Upstream support for WebKit shared timer toggling.

This is part of Chrome for Android upstreaming.

These changes are used on the Java app side to suspend webkit timers in all
renderers when activity is paused and resume timers when activity is resumed.

This reduces javascript execution when the app is in the background, causing
lesser CPU and network usage. It doesn't stop javascript altogether because if
the page JS is constantly running without relying on timers/events then it
continues to run (but that is quite rare).


Review URL: https://chromiumcodereview.appspot.com/10690023

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@147438 0039d316-1c4b-4281-b951-d872f2087c98

base/android/jni_generator/jni_generator.py

@@ -160,6 +160,7 @@ def JavaParamToJni(param):
        'PasswordListObserver'),
       'Lorg/chromium/base/SystemMessageHandler',
       'Lorg/chromium/chrome/browser/JSModalDialog',
+      'Lorg/chromium/chrome/browser/ProcessUtils',
       'Lorg/chromium/chrome/browser/SelectFileDialog',
       'Lorg/chromium/content/browser/ContentVideoView',
       'Lorg/chromium/content/browser/ContentViewClient',

chrome/DEPS

@@ -2,6 +2,7 @@ include_rules = [
   "+ash",
   "+crypto",
   "+gpu",
+  "+jni",
   "+native_client",
   "+net",
   "+printing",

chrome/android/java/src/org/chromium/chrome/browser/ProcessUtils.java

@@ -0,0 +1,25 @@
+// Copyright (c) 2012 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.
+
+package org.chromium.chrome.browser;
+
+/**
+ * A set of utility methods related to the various Chrome processes.
+ */
+public class ProcessUtils {
+    // To prevent this class from being instantiated.
+    private ProcessUtils() {
+    }
+
+    /**
+     * Suspends Webkit timers in all renderers.
+     *
+     * @param suspend true if timers should be suspended.
+     */
+    public static void toggleWebKitSharedTimers(boolean suspend) {
+        nativeToggleWebKitSharedTimers(suspend);
+    }
+
+    private static native void nativeToggleWebKitSharedTimers(boolean suspend);
+}

chrome/browser/android/process_utils.cc

@@ -0,0 +1,60 @@
+// Copyright (c) 2012 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 "chrome/browser/android/process_utils.h"
+
+#include <vector>
+
+#include "base/lazy_instance.h"
+#include "base/logging.h"
+#include "chrome/common/render_messages.h"
+#include "content/public/browser/render_process_host.h"
+#include "jni/process_utils_jni.h"
+
+namespace {
+
+// Only accessed from the JNI thread by ToggleWebKitSharedTimers() which is
+// implemented below.
+base::LazyInstance<std::vector<int /* process id */> > g_suspended_processes =
+    LAZY_INSTANCE_INITIALIZER;
+
+// Suspends timers in all current render processes.
+void SuspendWebKitSharedTimers(std::vector<int>* suspended_processes) {
+  for (content::RenderProcessHost::iterator i(
+          content::RenderProcessHost::AllHostsIterator());
+       !i.IsAtEnd(); i.Advance()) {
+    content::RenderProcessHost* host = i.GetCurrentValue();
+    suspended_processes->push_back(host->GetID());
+    host->Send(new ChromeViewMsg_ToggleWebKitSharedTimer(true));
+  }
+}
+
+void ResumeWebkitSharedTimers(const std::vector<int>& suspended_processes) {
+  for (std::vector<int>::const_iterator it = suspended_processes.begin();
+       it != suspended_processes.end(); ++it) {
+    content::RenderProcessHost* host = content::RenderProcessHost::FromID(*it);
+    if (host)
+      host->Send(new ChromeViewMsg_ToggleWebKitSharedTimer(false));
+  }
+}
+
+}  // namespace
+
+static void ToggleWebKitSharedTimers(JNIEnv* env,
+                                     jclass obj,
+                                     jboolean suspend) {
+  std::vector<int>* suspended_processes = &g_suspended_processes.Get();
+  if (suspend) {
+    DCHECK(suspended_processes->empty());
+    SuspendWebKitSharedTimers(suspended_processes);
+  } else {
+    ResumeWebkitSharedTimers(*suspended_processes);
+    suspended_processes->clear();
+  }
+}
+
+// TODO(pliard): http://crbug.com/137674
+bool RegisterProcessUtils(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}

