usr/src/test/libc-tests/tests/call_once.c

   1 /*
   2  * This file and its contents are supplied under the terms of the
   3  * Common Development and Distribution License ("CDDL"), version 1.0.
   4  * You may only use this file in accordance with the terms of version
   5  * 1.0 of the CDDL.
   6  *
   7  * A full copy of the text of the CDDL should have accompanied this
   8  * source.  A copy of the CDDL is also available via the Internet at
   9  * http://www.illumos.org/license/CDDL.
  10  */
  11
  12 /*
  13  * Copyright 2016 Joyent, Inc.
  14  */
  15
  16 /*
  17  * Test call_once(3C)
  18  */
  19
  20 #include <threads.h>
  21 #include <sys/debug.h>
  22
  23 #define CO_NTHREADS     32
  24
  25 static int co_val = 41;
  26 static mtx_t co_once_mtx;
  27 static mtx_t co_mtx;
  28 static boolean_t co_go = B_FALSE;
  29 static once_flag co_once = ONCE_FLAG_INIT;
  30 static cnd_t co_cnd;
  31
  32 static void
  33 co_once_func(void)
  34 {
  35         VERIFY3S(mtx_lock(&co_once_mtx), ==, thrd_success);
  36         co_val++;
  37         VERIFY3S(mtx_unlock(&co_once_mtx), ==, thrd_success);
  38 }
  39
  40 /*ARGSUSED*/
  41 static int
  42 co_thr(void *arg)
  43 {
  44         VERIFY3S(mtx_lock(&co_mtx), ==, thrd_success);
  45         while (co_go == B_FALSE) {
  46                 (void) cnd_wait(&co_cnd, &co_mtx);
  47         }
  48         VERIFY3S(mtx_unlock(&co_mtx), ==, thrd_success);
  49         call_once(&co_once, co_once_func);
  50         return (0);
  51 }
  52
  53 int
  54 main(void)
  55 {
  56         int i;
  57         thrd_t threads[CO_NTHREADS];
  58
  59         VERIFY3S(mtx_init(&co_once_mtx, mtx_plain), ==, thrd_success);
  60         VERIFY3S(mtx_init(&co_mtx, mtx_plain), ==, thrd_success);
  61         VERIFY3S(cnd_init(&co_cnd), ==, thrd_success);
  62
  63         for (i = 0; i < CO_NTHREADS; i++) {
  64                 VERIFY3S(thrd_create(&threads[i], co_thr, NULL), ==,
  65                     thrd_success);
  66         }
  67
  68         VERIFY3S(mtx_lock(&co_mtx), ==, thrd_success);
  69         co_go = B_TRUE;
  70         VERIFY3S(mtx_unlock(&co_mtx), ==, thrd_success);
  71         VERIFY3S(cnd_broadcast(&co_cnd), ==, thrd_success);
  72
  73         for (i = 0; i < CO_NTHREADS; i++) {
  74                 VERIFY3S(thrd_join(threads[i], NULL), ==, thrd_success);
  75         }
  76         VERIFY3S(co_val, ==, 42);
  77
  78         return (0);
  79 }