1/*
2 * Copyright 2011 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7#include "SysTimer_mach.h"
8
9static time_value_t mac_cpu_time() {
10    mach_port_t task = mach_task_self();
11    if (task == MACH_PORT_NULL) {
12        time_value_t none = {0, 0};
13        return none;
14    }
15
16    task_thread_times_info thread_info_data;
17    mach_msg_type_number_t thread_info_count = TASK_THREAD_TIMES_INFO_COUNT;
18    if (KERN_SUCCESS != task_info(task,
19                                  TASK_THREAD_TIMES_INFO,
20                                  reinterpret_cast<task_info_t>(&thread_info_data),
21                                  &thread_info_count)) {
22        time_value_t none = {0, 0};
23        return none;
24    }
25
26    time_value_add(&thread_info_data.user_time, &thread_info_data.system_time)
27    return thread_info_data.user_time;
28}
29
30static double interval_in_ms(time_value_t start_clock, time_value_t end_clock) {
31    double duration_clock;
32    if ((end_clock.microseconds - start_clock.microseconds) < 0) {
33        duration_clock = (end_clock.seconds - start_clock.seconds-1) * 1000;
34        duration_clock += (1000000 + end_clock.microseconds - start_clock.microseconds) / 1000.0;
35    } else {
36        duration_clock = (end_clock.seconds - start_clock.seconds) * 1000;
37        duration_clock += (end_clock.microseconds - start_clock.microseconds) / 1000.0;
38    }
39    return duration_clock;
40}
41
42void SysTimer::startWall() {
43    fStartWall = mach_absolute_time();
44}
45
46void SysTimer::startCpu() {
47    fStartCpu = mac_cpu_time();
48}
49
50double SysTimer::endCpu() {
51    time_value_t end_cpu = mac_cpu_time();
52    return interval_in_ms(fStartCpu, end_cpu);
53}
54
55double SysTimer::endWall() {
56    uint64_t end_wall = mach_absolute_time();
57
58    uint64_t elapsed = end_wall - fStartWall;
59    mach_timebase_info_data_t sTimebaseInfo;
60    if (KERN_SUCCESS != mach_timebase_info(&sTimebaseInfo)) {
61        return 0;
62    } else {
63        uint64_t elapsedNano = elapsed * sTimebaseInfo.numer / sTimebaseInfo.denom;
64        return elapsedNano / 1000000.0;
65    }
66}
67