| // Copyright 2017 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef BASE_TASK_SCHEDULER_SCHEDULER_SINGLE_THREAD_TASK_RUNNER_MANAGER_H_ |
| #define BASE_TASK_SCHEDULER_SCHEDULER_SINGLE_THREAD_TASK_RUNNER_MANAGER_H_ |
| |
| #include <memory> |
| #include <string> |
| #include <vector> |
| |
| #include "base/atomicops.h" |
| #include "base/base_export.h" |
| #include "base/logging.h" |
| #include "base/macros.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/task_scheduler/scheduler_lock.h" |
| #include "base/threading/platform_thread.h" |
| #include "build/build_config.h" |
| |
| namespace base { |
| |
| class TaskTraits; |
| class SingleThreadTaskRunner; |
| |
| namespace internal { |
| |
| class DelayedTaskManager; |
| class SchedulerWorker; |
| class TaskTracker; |
| |
| namespace { |
| |
| class SchedulerWorkerDelegate; |
| |
| } // namespace |
| |
| // Manages a pool of threads which are each associated with one |
| // SingleThreadTaskRunner. |
| // |
| // No threads are created (and hence no tasks can run) before Start() is called. |
| // |
| // This class is thread-safe. |
| class BASE_EXPORT SchedulerSingleThreadTaskRunnerManager final { |
| public: |
| SchedulerSingleThreadTaskRunnerManager( |
| TaskTracker* task_tracker, |
| DelayedTaskManager* delayed_task_manager); |
| ~SchedulerSingleThreadTaskRunnerManager(); |
| |
| // Starts threads for existing SingleThreadTaskRunners and allows threads to |
| // be started when SingleThreadTaskRunners are created in the future. |
| void Start(); |
| |
| // Creates a SingleThreadTaskRunner which runs tasks with |traits| on a |
| // dedicated thread named "TaskSchedulerSingleThread" + |name| + index. |
| // |priority_hint| is the preferred thread priority; the actual thread |
| // priority depends on shutdown state and platform capabilities. |
| scoped_refptr<SingleThreadTaskRunner> CreateSingleThreadTaskRunnerWithTraits( |
| const std::string& name, |
| ThreadPriority priority_hint, |
| const TaskTraits& traits); |
| |
| #if defined(OS_WIN) |
| // Creates a SingleThreadTaskRunner which runs tasks with |traits| on a |
| // dedicated COM STA thread named "TaskSchedulerSingleThreadCOMSTA" + |name| + |
| // index. |priority_hint| is the preferred thread priority; the actual thread |
| // priority depends on shutdown state and platform capabilities. |
| scoped_refptr<SingleThreadTaskRunner> CreateCOMSTATaskRunnerWithTraits( |
| const std::string& name, |
| ThreadPriority priority_hint, |
| const TaskTraits& traits); |
| #endif // defined(OS_WIN) |
| |
| void JoinForTesting(); |
| |
| private: |
| class SchedulerSingleThreadTaskRunner; |
| |
| template <typename DelegateType> |
| scoped_refptr<SingleThreadTaskRunner> |
| CreateSingleThreadTaskRunnerWithDelegate(const std::string& name, |
| ThreadPriority priority_hint, |
| const TaskTraits& traits); |
| |
| template <typename DelegateType> |
| std::unique_ptr<SchedulerWorkerDelegate> CreateSchedulerWorkerDelegate( |
| const std::string& name, |
| int id); |
| |
| template <typename DelegateType> |
| SchedulerWorker* CreateAndRegisterSchedulerWorker( |
| const std::string& name, |
| ThreadPriority priority_hint); |
| |
| void UnregisterSchedulerWorker(SchedulerWorker* worker); |
| |
| TaskTracker* const task_tracker_; |
| DelayedTaskManager* const delayed_task_manager_; |
| |
| // Synchronizes access to |workers_|, |next_worker_id_| and |started_|. |
| SchedulerLock lock_; |
| std::vector<scoped_refptr<SchedulerWorker>> workers_; |
| int next_worker_id_ = 0; |
| |
| // Set to true when Start() is called. |
| bool started_ = false; |
| |
| #if DCHECK_IS_ON() |
| subtle::Atomic32 workers_unregistered_during_join_ = 0; |
| #endif |
| |
| DISALLOW_COPY_AND_ASSIGN(SchedulerSingleThreadTaskRunnerManager); |
| }; |
| |
| } // namespace internal |
| } // namespace base |
| |
| #endif // BASE_TASK_SCHEDULER_SCHEDULER_SINGLE_THREAD_TASK_RUNNER_MANAGER_H_ |