1/* ADJ_FREQ Skew consistency test
2 *		by: john stultz (johnstul@us.ibm.com)
3 *		(C) Copyright IBM 2012
4 *		Licensed under the GPLv2
5 *
6 *  NOTE: This is a meta-test which cranks the ADJ_FREQ knob back
7 *  and forth and watches for consistency problems. Thus this test requires
8 *  that the inconsistency-check tests be present in the same directory it
9 *  is run from.
10 *
11 *  To build:
12 *	$ gcc skew_consistency.c -o skew_consistency -lrt
13 *
14 *   This program is free software: you can redistribute it and/or modify
15 *   it under the terms of the GNU General Public License as published by
16 *   the Free Software Foundation, either version 2 of the License, or
17 *   (at your option) any later version.
18 *
19 *   This program is distributed in the hope that it will be useful,
20 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
21 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22 *   GNU General Public License for more details.
23 */
24
25
26#include <stdio.h>
27#include <stdlib.h>
28#include <unistd.h>
29#include <sys/time.h>
30#include <sys/timex.h>
31#include <time.h>
32#include <sys/types.h>
33#include <sys/stat.h>
34#include <fcntl.h>
35#include <string.h>
36#include <sys/wait.h>
37#include "../kselftest.h"
38
39#define NSEC_PER_SEC 1000000000LL
40
41int main(int argc, char **argv)
42{
43	struct timex tx;
44	int ret, ppm;
45	pid_t pid;
46
47
48	printf("Running Asynchronous Frequency Changing Tests...\n");
49
50	pid = fork();
51	if (!pid)
52		return system("./inconsistency-check -c 1 -t 600");
53
54	ppm = 500;
55	ret = 0;
56
57	while (pid != waitpid(pid, &ret, WNOHANG)) {
58		ppm = -ppm;
59		tx.modes = ADJ_FREQUENCY;
60		tx.freq = ppm << 16;
61		adjtimex(&tx);
62		usleep(500000);
63	}
64
65	/* Set things back */
66	tx.modes = ADJ_FREQUENCY;
67	tx.offset = 0;
68	adjtimex(&tx);
69
70
71	if (ret) {
72		printf("[FAILED]\n");
73		return ksft_exit_fail();
74	}
75	printf("[OK]\n");
76	return ksft_exit_pass();
77}
78