleaseSurface();
	}
	}

	return true;
	}

	bool Context::ValidateAttributeList(const EGLint* attrib_list) {
	if (attrib_list) {
	for (int i = 0; attrib_list[i] != EGL_NONE; attrib_list += 2) {
	switch (attrib_list[i]) {
	case EGL_CONTEXT_CLIENT_VERSION:
	break;
	default:
	return false;
	}
	}
	}
	return true;
	}

	void Context::SetGpuControlClient(gpu::GpuControlClient*) {
	// The client is not currently called, so don't store it.
	}

	gpu::Capabilities Context::GetCapabilities() {
	return decoder_->GetCapabilities();
	}

	int32_t Context::CreateImage(ClientBuffer buffer,
	size_t width,
	size_t height,
	unsigned internalformat) {
	NOTIMPLEMENTED();
	return -1;
	}

	void Context::DestroyImage(int32_t id) {
	NOTIMPLEMENTED();
	}

	int32_t Context::CreateGpuMemoryBufferImage(size_t width,
	size_t height,
	unsigned internalformat,
	unsigned usage) {
	NOTIMPLEMENTED();
	return -1;
	}

	void Context::SignalQuery(uint32_t query, const base::Closure& callback) {
	NOTIMPLEMENTED();
	}

	void Context::SetLock(base::Lock*) {
	NOTIMPLEMENTED();
	}

	void Context::EnsureWorkVisible() {
	// This is only relevant for out-of-process command buffers.
	}

	gpu::CommandBufferNamespace Context::GetNamespaceID() const {
	return gpu::CommandBufferNamespace::IN_PROCESS;
	}

	gpu::CommandBufferId Context::GetCommandBufferID() const {
	return gpu::CommandBufferId();
	}

	int32_t Context::GetExtraCommandBufferData() const {
	return 0;
	}

	uint64_t Context::GenerateFenceSyncRelease() {
	return display_->GenerateFenceSyncRelease();
	}

	bool Context::IsFenceSyncRelease(uint64_t release) {
	return display_->IsFenceSyncRelease(release);
	}

	bool Context::IsFenceSyncFlushed(uint64_t release) {
	return display_->IsFenceSyncFlushed(release);
	}

	bool Context::IsFenceSyncFlushReceived(uint64_t release) {
	return display_->IsFenceSyncFlushReceived(release);
	}

	void Context::SignalSyncToken(const gpu::SyncToken& sync_token,
	const base::Closure& callback) {
	NOTIMPLEMENTED();
	}

	bool Context::CanWaitUnverifiedSyncToken(const gpu::SyncToken* sync_token) {
	return false;
	}

	void Context::ApplyCurrentContext(gl::GLSurface* current_surface) {
	DCHECK(HasService());
	// The current_surface will be the same as
	// the surface of the decoder. We can not DCHECK as there is
	// no accessor.
	if (!WasServiceContextLost()) {
	if (!gl_context_->MakeCurrent(current_surface))
	MarkServiceContextLost();
	}
	gles2::SetGLContext(client_gl_context_.get());
	}

	void Context::ApplyContextReleased() {
	gles2::SetGLContext(nullptr);
	}

	bool Context::CreateService(gl::GLSurface* gl_surface) {
	scoped_refptr<gpu::TransferBufferManager> transfer_buffer_manager(
	new gpu::TransferBufferManager(nullptr));
	transfer_buffer_manager->Initialize();

	std::unique_ptr<gpu::CommandBufferService> command_buffer(
	new gpu::CommandBufferService(transfer_buffer_manager.get()));

	scoped_refptr<gpu::gles2::FeatureInfo> feature_info(
	new gpu::gles2::FeatureInfo(gpu_driver_bug_workarounds_));
	scoped_refptr<gpu::gles2::ContextGroup> group(new gpu::gles2::ContextGroup(
	gpu_preferences_, nullptr, nullptr,
	new gpu::gles2::ShaderTranslatorCache(gpu_preferences_),
	new gpu::gles2::FramebufferCompletenessCache, feature_info, true,
	nullptr));

	std::unique_ptr<gpu::gles2::GLES2Decoder> decoder(
	gpu::gles2::GLES2Decoder::Create(group.get()));
	if (!decoder.get())
	return false;

	std::unique_ptr<gpu::CommandExecutor> command_executor(
	new gpu::CommandExecutor(command_buffer.get(), decoder.get(),
	decoder.get()));

	decoder->set_engine(command_executor.get());

	scoped_refptr<gl::GLContext> gl_context(
	gl::init::CreateGLContext(nullptr, gl_surface, gl::PreferDiscreteGpu));
	if (!gl_context)
	return false;

	gl_context->MakeCurrent(gl_surface);

