tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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 <include/vdso/time64.h>
31#include "../kselftest.h"
32
33/* CLOCK_HWSPECIFIC == CLOCK_SGI_CYCLE (Deprecated) */
34#define CLOCK_HWSPECIFIC 10
35
36#define UNSUPPORTED 0xf00f
37
38char *clockstring(int clockid)
39{
40 switch (clockid) {
41 case CLOCK_REALTIME:
42 return "CLOCK_REALTIME";
43 case CLOCK_MONOTONIC:
44 return "CLOCK_MONOTONIC";
45 case CLOCK_PROCESS_CPUTIME_ID:
46 return "CLOCK_PROCESS_CPUTIME_ID";
47 case CLOCK_THREAD_CPUTIME_ID:
48 return "CLOCK_THREAD_CPUTIME_ID";
49 case CLOCK_MONOTONIC_RAW:
50 return "CLOCK_MONOTONIC_RAW";
51 case CLOCK_REALTIME_COARSE:
52 return "CLOCK_REALTIME_COARSE";
53 case CLOCK_MONOTONIC_COARSE:
54 return "CLOCK_MONOTONIC_COARSE";
55 case CLOCK_BOOTTIME:
56 return "CLOCK_BOOTTIME";
57 case CLOCK_REALTIME_ALARM:
58 return "CLOCK_REALTIME_ALARM";
59 case CLOCK_BOOTTIME_ALARM:
60 return "CLOCK_BOOTTIME_ALARM";
61 case CLOCK_TAI:
62 return "CLOCK_TAI";
63 };
64 return "UNKNOWN_CLOCKID";
65}
66
67/* returns 1 if a <= b, 0 otherwise */
68static inline int in_order(struct timespec a, struct timespec b)
69{
70 if (a.tv_sec < b.tv_sec)
71 return 1;
72 if (a.tv_sec > b.tv_sec)
73 return 0;
74 if (a.tv_nsec > b.tv_nsec)
75 return 0;
76 return 1;
77}
78
79struct timespec timespec_add(struct timespec ts, unsigned long long ns)
80{
81 ts.tv_nsec += ns;
82 while (ts.tv_nsec >= NSEC_PER_SEC) {
83 ts.tv_nsec -= NSEC_PER_SEC;
84 ts.tv_sec++;
85 }
86 return ts;
87}
88
89int nanosleep_test(int clockid, long long ns)
90{
91 struct timespec now, target, rel;
92
93 /* First check abs time */
94 if (clock_gettime(clockid, &now))
95 return UNSUPPORTED;
96 target = timespec_add(now, ns);
97
98 if (clock_nanosleep(clockid, TIMER_ABSTIME, &target, NULL))
99 return UNSUPPORTED;
100 clock_gettime(clockid, &now);
101
102 if (!in_order(target, now))
103 return -1;
104
105 /* Second check reltime */
106 clock_gettime(clockid, &now);
107 rel.tv_sec = 0;
108 rel.tv_nsec = 0;
109 rel = timespec_add(rel, ns);
110 target = timespec_add(now, ns);
111 clock_nanosleep(clockid, 0, &rel, NULL);
112 clock_gettime(clockid, &now);
113
114 if (!in_order(target, now))
115 return -1;
116 return 0;
117}
118
119int main(int argc, char **argv)
120{
121 long long length;
122 int clockid, ret;
123 int max_clocks = CLOCK_TAI + 1;
124
125 ksft_print_header();
126 ksft_set_plan(max_clocks);
127
128 for (clockid = CLOCK_REALTIME; clockid < max_clocks; clockid++) {
129
130 /* Skip cputime clockids since nanosleep won't increment cputime */
131 if (clockid == CLOCK_PROCESS_CPUTIME_ID ||
132 clockid == CLOCK_THREAD_CPUTIME_ID ||
133 clockid == CLOCK_HWSPECIFIC) {
134 ksft_test_result_skip("%-31s\n", clockstring(clockid));
135 continue;
136 }
137
138 fflush(stdout);
139
140 length = 10;
141 while (length <= (NSEC_PER_SEC * 10)) {
142 ret = nanosleep_test(clockid, length);
143 if (ret == UNSUPPORTED) {
144 ksft_test_result_skip("%-31s\n", clockstring(clockid));
145 goto next;
146 }
147 if (ret < 0) {
148 ksft_test_result_fail("%-31s\n", clockstring(clockid));
149 ksft_exit_fail();
150 }
151 length *= 100;
152 }
153 ksft_test_result_pass("%-31s\n", clockstring(clockid));
154next:
155 ret = 0;
156 }
157 ksft_exit_pass();
158}