[glibc.git] / sysdeps / unix / sysv / linux / powerpc / sem_post.c

/* sem_post -- post to a POSIX semaphore.  Powerpc version.
   Copyright (C) 2003-2014 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Paul Mackerras <paulus@au.ibm.com>, 2003.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#include <errno.h>
#include <sysdep.h>
#include <lowlevellock.h>
#include <internaltypes.h>
#include <semaphore.h>

#include <shlib-compat.h>

int
__new_sem_post (sem_t *sem)
{
  struct new_sem *isem = (struct new_sem *) sem;

  __asm __volatile (__lll_rel_instr ::: "memory");
  atomic_increment (&isem->value);
  __asm __volatile (__lll_acq_instr ::: "memory");
  if (isem->nwaiters > 0)
    {
      int err = lll_futex_wake (&isem->value, 1,
				isem->private ^ FUTEX_PRIVATE_FLAG);
      if (__builtin_expect (err, 0) < 0)
	{
	  __set_errno (-err);
	  return -1;
	}
    }
  return 0;
}
versioned_symbol (libpthread, __new_sem_post, sem_post, GLIBC_2_1);

#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)

int
attribute_compat_text_section
__old_sem_post (sem_t *sem)
{
  int *futex = (int *) sem;

  __asm __volatile (__lll_rel_instr ::: "memory");
  (void) atomic_increment_val (futex);
  /* We always have to assume it is a shared semaphore.  */
  int err = lll_futex_wake (futex, 1, LLL_SHARED);
  if (__builtin_expect (err, 0) < 0)
    {
      __set_errno (-err);
      return -1;
    }
  return 0;
}

compat_symbol (libpthread, __old_sem_post, sem_post, GLIBC_2_0);
#endif
Commit	Line	Data
	1	/* sem_post -- post to a POSIX semaphore. Powerpc version.
	2	Copyright (C) 2003-2014 Free Software Foundation, Inc.
	3	This file is part of the GNU C Library.
	4	Contributed by Paul Mackerras <paulus@au.ibm.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 new_sem isem = (struct new_sem ) sem;
	32
	33	__asm __volatile (__lll_rel_instr ::: "memory");
	34	atomic_increment (&isem->value);
	35	__asm __volatile (__lll_acq_instr ::: "memory");
	36	if (isem->nwaiters > 0)
	37	{
	38	int err = lll_futex_wake (&isem->value, 1,
	39	isem->private ^ FUTEX_PRIVATE_FLAG);
	40	if (__builtin_expect (err, 0) < 0)
	41	{
	42	__set_errno (-err);
	43	return -1;
	44	}
	45	}
	46	return 0;
	47	}
	48	versioned_symbol (libpthread, __new_sem_post, sem_post, GLIBC_2_1);
	49
	50	#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_1)
	51
	52	int
	53	attribute_compat_text_section
	54	__old_sem_post (sem_t *sem)
	55	{
	56	int futex = (int ) sem;
	57
	58	__asm __volatile (__lll_rel_instr ::: "memory");
	59	(void) atomic_increment_val (futex);
	60	/* We always have to assume it is a shared semaphore. */
	61	int err = lll_futex_wake (futex, 1, LLL_SHARED);
	62	if (__builtin_expect (err, 0) < 0)
	63	{
	64	__set_errno (-err);
	65	return -1;
	66	}
	67	return 0;
	68	}
	69
	70	compat_symbol (libpthread, __old_sem_post, sem_post, GLIBC_2_0);
	71	#endif