1/* $NetBSD: lock.h,v 1.28 2008/02/23 05:48:13 matt Exp $ */ 2 3/* 4 * Copyright (c) 2000 Ludd, University of Lule}, Sweden. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed at Ludd, University of Lule}. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33#ifndef _VAX_LOCK_H_ 34#define _VAX_LOCK_H_ 35 36#include <sys/param.h> 37 38#ifdef _KERNEL 39#ifdef _KERNEL_OPT 40#include "opt_multiprocessor.h" 41#include <machine/intr.h> 42#endif 43#include <machine/cpu.h> 44#endif 45 46static __inline int 47__SIMPLELOCK_LOCKED_P(__cpu_simple_lock_t *__ptr) 48{ 49 return *__ptr == __SIMPLELOCK_LOCKED; 50} 51 52static __inline int 53__SIMPLELOCK_UNLOCKED_P(__cpu_simple_lock_t *__ptr) 54{ 55 return *__ptr == __SIMPLELOCK_UNLOCKED; 56} 57 58static __inline void 59__cpu_simple_lock_clear(__cpu_simple_lock_t *__ptr) 60{ 61 *__ptr = __SIMPLELOCK_UNLOCKED; 62} 63 64static __inline void 65__cpu_simple_lock_set(__cpu_simple_lock_t *__ptr) 66{ 67 *__ptr = __SIMPLELOCK_LOCKED; 68} 69 70static __inline void __cpu_simple_lock_init(__cpu_simple_lock_t *); 71static __inline void 72__cpu_simple_lock_init(__cpu_simple_lock_t *__alp) 73{ 74#ifdef _HARDKERNEL 75 __asm __volatile ("movl %0,%%r1;jsb Sunlock" 76 : /* No output */ 77 : "g"(__alp) 78 : "r1","cc","memory"); 79#else 80 __asm __volatile ("bbcci $0,%0,1f;1:" 81 : /* No output */ 82 : "m"(*__alp) 83 : "cc"); 84#endif 85} 86 87static __inline int __cpu_simple_lock_try(__cpu_simple_lock_t *); 88static __inline int 89__cpu_simple_lock_try(__cpu_simple_lock_t *__alp) 90{ 91 int ret; 92 93#ifdef _HARDKERNEL 94 __asm __volatile ("movl %1,%%r1;jsb Slocktry;movl %%r0,%0" 95 : "=&r"(ret) 96 : "g"(__alp) 97 : "r0","r1","cc","memory"); 98#else 99 __asm __volatile ("clrl %0;bbssi $0,%1,1f;incl %0;1:" 100 : "=&r"(ret) 101 : "m"(*__alp) 102 : "cc"); 103#endif 104 105 return ret; 106} 107 108static __inline void __cpu_simple_lock(__cpu_simple_lock_t *); 109static __inline void 110__cpu_simple_lock(__cpu_simple_lock_t *__alp) 111{ 112#if defined(_HARDKERNEL) && defined(MULTIPROCESSOR) 113 struct cpu_info * const __ci = curcpu(); 114 115 while (__cpu_simple_lock_try(__alp) == 0) { 116#define VAX_LOCK_CHECKS ((1 << IPI_SEND_CNCHAR) | (1 << IPI_DDB)) 117 if (__ci->ci_ipimsgs & VAX_LOCK_CHECKS) { 118 cpu_handle_ipi(); 119 } 120 } 121#else /* _HARDKERNEL && MULTIPROCESSOR */ 122 __asm __volatile ("1:bbssi $0,%0,1b" 123 : /* No outputs */ 124 : "m"(*__alp) 125 : "cc"); 126#endif /* _HARDKERNEL && MULTIPROCESSOR */ 127} 128 129static __inline void __cpu_simple_unlock(__cpu_simple_lock_t *); 130static __inline void 131__cpu_simple_unlock(__cpu_simple_lock_t *__alp) 132{ 133#ifdef _HARDKERNEL 134 __asm __volatile ("movl %0,%%r1;jsb Sunlock" 135 : /* No output */ 136 : "g"(__alp) 137 : "r1","cc","memory"); 138#else 139 __asm __volatile ("bbcci $0,%0,1f;1:" 140 : /* No output */ 141 : "m"(*__alp) 142 : "cc"); 143#endif 144} 145 146#if defined(MULTIPROCESSOR) 147/* 148 * On the Vax, interprocessor interrupts can come in at device priority 149 * level or lower. This can cause some problems while waiting for r/w 150 * spinlocks from a high'ish priority level: IPIs that come in will not 151 * be processed. This can lead to deadlock. 152 * 153 * This hook allows IPIs to be processed while a spinlock's interlock 154 * is released. 155 */ 156#define SPINLOCK_SPIN_HOOK \ 157do { \ 158 struct cpu_info * const __ci = curcpu(); \ 159 \ 160 if (__ci->ci_ipimsgs != 0) { \ 161 /* printf("CPU %lu has IPIs pending\n", \ 162 __ci->ci_cpuid); */ \ 163 cpu_handle_ipi(); \ 164 } \ 165} while (/*CONSTCOND*/0) 166#endif /* MULTIPROCESSOR */ 167 168static __inline void mb_read(void); 169static __inline void 170mb_read(void) 171{ 172} 173 174static __inline void mb_write(void); 175static __inline void 176mb_write(void) 177{ 178} 179#endif /* _VAX_LOCK_H_ */ 180