kernel/test/synch/rwlock2.c

   1 /*
   2  * Copyright (c) 2001-2004 Jakub Jermar
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include <test.h>
  30 #include <arch.h>
  31 #include <atomic.h>
  32 #include <print.h>
  33 #include <proc/thread.h>
  34
  35 #include <synch/rwlock.h>
  36
  37 #define READERS         50
  38 #define WRITERS         50
  39
  40 static rwlock_t rwlock;
  41 static bool sh_quiet;
  42
  43 static void writer(void *arg)
  44 {
  45         if (!sh_quiet)
  46                 printf("Trying to lock rwlock for writing....\n");
  47
  48         rwlock_write_lock(&rwlock);
  49         rwlock_write_unlock(&rwlock);
  50
  51         if (!sh_quiet)
  52                 printf("Trying to lock rwlock for reading....\n");
  53
  54         rwlock_read_lock(&rwlock);
  55         rwlock_read_unlock(&rwlock);
  56 }
  57
  58 char * test_rwlock2(bool quiet)
  59 {
  60         thread_t *thrd;
  61         sh_quiet = quiet;
  62
  63         rwlock_initialize(&rwlock);
  64
  65         rwlock_read_lock(&rwlock);
  66         rwlock_read_lock(&rwlock);
  67         rwlock_read_lock(&rwlock);
  68         rwlock_read_lock(&rwlock);
  69
  70         thrd = thread_create(writer, NULL, TASK, 0, "writer", false);
  71         if (thrd)
  72                 thread_ready(thrd);
  73         else
  74                 return "Could not create thread";
  75
  76         thread_sleep(1);
  77
  78         rwlock_read_unlock(&rwlock);
  79         rwlock_read_unlock(&rwlock);
  80         rwlock_read_unlock(&rwlock);
  81         rwlock_read_unlock(&rwlock);
  82
  83         thread_join(thrd);
  84         thread_detach(thrd);
  85
  86         return NULL;
  87 }