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
50char *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 */
80static 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
91struct 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
101int 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(a: target, b: 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(a: target, b: now))
127 return -1;
128 return 0;
129}
130
131int main(int argc, char **argv)
132{
133 long long length;
134 int clockid, ret;
135
136 ksft_print_header();
137 ksft_set_plan(NR_CLOCKIDS);
138
139 for (clockid = CLOCK_REALTIME; clockid < NR_CLOCKIDS; clockid++) {
140
141 /* Skip cputime clockids since nanosleep won't increment cputime */
142 if (clockid == CLOCK_PROCESS_CPUTIME_ID ||
143 clockid == CLOCK_THREAD_CPUTIME_ID ||
144 clockid == CLOCK_HWSPECIFIC) {
145 ksft_test_result_skip(msg: "%-31s\n", clockstring(clockid));
146 continue;
147 }
148
149 fflush(stdout);
150
151 length = 10;
152 while (length <= (NSEC_PER_SEC * 10)) {
153 ret = nanosleep_test(clockid, ns: length);
154 if (ret == UNSUPPORTED) {
155 ksft_test_result_skip(msg: "%-31s\n", clockstring(clockid));
156 goto next;
157 }
158 if (ret < 0) {
159 ksft_test_result_fail(msg: "%-31s\n", clockstring(clockid));
160 ksft_exit_fail();
161 }
162 length *= 100;
163 }
164 ksft_test_result_pass(msg: "%-31s\n", clockstring(clockid));
165next:
166 ret = 0;
167 }
168 ksft_exit_pass();
169}
170

source code of linux/tools/testing/selftests/timers/nanosleep.c