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/time.h"
  13 #include "content/common/gpu/gpu_watchdog.h"
  14
  15 namespace content {
  16
  17 // A thread that intermitently sends tasks to a group of watched message loops
  18 // and deliberately crashes if one of them does not respond after a timeout.
  19 class GpuWatchdogThread : public base::Thread,
  20                           public GpuWatchdog,
  21                           public base::RefCountedThreadSafe<GpuWatchdogThread> {
  22  public:
  23   explicit GpuWatchdogThread(int timeout);
  24
  25   // Accessible on watched thread but only modified by watchdog thread.
  26   bool armed() const { return armed_; }
  27   void PostAcknowledge();
  28
  29   // Implement GpuWatchdog.
  30   virtual void CheckArmed() OVERRIDE;
  31
  32  protected:
  33   virtual void Init() OVERRIDE;
  34   virtual void CleanUp() OVERRIDE;
  35
  36  private:
  37   friend class base::RefCountedThreadSafe<GpuWatchdogThread>;
  38
  39   // An object of this type intercepts the reception and completion of all tasks
  40   // on the watched thread and checks whether the watchdog is armed.
  41   class GpuWatchdogTaskObserver : public base::MessageLoop::TaskObserver {
  42    public:
  43     explicit GpuWatchdogTaskObserver(GpuWatchdogThread* watchdog);
  44     virtual ~GpuWatchdogTaskObserver();
  45
  46     // Implements MessageLoop::TaskObserver.
  47     virtual void WillProcessTask(
  48         const base::PendingTask& pending_task) OVERRIDE;
  49     virtual void DidProcessTask(const base::PendingTask& pending_task) OVERRIDE;
  50
  51    private:
  52     GpuWatchdogThread* watchdog_;
  53   };
  54
  55   virtual ~GpuWatchdogThread();
  56
  57   void OnAcknowledge();
  58   void OnCheck(bool after_suspend);
  59   void DeliberatelyTerminateToRecoverFromHang();
  60
  61 #if defined(OS_WIN)
  62   base::TimeDelta GetWatchedThreadTime();
  63 #endif
  64
  65   base::MessageLoop* watched_message_loop_;
  66   base::TimeDelta timeout_;
  67   volatile bool armed_;
  68   GpuWatchdogTaskObserver task_observer_;
  69
  70 #if defined(OS_WIN)
  71   void* watched_thread_handle_;
  72   base::TimeDelta arm_cpu_time_;
  73 #endif
  74
  75   // Time after which it's assumed that the computer has been suspended since
  76   // the task was posted.
  77   base::Time suspension_timeout_;
  78
  79   base::WeakPtrFactory<GpuWatchdogThread> weak_factory_;
  80
  81   DISALLOW_COPY_AND_ASSIGN(GpuWatchdogThread);
  82 };
  83
  84 }  // namespace content
  85
  86 #endif  // CONTENT_GPU_GPU_WATCHDOG_THREAD_H_