Send idle notifications to V8 after commit

content/renderer/gpu/render_widget_compositor.cc

 // Copyright (c) 2013 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 "content/renderer/gpu/render_widget_compositor.h"
 
 #include <limits>
 #include <string>
 
 #include "base/command_line.h"
@@ skipping 20 matching lines @@
 #include "content/child/child_shared_bitmap_manager.h"
 #include "content/common/content_switches_internal.h"
 #include "content/common/gpu/client/context_provider_command_buffer.h"
 #include "content/public/common/content_switches.h"
 #include "content/renderer/input/input_handler_manager.h"
 #include "content/renderer/render_thread_impl.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
 #include "third_party/WebKit/public/platform/WebCompositeAndReadbackAsyncCallback.h"
 #include "third_party/WebKit/public/platform/WebSelectionBound.h"
 #include "third_party/WebKit/public/platform/WebSize.h"
+#include "third_party/WebKit/public/web/WebKit.h"
 #include "third_party/WebKit/public/web/WebWidget.h"
 #include "ui/gfx/frame_time.h"
 #include "ui/gl/gl_switches.h"
 #include "ui/native_theme/native_theme_switches.h"
 
 #if defined(OS_ANDROID)
 #include "content/renderer/android/synchronous_compositor_factory.h"
 #include "ui/gfx/android/device_display_info.h"
 #endif
 
@@ skipping 105 matching lines @@
 
 // static
 scoped_ptr<RenderWidgetCompositor> RenderWidgetCompositor::Create(
     RenderWidget* widget,
     bool threaded) {
   scoped_ptr<RenderWidgetCompositor> compositor(
       new RenderWidgetCompositor(widget, threaded));
 
   CommandLine* cmd = CommandLine::ForCurrentProcess();
 
+  if (cmd->HasSwitch(switches::kSendV8IdleNotificationAfterCommit))
+    compositor->send_v8_idle_notification_after_commit_ = true;

[jamesr, 2014/08/25 18:06:26]

touching a private var directly is dodgy. make this a constructor parameter?

[ernstm, 2014/08/25 18:25:11]

I moved the check for the command line flag into the constructor and set the
member there. Is that okay?

+
   cc::LayerTreeSettings settings;
 
   // For web contents, layer transforms should scale up the contents of layers
   // to keep content always crisp when possible.
   settings.layer_transforms_should_scale_layer_contents = true;
 
   settings.throttle_frame_production =
       !cmd->HasSwitch(switches::kDisableGpuVsync);
   settings.begin_frame_scheduling_enabled =
       cmd->HasSwitch(switches::kEnableBeginFrameScheduling);
@@ skipping 229 matching lines @@
 
   compositor->Initialize(settings);
 
   return compositor.Pass();
 }
 
 RenderWidgetCompositor::RenderWidgetCompositor(RenderWidget* widget,
                                                bool threaded)
     : threaded_(threaded),
       suppress_schedule_composite_(false),
-      widget_(widget) {
+      widget_(widget),
+      send_v8_idle_notification_after_commit_(false) {
 }
 
 RenderWidgetCompositor::~RenderWidgetCompositor() {}
 
 const base::WeakPtr<cc::InputHandler>&
 RenderWidgetCompositor::GetInputHandler() {
   return layer_tree_host_->GetInputHandler();
 }
 
 void RenderWidgetCompositor::SetSuppressScheduleComposite(bool suppress) {
@@ skipping 325 matching lines @@
 void RenderWidgetCompositor::WillBeginMainFrame(int frame_id) {
   widget_->InstrumentWillBeginFrame(frame_id);
   widget_->willBeginCompositorFrame();
 }
 
 void RenderWidgetCompositor::DidBeginMainFrame() {
   widget_->InstrumentDidBeginFrame();
 }
 
 void RenderWidgetCompositor::BeginMainFrame(const cc::BeginFrameArgs& args) {
+  begin_main_frame_time_ = args.frame_time;
+  begin_main_frame_interval_ = args.interval;
   double frame_time = (args.frame_time - base::TimeTicks()).InSecondsF();
   WebBeginFrameArgs web_begin_frame_args = WebBeginFrameArgs(frame_time);
   widget_->webwidget()->beginFrame(web_begin_frame_args);
 }
 
 void RenderWidgetCompositor::Layout() {
   widget_->webwidget()->layout();
 }
 
 void RenderWidgetCompositor::ApplyScrollAndScale(
     const gfx::Vector2d& scroll_delta,
     float page_scale) {
   widget_->webwidget()->applyScrollAndScale(scroll_delta, page_scale);
 }
 
 scoped_ptr<cc::OutputSurface> RenderWidgetCompositor::CreateOutputSurface(
     bool fallback) {
   return widget_->CreateOutputSurface(fallback);
 }
 
 void RenderWidgetCompositor::DidInitializeOutputSurface() {
 }
 
 void RenderWidgetCompositor::WillCommit() {
   widget_->InstrumentWillComposite();
 }
 
 void RenderWidgetCompositor::DidCommit() {
+  if (send_v8_idle_notification_after_commit_) {
+    int idle_time_in_ms =
+        std::max(0L, (begin_main_frame_time_ +
+                      begin_main_frame_interval_ -
+                      gfx::FrameTime::Now()).InMilliseconds());
+    if (idle_time_in_ms)
+      blink::mainThreadIsolate()->IdleNotification(idle_time_in_ms);
+  }
+
   widget_->DidCommitCompositorFrame();
   widget_->didBecomeReadyForAdditionalInput();
 }
 
 void RenderWidgetCompositor::DidCommitAndDrawFrame() {
   widget_->didCommitAndDrawCompositorFrame();
 }
 
 void RenderWidgetCompositor::DidCompleteSwapBuffers() {
   widget_->didCompleteSwapBuffers();
@@ skipping 18 matching lines @@
   widget_->OnSwapBuffersAborted();
 }
 
 void RenderWidgetCompositor::RateLimitSharedMainThreadContext() {
   cc::ContextProvider* provider =
       RenderThreadImpl::current()->SharedMainThreadContextProvider().get();
   provider->ContextGL()->RateLimitOffscreenContextCHROMIUM();
 }
 
 }  // namespace content