aw: Split hardware rendering into HardwareRenderer

android_webview/browser/hardware_renderer.cc

-// Copyright 2013 The Chromium Authors. All rights reserved.
+// Copyright 2014 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 "android_webview/browser/in_process_view_renderer.h"
+#include "android_webview/browser/hardware_renderer.h"
 
 #include "android_webview/browser/aw_gl_surface.h"
+#include "android_webview/browser/browser_view_renderer.h"
+#include "android_webview/browser/gl_view_renderer_manager.h"
 #include "android_webview/browser/scoped_app_gl_state_restore.h"
 #include "android_webview/common/aw_switches.h"
 #include "android_webview/public/browser/draw_gl.h"
-#include "base/android/jni_android.h"
-#include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
-#include "base/lazy_instance.h"
-#include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
-#include "base/strings/stringprintf.h"
 #include "content/public/browser/browser_thread.h"
-#include "content/public/browser/web_contents.h"
 #include "content/public/common/content_switches.h"
-#include "gpu/command_buffer/service/in_process_command_buffer.h"
-#include "third_party/skia/include/core/SkBitmap.h"
-#include "third_party/skia/include/core/SkBitmapDevice.h"
-#include "third_party/skia/include/core/SkCanvas.h"
-#include "third_party/skia/include/core/SkPicture.h"
 #include "ui/gfx/transform.h"
-#include "ui/gfx/vector2d_conversions.h"
 
-using base::android::AttachCurrentThread;
-using base::android::JavaRef;
-using base::android::ScopedJavaLocalRef;
 using content::BrowserThread;
 
 namespace android_webview {
 
 namespace {
 
-const void* kUserDataKey = &kUserDataKey;
-
-class UserData : public content::WebContents::Data {
- public:
-  UserData(InProcessViewRenderer* ptr) : instance_(ptr) {}
-  virtual ~UserData() {
-    instance_->WebContentsGone();
-  }
-
-  static InProcessViewRenderer* GetInstance(content::WebContents* contents) {
-    if (!contents)
-      return NULL;
-    UserData* data = reinterpret_cast<UserData*>(
-        contents->GetUserData(kUserDataKey));
-    return data ? data->instance_ : NULL;
-  }
-
- private:
-  InProcessViewRenderer* instance_;
-};
-
-bool HardwareEnabled() {
-  static bool g_hw_enabled = !CommandLine::ForCurrentProcess()->HasSwitch(
-      switches::kDisableWebViewGLMode);
-  return g_hw_enabled;
-}
-
-const int64 kFallbackTickTimeoutInMilliseconds = 20;
-
 // Used to calculate memory and resource allocation. Determined experimentally.
 size_t g_memory_multiplier = 10;

[benm (inactive), 2014/02/25 12:48:01]

can be overridden with switches::kTileMemoryMultiplier between 2 and 50

 size_t g_num_gralloc_limit = 150;
 const size_t kBytesPerPixel = 4;
 const size_t kMemoryAllocationStep = 5 * 1024 * 1024;
 
-base::LazyInstance<GLViewRendererManager>::Leaky g_view_renderer_manager =
-    LAZY_INSTANCE_INITIALIZER;
+base::LazyInstance<scoped_refptr<internal::DeferredGpuCommandService> >
+    g_service = LAZY_INSTANCE_INITIALIZER;
 
-class ScopedAllowGL {
- public:
-  ScopedAllowGL();
-  ~ScopedAllowGL();
+}  // namespace
 
-  static bool IsAllowed() {
-    return g_view_renderer_manager.Get().OnRenderThread() && allow_gl;
+DrawGLResult::DrawGLResult()
+    : did_draw(false), clip_contains_visible_rect(false) {}
+
+HardwareRenderer::HardwareRenderer(content::SynchronousCompositor* compositor,
+                                   BrowserViewRendererClient* client)
+    : compositor_(compositor),
+      client_(client),
+      last_egl_context_(eglGetCurrentContext()),
+      manager_key_(GLViewRendererManager::GetInstance()->NullKey()) {
+  DCHECK(compositor_);
+  DCHECK(last_egl_context_);
+}
+
+HardwareRenderer::~HardwareRenderer() {
+  ReleaseHardwareDraw();
+  DCHECK(manager_key_ == GLViewRendererManager::GetInstance()->NullKey());
+}
+
+bool HardwareRenderer::InitializeHardwareDraw() {
+  TRACE_EVENT0("android_webview", "InitializeHardwareDraw");
+  if (!g_service.Get()) {
+    g_service.Get() = new internal::DeferredGpuCommandService;
+    content::SynchronousCompositor::SetGpuService(g_service.Get());
   }
 
- private:
-  static bool allow_gl;
+  bool success = true;
+  if (!gl_surface_) {
+    scoped_refptr<AwGLSurface> gl_surface = new AwGLSurface;
+    success = compositor_->InitializeHwDraw(gl_surface);
+    if (success)
+      gl_surface_ = gl_surface;
+  }
 
-  DISALLOW_COPY_AND_ASSIGN(ScopedAllowGL);
-};
-
-ScopedAllowGL::ScopedAllowGL() {
-  DCHECK(g_view_renderer_manager.Get().OnRenderThread());
-  DCHECK(!allow_gl);
-  allow_gl = true;
+  return success;
 }
 
-ScopedAllowGL::~ScopedAllowGL() {
-  allow_gl = false;
-}
-
-bool ScopedAllowGL::allow_gl = false;
-
-void RequestProcessGLOnUIThread() {
-  if (!BrowserThread::CurrentlyOn(BrowserThread::UI)) {
-    BrowserThread::PostTask(
-        BrowserThread::UI, FROM_HERE, base::Bind(&RequestProcessGLOnUIThread));
-    return;
+void HardwareRenderer::ReleaseHardwareDraw() {

[sgurun-gerrit only, 2014/02/25 06:56:36]

consider moving this code to destructor - not much benefit of having separate
function.

