xpcom/threads/nsThreadManager.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef nsThreadManager_h__
   8 #define nsThreadManager_h__
   9
  10 #include "mozilla/Mutex.h"
  11 #include "nsIThreadManager.h"
  12 #include "nsRefPtrHashtable.h"
  13 #include "nsThread.h"
  14
  15 class nsIRunnable;
  16
  17 namespace mozilla {
  18 class ReentrantMonitor;
  19 }
  20
  21 class nsThreadManager : public nsIThreadManager
  22 {
  23 public:
  24 #ifdef MOZ_NUWA_PROCESS
  25   struct ThreadStatusInfo;
  26   class AllThreadsWereIdleListener {
  27   public:
  28     NS_INLINE_DECL_REFCOUNTING(AllThreadsWereIdleListener);
  29     virtual void OnAllThreadsWereIdle() = 0;
  30   protected:
  31     virtual ~AllThreadsWereIdleListener()
  32     {
  33     }
  34   };
  35 #endif // MOZ_NUWA_PROCESS
  36
  37   NS_DECL_ISUPPORTS
  38   NS_DECL_NSITHREADMANAGER
  39
  40   static nsThreadManager* get()
  41   {
  42     static nsThreadManager sInstance;
  43     return &sInstance;
  44   }
  45
  46   nsresult Init();
  47
  48   // Shutdown all threads.  This function should only be called on the main
  49   // thread of the application process.
  50   void Shutdown();
  51
  52   // Called by nsThread to inform the ThreadManager it exists.  This method
  53   // must be called when the given thread is the current thread.
  54   void RegisterCurrentThread(nsThread* aThread);
  55
  56   // Called by nsThread to inform the ThreadManager it is going away.  This
  57   // method must be called when the given thread is the current thread.
  58   void UnregisterCurrentThread(nsThread* aThread);
  59
  60   // Returns the current thread.  Returns null if OOM or if ThreadManager isn't
  61   // initialized.
  62   nsThread* GetCurrentThread();
  63
  64   // Returns the maximal number of threads that have been in existence
  65   // simultaneously during the execution of the thread manager.
  66   uint32_t GetHighestNumberOfThreads();
  67
  68   // This needs to be public in order to support static instantiation of this
  69   // class with older compilers (e.g., egcs-2.91.66).
  70   ~nsThreadManager()
  71   {
  72   }
  73
  74 #ifdef MOZ_NUWA_PROCESS
  75   void SetIgnoreThreadStatus();
  76
  77   // |SetThreadWorking| and |SetThreadIdle| set status of thread that is
  78   // currently running. They get thread status information from TLS and pass
  79   // the information to |SetThreadIsWorking|.
  80   void SetThreadIdle(nsIRunnable** aReturnRunnable);
  81   void SetThreadWorking();
  82
  83   // |SetThreadIsWorking| is where is status actually changed. Thread status
  84   // information is passed as a argument so caller must obtain the structure
  85   // by itself. If this method is invoked on main thread, |aReturnRunnable|
  86   // should be provided to receive the runnable of notifying listeners.
  87   // |ResetIsDispatchingToMainThread| should be invoked after caller on main
  88   // thread dispatched the task to main thread's queue.
  89   void SetThreadIsWorking(ThreadStatusInfo* aInfo,
  90                           bool aIsWorking,
  91                           nsIRunnable** aReturnRunnable);
  92   void ResetIsDispatchingToMainThread();
  93
  94   void AddAllThreadsWereIdleListener(AllThreadsWereIdleListener *listener);
  95   void RemoveAllThreadsWereIdleListener(AllThreadsWereIdleListener *listener);
  96   ThreadStatusInfo* GetCurrentThreadStatusInfo();
  97 #endif // MOZ_NUWA_PROCESS
  98
  99 private:
 100   nsThreadManager()
 101     : mCurThreadIndex(0)
 102     , mMainPRThread(nullptr)
 103     , mLock("nsThreadManager.mLock")
 104     , mInitialized(false)
 105     , mCurrentNumberOfThreads(1)
 106     , mHighestNumberOfThreads(1)
 107 #ifdef MOZ_NUWA_PROCESS
 108     , mMonitor(nullptr)
 109     , mMainThreadStatusInfo(nullptr)
 110     , mDispatchingToMainThread(nullptr)
 111 #endif
 112   {
 113   }
 114
 115   nsRefPtrHashtable<nsPtrHashKey<PRThread>, nsThread> mThreadsByPRThread;
 116   unsigned            mCurThreadIndex;  // thread-local-storage index
 117   nsRefPtr<nsThread>  mMainThread;
 118   PRThread*           mMainPRThread;
 119   mozilla::OffTheBooksMutex mLock;  // protects tables
 120   mozilla::Atomic<bool> mInitialized;
 121
 122   // The current number of threads
 123   uint32_t            mCurrentNumberOfThreads;
 124   // The highest number of threads encountered so far during the session
 125   uint32_t            mHighestNumberOfThreads;
 126
 127 #ifdef MOZ_NUWA_PROCESS
 128   static void DeleteThreadStatusInfo(void *aData);
 129   unsigned mThreadStatusInfoIndex;
 130   nsTArray<nsRefPtr<AllThreadsWereIdleListener>> mThreadsIdledListeners;
 131   nsTArray<ThreadStatusInfo*> mThreadStatusInfos;
 132   mozilla::UniquePtr<mozilla::ReentrantMonitor> mMonitor;
 133   ThreadStatusInfo* mMainThreadStatusInfo;
 134   // |mDispatchingToMainThread| is set when all thread are found to be idle
 135   // before task of notifying all listeners are dispatched to main thread.
 136   // The flag is protected by |mMonitor|.
 137   bool mDispatchingToMainThread;
 138 #endif // MOZ_NUWA_PROCESS
 139 };
 140
 141 #define NS_THREADMANAGER_CID                       \
 142 { /* 7a4204c6-e45a-4c37-8ebb-6709a22c917c */       \
 143   0x7a4204c6,                                      \
 144   0xe45a,                                          \
 145   0x4c37,                                          \
 146   {0x8e, 0xbb, 0x67, 0x09, 0xa2, 0x2c, 0x91, 0x7c} \
 147 }
 148
 149 #endif  // nsThreadManager_h__