1 /* $NetBSD: lock.h,v 1.29 2009/01/14 23:20:34 pooka 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 46 static __inline int 47 __SIMPLELOCK_LOCKED_P(__cpu_simple_lock_t *__ptr) 48 { 49 return *__ptr == __SIMPLELOCK_LOCKED; 50 } 51 52 static __inline int 53 __SIMPLELOCK_UNLOCKED_P(__cpu_simple_lock_t *__ptr) 54 { 55 return *__ptr == __SIMPLELOCK_UNLOCKED; 56 } 57 58 static __inline void 59 __cpu_simple_lock_clear(__cpu_simple_lock_t *__ptr) 60 { 61 *__ptr = __SIMPLELOCK_UNLOCKED; 62 } 63 64 static __inline void 65 __cpu_simple_lock_set(__cpu_simple_lock_t *__ptr) 66 { 67 *__ptr = __SIMPLELOCK_LOCKED; 68 } 69 70 static __inline void __cpu_simple_lock_init(__cpu_simple_lock_t *); 71 static __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 87 static __inline int __cpu_simple_lock_try(__cpu_simple_lock_t *); 88 static __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 } 107 108 static __inline void __cpu_simple_lock(__cpu_simple_lock_t *); 109 static __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 } 128 129 static __inline void __cpu_simple_unlock(__cpu_simple_lock_t *); 130 static __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 \ 157 do { \ 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 */ 167 168 static __inline void mb_read(void); 169 static __inline void 170 mb_read(void) 171 { 172 } 173 174 static __inline void mb_write(void); 175 static __inline void 176 mb_write(void) 177 { 178 } 179 #endif /* _VAX_LOCK_H_ */ 180