+  GLViewRendererManager* mru = GLViewRendererManager::GetInstance();
+  if (manager_key_ != mru->NullKey()) {
+    mru->NoLongerExpectsDrawGL(manager_key_);
+    manager_key_ = mru->NullKey();
   }
 
-  InProcessViewRenderer* renderer = static_cast<InProcessViewRenderer*>(
-      g_view_renderer_manager.Get().GetMostRecentlyDrawn());
-  if (!renderer || !renderer->RequestProcessGL()) {
-    LOG(ERROR) << "Failed to request GL process. Deadlock likely: "
-               << !!renderer;
+  if (gl_surface_) {
+    ScopedAppGLStateRestore state_restore(
+        ScopedAppGLStateRestore::MODE_RESOURCE_MANAGEMENT);
+    internal::ScopedAllowGL allow_gl;
+

[sgurun-gerrit only, 2014/02/25 06:56:36]

Original code does a RunTasks() here. not needed anymore?

[boliu, 2014/02/25 19:02:22]

Moved RunTasks to constructor of ScopedAllowGL.

+    compositor_->ReleaseHwDraw();
+    gl_surface_ = NULL;
   }
 }
 
-class DeferredGpuCommandService
-    : public gpu::InProcessCommandBuffer::Service,
-      public base::RefCountedThreadSafe<DeferredGpuCommandService> {
- public:
-  DeferredGpuCommandService();
+DrawGLResult HardwareRenderer::DrawGL(AwDrawGLInfo* draw_info,
+                                      const DrawGLInput& input) {
+  TRACE_EVENT0("android_webview", "HardwareRenderer::DrawGL");
+  manager_key_ =
+      GLViewRendererManager::GetInstance()->DidDrawGL(manager_key_, this);
+  DrawGLResult result;
 
-  virtual void ScheduleTask(const base::Closure& task) OVERRIDE;
-  virtual void ScheduleIdleWork(const base::Closure& task) OVERRIDE;
-  virtual bool UseVirtualizedGLContexts() OVERRIDE;
-
-  void RunTasks();
-
-  virtual void AddRef() const OVERRIDE {
-    base::RefCountedThreadSafe<DeferredGpuCommandService>::AddRef();
-  }
-  virtual void Release() const OVERRIDE {
-    base::RefCountedThreadSafe<DeferredGpuCommandService>::Release();
+  // We need to watch if the current Android context has changed and enforce
+  // a clean-up in the compositor.
+  EGLContext current_context = eglGetCurrentContext();
+  if (!current_context) {
+    DLOG(ERROR) << "DrawGL called without EGLContext";
+    return result;
   }
 
- protected:
-  virtual ~DeferredGpuCommandService();
-  friend class base::RefCountedThreadSafe<DeferredGpuCommandService>;
+  // TODO(boliu): Handle context loss.
+  if (last_egl_context_ != current_context)
+    DLOG(WARNING) << "EGLContextChanged";
 
- private:
-  base::Lock tasks_lock_;
-  std::queue<base::Closure> tasks_;
-  DISALLOW_COPY_AND_ASSIGN(DeferredGpuCommandService);
-};
+  ScopedAppGLStateRestore state_restore(ScopedAppGLStateRestore::MODE_DRAW);
+  internal::ScopedAllowGL allow_gl;
 
-DeferredGpuCommandService::DeferredGpuCommandService() {}
+  if (draw_info->mode == AwDrawGLInfo::kModeProcess)
+    return result;
 
-DeferredGpuCommandService::~DeferredGpuCommandService() {
-  base::AutoLock lock(tasks_lock_);
-  DCHECK(tasks_.empty());
+  if (!InitializeHardwareDraw()) {
+    DLOG(ERROR) << "WebView hardware initialization failed";
+    return result;
+  }
+
+  // Update memory budget. This will no-op in compositor if the policy has not
+  // changed since last draw.
+  content::SynchronousCompositorMemoryPolicy policy;
+  policy.bytes_limit = g_memory_multiplier * kBytesPerPixel *
+                       input.global_visible_rect.width() *
+                       input.global_visible_rect.height();
+  // Round up to a multiple of kMemoryAllocationStep.
+  policy.bytes_limit =
+      (policy.bytes_limit / kMemoryAllocationStep + 1) * kMemoryAllocationStep;
+  policy.num_resources_limit = g_num_gralloc_limit;
+  SetMemoryPolicy(policy);
+
+  gl_surface_->SetBackingFrameBufferObject(
+      state_restore.framebuffer_binding_ext());
+
+  gfx::Transform transform;
+  transform.matrix().setColMajorf(draw_info->transform);
+  transform.Translate(input.scroll.x(), input.scroll.y());
+  gfx::Rect clip_rect(draw_info->clip_left,
+                      draw_info->clip_top,
+                      draw_info->clip_right - draw_info->clip_left,
+                      draw_info->clip_bottom - draw_info->clip_top);
+
+  gfx::Rect viewport_rect;
+  if (draw_info->is_layer) {
+    viewport_rect = clip_rect;
+  } else {
+    viewport_rect = input.global_visible_rect;
+    clip_rect.Intersect(viewport_rect);
+  }
+  result.clip_contains_visible_rect = clip_rect.Contains(viewport_rect);
+
+  result.did_draw =
+      compositor_->DemandDrawHw(gfx::Size(draw_info->width, draw_info->height),
+                                transform,
+                                viewport_rect,
+                                clip_rect,
+                                state_restore.stencil_enabled());
+  gl_surface_->ResetBackingFrameBufferObject();
+
+  return result;
 }
 
