Added suspend/resume detection to the GpuWatchdogThread

content/gpu/gpu_watchdog_thread.h

 // 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 CONTENT_GPU_GPU_WATCHDOG_THREAD_H_
 #define CONTENT_GPU_GPU_WATCHDOG_THREAD_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
+#include "base/power_monitor/power_observer.h"
 #include "base/threading/thread.h"
 #include "base/time/time.h"
 #include "content/common/gpu/gpu_watchdog.h"
 
 namespace content {
 
 // A thread that intermitently sends tasks to a group of watched message loops
 // and deliberately crashes if one of them does not respond after a timeout.
 class GpuWatchdogThread : public base::Thread,
                           public GpuWatchdog,
+                          public base::PowerObserver,
                           public base::RefCountedThreadSafe<GpuWatchdogThread> {
  public:
   explicit GpuWatchdogThread(int timeout);
 
   // Accessible on watched thread but only modified by watchdog thread.
   bool armed() const { return armed_; }
   void PostAcknowledge();
 
   // Implement GpuWatchdog.
   virtual void CheckArmed() OVERRIDE;
 
+  // Must be called after a PowerMonitor has been created. Can be called from
+  // any thread.
+  void AddPowerObserver();
+
  protected:
   virtual void Init() OVERRIDE;
   virtual void CleanUp() OVERRIDE;
 
  private:
   friend class base::RefCountedThreadSafe<GpuWatchdogThread>;
 
   // An object of this type intercepts the reception and completion of all tasks
   // on the watched thread and checks whether the watchdog is armed.
   class GpuWatchdogTaskObserver : public base::MessageLoop::TaskObserver {
    public:
     explicit GpuWatchdogTaskObserver(GpuWatchdogThread* watchdog);
     virtual ~GpuWatchdogTaskObserver();
 
     // Implements MessageLoop::TaskObserver.
     virtual void WillProcessTask(
         const base::PendingTask& pending_task) OVERRIDE;
     virtual void DidProcessTask(const base::PendingTask& pending_task) OVERRIDE;
 
    private:
     GpuWatchdogThread* watchdog_;
   };
 
   virtual ~GpuWatchdogThread();
 
   void OnAcknowledge();
   void OnCheck(bool after_suspend);
   void DeliberatelyTerminateToRecoverFromHang();
 
+  void OnAddPowerObserver();
+
+  // Implement PowerObserver.
+  virtual void OnSuspend() OVERRIDE;
+  virtual void OnResume() OVERRIDE;
+
 #if defined(OS_WIN)
   base::TimeDelta GetWatchedThreadTime();
 #endif
 
   base::MessageLoop* watched_message_loop_;
   base::TimeDelta timeout_;
   volatile bool armed_;
   GpuWatchdogTaskObserver task_observer_;
 
 #if defined(OS_WIN)
   void* watched_thread_handle_;
   base::TimeDelta arm_cpu_time_;
 #endif
 
   // Time after which it's assumed that the computer has been suspended since
   // the task was posted.
   base::Time suspension_timeout_;
 
   base::WeakPtrFactory<GpuWatchdogThread> weak_factory_;
 
+  bool suspended_;
+
   DISALLOW_COPY_AND_ASSIGN(GpuWatchdogThread);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_GPU_GPU_WATCHDOG_THREAD_H_