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content / browser / scheduler / responsiveness / message_loop_observer.h [blame]
// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CONTENT_BROWSER_SCHEDULER_RESPONSIVENESS_MESSAGE_LOOP_OBSERVER_H_
#define CONTENT_BROWSER_SCHEDULER_RESPONSIVENESS_MESSAGE_LOOP_OBSERVER_H_
#include "base/task/task_observer.h"
namespace base {
struct PendingTask;
} // namespace base
namespace content {
namespace responsiveness {
// This object is not thread safe. It must be constructed and destroyed on the
// same thread. The callbacks will occur synchronously from WillProcessTask()
// and DidProcessTask().
class MessageLoopObserver : base::TaskObserver {
public:
using WillProcessTaskCallback =
base::RepeatingCallback<void(const base::PendingTask* task,
bool was_blocked_or_low_priority)>;
using DidProcessTaskCallback =
base::RepeatingCallback<void(const base::PendingTask* task)>;
// The constructor will register the object as an observer of the current
// MessageLoop. The destructor will unregister the object.
MessageLoopObserver(WillProcessTaskCallback will_process_task_callback,
DidProcessTaskCallback did_process_task_callback);
MessageLoopObserver(const MessageLoopObserver&) = delete;
MessageLoopObserver& operator=(const MessageLoopObserver&) = delete;
~MessageLoopObserver() override;
private:
void WillProcessTask(const base::PendingTask& pending_task,
bool was_blocked_or_low_priority) override;
void DidProcessTask(const base::PendingTask& pending_task) override;
const WillProcessTaskCallback will_process_task_callback_;
const DidProcessTaskCallback did_process_task_callback_;
};
} // namespace responsiveness
} // namespace content
#endif // CONTENT_BROWSER_SCHEDULER_RESPONSIVENESS_MESSAGE_LOOP_OBSERVER_H_