nptl/tst-tls7.c

   1 /* Copyright (C) 2013 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18
  19 /* This test checks that TLS in a dlopened object works when first accessed
  20    from a signal handler.  */
  21
  22 #include <assert.h>
  23 #include <atomic.h>
  24 #include <dlfcn.h>
  25 #include <pthread.h>
  26 #include <semaphore.h>
  27 #include <signal.h>
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30
  31 void *
  32 spin (void *ignored)
  33 {
  34   while (1)
  35     {
  36       /* busywork */
  37       free (malloc (128));
  38     }
  39
  40   /* never reached */
  41   return NULL;
  42 }
  43
  44 static void (*tls7mod_action) (int, siginfo_t *, void *);
  45
  46 static void
  47 action (int signo, siginfo_t *info, void *ignored)
  48 {
  49   sem_t *sem = info->si_value.sival_ptr;
  50
  51   atomic_read_barrier ();
  52   assert (tls7mod_action != NULL);
  53   (*tls7mod_action) (signo, info, ignored);
  54
  55   /* This sem_post may trigger dlclose, which will invalidate tls7mod_action.
  56      It is important to do that only after tls7mod_action is no longer
  57      active.  */
  58   sem_post (sem);
  59 }
  60
  61 int
  62 do_test (void)
  63 {
  64   pthread_t th[10];
  65
  66   for (int i = 0; i < 10; ++i)
  67     {
  68       if (pthread_create (&th[i], NULL, spin, NULL))
  69         {
  70           puts ("pthread_create failed");
  71           exit (1);
  72         }
  73     }
  74 #define NITERS 75
  75
  76   for (int i = 0; i < NITERS; ++i)
  77     {
  78       void *h = dlopen ("tst-tls7mod.so", RTLD_LAZY);
  79       if (h == NULL)
  80         {
  81           puts ("dlopen failed");
  82           exit (1);
  83         }
  84
  85       tls7mod_action = dlsym (h, "action");
  86       if (tls7mod_action == NULL)
  87         {
  88           puts ("dlsym for action failed");
  89           exit (1);
  90         }
  91       atomic_write_barrier ();
  92
  93       struct sigaction sa;
  94       sa.sa_sigaction = action;
  95       sigemptyset (&sa.sa_mask);
  96       sa.sa_flags = SA_SIGINFO;
  97       if (sigaction (SIGUSR1, &sa, NULL))
  98         {
  99           puts ("sigaction failed");
 100           exit (1);
 101         }
 102
 103       sem_t sem;
 104       if (sem_init (&sem, 0, 0))
 105         {
 106           puts ("sem_init failed");
 107         }
 108
 109       sigval_t val;
 110       val.sival_ptr = &sem;
 111       for (int i = 0; i < 10; ++i)
 112         {
 113           if (pthread_sigqueue (th[i], SIGUSR1, val))
 114             {
 115               puts ("pthread_sigqueue failed");
 116             }
 117         }
 118
 119
 120       for (int i = 0; i < 10; ++i)
 121         {
 122           if (sem_wait (&sem))
 123           {
 124             puts ("sem_wait failed");
 125           }
 126         }
 127
 128       /* Paranoia.  */
 129       tls7mod_action = NULL;
 130
 131       if (dlclose (h))
 132         {
 133           puts ("dlclose failed");
 134           exit (1);
 135         }
 136     }
 137   return 0;
 138 }
 139
 140 #define TIMEOUT 8
 141
 142 #define TEST_FUNCTION do_test ()
 143 #include "../test-skeleton.c"