1 /* $NetBSD: lock.h,v 1.20 2005/12/24 23:24:07 perry 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 44 static inline void 45 __cpu_simple_lock_init(__cpu_simple_lock_t *alp) 46 { 47 #ifdef _KERNEL 48 __asm volatile ("movl %0,%%r1;jsb Sunlock" 49 : /* No output */ 50 : "g"(alp) 51 : "r1","cc","memory"); 52 #else 53 __asm volatile ("bbcci $0,%0,1f;1:" 54 : /* No output */ 55 : "m"(*alp) 56 : "cc"); 57 #endif 58 } 59 60 static inline int 61 __cpu_simple_lock_try(__cpu_simple_lock_t *alp) 62 { 63 int ret; 64 65 #ifdef _KERNEL 66 __asm volatile ("movl %1,%%r1;jsb Slocktry;movl %%r0,%0" 67 : "=&r"(ret) 68 : "g"(alp) 69 : "r0","r1","cc","memory"); 70 #else 71 __asm volatile ("clrl %0;bbssi $0,%1,1f;incl %0;1:" 72 : "=&r"(ret) 73 : "m"(*alp) 74 : "cc"); 75 #endif 76 77 return ret; 78 } 79 80 #ifdef _KERNEL 81 #define VAX_LOCK_CHECKS ((1 << IPI_SEND_CNCHAR) | (1 << IPI_DDB)) 82 #define __cpu_simple_lock(alp) \ 83 do { \ 84 struct cpu_info *__ci = curcpu(); \ 85 \ 86 while (__cpu_simple_lock_try(alp) == 0) { \ 87 int ___s; \ 88 \ 89 if (__ci->ci_ipimsgs & VAX_LOCK_CHECKS) { \ 90 ___s = splipi(); \ 91 cpu_handle_ipi(); \ 92 splx(___s); \ 93 } \ 94 } \ 95 } while (0) 96 #else 97 static inline void 98 __cpu_simple_lock(__cpu_simple_lock_t *alp) 99 { 100 __asm volatile ("1:bbssi $0,%0,1b" 101 : /* No outputs */ 102 : "m"(*alp) 103 : "cc"); 104 } 105 #endif /* _KERNEL */ 106 107 #if 0 108 static inline void 109 __cpu_simple_lock(__cpu_simple_lock_t *alp) 110 { 111 struct cpu_info *ci = curcpu(); 112 113 while (__cpu_simple_lock_try(alp) == 0) { 114 int s; 115 116 if (ci->ci_ipimsgs & IPI_SEND_CNCHAR) { 117 s = splipi(); 118 cpu_handle_ipi(); 119 splx(s); 120 } 121 } 122 123 #if 0 124 __asm volatile ("movl %0,%%r1;jsb Slock" 125 : /* No output */ 126 : "g"(alp) 127 : "r0","r1","cc","memory"); 128 #endif 129 #if 0 130 __asm volatile ("1:;bbssi $0, %0, 1b" 131 : /* No output */ 132 : "m"(*alp)); 133 #endif 134 } 135 #endif 136 137 static inline void 138 __cpu_simple_unlock(__cpu_simple_lock_t *alp) 139 { 140 #ifdef _KERNEL 141 __asm volatile ("movl %0,%%r1;jsb Sunlock" 142 : /* No output */ 143 : "g"(alp) 144 : "r1","cc","memory"); 145 #else 146 __asm volatile ("bbcci $0,%0,1f;1:" 147 : /* No output */ 148 : "m"(*alp) 149 : "cc"); 150 #endif 151 } 152 153 #if defined(MULTIPROCESSOR) 154 /* 155 * On the Vax, interprocessor interrupts can come in at device priority 156 * level or lower. This can cause some problems while waiting for r/w 157 * spinlocks from a high'ish priority level: IPIs that come in will not 158 * be processed. This can lead to deadlock. 159 * 160 * This hook allows IPIs to be processed while a spinlock's interlock 161 * is released. 162 */ 163 #define SPINLOCK_SPIN_HOOK \ 164 do { \ 165 struct cpu_info *__ci = curcpu(); \ 166 int ___s; \ 167 \ 168 if (__ci->ci_ipimsgs != 0) { \ 169 /* printf("CPU %lu has IPIs pending\n", \ 170 __ci->ci_cpuid); */ \ 171 ___s = splipi(); \ 172 cpu_handle_ipi(); \ 173 splx(___s); \ 174 } \ 175 } while (0) 176 #endif /* MULTIPROCESSOR */ 177 #endif /* _VAX_LOCK_H_ */ 178