tests/lib/test_seqlock.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * basic test for seqlock
   4  *
   5  * Copyright (C) 2015  David Lamparter
   6  */
   7
   8 #ifdef HAVE_CONFIG_H
   9 #include "config.h"
  10 #endif
  11
  12 #include <stdio.h>
  13 #include <stdint.h>
  14 #include <inttypes.h>
  15 #include <string.h>
  16 #include <unistd.h>
  17 #include <assert.h>
  18 #include <sys/uio.h>
  19
  20 #include "monotime.h"
  21 #include "seqlock.h"
  22 #include "printfrr.h"
  23
  24 static struct seqlock sqlo;
  25 static pthread_t thr1;
  26 static struct timeval start;
  27
  28 static void writestr(const char *str)
  29 {
  30         struct iovec iov[2];
  31         char buf[32];
  32         int64_t usec = monotime_since(&start, NULL);
  33
  34         snprintfrr(buf, sizeof(buf), "[%02" PRId64 "] ", usec / 100000);
  35
  36         iov[0].iov_base = buf;
  37         iov[0].iov_len = strlen(buf);
  38         iov[1].iov_base = (char *)str;
  39         iov[1].iov_len = strlen(str);
  40         writev(1, iov, 2);
  41 }
  42
  43 static void *thr1func(void *arg)
  44 {
  45         assert(!seqlock_held(&sqlo));
  46         assert(seqlock_check(&sqlo, 1));
  47         seqlock_wait(&sqlo, 1);
  48         writestr("thr1 (unheld)\n");
  49
  50         sleep(2);
  51
  52         assert(seqlock_held(&sqlo));
  53         assert(seqlock_check(&sqlo, 1));
  54         seqlock_wait(&sqlo, 1);
  55         writestr("thr1 @1\n");
  56
  57         seqlock_wait(&sqlo, 5);
  58         writestr("thr1 @5\n");
  59
  60         seqlock_wait(&sqlo, 9);
  61         writestr("thr1 @9\n");
  62
  63         seqlock_wait(&sqlo, 13);
  64         writestr("thr1 @13\n");
  65
  66         seqlock_wait(&sqlo, 17);
  67         writestr("thr1 @17\n");
  68
  69         seqlock_wait(&sqlo, 21);
  70         writestr("thr1 @21\n");
  71         return NULL;
  72 }
  73
  74 int main(int argc, char **argv)
  75 {
  76         monotime(&start);
  77
  78         seqlock_init(&sqlo);
  79
  80         assert(!seqlock_held(&sqlo));
  81         seqlock_acquire_val(&sqlo, 1);
  82         assert(seqlock_held(&sqlo));
  83
  84         assert(seqlock_cur(&sqlo) == 1);
  85         assert(seqlock_bump(&sqlo) == 1);
  86         assert(seqlock_cur(&sqlo) == 5);
  87         assert(seqlock_bump(&sqlo) == 5);
  88         assert(seqlock_bump(&sqlo) == 9);
  89         assert(seqlock_bump(&sqlo) == 13);
  90         assert(seqlock_cur(&sqlo) == 17);
  91
  92         assert(seqlock_held(&sqlo));
  93         seqlock_release(&sqlo);
  94         assert(!seqlock_held(&sqlo));
  95
  96         pthread_create(&thr1, NULL, thr1func, NULL);
  97         sleep(1);
  98
  99         writestr("main @5\n");
 100         seqlock_acquire_val(&sqlo, 5);
 101         sleep(2);
 102
 103         writestr("main @9\n");
 104         seqlock_bump(&sqlo);
 105         sleep(1);
 106
 107         writestr("main @17\n");
 108         seqlock_acquire_val(&sqlo, 17);
 109         sleep(1);
 110
 111         writestr("main @release\n");
 112         seqlock_release(&sqlo);
 113         sleep(1);
 114 }