1 /* $OpenBSD: atomic.h,v 1.9 2012/11/19 15:18:06 pirofti Exp $ */ 2 /* $NetBSD: atomic.h,v 1.1 2003/04/26 18:39:37 fvdl Exp $ */ 3 4 /* 5 * Copyright 2002 (c) Wasabi Systems, Inc. 6 * All rights reserved. 7 * 8 * Written by Frank van der Linden for Wasabi Systems, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed for the NetBSD Project by 21 * Wasabi Systems, Inc. 22 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 23 * or promote products derived from this software without specific prior 24 * written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #ifndef _MACHINE_ATOMIC_H_ 40 #define _MACHINE_ATOMIC_H_ 41 42 /* 43 * Perform atomic operations on memory. Should be atomic with respect 44 * to interrupts and multiple processors. 45 * 46 * void atomic_setbits_int(volatile u_int *a, u_int mask) { *a |= mask; } 47 * void atomic_clearbits_int(volatile u_int *a, u_int mas) { *a &= ~mask; } 48 */ 49 50 #if defined(_KERNEL) && !defined(_LOCORE) 51 52 #ifdef MULTIPROCESSOR 53 #define LOCK "lock" 54 #else 55 #define LOCK 56 #endif 57 58 static __inline u_int64_t 59 x86_atomic_testset_u64(volatile u_int64_t *ptr, u_int64_t val) 60 { 61 __asm__ volatile ("xchgq %0,(%2)" :"=r" (val):"0" (val),"r" (ptr)); 62 return val; 63 } 64 65 static __inline u_int32_t 66 x86_atomic_testset_u32(volatile u_int32_t *ptr, u_int32_t val) 67 { 68 __asm__ volatile ("xchgl %0,(%2)" :"=r" (val):"0" (val),"r" (ptr)); 69 return val; 70 } 71 72 static __inline int32_t 73 x86_atomic_testset_i32(volatile int32_t *ptr, int32_t val) 74 { 75 __asm__ volatile ("xchgl %0,(%2)" :"=r" (val):"0" (val),"r" (ptr)); 76 return val; 77 } 78 79 80 81 static __inline void 82 x86_atomic_setbits_u32(volatile u_int32_t *ptr, u_int32_t bits) 83 { 84 __asm __volatile(LOCK " orl %1,%0" : "=m" (*ptr) : "ir" (bits)); 85 } 86 87 static __inline void 88 x86_atomic_clearbits_u32(volatile u_int32_t *ptr, u_int32_t bits) 89 { 90 __asm __volatile(LOCK " andl %1,%0" : "=m" (*ptr) : "ir" (~bits)); 91 } 92 93 static __inline int 94 x86_atomic_cas_int32(volatile int32_t *ptr, int32_t expect, int32_t set) 95 { 96 int res; 97 98 __asm volatile(LOCK " cmpxchgl %2, %1" : "=a" (res), "=m" (*ptr) 99 : "r" (set), "a" (expect), "m" (*ptr) : "memory"); 100 101 return (res); 102 } 103 104 static __inline u_long 105 x86_atomic_cas_ul(volatile u_long *ptr, u_long expect, u_long set) 106 { 107 u_long res; 108 109 __asm volatile(LOCK " cmpxchgq %2, %1" : "=a" (res), "=m" (*ptr) 110 : "r" (set), "a" (expect), "m" (*ptr) : "memory"); 111 112 return (res); 113 } 114 115 /* 116 * XXX XXX XXX 117 * theoretically 64bit cannot be used as 118 * an "i" and thus if we ever try to give 119 * these anything from the high dword there 120 * is an asm error pending 121 */ 122 static __inline void 123 x86_atomic_setbits_u64(volatile u_int64_t *ptr, u_int64_t bits) 124 { 125 __asm __volatile(LOCK " orq %1,%0" : "=m" (*ptr) : "ir" (bits)); 126 } 127 128 static __inline void 129 x86_atomic_clearbits_u64(volatile u_int64_t *ptr, u_int64_t bits) 130 { 131 __asm __volatile(LOCK " andq %1,%0" : "=m" (*ptr) : "ir" (~bits)); 132 } 133 134 #define x86_atomic_testset_ul x86_atomic_testset_u64 135 #define x86_atomic_testset_i x86_atomic_testset_i32 136 #define x86_atomic_setbits_ul x86_atomic_setbits_u64 137 #define x86_atomic_clearbits_ul x86_atomic_clearbits_u64 138 139 #define atomic_setbits_int x86_atomic_setbits_u32 140 #define atomic_clearbits_int x86_atomic_clearbits_u32 141 142 #undef LOCK 143 144 #endif /* defined(_KERNEL) && !defined(_LOCORE) */ 145 #endif /* _MACHINE_ATOMIC_H_ */ 146