-// Called from different threads!
-void DeferredGpuCommandService::ScheduleTask(const base::Closure& task) {
-  {
-    base::AutoLock lock(tasks_lock_);
-    tasks_.push(task);
-  }
-  if (ScopedAllowGL::IsAllowed()) {
-    RunTasks();
-  } else {
-    RequestProcessGLOnUIThread();
-  }
-}
-
-void DeferredGpuCommandService::ScheduleIdleWork(
-    const base::Closure& callback) {
-  // TODO(sievers): Should this do anything?
-}
-
-bool DeferredGpuCommandService::UseVirtualizedGLContexts() { return true; }
-
-void DeferredGpuCommandService::RunTasks() {
-  bool has_more_tasks;
-  {
-    base::AutoLock lock(tasks_lock_);
-    has_more_tasks = tasks_.size() > 0;
-  }
-
-  while (has_more_tasks) {
-    base::Closure task;
-    {
-      base::AutoLock lock(tasks_lock_);
-      task = tasks_.front();
-      tasks_.pop();
-    }
-    task.Run();
-    {
-      base::AutoLock lock(tasks_lock_);
-      has_more_tasks = tasks_.size() > 0;
-    }
-
-  }
-}
-
-base::LazyInstance<scoped_refptr<DeferredGpuCommandService> > g_service =
-    LAZY_INSTANCE_INITIALIZER;
-
-}  // namespace
-
-InProcessViewRenderer::InProcessViewRenderer(
-    BrowserViewRenderer::Client* client,
-    content::WebContents* web_contents)
-    : client_(client),
-      web_contents_(web_contents),
-      compositor_(NULL),
-      is_paused_(false),
-      view_visible_(false),
-      window_visible_(false),
-      attached_to_window_(false),
-      dip_scale_(0.0),
-      page_scale_factor_(1.0),
-      on_new_picture_enable_(false),
-      clear_view_(false),
-      compositor_needs_continuous_invalidate_(false),
-      block_invalidates_(false),
-      width_(0),
-      height_(0),
-      hardware_initialized_(false),
-      hardware_failed_(false),
-      last_egl_context_(NULL),
-      manager_key_(g_view_renderer_manager.Get().NullKey()) {
-  CHECK(web_contents_);
-  web_contents_->SetUserData(kUserDataKey, new UserData(this));
-  content::SynchronousCompositor::SetClientForWebContents(web_contents_, this);
-
-  // Currently the logic in this class relies on |compositor_| remaining NULL
-  // until the DidInitializeCompositor() call, hence it is not set here.
-}
-
-InProcessViewRenderer::~InProcessViewRenderer() {
-  CHECK(web_contents_);
-  content::SynchronousCompositor::SetClientForWebContents(web_contents_, NULL);
-  web_contents_->SetUserData(kUserDataKey, NULL);
-  NoLongerExpectsDrawGL();
-  DCHECK(web_contents_ == NULL);  // WebContentsGone should have been called.
-}
-
-void InProcessViewRenderer::NoLongerExpectsDrawGL() {
-  GLViewRendererManager& mru = g_view_renderer_manager.Get();
-  if (manager_key_ != mru.NullKey()) {
-    mru.NoLongerExpectsDrawGL(manager_key_);
-    manager_key_ = mru.NullKey();
-  }
-}
-
-// static
-InProcessViewRenderer* InProcessViewRenderer::FromWebContents(
-    content::WebContents* contents) {
-  return UserData::GetInstance(contents);
-}
-
-void InProcessViewRenderer::WebContentsGone() {
-  web_contents_ = NULL;
-  compositor_ = NULL;
-}
-
-// static
-void InProcessViewRenderer::CalculateTileMemoryPolicy() {
-  CommandLine* cl = CommandLine::ForCurrentProcess();
-  if (cl->HasSwitch(switches::kTileMemoryMultiplier)) {
-    std::string string_value =
-        cl->GetSwitchValueASCII(switches::kTileMemoryMultiplier);
-    int int_value = 0;
-    if (base::StringToInt(string_value, &int_value) &&
-        int_value >= 2 && int_value <= 50) {
-      g_memory_multiplier = int_value;
-    }
-  }
-
-  if (cl->HasSwitch(switches::kNumGrallocBuffersPerWebview)) {
-    std::string string_value =
-        cl->GetSwitchValueASCII(switches::kNumGrallocBuffersPerWebview);
-    int int_value = 0;
-    if (base::StringToInt(string_value, &int_value) &&
-        int_value >= 50 && int_value <= 500) {
-      g_num_gralloc_limit = int_value;
-    }
-  }
-
-  const char kDefaultTileSize[] = "384";
-  if (!cl->HasSwitch(switches::kDefaultTileWidth))
-    cl->AppendSwitchASCII(switches::kDefaultTileWidth, kDefaultTileSize);
-
-  if (!cl->HasSwitch(switches::kDefaultTileHeight))
-    cl->AppendSwitchASCII(switches::kDefaultTileHeight, kDefaultTileSize);
-}
-
-bool InProcessViewRenderer::RequestProcessGL() {
-  return client_->RequestDrawGL(NULL);
-}
-
-void InProcessViewRenderer::TrimMemory(int level) {
+bool HardwareRenderer::TrimMemory(int level, bool visible) {
   // Constants from Android ComponentCallbacks2.
   enum {
     TRIM_MEMORY_RUNNING_LOW = 10,
     TRIM_MEMORY_UI_HIDDEN = 20,
     TRIM_MEMORY_BACKGROUND = 40,
   };
 
   // Not urgent enough. TRIM_MEMORY_UI_HIDDEN is treated specially because
   // it does not indicate memory pressure, but merely that the app is
   // backgrounded.
   if (level < TRIM_MEMORY_RUNNING_LOW || level == TRIM_MEMORY_UI_HIDDEN)
-    return;
-
-  // Nothing to drop.
-  if (!attached_to_window_ || !hardware_initialized_ || !compositor_)
-    return;
+    return false;
 
   // Do not release resources on view we expect to get DrawGL soon.
-  if (level < TRIM_MEMORY_BACKGROUND) {
-    client_->UpdateGlobalVisibleRect();
-    if (view_visible_ && window_visible_ &&
-        !cached_global_visible_rect_.IsEmpty()) {
-      return;
-    }
-  }
+  if (level < TRIM_MEMORY_BACKGROUND && visible)
+    return false;
 
   if (!eglGetCurrentContext()) {
     NOTREACHED();
-    return;
+    return false;
   }
 
+  DCHECK_EQ(last_egl_context_, eglGetCurrentContext());
+
   // Just set the memory limit to 0 and drop all tiles. This will be reset to
   // normal levels in the next DrawGL call.
   content::SynchronousCompositorMemoryPolicy policy;
   policy.bytes_limit = 0;
   policy.num_resources_limit = 0;
   if (memory_policy_ == policy)
-    return;
+    return false;
 
-  TRACE_EVENT0("android_webview", "InProcessViewRenderer::TrimMemory");
+  TRACE_EVENT0("android_webview", "BrowserViewRenderer::TrimMemory");
   ScopedAppGLStateRestore state_restore(
       ScopedAppGLStateRestore::MODE_RESOURCE_MANAGEMENT);
-  g_service.Get()->RunTasks();
-  ScopedAllowGL allow_gl;
+  internal::ScopedAllowGL allow_gl;
 
