TaskScheduler [9] Delayed Task Manager

base/task_scheduler/scheduler_thread_pool.h

 // Copyright 2016 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_THREAD_POOL_H_
 #define BASE_TASK_SCHEDULER_SCHEDULER_THREAD_POOL_H_
 
 #include <stddef.h>
 
 #include <memory>
 #include <stack>
 #include <vector>
 
 #include "base/base_export.h"
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/synchronization/condition_variable.h"
 #include "base/task_runner.h"
 #include "base/task_scheduler/priority_queue.h"
 #include "base/task_scheduler/scheduler_lock.h"
 #include "base/task_scheduler/scheduler_worker_thread.h"
 #include "base/task_scheduler/sequence.h"
 #include "base/task_scheduler/task_traits.h"
 #include "base/threading/platform_thread.h"
 
 namespace base {
 namespace internal {
 
+class DelayedTaskManager;
 struct SequenceSortKey;
 class TaskTracker;
 
 // A pool of threads that run Tasks. This class is thread-safe.
 class BASE_EXPORT SchedulerThreadPool {
  public:
   // Callback invoked when a Sequence isn't empty after a worker thread pops a
   // Task from it.
   using EnqueueSequenceCallback = Callback<void(scoped_refptr<Sequence>)>;
 
   // Creates a SchedulerThreadPool with up to |max_threads| threads of priority
   // |thread_priority|. |enqueue_sequence_callback| will be invoked after a
-  // thread of this thread pool tries to run a Task. |task_tracker| is used to
-  // handle shutdown behavior of Tasks. Returns nullptr on failure to create a
-  // thread pool with at least one thread.
+  // thread of this thread pool tries to run a Task. Tasks posted to TaskRunners
+  // returned by CreateTaskRunnerWithTraits with a delay are handled by
+  // |delayed_task_manager|. |task_tracker| handles shutdown behavior of Tasks.
+  // Returns nullptr on failure to create a thread pool with at least one
+  // thread.
   static std::unique_ptr<SchedulerThreadPool> CreateThreadPool(
       ThreadPriority thread_priority,
       size_t max_threads,
       const EnqueueSequenceCallback& enqueue_sequence_callback,
-      TaskTracker* task_tracker);
+      TaskTracker* task_tracker,
+      DelayedTaskManager* delayed_task_manager);
 
   // Destroying a SchedulerThreadPool returned by CreateThreadPool() is not
   // allowed in production; it is always leaked. In tests, it can only be
   // destroyed after JoinForTesting() has returned.
   ~SchedulerThreadPool();
 
   // Returns a TaskRunner whose PostTask invocations will result in scheduling
   // Tasks with |traits| and |execution_mode| in this thread pool.
   scoped_refptr<TaskRunner> CreateTaskRunnerWithTraits(
       const TaskTraits& traits,
@@ skipping 10 matching lines @@
   void WaitForAllWorkerThreadsIdleForTesting();
 
   // Joins all threads of this thread pool. Tasks that are already running are
   // allowed to complete their execution. This can only be called once.
   void JoinForTesting();
 
  private:
   class SchedulerWorkerThreadDelegateImpl;
 
   SchedulerThreadPool(const EnqueueSequenceCallback& enqueue_sequence_callback,
-                      TaskTracker* task_tracker);
+                      TaskTracker* task_tracker,
+                      DelayedTaskManager* delayed_task_manager);
 
   bool Initialize(ThreadPriority thread_priority, size_t max_threads);
 
   // Wakes up the last thread from this thread pool to go idle, if any.
   void WakeUpOneThread();
 
   // Adds |worker_thread| to |idle_worker_threads_stack_|.
   void AddToIdleWorkerThreadsStack(SchedulerWorkerThread* worker_thread);
 
   // PriorityQueue from which all threads of this thread pool get work.
@@ skipping 15 matching lines @@
   // Signaled when all worker threads become idle.
   std::unique_ptr<ConditionVariable> idle_worker_threads_stack_cv_for_testing_;
 
   // Signaled once JoinForTesting() has returned.
   WaitableEvent join_for_testing_returned_;
 
   // Delegate for all worker threads in this pool.
   std::unique_ptr<SchedulerWorkerThread::Delegate> worker_thread_delegate_;
 
   TaskTracker* const task_tracker_;
+  DelayedTaskManager* const delayed_task_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(SchedulerThreadPool);
 };
 
 }  // namespace internal
 }  // namespace base
 
 #endif  // BASE_TASK_SCHEDULER_SCHEDULER_THREAD_POOL_H_