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
change_skew_test(int ppm)36 int 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
main(int argv,char ** argc)58 int main(int argv, char **argc)
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