   SetMemoryPolicy(policy);
-  ForceFakeCompositeSW();
+  return true;
 }
 
-void InProcessViewRenderer::SetMemoryPolicy(
+void HardwareRenderer::SetMemoryPolicy(
     content::SynchronousCompositorMemoryPolicy& new_policy) {
   if (memory_policy_ == new_policy)
     return;
 
   memory_policy_ = new_policy;
   compositor_->SetMemoryPolicy(memory_policy_);
 }
 
-void InProcessViewRenderer::UpdateCachedGlobalVisibleRect() {
-  client_->UpdateGlobalVisibleRect();
+// static
+void HardwareRenderer::CalculateTileMemoryPolicy() {
+  CommandLine* cl = CommandLine::ForCurrentProcess();
+  if (cl->HasSwitch(switches::kTileMemoryMultiplier)) {
+    std::string string_value =
+        cl->GetSwitchValueASCII(switches::kTileMemoryMultiplier);
+    int int_value = 0;
+    if (base::StringToInt(string_value, &int_value) && int_value >= 2 &&
+        int_value <= 50) {
+      g_memory_multiplier = int_value;
+    }
+  }
+
+  if (cl->HasSwitch(switches::kNumGrallocBuffersPerWebview)) {
+    std::string string_value =
+        cl->GetSwitchValueASCII(switches::kNumGrallocBuffersPerWebview);
+    int int_value = 0;
+    if (base::StringToInt(string_value, &int_value) && int_value >= 50 &&
+        int_value <= 500) {

[benm (inactive), 2014/02/25 12:48:01]

nit:consider making the magic numbers consts? here and above

[boliu, 2014/02/25 19:02:22]

Screw this. Even I'm not using these anymore. Removed these two switches.

+      g_num_gralloc_limit = int_value;
+    }
+  }
+
+  const char kDefaultTileSize[] = "384";
+  if (!cl->HasSwitch(switches::kDefaultTileWidth))
+    cl->AppendSwitchASCII(switches::kDefaultTileWidth, kDefaultTileSize);
+
+  if (!cl->HasSwitch(switches::kDefaultTileHeight))
+    cl->AppendSwitchASCII(switches::kDefaultTileHeight, kDefaultTileSize);
 }
 
-bool InProcessViewRenderer::OnDraw(jobject java_canvas,
-                                   bool is_hardware_canvas,
-                                   const gfx::Vector2d& scroll,
-                                   const gfx::Rect& clip) {
-  scroll_at_start_of_frame_  = scroll;
-  if (clear_view_)
-    return false;
-  if (is_hardware_canvas && attached_to_window_ && HardwareEnabled()) {
-    // We should be performing a hardware draw here. If we don't have the
-    // comositor yet or if RequestDrawGL fails, it means we failed this draw and
-    // thus return false here to clear to background color for this draw.
-    return compositor_ && client_->RequestDrawGL(java_canvas);
-  }
-  // Perform a software draw
-  return DrawSWInternal(java_canvas, clip);
+namespace internal {
+
+bool ScopedAllowGL::allow_gl = false;
+
+// static
+bool ScopedAllowGL::IsAllowed() {
+  return GLViewRendererManager::GetInstance()->OnRenderThread() && allow_gl;
 }
 
-bool InProcessViewRenderer::InitializeHwDraw() {
-  TRACE_EVENT0("android_webview", "InitializeHwDraw");
-  DCHECK(!gl_surface_);
-  gl_surface_ = new AwGLSurface;
-  if (!g_service.Get()) {
-    g_service.Get() = new DeferredGpuCommandService;
-    content::SynchronousCompositor::SetGpuService(g_service.Get());
-  }
-  hardware_failed_ = !compositor_->InitializeHwDraw(gl_surface_);
-  hardware_initialized_ = true;
+ScopedAllowGL::ScopedAllowGL() {
+  DCHECK(GLViewRendererManager::GetInstance()->OnRenderThread());
+  DCHECK(!allow_gl);
+  allow_gl = true;
 
-  if (hardware_failed_)
-    gl_surface_ = NULL;
-
-  return !hardware_failed_;
+  if (g_service.Get())
+    g_service.Get()->RunTasks();
 }
 
-void InProcessViewRenderer::DrawGL(AwDrawGLInfo* draw_info) {
-  TRACE_EVENT0("android_webview", "InProcessViewRenderer::DrawGL");
+ScopedAllowGL::~ScopedAllowGL() { allow_gl = false; }
 
-  manager_key_ = g_view_renderer_manager.Get().DidDrawGL(manager_key_, this);
+DeferredGpuCommandService::DeferredGpuCommandService() {}
 
-  // We need to watch if the current Android context has changed and enforce
-  // a clean-up in the compositor.
-  EGLContext current_context = eglGetCurrentContext();
-  if (!current_context) {
-    TRACE_EVENT_INSTANT0(
-        "android_webview", "EarlyOut_NullEGLContext", TRACE_EVENT_SCOPE_THREAD);
+DeferredGpuCommandService::~DeferredGpuCommandService() {
+  base::AutoLock lock(tasks_lock_);
+  DCHECK(tasks_.empty());
+}
+
+// static
+void DeferredGpuCommandService::RequestProcessGLOnUIThread() {
+  if (!BrowserThread::CurrentlyOn(BrowserThread::UI)) {
+    BrowserThread::PostTask(
+        BrowserThread::UI, FROM_HERE, base::Bind(&RequestProcessGLOnUIThread));
     return;
   }

[sgurun-gerrit only, 2014/02/25 06:56:36]

slightly confusing. It is probably better to have a RequestProcess function
which would call RequestProcessGLOnUiThread rather then recurse.