chrome/browser/android/process_utils.h

@@ -0,0 +1,12 @@
+// Copyright (c) 2012 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.
+
+#ifndef CHROME_BROWSER_ANDROID_PROCESS_UTILS_H_
+#define CHROME_BROWSER_ANDROID_PROCESS_UTILS_H_
+
+#include <jni.h>
+
+bool RegisterProcessUtils(JNIEnv* env);
+
+#endif  // CHROME_BROWSER_ANDROID_PROCESS_UTILS_H_

chrome/chrome_browser.gypi

@@ -106,6 +106,8 @@
         'browser/accessibility/invert_bubble_prefs.h',
         'browser/android/chrome_startup_flags.cc',
         'browser/android/chrome_startup_flags.h',
+        'browser/android/process_utils.cc',
+        'browser/android/process_utils.h',
         'browser/alternate_nav_url_fetcher.cc',
         'browser/alternate_nav_url_fetcher.h',
         'browser/app_controller_mac.h',
@@ -4856,6 +4858,9 @@
           ],
         }],
         ['OS=="android"', {
+          'dependencies': [
+            'chrome_browser_jni_headers',
+          ],
           'sources': [
             'browser/sync/glue/synced_window_delegate_registry.cc',
             'browser/sync/glue/synced_window_delegate_registry.h',
@@ -5443,4 +5448,24 @@
       'includes': [ '../build/protoc.gypi' ]
     },
   ],
+  'conditions': [
+    ['OS == "android"', {
+      'targets': [
+        {
+          'target_name': 'chrome_browser_jni_headers',
+          'type': 'none',
+          'variables': {
+            'java_sources': [
+              'android/java/src/org/chromium/chrome/browser/ProcessUtils.java',
+            ],
+            'jni_headers': [
+              '<(SHARED_INTERMEDIATE_DIR)/chrome/jni/process_utils_jni.h',
+            ],
+          },
+          'includes': [ '../build/jni_generator.gypi' ],
+        },
+      ],
+     },
+    ],
+  ],
 }

chrome/common/render_messages.h

@@ -342,6 +342,10 @@ IPC_MESSAGE_ROUTED0(ChromeViewMsg_GetFPS)
 // Tells the view it is displaying an interstitial page.
 IPC_MESSAGE_ROUTED0(ChromeViewMsg_SetAsInterstitial)
 
+// Tells the renderer to suspend/resume the webkit timers.
+IPC_MESSAGE_CONTROL1(ChromeViewMsg_ToggleWebKitSharedTimer,
+                     bool /* suspend */)
+
 //-----------------------------------------------------------------------------
 // Misc messages
 // These are messages sent from the renderer to the browser process.

chrome/renderer/chrome_render_process_observer.cc

@@ -233,6 +233,8 @@ bool ChromeRenderProcessObserver::OnControlMessageReceived(
     IPC_MESSAGE_HANDLER(ChromeViewMsg_PurgeMemory, OnPurgeMemory)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_SetContentSettingRules,
                         OnSetContentSettingRules)
+    IPC_MESSAGE_HANDLER(ChromeViewMsg_ToggleWebKitSharedTimer,
+                        OnToggleWebKitSharedTimer)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
@@ -320,6 +322,10 @@ void ChromeRenderProcessObserver::OnGetV8HeapStats() {
       heap_stats.total_heap_size(), heap_stats.used_heap_size()));
 }
 
+void ChromeRenderProcessObserver::OnToggleWebKitSharedTimer(bool suspend) {
+  RenderThread::Get()->ToggleWebKitSharedTimer(suspend);
+}
+
 void ChromeRenderProcessObserver::OnPurgeMemory() {
   RenderThread::Get()->EnsureWebKitInitialized();
 

chrome/renderer/chrome_render_process_observer.h

@@ -65,6 +65,7 @@ class ChromeRenderProcessObserver : public content::RenderProcessObserver {
   void OnWriteTcmallocHeapProfile(const FilePath::StringType& filename);
   void OnGetV8HeapStats();
   void OnPurgeMemory();
+  void OnToggleWebKitSharedTimer(bool suspend);
 
   static bool is_incognito_process_;
   scoped_ptr<content::ResourceDispatcherDelegate> resource_delegate_;

content/public/renderer/render_thread.h

@@ -104,6 +104,9 @@ class CONTENT_EXPORT RenderThread : public IPC::Sender {
   virtual void SetIdleNotificationDelayInMs(
       int64 idle_notification_delay_in_ms) = 0;
 
