nptl/tst-spin2.c

   1 /* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <errno.h>
  21 #include <pthread.h>
  22 #include <stdint.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27 #include <sys/mman.h>
  28 #include <sys/wait.h>
  29
  30
  31 static int
  32 do_test (void)
  33 {
  34 #if ! _POSIX_THREAD_PROCESS_SHARED
  35
  36   puts ("_POSIX_THREAD_PROCESS_SHARED not supported, test skipped");
  37
  38 #else
  39
  40   size_t ps = sysconf (_SC_PAGESIZE);
  41   char tmpfname[] = "/tmp/tst-spin2.XXXXXX";
  42   char data[ps];
  43   void *mem;
  44   int fd;
  45   pthread_spinlock_t *s;
  46   pid_t pid;
  47   char *p;
  48   int err;
  49
  50   fd = mkstemp (tmpfname);
  51   if (fd == -1)
  52     {
  53       printf ("cannot open temporary file: %m\n");
  54       return 1;
  55     }
  56
  57   /* Make sure it is always removed.  */
  58   unlink (tmpfname);
  59
  60   /* Create one page of data.  */
  61   memset (data, '\0', ps);
  62
  63   /* Write the data to the file.  */
  64   if (write (fd, data, ps) != (ssize_t) ps)
  65     {
  66       puts ("short write");
  67       return 1;
  68     }
  69
  70   mem = mmap (NULL, ps, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
  71   if (mem == MAP_FAILED)
  72     {
  73       printf ("mmap failed: %m\n");
  74       return 1;
  75     }
  76
  77   s = (pthread_spinlock_t *) (((uintptr_t) mem
  78                                + __alignof (pthread_spinlock_t))
  79                               & ~(__alignof (pthread_spinlock_t) - 1));
  80   p = (char *) (s + 1);
  81
  82   if (pthread_spin_init (s, PTHREAD_PROCESS_SHARED) != 0)
  83     {
  84       puts ("spin_init failed");
  85       return 1;
  86     }
  87
  88   if (pthread_spin_lock (s) != 0)
  89     {
  90       puts ("spin_lock failed");
  91       return 1;
  92     }
  93
  94   err = pthread_spin_trylock (s);
  95   if (err == 0)
  96     {
  97       puts ("1st spin_trylock succeeded");
  98       return 1;
  99     }
 100   else if (err != EBUSY)
 101     {
 102       puts ("1st spin_trylock didn't return EBUSY");
 103       return 1;
 104     }
 105
 106   err = pthread_spin_unlock (s);
 107   if (err != 0)
 108     {
 109       puts ("parent: spin_unlock failed");
 110       return 1;
 111     }
 112
 113   err = pthread_spin_trylock (s);
 114   if (err != 0)
 115     {
 116       puts ("2nd spin_trylock failed");
 117       return 1;
 118     }
 119
 120   *p = 0;
 121
 122   puts ("going to fork now");
 123   pid = fork ();
 124   if (pid == -1)
 125     {
 126       puts ("fork failed");
 127       return 1;
 128     }
 129   else if (pid == 0)
 130     {
 131       /* Play some lock ping-pong.  It's our turn to unlock first.  */
 132       if ((*p)++ != 0)
 133         {
 134           puts ("child: *p != 0");
 135           return 1;
 136         }
 137
 138       if (pthread_spin_unlock (s) != 0)
 139         {
 140           puts ("child: 1st spin_unlock failed");
 141           return 1;
 142         }
 143
 144       puts ("child done");
 145     }
 146   else
 147     {
 148       if (pthread_spin_lock (s) != 0)
 149         {
 150           puts ("parent: 2nd spin_lock failed");
 151           return 1;
 152         }
 153
 154       puts ("waiting for child");
 155
 156       waitpid (pid, NULL, 0);
 157
 158       puts ("parent done");
 159     }
 160 #endif
 161
 162   return 0;
 163 }
 164
 165 #define TEST_FUNCTION do_test ()
 166 #include "../test-skeleton.c"