 
-  ScopedAppGLStateRestore state_restore(ScopedAppGLStateRestore::MODE_DRAW);
-  if (g_service.Get())
-    g_service.Get()->RunTasks();
-  ScopedAllowGL allow_gl;
-
-  if (!attached_to_window_) {
-    TRACE_EVENT_INSTANT0(
-        "android_webview", "EarlyOut_NotAttached", TRACE_EVENT_SCOPE_THREAD);
-    return;
-  }
-
-  if (draw_info->mode == AwDrawGLInfo::kModeProcess) {
-    TRACE_EVENT_INSTANT0(
-        "android_webview", "EarlyOut_ModeProcess", TRACE_EVENT_SCOPE_THREAD);
-    return;
-  }
-
-  if (compositor_ && !hardware_initialized_) {
-    if (InitializeHwDraw()) {
-      last_egl_context_ = current_context;
-    } else {
-      TRACE_EVENT_INSTANT0(
-          "android_webview", "EarlyOut_HwInitFail", TRACE_EVENT_SCOPE_THREAD);
-      LOG(ERROR) << "WebView hardware initialization failed";
-      return;
-    }
-  }
-
-  UpdateCachedGlobalVisibleRect();
-  if (cached_global_visible_rect_.IsEmpty()) {
-    TRACE_EVENT_INSTANT0("android_webview",
-                         "EarlyOut_EmptyVisibleRect",
-                         TRACE_EVENT_SCOPE_THREAD);
-    return;
-  }
-
-  if (last_egl_context_ != current_context) {
-    // TODO(boliu): Handle context lost
-    TRACE_EVENT_INSTANT0(
-        "android_webview", "EGLContextChanged", TRACE_EVENT_SCOPE_THREAD);
-  }
-
-  if (!compositor_) {
-    TRACE_EVENT_INSTANT0(
-        "android_webview", "EarlyOut_NoCompositor", TRACE_EVENT_SCOPE_THREAD);
-    return;
-  }
-
-  // DrawGL may be called without OnDraw, so cancel |fallback_tick_| here as
-  // well just to be safe.
-  fallback_tick_.Cancel();
-
-  // Update memory budget. This will no-op in compositor if the policy has not
-  // changed since last draw.
-  content::SynchronousCompositorMemoryPolicy policy;
-  policy.bytes_limit = g_memory_multiplier * kBytesPerPixel *
-                       cached_global_visible_rect_.width() *
-                       cached_global_visible_rect_.height();
-  // Round up to a multiple of kMemoryAllocationStep.
-  policy.bytes_limit =
-      (policy.bytes_limit / kMemoryAllocationStep + 1) * kMemoryAllocationStep;
-  policy.num_resources_limit = g_num_gralloc_limit;
-  SetMemoryPolicy(policy);
-
-  DCHECK(gl_surface_);
-  gl_surface_->SetBackingFrameBufferObject(
-      state_restore.framebuffer_binding_ext());
-
-  gfx::Transform transform;
-  transform.matrix().setColMajorf(draw_info->transform);
-  transform.Translate(scroll_at_start_of_frame_.x(),
-                      scroll_at_start_of_frame_.y());
-  gfx::Rect clip_rect(draw_info->clip_left,
-                      draw_info->clip_top,
-                      draw_info->clip_right - draw_info->clip_left,
-                      draw_info->clip_bottom - draw_info->clip_top);
-
-  // Assume we always draw the full visible rect if we are drawing into a layer.
-  bool drew_full_visible_rect = true;
-
-  gfx::Rect viewport_rect;
-  if (!draw_info->is_layer) {
-    viewport_rect = cached_global_visible_rect_;
-    clip_rect.Intersect(viewport_rect);
-    drew_full_visible_rect = clip_rect.Contains(viewport_rect);
-  } else {
-    viewport_rect = clip_rect;
-  }
-
-  block_invalidates_ = true;
-  // TODO(joth): Check return value.
-  compositor_->DemandDrawHw(gfx::Size(draw_info->width, draw_info->height),
-                            transform,
-                            viewport_rect,
-                            clip_rect,
-                            state_restore.stencil_enabled());
-  block_invalidates_ = false;
-  gl_surface_->ResetBackingFrameBufferObject();
-
-  EnsureContinuousInvalidation(draw_info, !drew_full_visible_rect);
-}
-
-void InProcessViewRenderer::SetGlobalVisibleRect(
-    const gfx::Rect& visible_rect) {
-  cached_global_visible_rect_ = visible_rect;
-}
-
-bool InProcessViewRenderer::DrawSWInternal(jobject java_canvas,
-                                           const gfx::Rect& clip) {
-  if (clip.IsEmpty()) {
-    TRACE_EVENT_INSTANT0(
-        "android_webview", "EarlyOut_EmptyClip", TRACE_EVENT_SCOPE_THREAD);
-    return true;
-  }
-
-  if (!compositor_) {
-    TRACE_EVENT_INSTANT0(
-        "android_webview", "EarlyOut_NoCompositor", TRACE_EVENT_SCOPE_THREAD);
-    return false;
-  }
-
-  return JavaHelper::GetInstance()->RenderViaAuxilaryBitmapIfNeeded(
-      java_canvas,
-      scroll_at_start_of_frame_,
-      clip,
-      base::Bind(&InProcessViewRenderer::CompositeSW, base::Unretained(this)));
-}
-
-skia::RefPtr<SkPicture> InProcessViewRenderer::CapturePicture(int width,
-                                                              int height) {
-  TRACE_EVENT0("android_webview", "InProcessViewRenderer::CapturePicture");
-
-  // Return empty Picture objects for empty SkPictures.
-  skia::RefPtr<SkPicture> picture = skia::AdoptRef(new SkPicture);
-  if (width <= 0 || height <= 0) {
-    return picture;
-  }
-
-  // Reset scroll back to the origin, will go back to the old
-  // value when scroll_reset is out of scope.
-  base::AutoReset<gfx::Vector2dF> scroll_reset(&scroll_offset_dip_,
-                                               gfx::Vector2d());
-
-  SkCanvas* rec_canvas = picture->beginRecording(width, height, 0);
-  if (compositor_)
-    CompositeSW(rec_canvas);
-  picture->endRecording();
-  return picture;
-}
-
-void InProcessViewRenderer::EnableOnNewPicture(bool enabled) {
-  on_new_picture_enable_ = enabled;
-  EnsureContinuousInvalidation(NULL, false);
-}
-
-void InProcessViewRenderer::ClearView() {
-  TRACE_EVENT_INSTANT0("android_webview",
-                       "InProcessViewRenderer::ClearView",
-                       TRACE_EVENT_SCOPE_THREAD);
-  if (clear_view_)
-    return;
-
-  clear_view_ = true;
-  // Always invalidate ignoring the compositor to actually clear the webview.
-  EnsureContinuousInvalidation(NULL, true);
-}
-
-void InProcessViewRenderer::SetIsPaused(bool paused) {
-  TRACE_EVENT_INSTANT1("android_webview",
-                       "InProcessViewRenderer::SetIsPaused",
-                       TRACE_EVENT_SCOPE_THREAD,
-                       "paused",
-                       paused);
-  is_paused_ = paused;
-  EnsureContinuousInvalidation(NULL, false);
-}
-
-void InProcessViewRenderer::SetViewVisibility(bool view_visible) {
-  TRACE_EVENT_INSTANT1("android_webview",
-                       "InProcessViewRenderer::SetViewVisibility",
-                       TRACE_EVENT_SCOPE_THREAD,
-                       "view_visible",
-                       view_visible);
-  view_visible_ = view_visible;
-}
-
-void InProcessViewRenderer::SetWindowVisibility(bool window_visible) {
-  TRACE_EVENT_INSTANT1("android_webview",
-                       "InProcessViewRenderer::SetWindowVisibility",
-                       TRACE_EVENT_SCOPE_THREAD,
-                       "window_visible",
-                       window_visible);
-  window_visible_ = window_visible;
-  EnsureContinuousInvalidation(NULL, false);
-}
-
-void InProcessViewRenderer::OnSizeChanged(int width, int height) {
-  TRACE_EVENT_INSTANT2("android_webview",
-                       "InProcessViewRenderer::OnSizeChanged",
-                       TRACE_EVENT_SCOPE_THREAD,
-                       "width",
-                       width,
-                       "height",
-                       height);
-  width_ = width;
-  height_ = height;
-}
-
-void InProcessViewRenderer::OnAttachedToWindow(int width, int height) {
-  TRACE_EVENT2("android_webview",
-               "InProcessViewRenderer::OnAttachedToWindow",
-               "width",
-               width,
-               "height",
-               height);
-  attached_to_window_ = true;
-  width_ = width;
-  height_ = height;
-}
-
-void InProcessViewRenderer::OnDetachedFromWindow() {
-  TRACE_EVENT0("android_webview",
-               "InProcessViewRenderer::OnDetachedFromWindow");
-
-  NoLongerExpectsDrawGL();
-  if (hardware_initialized_) {
-    DCHECK(compositor_);
-
-    ScopedAppGLStateRestore state_restore(
-        ScopedAppGLStateRestore::MODE_RESOURCE_MANAGEMENT);
-    g_service.Get()->RunTasks();
-    ScopedAllowGL allow_gl;
-    compositor_->ReleaseHwDraw();
-    hardware_initialized_ = false;
-  }
-
-  gl_surface_ = NULL;
-  attached_to_window_ = false;
-}
-
-bool InProcessViewRenderer::IsAttachedToWindow() {
-  return attached_to_window_;
-}
-
-bool InProcessViewRenderer::IsVisible() {
-  // Ignore |window_visible_| if |attached_to_window_| is false.
-  return view_visible_ && (!attached_to_window_ || window_visible_);
-}
-
-gfx::Rect InProcessViewRenderer::GetScreenRect() {
-  return gfx::Rect(client_->GetLocationOnScreen(), gfx::Size(width_, height_));
-}
-
-void InProcessViewRenderer::DidInitializeCompositor(
-    content::SynchronousCompositor* compositor) {
-  TRACE_EVENT0("android_webview",
