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

   1 /* sem_post -- post to a POSIX semaphore.  SPARC version.
   2    Copyright (C) 2003, 2004, 2006, 2007 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, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #include <errno.h>
  22 #include <sysdep.h>
  23 #include <lowlevellock.h>
  24 #include <internaltypes.h>
  25 #include <semaphore.h>
  26
  27 #include <shlib-compat.h>
  28
  29 int
  30 __new_sem_post (sem_t *sem)
  31 {
  32   struct sparc_new_sem *isem = (struct sparc_new_sem *) sem;
  33   int nr;
  34
  35   if (__atomic_is_v9)
  36     nr = atomic_increment_val (&isem->value);
  37   else
  38     {
  39       __sparc32_atomic_do_lock24 (&isem->lock);
  40       nr = ++(isem->value);
  41       __sparc32_atomic_do_unlock24 (&isem->lock);
  42     }
  43   atomic_full_barrier ();
  44   if (isem->nwaiters > 0)
  45     {
  46       int err = lll_futex_wake (&isem->value, 1,
  47                                 isem->private ^ FUTEX_PRIVATE_FLAG);
  48       if (__builtin_expect (err, 0) < 0)
  49         {
  50           __set_errno (-err);
  51           return -1;
  52         }
  53     }
  54   return 0;
  55 }
  56 versioned_symbol (libpthread, __new_sem_post, sem_post, GLIBC_2_1);
  57
  58
  59 #if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
  60 int
  61 attribute_compat_text_section
  62 __old_sem_post (sem_t *sem)
  63 {
  64   struct sparc_old_sem *isem = (struct sparc_old_sem *) sem;
  65   int nr;
  66
  67   if (__atomic_is_v9)
  68     nr = atomic_increment_val (&isem->value);
  69   else
  70     {
  71       __sparc32_atomic_do_lock24 (&isem->lock);
  72       nr = ++(isem->value);
  73       __sparc32_atomic_do_unlock24 (&isem->lock);
  74     }
  75   int err = lll_futex_wake (&isem->value, 1,
  76                             isem->private ^ FUTEX_PRIVATE_FLAG);
  77   if (__builtin_expect (err, 0) < 0)
  78     {
  79       __set_errno (-err);
  80       return -1;
  81     }
  82   return 0;
  83 }
  84 compat_symbol (libpthread, __old_sem_post, sem_post, GLIBC_2_0);
  85 #endif