NetBSD/sys/arch/arm/include/rwlock.h
ad afb9be47ba - Change _lock_cas() to do compare-and-swap instead of compare-and-set.
- Add aliases for atomic_cas_ulong() and friends.
2007-11-29 15:17:45 +00:00

62 lines
2.4 KiB
C

/* $NetBSD: rwlock.h,v 1.4 2007/11/29 15:17:45 ad Exp $ */
/*-
* Copyright (c) 2002, 2006 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe and Andrew Doran.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _ARM_RWLOCK_H_
#define _ARM_RWLOCK_H_
struct krwlock {
volatile uintptr_t rw_owner;
};
#ifdef __RWLOCK_PRIVATE
#define __HAVE_SIMPLE_RW_LOCKS 1
#define RW_RECEIVE(rw) /* nothing */
#define RW_GIVE(rw) /* nothing */
unsigned long _lock_cas(volatile unsigned long *,
unsigned long, unsigned long);
#define RW_CAS(p, o, n) \
(_lock_cas((volatile unsigned long *)(p), (o), (n)) == (o))
#endif /* __RWLOCK_PRIVATE */
#endif /* _ARM_RWLOCK_H_ */