rt_gccstream/libgomp/config/linux/ptrlock.h

63 lines
2.1 KiB
C

/* Copyright (C) 2008, 2009 Free Software Foundation, Inc.
Contributed by Jakub Jelinek <jakub@redhat.com>.
This file is part of the GNU OpenMP Library (libgomp).
Libgomp is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
Libgomp 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 General Public License for
more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* This is a Linux specific implementation of a mutex synchronization
mechanism for libgomp. This type is private to the library. This
implementation uses atomic instructions and the futex syscall. */
#ifndef GOMP_PTRLOCK_H
#define GOMP_PTRLOCK_H 1
typedef void *gomp_ptrlock_t;
static inline void gomp_ptrlock_init (gomp_ptrlock_t *ptrlock, void *ptr)
{
*ptrlock = ptr;
}
extern void *gomp_ptrlock_get_slow (gomp_ptrlock_t *ptrlock);
static inline void *gomp_ptrlock_get (gomp_ptrlock_t *ptrlock)
{
if ((uintptr_t) *ptrlock > 2)
return *ptrlock;
if (__sync_bool_compare_and_swap (ptrlock, NULL, (uintptr_t) 1))
return NULL;
return gomp_ptrlock_get_slow (ptrlock);
}
extern void gomp_ptrlock_set_slow (gomp_ptrlock_t *ptrlock, void *ptr);
static inline void gomp_ptrlock_set (gomp_ptrlock_t *ptrlock, void *ptr)
{
if (!__sync_bool_compare_and_swap (ptrlock, (uintptr_t) 1, ptr))
gomp_ptrlock_set_slow (ptrlock, ptr);
}
static inline void gomp_ptrlock_destroy (gomp_ptrlock_t *ptrlock)
{
}
#endif /* GOMP_PTRLOCK_H */