1 /* $NetBSD: lock.h,v 1.86 2010/07/01 13:00:57 hannken Exp $ */ 2 3 /*- 4 * Copyright (c) 1999, 2000, 2006, 2007 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center, by Ross Harvey, and by Andrew Doran. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1995 35 * The Regents of the University of California. All rights reserved. 36 * 37 * This code contains ideas from software contributed to Berkeley by 38 * Avadis Tevanian, Jr., Michael Wayne Young, and the Mach Operating 39 * System project at Carnegie-Mellon University. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)lock.h 8.12 (Berkeley) 5/19/95 66 */ 67 68 #ifndef _SYS_LOCK_H_ 69 #define _SYS_LOCK_H_ 70 71 #include <sys/stdint.h> 72 #include <sys/mutex.h> 73 74 #include <machine/lock.h> 75 76 #ifdef _KERNEL 77 78 /* 79 * From <machine/lock.h>. 80 */ 81 #ifndef SPINLOCK_SPIN_HOOK 82 #define SPINLOCK_SPIN_HOOK 83 #endif 84 #ifndef SPINLOCK_BACKOFF_HOOK 85 #define SPINLOCK_BACKOFF_HOOK nullop(NULL) 86 #endif 87 #ifndef SPINLOCK_BACKOFF_MIN 88 #define SPINLOCK_BACKOFF_MIN 4 89 #endif 90 #ifndef SPINLOCK_BACKOFF_MAX 91 #define SPINLOCK_BACKOFF_MAX 128 92 #endif 93 94 #define SPINLOCK_BACKOFF(count) \ 95 do { \ 96 int __i; \ 97 for (__i = (count); __i != 0; __i--) { \ 98 SPINLOCK_BACKOFF_HOOK; \ 99 } \ 100 if ((count) < SPINLOCK_BACKOFF_MAX) \ 101 (count) += (count); \ 102 } while (/* CONSTCOND */ 0); 103 104 #define SPINLOCK_RUN_HOOK(count) ((count) >= SPINLOCK_BACKOFF_MAX) 105 106 #ifdef LOCKDEBUG 107 #define SPINLOCK_SPINOUT(spins) ((spins)++ > 0x0fffffff) 108 #else 109 #define SPINLOCK_SPINOUT(spins) ((void)(spins), 0) 110 #endif 111 112 extern __cpu_simple_lock_t kernel_lock[]; 113 114 #endif /* _KERNEL */ 115 116 #endif /* _SYS_LOCK_H_ */ 117