1 /* Make sure timers don't return early
2 * by: john stultz (johnstul@us.ibm.com)
3 * John Stultz (john.stultz@linaro.org)
4 * (C) Copyright IBM 2012
5 * (C) Copyright Linaro 2013 2015
6 * Licensed under the GPLv2
7 *
8 * To build:
9 * $ gcc nanosleep.c -o nanosleep -lrt
10 *
11 * This program is free software: you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation, either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 */
21
22 #include <errno.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <time.h>
26 #include <sys/time.h>
27 #include <sys/timex.h>
28 #include <string.h>
29 #include <signal.h>
30 #include "../kselftest.h"
31
32 #define NSEC_PER_SEC 1000000000ULL
33
34 #define CLOCK_REALTIME 0
35 #define CLOCK_MONOTONIC 1
36 #define CLOCK_PROCESS_CPUTIME_ID 2
37 #define CLOCK_THREAD_CPUTIME_ID 3
38 #define CLOCK_MONOTONIC_RAW 4
39 #define CLOCK_REALTIME_COARSE 5
40 #define CLOCK_MONOTONIC_COARSE 6
41 #define CLOCK_BOOTTIME 7
42 #define CLOCK_REALTIME_ALARM 8
43 #define CLOCK_BOOTTIME_ALARM 9
44 #define CLOCK_HWSPECIFIC 10
45 #define CLOCK_TAI 11
46 #define NR_CLOCKIDS 12
47
48 #define UNSUPPORTED 0xf00f
49
clockstring(int clockid)50 char *clockstring(int clockid)
51 {
52 switch (clockid) {
53 case CLOCK_REALTIME:
54 return "CLOCK_REALTIME";
55 case CLOCK_MONOTONIC:
56 return "CLOCK_MONOTONIC";
57 case CLOCK_PROCESS_CPUTIME_ID:
58 return "CLOCK_PROCESS_CPUTIME_ID";
59 case CLOCK_THREAD_CPUTIME_ID:
60 return "CLOCK_THREAD_CPUTIME_ID";
61 case CLOCK_MONOTONIC_RAW:
62 return "CLOCK_MONOTONIC_RAW";
63 case CLOCK_REALTIME_COARSE:
64 return "CLOCK_REALTIME_COARSE";
65 case CLOCK_MONOTONIC_COARSE:
66 return "CLOCK_MONOTONIC_COARSE";
67 case CLOCK_BOOTTIME:
68 return "CLOCK_BOOTTIME";
69 case CLOCK_REALTIME_ALARM:
70 return "CLOCK_REALTIME_ALARM";
71 case CLOCK_BOOTTIME_ALARM:
72 return "CLOCK_BOOTTIME_ALARM";
73 case CLOCK_TAI:
74 return "CLOCK_TAI";
75 };
76 return "UNKNOWN_CLOCKID";
77 }
78
79 /* returns 1 if a <= b, 0 otherwise */
in_order(struct timespec a,struct timespec b)80 static inline int in_order(struct timespec a, struct timespec b)
81 {
82 if (a.tv_sec < b.tv_sec)
83 return 1;
84 if (a.tv_sec > b.tv_sec)
85 return 0;
86 if (a.tv_nsec > b.tv_nsec)
87 return 0;
88 return 1;
89 }
90
timespec_add(struct timespec ts,unsigned long long ns)91 struct timespec timespec_add(struct timespec ts, unsigned long long ns)
92 {
93 ts.tv_nsec += ns;
94 while (ts.tv_nsec >= NSEC_PER_SEC) {
95 ts.tv_nsec -= NSEC_PER_SEC;
96 ts.tv_sec++;
97 }
98 return ts;
99 }
100
nanosleep_test(int clockid,long long ns)101 int nanosleep_test(int clockid, long long ns)
102 {
103 struct timespec now, target, rel;
104
105 /* First check abs time */
106 if (clock_gettime(clockid, &now))
107 return UNSUPPORTED;
108 target = timespec_add(now, ns);
109
110 if (clock_nanosleep(clockid, TIMER_ABSTIME, &target, NULL))
111 return UNSUPPORTED;
112 clock_gettime(clockid, &now);
113
114 if (!in_order(target, now))
115 return -1;
116
117 /* Second check reltime */
118 clock_gettime(clockid, &now);
119 rel.tv_sec = 0;
120 rel.tv_nsec = 0;
121 rel = timespec_add(rel, ns);
122 target = timespec_add(now, ns);
123 clock_nanosleep(clockid, 0, &rel, NULL);
124 clock_gettime(clockid, &now);
125
126 if (!in_order(target, now))
127 return -1;
128 return 0;
129 }
130
main(int argc,char ** argv)131 int main(int argc, char **argv)
132 {
133 long long length;
134 int clockid, ret;
135
136 for (clockid = CLOCK_REALTIME; clockid < NR_CLOCKIDS; clockid++) {
137
138 /* Skip cputime clockids since nanosleep won't increment cputime */
139 if (clockid == CLOCK_PROCESS_CPUTIME_ID ||
140 clockid == CLOCK_THREAD_CPUTIME_ID ||
141 clockid == CLOCK_HWSPECIFIC)
142 continue;
143
144 printf("Nanosleep %-31s ", clockstring(clockid));
145 fflush(stdout);
146
147 length = 10;
148 while (length <= (NSEC_PER_SEC * 10)) {
149 ret = nanosleep_test(clockid, length);
150 if (ret == UNSUPPORTED) {
151 printf("[UNSUPPORTED]\n");
152 goto next;
153 }
154 if (ret < 0) {
155 printf("[FAILED]\n");
156 return ksft_exit_fail();
157 }
158 length *= 100;
159 }
160 printf("[OK]\n");
161 next:
162 ret = 0;
163 }
164 return ksft_exit_pass();
165 }
166