gfx/ipc/CanvasRenderThread.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 _include_gfx_ipc_CanvasRenderThread_h__
   8 #define _include_gfx_ipc_CanvasRenderThread_h__
   9
  10 #include "mozilla/AlreadyAddRefed.h"
  11 #include "mozilla/Mutex.h"
  12 #include "nsCOMPtr.h"
  13 #include "nsISupportsImpl.h"
  14 #include "nsTArray.h"
  15
  16 class nsIRunnable;
  17 class nsIThread;
  18 class nsIThreadPool;
  19
  20 namespace mozilla {
  21 class TaskQueue;
  22
  23 namespace gfx {
  24
  25 /**
  26  * This class represents the virtual thread for canvas rendering. Depending on
  27  * platform requirements and user configuration, canvas rendering may happen on
  28  * the Compositor thread, Render thread or the CanvasRender thread.
  29  */
  30 class CanvasRenderThread final {
  31   NS_INLINE_DECL_THREADSAFE_REFCOUNTING_WITH_DELETE_ON_MAIN_THREAD(
  32       CanvasRenderThread)
  33
  34  public:
  35   /// Can only be called from the main thread, expected to be called at most
  36   /// once during a process' lifetime. Must be called after the Compositor and
  37   /// Render threads are initialized.
  38   static void Start();
  39
  40   /// Can only be called from the main thread. Must be called before the
  41   /// Compositor and Render threads are shutdown.
  42   static void Shutdown();
  43
  44   /// Can be called from any thread.
  45   static bool IsInCanvasRenderThread();
  46
  47   /// Can be called from any thread.
  48   static bool IsInCanvasWorkerThread();
  49
  50   /// Can be called from any thread.
  51   static bool IsInCanvasRenderOrWorkerThread();
  52
  53   /// Can be called from any thread, may return nullptr late in shutdown.
  54   static already_AddRefed<nsIThread> GetCanvasRenderThread();
  55
  56   static already_AddRefed<TaskQueue> CreateWorkerTaskQueue();
  57
  58   static void ShutdownWorkerTaskQueue(TaskQueue* aTaskQueue);
  59
  60   static void FinishShutdownWorkerTaskQueue(TaskQueue* aTaskQueue);
  61
  62   static void Dispatch(already_AddRefed<nsIRunnable> aRunnable);
  63
  64  private:
  65   CanvasRenderThread(nsCOMPtr<nsIThread>&& aThread,
  66                      nsCOMPtr<nsIThreadPool>&& aWorkers, bool aCreatedThread);
  67   ~CanvasRenderThread();
  68
  69   Mutex mMutex;
  70
  71   nsCOMPtr<nsIThread> const mThread;
  72
  73   nsCOMPtr<nsIThreadPool> const mWorkers;
  74
  75   nsTArray<RefPtr<TaskQueue>> mPendingShutdownTaskQueues MOZ_GUARDED_BY(mMutex);
  76
  77   // True if mThread points to CanvasRender thread, false if mThread points to
  78   // Compositor/Render thread.
  79   const bool mCreatedThread;
  80 };
  81
  82 }  // namespace gfx
  83 }  // namespace mozilla
  84
  85 #endif  // _include_gfx_ipc_CanvasRenderThread_h__