+  // Suspend/resume the webkit timer for this renderer.
+  virtual void ToggleWebKitSharedTimer(bool suspend) = 0;
+
   virtual void UpdateHistograms(int sequence_number) = 0;
 
 #if defined(OS_WIN)

content/public/test/mock_render_thread.h

@@ -69,11 +69,12 @@ class MockRenderThread : public RenderThread {
   virtual int64 GetIdleNotificationDelayInMs() const OVERRIDE;
   virtual void SetIdleNotificationDelayInMs(
       int64 idle_notification_delay_in_ms) OVERRIDE;
+  virtual void ToggleWebKitSharedTimer(bool suspend) OVERRIDE;
+  virtual void UpdateHistograms(int sequence_number) OVERRIDE;
 #if defined(OS_WIN)
   virtual void PreCacheFont(const LOGFONT& log_font) OVERRIDE;
   virtual void ReleaseCachedFonts() OVERRIDE;
 #endif
-  virtual void UpdateHistograms(int sequence_number) OVERRIDE;
 
   //////////////////////////////////////////////////////////////////////////
   // The following functions are called by the test itself.

content/renderer/render_thread_impl.cc

@@ -728,6 +728,21 @@ void RenderThreadImpl::SetIdleNotificationDelayInMs(
   idle_notification_delay_in_ms_ = idle_notification_delay_in_ms;
 }
 
+void RenderThreadImpl::ToggleWebKitSharedTimer(bool suspend) {
+  if (suspend_webkit_shared_timer_) {
+    EnsureWebKitInitialized();
+    if (suspend) {
+      webkit_platform_support_->SuspendSharedTimer();
+    } else {
+      webkit_platform_support_->ResumeSharedTimer();
+    }
+  }
+}
+
+void RenderThreadImpl::UpdateHistograms(int sequence_number) {
+  child_histogram_message_filter()->SendHistograms(sequence_number);
+}
+
 void RenderThreadImpl::PostponeIdleNotification() {
   idle_notifications_to_skip_ = 2;
 }
@@ -775,10 +790,6 @@ void RenderThreadImpl::ReleaseCachedFonts() {
 
 #endif  // OS_WIN
 
-void RenderThreadImpl::UpdateHistograms(int sequence_number) {
-  child_histogram_message_filter()->SendHistograms(sequence_number);
-}
-
 bool RenderThreadImpl::IsWebFrameValid(WebKit::WebFrame* web_frame) {
   if (!web_frame)
     return false; // We must be shutting down.

content/renderer/render_thread_impl.h

@@ -126,11 +126,12 @@ class CONTENT_EXPORT RenderThreadImpl : public content::RenderThread,
   virtual int64 GetIdleNotificationDelayInMs() const OVERRIDE;
   virtual void SetIdleNotificationDelayInMs(
       int64 idle_notification_delay_in_ms) OVERRIDE;
+  virtual void ToggleWebKitSharedTimer(bool suspend) OVERRIDE;
+  virtual void UpdateHistograms(int sequence_number) OVERRIDE;
 #if defined(OS_WIN)
   virtual void PreCacheFont(const LOGFONT& log_font) OVERRIDE;
   virtual void ReleaseCachedFonts() OVERRIDE;
 #endif
-  virtual void UpdateHistograms(int sequence_number) OVERRIDE;
 
   // content::ChildThread:
   virtual bool IsWebFrameValid(WebKit::WebFrame* frame) OVERRIDE;

content/test/mock_render_thread.cc

@@ -165,6 +165,12 @@ void MockRenderThread::SetIdleNotificationDelayInMs(
     int64 idle_notification_delay_in_ms) {
 }
 
+void MockRenderThread::ToggleWebKitSharedTimer(bool suspend) {
+}
+
+void MockRenderThread::UpdateHistograms(int sequence_number) {
+}
+
 #if defined(OS_WIN)
 void MockRenderThread::PreCacheFont(const LOGFONT& log_font) {
 }
@@ -174,9 +180,6 @@ void MockRenderThread::ReleaseCachedFonts() {
 
 #endif  // OS_WIN
 
-void MockRenderThread::UpdateHistograms(int sequence_number) {
-}
-
 void MockRenderThread::SendCloseMessage() {
   ViewMsg_Close msg(routing_id_);
   widget_->OnMessageReceived(msg);