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
41 int 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 ksft_exit_fail();
74 }
75 printf("[OK]\n");
76 ksft_exit_pass();
77 }
78
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