-               "InProcessViewRenderer::DidInitializeCompositor");
-  DCHECK(compositor && compositor_ == NULL);
-  compositor_ = compositor;
-  hardware_initialized_ = false;
-  hardware_failed_ = false;
-}
-
-void InProcessViewRenderer::DidDestroyCompositor(
-    content::SynchronousCompositor* compositor) {
-  TRACE_EVENT0("android_webview",
-               "InProcessViewRenderer::DidDestroyCompositor");
-  DCHECK(compositor_ == compositor);
-
-  // This can fail if Apps call destroy while the webview is still attached
-  // to the view tree. This is an illegal operation that will lead to leaks.
-  // Log for now. Consider a proper fix if this becomes a problem.
-  LOG_IF(ERROR, hardware_initialized_)
-      << "Destroy called before OnDetachedFromWindow. May Leak GL resources";
-  compositor_ = NULL;
-}
-
-void InProcessViewRenderer::SetContinuousInvalidate(bool invalidate) {
-  if (compositor_needs_continuous_invalidate_ == invalidate)
-    return;
-
-  TRACE_EVENT_INSTANT1("android_webview",
-                       "InProcessViewRenderer::SetContinuousInvalidate",
-                       TRACE_EVENT_SCOPE_THREAD,
-                       "invalidate",
-                       invalidate);
-  compositor_needs_continuous_invalidate_ = invalidate;
-  EnsureContinuousInvalidation(NULL, false);
-}
-
-void InProcessViewRenderer::SetDipScale(float dip_scale) {
-  dip_scale_ = dip_scale;
-  CHECK(dip_scale_ > 0);
-}
-
-gfx::Vector2d InProcessViewRenderer::max_scroll_offset() const {
-  DCHECK_GT(dip_scale_, 0);
-  return gfx::ToCeiledVector2d(gfx::ScaleVector2d(
-      max_scroll_offset_dip_, dip_scale_ * page_scale_factor_));
-}
-
-void InProcessViewRenderer::ScrollTo(gfx::Vector2d scroll_offset) {
-  gfx::Vector2d max_offset = max_scroll_offset();
-  gfx::Vector2dF scroll_offset_dip;
-  // To preserve the invariant that scrolling to the maximum physical pixel
-  // value also scrolls to the maximum dip pixel value we transform the physical
-  // offset into the dip offset by using a proportion (instead of dividing by
-  // dip_scale * page_scale_factor).
-  if (max_offset.x()) {
-    scroll_offset_dip.set_x((scroll_offset.x() * max_scroll_offset_dip_.x()) /
-                            max_offset.x());
-  }
-  if (max_offset.y()) {
-    scroll_offset_dip.set_y((scroll_offset.y() * max_scroll_offset_dip_.y()) /
-                            max_offset.y());
-  }
-
-  DCHECK_LE(0, scroll_offset_dip.x());
-  DCHECK_LE(0, scroll_offset_dip.y());
-  DCHECK_LE(scroll_offset_dip.x(), max_scroll_offset_dip_.x());
-  DCHECK_LE(scroll_offset_dip.y(), max_scroll_offset_dip_.y());
-
-  if (scroll_offset_dip_ == scroll_offset_dip)
-    return;
-
-  scroll_offset_dip_ = scroll_offset_dip;
-
-  if (compositor_)
-    compositor_->DidChangeRootLayerScrollOffset();
-}
-
-void InProcessViewRenderer::DidUpdateContent() {
-  TRACE_EVENT_INSTANT0("android_webview",
-                       "InProcessViewRenderer::DidUpdateContent",
-                       TRACE_EVENT_SCOPE_THREAD);
-  clear_view_ = false;
-  EnsureContinuousInvalidation(NULL, false);
-  if (on_new_picture_enable_)
-    client_->OnNewPicture();
-}
-
-void InProcessViewRenderer::SetMaxRootLayerScrollOffset(
-    gfx::Vector2dF new_value_dip) {
-  DCHECK_GT(dip_scale_, 0);
-
-  max_scroll_offset_dip_ = new_value_dip;
-  DCHECK_LE(0, max_scroll_offset_dip_.x());
-  DCHECK_LE(0, max_scroll_offset_dip_.y());
-
-  client_->SetMaxContainerViewScrollOffset(max_scroll_offset());
-}
-
-void InProcessViewRenderer::SetTotalRootLayerScrollOffset(
-    gfx::Vector2dF scroll_offset_dip) {
-  // TOOD(mkosiba): Add a DCHECK to say that this does _not_ get called during
-  // DrawGl when http://crbug.com/249972 is fixed.
-  if (scroll_offset_dip_ == scroll_offset_dip)
-    return;
-
-  scroll_offset_dip_ = scroll_offset_dip;
-
-  gfx::Vector2d max_offset = max_scroll_offset();
-  gfx::Vector2d scroll_offset;
-  // For an explanation as to why this is done this way see the comment in
-  // InProcessViewRenderer::ScrollTo.
-  if (max_scroll_offset_dip_.x()) {
-    scroll_offset.set_x((scroll_offset_dip.x() * max_offset.x()) /
-                        max_scroll_offset_dip_.x());
-  }
-
-  if (max_scroll_offset_dip_.y()) {
-    scroll_offset.set_y((scroll_offset_dip.y() * max_offset.y()) /
-                        max_scroll_offset_dip_.y());
-  }
-
-  DCHECK(0 <= scroll_offset.x());
-  DCHECK(0 <= scroll_offset.y());
-  // Disabled because the conditions are being violated while running
-  // AwZoomTest.testMagnification, see http://crbug.com/340648
-  // DCHECK(scroll_offset.x() <= max_offset.x());
-  // DCHECK(scroll_offset.y() <= max_offset.y());
-
-  client_->ScrollContainerViewTo(scroll_offset);
-}
-
-gfx::Vector2dF InProcessViewRenderer::GetTotalRootLayerScrollOffset() {
-  return scroll_offset_dip_;
-}
-
-bool InProcessViewRenderer::IsExternalFlingActive() const {
-  return client_->IsFlingActive();
-}
-
-void InProcessViewRenderer::SetRootLayerPageScaleFactorAndLimits(
-    float page_scale_factor,
-    float min_page_scale_factor,
-    float max_page_scale_factor) {
-  page_scale_factor_ = page_scale_factor;
-  DCHECK_GT(page_scale_factor_, 0);
-  client_->SetPageScaleFactorAndLimits(
-      page_scale_factor, min_page_scale_factor, max_page_scale_factor);
-}
-
-void InProcessViewRenderer::SetRootLayerScrollableSize(
-    gfx::SizeF scrollable_size) {
-  client_->SetContentsSize(scrollable_size);
-}
-
-void InProcessViewRenderer::DidOverscroll(
-    gfx::Vector2dF accumulated_overscroll,
-    gfx::Vector2dF latest_overscroll_delta,
-    gfx::Vector2dF current_fling_velocity) {
-  const float physical_pixel_scale = dip_scale_ * page_scale_factor_;
-  if (accumulated_overscroll == latest_overscroll_delta)
-    overscroll_rounding_error_ = gfx::Vector2dF();
-  gfx::Vector2dF scaled_overscroll_delta =
-      gfx::ScaleVector2d(latest_overscroll_delta, physical_pixel_scale);
-  gfx::Vector2d rounded_overscroll_delta = gfx::ToRoundedVector2d(
-      scaled_overscroll_delta + overscroll_rounding_error_);
-  overscroll_rounding_error_ =
-      scaled_overscroll_delta - rounded_overscroll_delta;
-  client_->DidOverscroll(rounded_overscroll_delta);
-}
-
-void InProcessViewRenderer::EnsureContinuousInvalidation(
-    AwDrawGLInfo* draw_info,
-    bool invalidate_ignore_compositor) {
-  // This method should be called again when any of these conditions change.
-  bool need_invalidate =
-      compositor_needs_continuous_invalidate_ || invalidate_ignore_compositor;
-  if (!need_invalidate || block_invalidates_)
-    return;
-
-  // Always call view invalidate. We rely the Android framework to ignore the
-  // invalidate when it's not needed such as when view is not visible.
-  if (draw_info) {
-    draw_info->dirty_left = cached_global_visible_rect_.x();
-    draw_info->dirty_top = cached_global_visible_rect_.y();
-    draw_info->dirty_right = cached_global_visible_rect_.right();
-    draw_info->dirty_bottom = cached_global_visible_rect_.bottom();
-    draw_info->status_mask |= AwDrawGLInfo::kStatusMaskDraw;
-  } else {
-    client_->PostInvalidate();
-  }
-
-  // Stop fallback ticks when one of these is true.
-  // 1) Webview is paused. Also need to check we are not in clear view since
-  // paused, offscreen still expect clear view to recover.
-  // 2) If we are attached to window and the window is not visible (eg when
-  // app is in the background). We are sure in this case the webview is used
-  // "on-screen" but that updates are not needed when in the background.
-  bool throttle_fallback_tick =
-      (is_paused_ && !clear_view_) || (attached_to_window_ && !window_visible_);
-  if (throttle_fallback_tick)
-    return;
-
-  block_invalidates_ = compositor_needs_continuous_invalidate_;
-
-  // Unretained here is safe because the callback is cancelled when
-  // |fallback_tick_| is destroyed.
-  fallback_tick_.Reset(base::Bind(&InProcessViewRenderer::FallbackTickFired,
-                                  base::Unretained(this)));
-
-  // No need to reschedule fallback tick if compositor does not need to be
-  // ticked. This can happen if this is reached because
-  // invalidate_ignore_compositor is true.
-  if (compositor_needs_continuous_invalidate_) {
-    BrowserThread::PostDelayedTask(
-        BrowserThread::UI,
-        FROM_HERE,
-        fallback_tick_.callback(),
-        base::TimeDelta::FromMilliseconds(
-            kFallbackTickTimeoutInMilliseconds));
+  HardwareRenderer* renderer =
+      GLViewRendererManager::GetInstance()->GetMostRecentlyDrawn();
+  if (!renderer || !renderer->client_->RequestDrawGL(NULL)) {
+    LOG(ERROR) << "Failed to request GL process. Deadlock likely: "
+               << !!renderer;
   }
 }
 
