content/child/scheduler/task_queue_selector.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_CHILD_SCHEDULER_TASK_QUEUE_SELECTOR_H_
   6 #define CONTENT_CHILD_SCHEDULER_TASK_QUEUE_SELECTOR_H_
   7
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11
  12 namespace base {
  13 class TaskQueue;
  14 namespace trace_event {
  15 class TracedValue;
  16 }  // namespace trace_event
  17 }  // namespace base
  18
  19 namespace content {
  20
  21 class TaskQueueSelector {
  22  public:
  23   virtual ~TaskQueueSelector() {}
  24
  25   // Called once to register the work queues to be selected from. This function
  26   // is called on the main thread.
  27   virtual void RegisterWorkQueues(
  28       const std::vector<const base::TaskQueue*>& work_queues) = 0;
  29
  30   // Called to choose the work queue from which the next task should be taken
  31   // and run. Return true if |out_queue| indicates the queue to service or
  32   // false to avoid running any task.
  33   //
  34   // This function is called on the main thread.
  35   virtual bool SelectWorkQueueToService(size_t* out_queue_index) = 0;
  36
  37   // Serialize the selector state for tracing.
  38   virtual void AsValueInto(base::trace_event::TracedValue* state) const = 0;
  39 };
  40
  41 }  // namespace content
  42
  43 #endif  // CONTENT_CHILD_SCHEDULER_TASK_QUEUE_SELECTOR_H_