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

   1 /* sem_post -- post to a POSIX semaphore.  SPARC version.
   2    Copyright (C) 2003-2013 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
  33   atomic_increment (&isem->value);
  34   atomic_full_barrier ();
  35   if (isem->nwaiters > 0)
  36     {
  37       int err = lll_futex_wake (&isem->value, 1,
  38                                 isem->private ^ FUTEX_PRIVATE_FLAG);
  39       if (__builtin_expect (err, 0) < 0)
  40         {
  41           __set_errno (-err);
  42           return -1;
  43         }
  44     }
  45   return 0;
  46 }
  47 versioned_symbol (libpthread, __new_sem_post, sem_post, GLIBC_2_1);
  48
  49
  50 #if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
  51 int
  52 attribute_compat_text_section
  53 __old_sem_post (sem_t *sem)
  54 {
  55   struct sparc_old_sem *isem = (struct sparc_old_sem *) sem;
  56   int err;
  57
  58   atomic_increment (&isem->value);
  59   err = lll_futex_wake (&isem->value, 1,
  60                         isem->private ^ FUTEX_PRIVATE_FLAG);
  61   if (__builtin_expect (err, 0) < 0)
  62     {
  63       __set_errno (-err);
  64       return -1;
  65     }
  66   return 0;
  67 }
  68 compat_symbol (libpthread, __old_sem_post, sem_post, GLIBC_2_0);
  69 #endif