js/public/HelperThreadAPI.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 /*
   8  * API for supplying an external thread pool to run internal work off the main
   9  * thread.
  10  */
  11
  12 #ifndef js_HelperThreadAPI_h
  13 #define js_HelperThreadAPI_h
  14
  15 #include <stddef.h>  // size_t
  16
  17 #include "jstypes.h"  // JS_PUBLIC_API
  18
  19 namespace JS {
  20
  21 // Argument passed to the task callback to indicate whether we're invoking it
  22 // because a new task was added by the JS engine or because we're on a helper
  23 // thread that just finished a task and there are other tasks pending.
  24 enum class DispatchReason { NewTask, FinishedTask };
  25
  26 /**
  27  * Set callback to dispatch a tasks to an external thread pool.
  28  *
  29  * When the task runs it should call JS::RunHelperThreadTask.
  30  */
  31 using HelperThreadTaskCallback = void (*)(DispatchReason reason);
  32 extern JS_PUBLIC_API void SetHelperThreadTaskCallback(
  33     HelperThreadTaskCallback callback, size_t threadCount, size_t stackSize);
  34
  35 // Function to call from external thread pool to run a helper thread task.
  36 extern JS_PUBLIC_API void RunHelperThreadTask();
  37
  38 }  // namespace JS
  39
  40 #endif  // js_HelperThreadAPI_h