tests/kernel/t_time.c

   1 /* $NetBSD$ */
   2
   3 /*-
   4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Frank Kardel.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 /*-
  33  * Copyright (c) 2006 Frank Kardel
  34  * All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  * 1. Redistributions of source code must retain the above copyright
  40  *    notice, this list of conditions and the following disclaimer.
  41  * 2. Redistributions in binary form must reproduce the above copyright
  42  *    notice, this list of conditions and the following disclaimer in the
  43  *    documentation and/or other materials provided with the distribution.
  44  *
  45  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  46  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  47  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  48  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  49  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  50  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  51  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  52  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  53  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  54  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  55  * POSSIBILITY OF SUCH DAMAGE.
  56  */
  57
  58 #include <sys/cdefs.h>
  59 __COPYRIGHT("@(#) Copyright (c) 2008\
  60  The NetBSD Foundation, inc. All rights reserved.");
  61 __RCSID("$NetBSD$");
  62
  63 #include <sys/param.h>
  64 #include <sys/sysctl.h>
  65
  66 #include <machine/int_limits.h>
  67
  68 #include <errno.h>
  69 #include <stdio.h>
  70 #include <stdlib.h>
  71 #include <string.h>
  72 #include <time.h>
  73 #include <unistd.h>
  74
  75 #include <atf-c.h>
  76
  77 #include "../h_macros.h"
  78
  79 #define MINPOSDIFF      15000000        /* 15 ms for now */
  80 #define TIMEOUT         5
  81
  82 #define TC_HARDWARE     "kern.timecounter.hardware"
  83 #define TC_CHOICE       "kern.timecounter.choice"
  84
  85 static void
  86 check_timecounter(void)
  87 {
  88         struct timespec tsa, tsb, tsl, res;
  89         long long mindiff = INTMAX_MAX;
  90         time_t endlimit;
  91
  92 #define CL(x) \
  93         do { \
  94                 if ((x) != -1) \
  95                         break; \
  96                 atf_tc_fail_nonfatal("%s: %s", #x, strerror(errno)); \
  97                 return; \
  98         } while (0)
  99
 100         CL(clock_gettime(CLOCK_REALTIME, &tsa));
 101         tsl = tsa;
 102
 103         CL(time(&endlimit));
 104         endlimit += TIMEOUT + 1;
 105
 106         while ((time_t)tsa.tv_sec < endlimit) {
 107                 long long diff;
 108
 109                 CL(clock_gettime(CLOCK_REALTIME, &tsb));
 110                 diff = 1000000000LL * (tsb.tv_sec - tsa.tv_sec)
 111                     + tsb.tv_nsec - tsa.tv_nsec;
 112
 113                 if (diff > 0 && mindiff > diff)
 114                         mindiff = diff;
 115
 116                 if (diff < 0 || diff > MINPOSDIFF) {
 117                         long long elapsed;
 118                         (void)printf("%stime TSA: 0x%jx.%08jx, TSB: 0x%jx.%08jx, "
 119                             "diff = %lld nsec, ", (diff < 0) ? "BAD " : "",
 120                             (uintmax_t)tsa.tv_sec, (uintmax_t)tsa.tv_nsec,
 121                             (uintmax_t)tsb.tv_sec, (uintmax_t)tsb.tv_nsec, diff);
 122
 123                         elapsed = 1000000000LL * (tsb.tv_sec - tsl.tv_sec)
 124                             + tsb.tv_nsec - tsl.tv_nsec;
 125
 126
 127                         (void)printf("%lld nsec\n", elapsed);
 128                         tsl = tsb;
 129
 130                         ATF_CHECK(diff >= 0);
 131                         if (diff < 0)
 132                                 return;
 133                 }
 134
 135                 tsa.tv_sec = tsb.tv_sec;
 136                 tsa.tv_nsec = tsb.tv_nsec;
 137         }
 138
 139         if (clock_getres(CLOCK_REALTIME, &res) == 0) {
 140                 long long r = res.tv_sec * 1000000000 + res.tv_nsec;
 141
 142                 (void)printf("Claimed resolution: %lld nsec (%f Hz) or "
 143                     "better\n", r, 1.0 / r * 1e9);
 144                 (void)printf("Observed minimum non zero delta: %lld "
 145                     "nsec\n", mindiff);
 146         }
 147
 148 #undef CL
 149 }
 150
 151 ATF_TC(time);
 152 ATF_TC_HEAD(time, tc)
 153 {
 154         atf_tc_set_md_var(tc, "require.user", "root");
 155         atf_tc_set_md_var(tc, "descr",
 156             "Checks the monotonicity of the CLOCK_REALTIME implementation");
 157 }
 158 ATF_TC_BODY(time, tc)
 159 {
 160         char name[128], cbuf[512], ctrbuf[10240];
 161         size_t cbufsiz = sizeof(cbuf);
 162         size_t ctrbufsiz = sizeof(ctrbuf);
 163         const char *p;
 164         char *save;
 165         int quality, n;
 166
 167         if (sysctlbyname(TC_HARDWARE, cbuf, &cbufsiz, NULL, 0) != 0) {
 168                 (void)printf("\nChecking legacy time implementation "
 169                     "for %d seconds\n", TIMEOUT);
 170                 check_timecounter();
 171                 return;
 172                 /* NOTREACHED */
 173         }
 174         (void)printf("%s = %s\n", TC_HARDWARE, cbuf);
 175         REQUIRE_LIBC(save = strdup(cbuf), NULL);
 176
 177         RL(sysctlbyname(TC_CHOICE, ctrbuf, &ctrbufsiz, NULL, 0));
 178         (void)printf("%s = %s\n", TC_CHOICE, ctrbuf);
 179
 180         for (p = ctrbuf, n = 0; sscanf(p, "%127[^(](q=%d, f=%*u Hz)%*[ ]%n",
 181             name, &quality, &n) == 2; p += n) {
 182                 struct timespec ts;
 183                 int ret;
 184
 185                 if (quality < 0)
 186                         continue;
 187
 188                 (void)printf("\nChecking %s for %d seconds\n", name, TIMEOUT);
 189                 CHECK_LIBC(ret = sysctlbyname(TC_HARDWARE, NULL, 0,
 190                     name, strlen(name)), -1);
 191                 if (ret == -1)
 192                         continue;
 193
 194                 /* wait a bit to select new counter in clockinterrupt */
 195                 ts.tv_sec = 0;
 196                 ts.tv_nsec = 100000000;
 197                 (void)nanosleep(&ts, NULL);
 198
 199                 check_timecounter();
 200         }
 201
 202         RL(sysctlbyname(TC_HARDWARE, NULL, 0, save, strlen(save)));
 203 }
 204
 205 ATF_TP_ADD_TCS(tp)
 206 {
 207         ATF_TP_ADD_TC(tp, time);
 208
 209         return atf_no_error();
 210 }