-void InProcessViewRenderer::FallbackTickFired() {
-  TRACE_EVENT1("android_webview",
-               "InProcessViewRenderer::FallbackTickFired",
-               "compositor_needs_continuous_invalidate_",
-               compositor_needs_continuous_invalidate_);
-
-  // This should only be called if OnDraw or DrawGL did not come in time, which
-  // means block_invalidates_ must still be true.
-  DCHECK(block_invalidates_);
-  if (compositor_needs_continuous_invalidate_ && compositor_)
-    ForceFakeCompositeSW();
+// Called from different threads!
+void DeferredGpuCommandService::ScheduleTask(const base::Closure& task) {
+  {
+    base::AutoLock lock(tasks_lock_);
+    tasks_.push(task);
+  }
+  if (ScopedAllowGL::IsAllowed()) {
+    RunTasks();
+  } else {
+    RequestProcessGLOnUIThread();
+  }
 }
 
-void InProcessViewRenderer::ForceFakeCompositeSW() {
-  DCHECK(compositor_);
-  SkBitmapDevice device(SkBitmap::kARGB_8888_Config, 1, 1);
-  SkCanvas canvas(&device);
-  CompositeSW(&canvas);
+void DeferredGpuCommandService::ScheduleIdleWork(
+    const base::Closure& callback) {
+  // TODO(sievers): Should this do anything?
 }
 
