content/gpu/gpu_watchdog_thread.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_GPU_GPU_WATCHDOG_THREAD_H_
   6 #define CONTENT_GPU_GPU_WATCHDOG_THREAD_H_
   7
   8 #include "base/memory/ref_counted.h"
   9 #include "base/memory/weak_ptr.h"
  10 #include "base/message_loop.h"
  11 #include "base/threading/thread.h"
  12 #include "base/time.h"
  13 #include "content/common/gpu/gpu_watchdog.h"
  14
  15 // A thread that intermitently sends tasks to a group of watched message loops
  16 // and deliberately crashes if one of them does not respond after a timeout.
  17 class GpuWatchdogThread : public base::Thread,
  18                           public GpuWatchdog,
  19                           public base::RefCountedThreadSafe<GpuWatchdogThread> {
  20  public:
  21   explicit GpuWatchdogThread(int timeout);
  22
  23   // Accessible on watched thread but only modified by watchdog thread.
  24   bool armed() const { return armed_; }
  25   void PostAcknowledge();
  26
  27   // Implement GpuWatchdog.
  28   virtual void CheckArmed() OVERRIDE;
  29
  30  protected:
  31   virtual void Init() OVERRIDE;
  32   virtual void CleanUp() OVERRIDE;
  33
  34  private:
  35   friend class base::RefCountedThreadSafe<GpuWatchdogThread>;
  36
  37   // An object of this type intercepts the reception and completion of all tasks
  38   // on the watched thread and checks whether the watchdog is armed.
  39   class GpuWatchdogTaskObserver : public MessageLoop::TaskObserver {
  40    public:
  41     explicit GpuWatchdogTaskObserver(GpuWatchdogThread* watchdog);
  42     virtual ~GpuWatchdogTaskObserver();
  43
  44     // Implements MessageLoop::TaskObserver.
  45     virtual void WillProcessTask(base::TimeTicks time_posted) OVERRIDE;
  46     virtual void DidProcessTask(base::TimeTicks time_posted) OVERRIDE;
  47
  48    private:
  49     GpuWatchdogThread* watchdog_;
  50   };
  51
  52   virtual ~GpuWatchdogThread();
  53
  54   void OnAcknowledge();
  55   void OnCheck();
  56   void DeliberatelyTerminateToRecoverFromHang();
  57
  58 #if defined(OS_WIN)
  59   base::TimeDelta GetWatchedThreadTime();
  60 #endif
  61
  62   MessageLoop* watched_message_loop_;
  63   base::TimeDelta timeout_;
  64   volatile bool armed_;
  65   GpuWatchdogTaskObserver task_observer_;
  66
  67 #if defined(OS_WIN)
  68   void* watched_thread_handle_;
  69   base::TimeDelta arm_cpu_time_;
  70 #endif
  71
  72   base::Time arm_absolute_time_;
  73
  74   base::WeakPtrFactory<GpuWatchdogThread> weak_factory_;
  75
  76   DISALLOW_COPY_AND_ASSIGN(GpuWatchdogThread);
  77 };
  78
  79 #endif  // CONTENT_GPU_GPU_WATCHDOG_THREAD_H_