1/*	$OpenBSD: hertz.c,v 1.7 2015/01/16 06:40:08 deraadt Exp $	*/
2
3/*
4 * Copyright (c) 2005 Artur Grabowski <art@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19
20#include <sys/time.h>
21#include <sys/sysctl.h>
22
23#include "gprof.h"
24
25/*
26 * Return the tick frequency on the machine or 0 if we can't find out.
27 */
28
29int
30hertz(void)
31{
32	struct clockinfo cinfo;
33	int mib[2];
34	size_t len;
35
36	mib[0] = CTL_KERN;
37	mib[1] = KERN_CLOCKRATE;
38	len = sizeof(cinfo);
39	if (sysctl(mib, 2, &cinfo, &len, NULL, 0) == -1)
40		return (0);
41
42	return (cinfo.hz);
43}
44