components/bookmarks/browser/startup_task_runner_service.h

   1 // Copyright (c) 2013 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 COMPONENTS_BOOKMARKS_BROWSER_STARTUP_TASK_RUNNER_SERVICE_H_
   6 #define COMPONENTS_BOOKMARKS_BROWSER_STARTUP_TASK_RUNNER_SERVICE_H_
   7
   8 #include "base/macros.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/threading/non_thread_safe.h"
  11 #include "components/keyed_service/core/keyed_service.h"
  12
  13 namespace base {
  14 class DeferredSequencedTaskRunner;
  15 class SequencedTaskRunner;
  16 }  // namespace base
  17
  18 namespace bookmarks {
  19
  20 // This service manages the startup task runners.
  21 class StartupTaskRunnerService : public base::NonThreadSafe,
  22                                  public KeyedService {
  23  public:
  24   explicit StartupTaskRunnerService(
  25       const scoped_refptr<base::SequencedTaskRunner>& io_task_runner);
  26   ~StartupTaskRunnerService() override;
  27
  28   // Returns sequenced task runner where all bookmarks I/O operations are
  29   // performed.
  30   // This method should only be called from the UI thread.
  31   // Note: Using a separate task runner per profile service gives a better
  32   // management of the sequence in which the task are started in order to avoid
  33   // congestion during start-up (e.g the caller may decide to start loading the
  34   // bookmarks only after the history finished).
  35   scoped_refptr<base::DeferredSequencedTaskRunner> GetBookmarkTaskRunner();
  36
  37   // Starts the task runners that are deferred during start-up.
  38   void StartDeferredTaskRunners();
  39
  40  private:
  41   scoped_refptr<base::SequencedTaskRunner> io_task_runner_;
  42   scoped_refptr<base::DeferredSequencedTaskRunner> bookmark_task_runner_;
  43
  44   DISALLOW_COPY_AND_ASSIGN(StartupTaskRunnerService);
  45 };
  46
  47 }  // namespace bookmarks
  48
  49 #endif  // COMPONENTS_BOOKMARKS_BROWSER_STARTUP_TASK_RUNNER_SERVICE_H_