nptl/sysdeps/unix/sysv/linux/sparc/sparc32/sem_post.c

   1 /* sem_post -- post to a POSIX semaphore.  SPARC version.
   2    Copyright (C) 2003-2014 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Jakub Jelinek <jakub@redhat.com>, 2003.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <errno.h>
  21 #include <sysdep.h>
  22 #include <lowlevellock.h>
  23 #include <internaltypes.h>
  24 #include <semaphore.h>
  25
  26 #include <shlib-compat.h>
  27
  28 int
  29 __new_sem_post (sem_t *sem)
  30 {
  31   struct sparc_new_sem *isem = (struct sparc_new_sem *) sem;
  32   int nr;
  33
  34   if (__atomic_is_v9)
  35     nr = atomic_increment_val (&isem->value);
  36   else
  37     {
  38       __sparc32_atomic_do_lock24 (&isem->lock);
  39       nr = ++(isem->value);
  40       __sparc32_atomic_do_unlock24 (&isem->lock);
  41     }
  42   atomic_full_barrier ();
  43   if (isem->nwaiters > 0)
  44     {
  45       int err = lll_futex_wake (&isem->value, 1,
  46                                 isem->private ^ FUTEX_PRIVATE_FLAG);
  47       if (__builtin_expect (err, 0) < 0)
  48         {
  49           __set_errno (-err);
  50           return -1;
  51         }
  52     }
  53   return 0;
  54 }
  55 versioned_symbol (libpthread, __new_sem_post, sem_post, GLIBC_2_1);
  56
  57
  58 #if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
  59 int
  60 attribute_compat_text_section
  61 __old_sem_post (sem_t *sem)
  62 {
  63   struct sparc_old_sem *isem = (struct sparc_old_sem *) sem;
  64   int nr;
  65
  66   if (__atomic_is_v9)
  67     nr = atomic_increment_val (&isem->value);
  68   else
  69     {
  70       __sparc32_atomic_do_lock24 (&isem->lock);
  71       nr = ++(isem->value);
  72       __sparc32_atomic_do_unlock24 (&isem->lock);
  73     }
  74   int err = lll_futex_wake (&isem->value, 1,
  75                             isem->private ^ FUTEX_PRIVATE_FLAG);
  76   if (__builtin_expect (err, 0) < 0)
  77     {
  78       __set_errno (-err);
  79       return -1;
  80     }
  81   return 0;
  82 }
  83 compat_symbol (libpthread, __old_sem_post, sem_post, GLIBC_2_0);
  84 #endif