	gpu::gles2::ContextCreationAttribHelper helper;
	config_->GetAttrib(EGL_ALPHA_SIZE, &helper.alpha_size);
	config_->GetAttrib(EGL_DEPTH_SIZE, &helper.depth_size);
	config_->GetAttrib(EGL_STENCIL_SIZE, &helper.stencil_size);

	helper.buffer_preserved = false;
	helper.bind_generates_resource = kBindGeneratesResources;
	helper.fail_if_major_perf_caveat = false;
	helper.lose_context_when_out_of_memory = kLoseContextWhenOutOfMemory;
	helper.context_type = gpu::gles2::CONTEXT_TYPE_OPENGLES2;
	helper.offscreen_framebuffer_size = gl_surface->GetSize();

	if (!decoder->Initialize(gl_surface, gl_context.get(),
	gl_surface->IsOffscreen(),
	gpu::gles2::DisallowedFeatures(), helper)) {
	return false;
	}

	command_buffer->SetPutOffsetChangeCallback(
	base::Bind(&gpu::CommandExecutor::PutChanged,
	base::Unretained(command_executor.get())));
	command_buffer->SetGetBufferChangeCallback(
	base::Bind(&gpu::CommandExecutor::SetGetBuffer,
	base::Unretained(command_executor.get())));

	std::unique_ptr<gpu::gles2::GLES2CmdHelper> gles2_cmd_helper(
	new gpu::gles2::GLES2CmdHelper(command_buffer.get()));
	if (!gles2_cmd_helper->Initialize(kCommandBufferSize)) {
	decoder->Destroy(true);
	return false;
	}

	std::unique_ptr<gpu::TransferBuffer> transfer_buffer(
	new gpu::TransferBuffer(gles2_cmd_helper.get()));

	gles2_cmd_helper_.reset(gles2_cmd_helper.release());
	transfer_buffer_.reset(transfer_buffer.release());
	command_buffer_.reset(command_buffer.release());
	command_executor_.reset(command_executor.release());
	decoder_.reset(decoder.release());
	gl_context_ = gl_context.get();

	std::unique_ptr<gpu::gles2::GLES2Implementation> context(
	new gpu::gles2::GLES2Implementation(
	gles2_cmd_helper_.get(), nullptr, transfer_buffer_.get(),
	kBindGeneratesResources, kLoseContextWhenOutOfMemory,
	kSupportClientSideArrays, this));

	if (!context->Initialize(kTransferBufferSize, kTransferBufferSize / 2,
	kTransferBufferSize * 2,
	gpu::SharedMemoryLimits::kNoLimit)) {
	DestroyService();
	return false;
	}

	context->EnableFeatureCHROMIUM("pepper3d_allow_buffers_on_multiple_targets");
	context->EnableFeatureCHROMIUM("pepper3d_support_fixed_attribs");
	client_gl_context_.reset(context.release());
	return true;
	}

	void Context::DestroyService() {
	DCHECK(HasService());
	bool have_context = !WasServiceContextLost();
	// The client gl interface might still be set to current global
	// interface. This will be cleaned up in ApplyContextReleased
	// with AutoCurrentContextRestore.
	client_gl_context_.reset();
	gl_context_ = nullptr;

	transfer_buffer_.reset();
	command_executor_.reset();
	if (decoder_)
	decoder_->Destroy(have_context);
	decoder_.reset();
	gles2_cmd_helper_.reset();
	command_buffer_.reset();
	}

	bool Context::HasService() const {
	return decoder_ != nullptr;
	}

	void Context::MarkServiceContextLost() {
	decoder_->GetContextGroup()->LoseContexts(gpu::error::kMakeCurrentFailed);
	}

	bool Context::WasServiceContextLost() const {
	return decoder_->WasContextLost();
	}

	bool Context::IsCompatibleSurface(Surface* surface) const {
	// Inspect current_surface->config() instead of gl_surface()->IsOffscreen()
	// because GTF windowless window surfaces might be emulated with offscreen
	// surfaces.
	EGLint value = EGL_NONE;
	config_->GetAttrib(EGL_SURFACE_TYPE, &value);
	bool context_config_is_offscreen = (value & EGL_PBUFFER_BIT) != 0;
	surface->config()->GetAttrib(EGL_SURFACE_TYPE, &value);
	bool surface_config_is_offscreen = (value & EGL_PBUFFER_BIT) != 0;
	return surface_config_is_offscreen == context_config_is_offscreen;
	}

	bool Context::Flush(gl::GLSurface* gl_surface) {
	if (WasServiceContextLost())
	return false;
	if (!gl_context_->MakeCurrent(gl_surface)) {
	MarkServiceContextLost();
	return false;
	}
	client_gl_context_->Flush();
	return true;
	}

	} // namespace egl