kernel/tools/testing/selftests/timers/nanosleep.c

   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 <stdio.h>
  23 #include <stdlib.h>
  24 #include <time.h>
  25 #include <sys/time.h>
  26 #include <sys/timex.h>
  27 #include <string.h>
  28 #include <signal.h>
  29 #ifdef KTEST
  30 #include "../kselftest.h"
  31 #else
  32 static inline int ksft_exit_pass(void)
  33 {
  34         exit(0);
  35 }
  36 static inline int ksft_exit_fail(void)
  37 {
  38         exit(1);
  39 }
  40 #endif
  41
  42 #define NSEC_PER_SEC 1000000000ULL
  43
  44 #define CLOCK_REALTIME                  0
  45 #define CLOCK_MONOTONIC                 1
  46 #define CLOCK_PROCESS_CPUTIME_ID        2
  47 #define CLOCK_THREAD_CPUTIME_ID         3
  48 #define CLOCK_MONOTONIC_RAW             4
  49 #define CLOCK_REALTIME_COARSE           5
  50 #define CLOCK_MONOTONIC_COARSE          6
  51 #define CLOCK_BOOTTIME                  7
  52 #define CLOCK_REALTIME_ALARM            8
  53 #define CLOCK_BOOTTIME_ALARM            9
  54 #define CLOCK_HWSPECIFIC                10
  55 #define CLOCK_TAI                       11
  56 #define NR_CLOCKIDS                     12
  57
  58 #define UNSUPPORTED 0xf00f
  59
  60 char *clockstring(int clockid)
  61 {
  62         switch (clockid) {
  63         case CLOCK_REALTIME:
  64                 return "CLOCK_REALTIME";
  65         case CLOCK_MONOTONIC:
  66                 return "CLOCK_MONOTONIC";
  67         case CLOCK_PROCESS_CPUTIME_ID:
  68                 return "CLOCK_PROCESS_CPUTIME_ID";
  69         case CLOCK_THREAD_CPUTIME_ID:
  70                 return "CLOCK_THREAD_CPUTIME_ID";
  71         case CLOCK_MONOTONIC_RAW:
  72                 return "CLOCK_MONOTONIC_RAW";
  73         case CLOCK_REALTIME_COARSE:
  74                 return "CLOCK_REALTIME_COARSE";
  75         case CLOCK_MONOTONIC_COARSE:
  76                 return "CLOCK_MONOTONIC_COARSE";
  77         case CLOCK_BOOTTIME:
  78                 return "CLOCK_BOOTTIME";
  79         case CLOCK_REALTIME_ALARM:
  80                 return "CLOCK_REALTIME_ALARM";
  81         case CLOCK_BOOTTIME_ALARM:
  82                 return "CLOCK_BOOTTIME_ALARM";
  83         case CLOCK_TAI:
  84                 return "CLOCK_TAI";
  85         };
  86         return "UNKNOWN_CLOCKID";
  87 }
  88
  89 /* returns 1 if a <= b, 0 otherwise */
  90 static inline int in_order(struct timespec a, struct timespec b)
  91 {
  92         if (a.tv_sec < b.tv_sec)
  93                 return 1;
  94         if (a.tv_sec > b.tv_sec)
  95                 return 0;
  96         if (a.tv_nsec > b.tv_nsec)
  97                 return 0;
  98         return 1;
  99 }
 100
 101 struct timespec timespec_add(struct timespec ts, unsigned long long ns)
 102 {
 103         ts.tv_nsec += ns;
 104         while (ts.tv_nsec >= NSEC_PER_SEC) {
 105                 ts.tv_nsec -= NSEC_PER_SEC;
 106                 ts.tv_sec++;
 107         }
 108         return ts;
 109 }
 110
 111 int nanosleep_test(int clockid, long long ns)
 112 {
 113         struct timespec now, target, rel;
 114
 115         /* First check abs time */
 116         if (clock_gettime(clockid, &now))
 117                 return UNSUPPORTED;
 118         target = timespec_add(now, ns);
 119
 120         if (clock_nanosleep(clockid, TIMER_ABSTIME, &target, NULL))
 121                 return UNSUPPORTED;
 122         clock_gettime(clockid, &now);
 123
 124         if (!in_order(target, now))
 125                 return -1;
 126
 127         /* Second check reltime */
 128         clock_gettime(clockid, &now);
 129         rel.tv_sec = 0;
 130         rel.tv_nsec = 0;
 131         rel = timespec_add(rel, ns);
 132         target = timespec_add(now, ns);
 133         clock_nanosleep(clockid, 0, &rel, NULL);
 134         clock_gettime(clockid, &now);
 135
 136         if (!in_order(target, now))
 137                 return -1;
 138         return 0;
 139 }
 140
 141 int main(int argc, char **argv)
 142 {
 143         long long length;
 144         int clockid, ret;
 145
 146         for (clockid = CLOCK_REALTIME; clockid < NR_CLOCKIDS; clockid++) {
 147
 148                 /* Skip cputime clockids since nanosleep won't increment cputime */
 149                 if (clockid == CLOCK_PROCESS_CPUTIME_ID ||
 150                                 clockid == CLOCK_THREAD_CPUTIME_ID ||
 151                                 clockid == CLOCK_HWSPECIFIC)
 152                         continue;
 153
 154                 printf("Nanosleep %-31s ", clockstring(clockid));
 155
 156                 length = 10;
 157                 while (length <= (NSEC_PER_SEC * 10)) {
 158                         ret = nanosleep_test(clockid, length);
 159                         if (ret == UNSUPPORTED) {
 160                                 printf("[UNSUPPORTED]\n");
 161                                 goto next;
 162                         }
 163                         if (ret < 0) {
 164                                 printf("[FAILED]\n");
 165                                 return ksft_exit_fail();
 166                         }
 167                         length *= 100;
 168                 }
 169                 printf("[OK]\n");
 170 next:
 171                 ret = 0;
 172         }
 173         return ksft_exit_pass();
 174 }