1 /* $NetBSD: lock.h,v 1.12 2003/06/23 11:01:49 martin 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 #include "opt_multiprocessor.h" 38 #include <machine/cpu.h> 39 #endif 40 41 typedef __volatile int __cpu_simple_lock_t; 42 43 #define __SIMPLELOCK_LOCKED 1 44 #define __SIMPLELOCK_UNLOCKED 0 45 46 static __inline void 47 __cpu_simple_lock_init(__cpu_simple_lock_t *alp) 48 { 49 #ifdef _KERNEL 50 __asm__ __volatile ("movl %0,%%r1;jsb Sunlock" 51 : /* No output */ 52 : "g"(alp) 53 : "r1","cc","memory"); 54 #else 55 __asm__ __volatile ("bbcci $0,%0,1f;1:" 56 : /* No output */ 57 : "m"(*alp) 58 : "cc"); 59 #endif 60 } 61 62 static __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) \ 85 do { \ 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 (0) 98 #else 99 static __inline void 100 __cpu_simple_lock(__cpu_simple_lock_t *alp) 101 { 102 __asm__ __volatile ("1:bbssi $0,%0,1b" 103 : /* No outputs */ 104 : "m"(*alp) 105 : "cc"); 106 } 107 #endif /* _KERNEL */ 108 109 #if 0 110 static __inline void 111 __cpu_simple_lock(__cpu_simple_lock_t *alp) 112 { 113 struct cpu_info *ci = curcpu(); 114 115 while (__cpu_simple_lock_try(alp) == 0) { 116 int s; 117 118 if (ci->ci_ipimsgs & IPI_SEND_CNCHAR) { 119 s = splipi(); 120 cpu_handle_ipi(); 121 splx(s); 122 } 123 } 124 125 #if 0 126 __asm__ __volatile ("movl %0,%%r1;jsb Slock" 127 : /* No output */ 128 : "g"(alp) 129 : "r0","r1","cc","memory"); 130 #endif 131 #if 0 132 __asm__ __volatile ("1:;bbssi $0, %0, 1b" 133 : /* No output */ 134 : "m"(*alp)); 135 #endif 136 } 137 #endif 138 139 static __inline void 140 __cpu_simple_unlock(__cpu_simple_lock_t *alp) 141 { 142 #ifdef _KERNEL 143 __asm__ __volatile ("movl %0,%%r1;jsb Sunlock" 144 : /* No output */ 145 : "g"(alp) 146 : "r1","cc","memory"); 147 #else 148 __asm__ __volatile ("bbcci $0,%0,1f;1:" 149 : /* No output */ 150 : "m"(*alp) 151 : "cc"); 152 #endif 153 } 154 155 #if defined(MULTIPROCESSOR) 156 /* 157 * On the Vax, interprocessor interrupts can come in at device priority 158 * level or lower. This can cause some problems while waiting for r/w 159 * spinlocks from a high'ish priority level: IPIs that come in will not 160 * be processed. This can lead to deadlock. 161 * 162 * This hook allows IPIs to be processed while a spinlock's interlock 163 * is released. 164 */ 165 #define SPINLOCK_SPIN_HOOK \ 166 do { \ 167 struct cpu_info *__ci = curcpu(); \ 168 int __s; \ 169 \ 170 if (__ci->ci_ipimsgs != 0) { \ 171 /* printf("CPU %lu has IPIs pending\n", \ 172 __ci->ci_cpuid); */ \ 173 __s = splipi(); \ 174 cpu_handle_ipi(); \ 175 splx(__s); \ 176 } \ 177 } while (0) 178 #endif /* MULTIPROCESSOR */ 179 #endif /* _VAX_LOCK_H_ */ 180