-bool InProcessViewRenderer::CompositeSW(SkCanvas* canvas) {
-  DCHECK(compositor_);
+bool DeferredGpuCommandService::UseVirtualizedGLContexts() { return true; }
 
-  fallback_tick_.Cancel();
-  block_invalidates_ = true;
-  bool result = compositor_->DemandDrawSw(canvas);
-  block_invalidates_ = false;
-  EnsureContinuousInvalidation(NULL, false);
-  return result;
+void DeferredGpuCommandService::RunTasks() {
+  bool has_more_tasks;
+  {
+    base::AutoLock lock(tasks_lock_);
+    has_more_tasks = tasks_.size() > 0;
+  }
+
+  while (has_more_tasks) {
+    base::Closure task;
+    {
+      base::AutoLock lock(tasks_lock_);
+      task = tasks_.front();
+      tasks_.pop();
+    }
+    task.Run();
+    {
+      base::AutoLock lock(tasks_lock_);
+      has_more_tasks = tasks_.size() > 0;
+    }
+  }
 }
 
-std::string InProcessViewRenderer::ToString(AwDrawGLInfo* draw_info) const {
-  std::string str;
-  base::StringAppendF(&str, "is_paused: %d ", is_paused_);
-  base::StringAppendF(&str, "view_visible: %d ", view_visible_);
-  base::StringAppendF(&str, "window_visible: %d ", window_visible_);
-  base::StringAppendF(&str, "dip_scale: %f ", dip_scale_);
-  base::StringAppendF(&str, "page_scale_factor: %f ", page_scale_factor_);
-  base::StringAppendF(&str,
-                      "compositor_needs_continuous_invalidate: %d ",
-                      compositor_needs_continuous_invalidate_);
-  base::StringAppendF(&str, "block_invalidates: %d ", block_invalidates_);
-  base::StringAppendF(&str, "view width height: [%d %d] ", width_, height_);
-  base::StringAppendF(&str, "attached_to_window: %d ", attached_to_window_);
-  base::StringAppendF(&str, "hardware_initialized: %d ", hardware_initialized_);
-  base::StringAppendF(&str, "hardware_failed: %d ", hardware_failed_);
-  base::StringAppendF(&str,
-                      "global visible rect: %s ",
-                      cached_global_visible_rect_.ToString().c_str());
-  base::StringAppendF(&str,
-                      "scroll_at_start_of_frame: %s ",
-                      scroll_at_start_of_frame_.ToString().c_str());
-  base::StringAppendF(
-      &str, "scroll_offset_dip: %s ", scroll_offset_dip_.ToString().c_str());
-  base::StringAppendF(&str,
-                      "overscroll_rounding_error_: %s ",
-                      overscroll_rounding_error_.ToString().c_str());
-  base::StringAppendF(
-      &str, "on_new_picture_enable: %d ", on_new_picture_enable_);
-  base::StringAppendF(&str, "clear_view: %d ", clear_view_);
-  if (draw_info) {
-    base::StringAppendF(&str,
-                        "clip left top right bottom: [%d %d %d %d] ",
-                        draw_info->clip_left,
-                        draw_info->clip_top,
-                        draw_info->clip_right,
-                        draw_info->clip_bottom);
-    base::StringAppendF(&str,
-                        "surface width height: [%d %d] ",
-                        draw_info->width,
-                        draw_info->height);
-    base::StringAppendF(&str, "is_layer: %d ", draw_info->is_layer);
-  }
-  return str;
+void DeferredGpuCommandService::AddRef() const {
+  base::RefCountedThreadSafe<DeferredGpuCommandService>::AddRef();
 }
 
+void DeferredGpuCommandService::Release() const {
+  base::RefCountedThreadSafe<DeferredGpuCommandService>::Release();
+}
+
+}  // namespace internal
+
 }  // namespace android_webview