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/* $OpenBSD: i80321_mutex.c,v 1.3 2009/08/13 19:39:46 deraadt Exp $ */
/*
* Copyright (c) 2004 Artur Grabowski <art@openbsd.org>
* All rights reserved.
*
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``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 AUTHOR 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.
*/
#include <sys/param.h>
#include <sys/mutex.h>
#include <sys/systm.h>
#include <machine/intr.h>
#ifdef MULTIPROCESSOR
#error This code needs work
#endif
/*
* Single processor systems don't need any mutexes, but they need the spl
* raising semantics of the mutexes.
*/
void
mtx_init(struct mutex *mtx, int wantipl)
{
mtx->mtx_oldipl = 0;
mtx->mtx_wantipl = wantipl;
mtx->mtx_lock = 0;
}
void
mtx_enter(struct mutex *mtx)
{
if (mtx->mtx_wantipl != IPL_NONE)
mtx->mtx_oldipl = _splraise(mtx->mtx_wantipl);
MUTEX_ASSERT_UNLOCKED(mtx);
mtx->mtx_lock = 1;
}
int
mtx_enter_try(struct mutex *mtx)
{
if (mtx->mtx_wantipl != IPL_NONE)
mtx->mtx_oldipl = _splraise(mtx->mtx_wantipl);
MUTEX_ASSERT_UNLOCKED(mtx);
mtx->mtx_lock = 1;
return 1;
}
void
mtx_leave(struct mutex *mtx)
{
MUTEX_ASSERT_LOCKED(mtx);
mtx->mtx_lock = 0;
if (mtx->mtx_wantipl != IPL_NONE)
splx(mtx->mtx_oldipl);
}
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