lock.h revision 1.24
1/* $NetBSD: lock.h,v 1.24 2007/02/26 01:33:41 christos 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#ifdef _KERNEL 37#ifdef _KERNEL_OPT 38#include "opt_multiprocessor.h" 39#include <machine/intr.h> 40#endif 41#include <machine/cpu.h> 42#endif 43 44static __inline void __cpu_simple_lock_init(__cpu_simple_lock_t *); 45static __inline void 46__cpu_simple_lock_init(__cpu_simple_lock_t *__alp) 47{ 48#ifdef _KERNEL 49 __asm volatile ("movl %0,%%r1;jsb Sunlock" 50 : /* No output */ 51 : "g"(__alp) 52 : "r1","cc","memory"); 53#else 54 __asm volatile ("bbcci $0,%0,1f;1:" 55 : /* No output */ 56 : "m"(*__alp) 57 : "cc"); 58#endif 59} 60 61static __inline int __cpu_simple_lock_try(__cpu_simple_lock_t *); 62static __inline int 63__cpu_simple_lock_try(__cpu_simple_lock_t *__alp) 64{ 65 int ret; 66 67#ifdef _KERNEL 68 __asm volatile ("movl %1,%%r1;jsb Slocktry;movl %%r0,%0" 69 : "=&r"(ret) 70 : "g"(__alp) 71 : "r0","r1","cc","memory"); 72#else 73 __asm volatile ("clrl %0;bbssi $0,%1,1f;incl %0;1:" 74 : "=&r"(ret) 75 : "m"(*__alp) 76 : "cc"); 77#endif 78 79 return ret; 80} 81 82#ifdef _KERNEL 83#define VAX_LOCK_CHECKS ((1 << IPI_SEND_CNCHAR) | (1 << IPI_DDB)) 84#define __cpu_simple_lock(__alp) \ 85do { \ 86 struct cpu_info *__ci = curcpu(); \ 87 \ 88 while (__cpu_simple_lock_try(__alp) == 0) { \ 89 int __s; \ 90 \ 91 if (__ci->ci_ipimsgs & VAX_LOCK_CHECKS) { \ 92 __s = splipi(); \ 93 cpu_handle_ipi(); \ 94 splx(__s); \ 95 } \ 96 } \ 97} while (/*CONSTCOND*/0) 98#else 99static __inline void __cpu_simple_lock(__cpu_simple_lock_t *); 100static __inline void 101__cpu_simple_lock(__cpu_simple_lock_t *__alp) 102{ 103 __asm volatile ("1:bbssi $0,%0,1b" 104 : /* No outputs */ 105 : "m"(*__alp) 106 : "cc"); 107} 108#endif /* _KERNEL */ 109 110#if 0 111static __inline void __cpu_simple_lock(__cpu_simple_lock_t *); 112static __inline void 113__cpu_simple_lock(__cpu_simple_lock_t *__alp) 114{ 115 struct cpu_info *ci = curcpu(); 116 117 while (__cpu_simple_lock_try(__alp) == 0) { 118 int s; 119 120 if (ci->ci_ipimsgs & IPI_SEND_CNCHAR) { 121 s = splipi(); 122 cpu_handle_ipi(); 123 splx(s); 124 } 125 } 126 127#if 0 128 __asm volatile ("movl %0,%%r1;jsb Slock" 129 : /* No output */ 130 : "g"(__alp) 131 : "r0","r1","cc","memory"); 132#endif 133#if 0 134 __asm volatile ("1:;bbssi $0, %0, 1b" 135 : /* No output */ 136 : "m"(*__alp)); 137#endif 138} 139#endif 140 141static __inline void __cpu_simple_unlock(__cpu_simple_lock_t *); 142static __inline void 143__cpu_simple_unlock(__cpu_simple_lock_t *__alp) 144{ 145#ifdef _KERNEL 146 __asm volatile ("movl %0,%%r1;jsb Sunlock" 147 : /* No output */ 148 : "g"(__alp) 149 : "r1","cc","memory"); 150#else 151 __asm volatile ("bbcci $0,%0,1f;1:" 152 : /* No output */ 153 : "m"(*__alp) 154 : "cc"); 155#endif 156} 157 158#if defined(MULTIPROCESSOR) 159/* 160 * On the Vax, interprocessor interrupts can come in at device priority 161 * level or lower. This can cause some problems while waiting for r/w 162 * spinlocks from a high'ish priority level: IPIs that come in will not 163 * be processed. This can lead to deadlock. 164 * 165 * This hook allows IPIs to be processed while a spinlock's interlock 166 * is released. 167 */ 168#define SPINLOCK_SPIN_HOOK \ 169do { \ 170 struct cpu_info *__ci = curcpu(); \ 171 int __s; \ 172 \ 173 if (__ci->ci_ipimsgs != 0) { \ 174 /* printf("CPU %lu has IPIs pending\n", \ 175 __ci->ci_cpuid); */ \ 176 __s = splipi(); \ 177 cpu_handle_ipi(); \ 178 splx(__s); \ 179 } \ 180} while (/*CONSTCOND*/0) 181#endif /* MULTIPROCESSOR */ 182 183static __inline void mb_read(void); 184static __inline void 185mb_read(void) 186{ 187} 188 189static __inline void mb_write(void); 190static __inline void 191mb_write(void) 192{ 193} 194#endif /* _VAX_LOCK_H_ */ 195