LCOM1920-T02G10

/*        $NetBSD: lock.h,v 1.86 2010/07/01 13:00:57 hannken Exp $        */

/*-

 * Copyright (c) 1999, 2000, 2006, 2007 The NetBSD Foundation, Inc.

 * All rights reserved.

 *

 * This code is derived from software contributed to The NetBSD Foundation

 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,

 * NASA Ames Research Center, by Ross Harvey, and by 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.

 *

 * 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.

 */

/*

 * Copyright (c) 1995

 *        The Regents of the University of California.  All rights reserved.

 *

 * This code contains ideas from software contributed to Berkeley by

 * Avadis Tevanian, Jr., Michael Wayne Young, and the Mach Operating

 * System project at Carnegie-Mellon University.

 *

 * 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. Neither the name of the University 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 REGENTS 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 REGENTS 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.

 *

 *        @(#)lock.h        8.12 (Berkeley) 5/19/95

 */

#ifndef        _SYS_LOCK_H_

#define        _SYS_LOCK_H_

#include <sys/stdint.h>

#include <sys/mutex.h>

#include <machine/lock.h>

#ifdef _KERNEL

/*

 * From <machine/lock.h>.

 */

#ifndef SPINLOCK_SPIN_HOOK

#define        SPINLOCK_SPIN_HOOK

#endif

#ifndef SPINLOCK_BACKOFF_HOOK

#define        SPINLOCK_BACKOFF_HOOK                nullop(NULL)

#endif

#ifndef        SPINLOCK_BACKOFF_MIN

#define        SPINLOCK_BACKOFF_MIN        4

#endif

#ifndef        SPINLOCK_BACKOFF_MAX

#define        SPINLOCK_BACKOFF_MAX        128

#endif

#define        SPINLOCK_BACKOFF(count)                                        \

do {                                                                \

        int __i;                                                \

        for (__i = (count); __i != 0; __i--) {                        \

                SPINLOCK_BACKOFF_HOOK;                                \

        }                                                        \

        if ((count) < SPINLOCK_BACKOFF_MAX)                        \

                (count) += (count);                                \

} while (/* CONSTCOND */ 0);

#define        SPINLOCK_RUN_HOOK(count)        ((count) >= SPINLOCK_BACKOFF_MAX)

#ifdef LOCKDEBUG

#define        SPINLOCK_SPINOUT(spins)                ((spins)++ > 0x0fffffff)

#else

#define        SPINLOCK_SPINOUT(spins)                ((void)(spins), 0)

#endif

extern __cpu_simple_lock_t kernel_lock[];

#endif /* _KERNEL */

#endif /* _SYS_LOCK_H_ */