1/* ADJ_FREQ Skew change 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 and
7 *  then uses other tests to detect problems. Thus this test requires
8 *  that the raw_skew, inconsistency-check and nanosleep tests be
9 *  present in the same directory it is run from.
10 *
11 *  To build:
12 *	$ gcc change_skew.c -o change_skew -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 <sys/time.h>
29#include <sys/timex.h>
30#include <time.h>
31#include "../kselftest.h"
32
33#define NSEC_PER_SEC 1000000000LL
34
35
36int change_skew_test(int ppm)
37{
38	struct timex tx;
39	int ret;
40
41	tx.modes = ADJ_FREQUENCY;
42	tx.freq = ppm << 16;
43
44	ret = adjtimex(&tx);
45	if (ret < 0) {
46		printf("Error adjusting freq\n");
47		return ret;
48	}
49
50	ret = system("./raw_skew");
51	ret |= system("./inconsistency-check");
52	ret |= system("./nanosleep");
53
54	return ret;
55}
56
57
58int main(int argc, char **argv)
59{
60	struct timex tx;
61	int i, ret;
62
63	int ppm[5] = {0, 250, 500, -250, -500};
64
65	/* Kill ntpd */
66	ret = system("killall -9 ntpd");
67
68	/* Make sure there's no offset adjustment going on */
69	tx.modes = ADJ_OFFSET;
70	tx.offset = 0;
71	ret = adjtimex(&tx);
72
73	if (ret < 0) {
74		printf("Maybe you're not running as root?\n");
75		return -1;
76	}
77
78	for (i = 0; i < 5; i++) {
79		printf("Using %i ppm adjustment\n", ppm[i]);
80		ret = change_skew_test(ppm[i]);
81		if (ret)
82			break;
83	}
84
85	/* Set things back */
86	tx.modes = ADJ_FREQUENCY;
87	tx.offset = 0;
88	adjtimex(&tx);
89
90	if (ret) {
91		printf("[FAIL]");
92		return ksft_exit_fail();
93	}
94	printf("[OK]");
95	return ksft_exit_pass();
96}
97