js/ipc/CPOWTimer.h
author maliu <max@mxli.us>
Wed, 25 Oct 2017 22:51:44 +0800
changeset 388396 31f87080283b1dc558f3781e0ec2ca59d102de82
parent 262213 31a26ed444843f086c468a98236e8c98b7115b44
child 448947 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1360587 - Part 2. Remove bouncer apk build config; source; docs, r=nalexander MozReview-Commit-ID: C1QJcr65yWu

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=4 sw=4 et tw=80:
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef CPOWTIMER_H
#define CPOWTIMER_H

#include "prinrval.h"
#include "jsapi.h"

/**
 * A stopwatch measuring the duration of a CPOW call.
 *
 * As the process is consuming neither user time nor system time
 * during a CPOW call, we measure such durations using wallclock time.
 *
 * This stopwatch is active iff JSRuntime::stopwatch.isActive is set.
 * Upon destruction, update JSRuntime::stopwatch.data.totalCPOWTime.
 */
class MOZ_RAII CPOWTimer final {
  public:
    explicit inline CPOWTimer(JSContext* cx MOZ_GUARD_OBJECT_NOTIFIER_PARAM);
    ~CPOWTimer();

  private:
    MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER

    /**
     * The context in which this timer was created, or `nullptr` if
     * CPOW monitoring was off when the timer was created.
     */
    JSContext* cx_;

    /**
     * The instant at which the stopwatch was started. Undefined
     * if CPOW monitoring was off when the timer was created.
     */
    int64_t startInterval_;
};

#endif