atomic_init_testset.c revision 1.10
1 /* $NetBSD: atomic_init_testset.c,v 1.10 2014/01/27 18:03:44 matt Exp $ */ 2 3 /*- 4 * Copyright (c) 2008 The NetBSD Foundation, Inc. 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * libc glue for atomic operations where the hardware does not provide 31 * compare-and-swap. It's assumed that this will only be used on 32-bit 32 * platforms. 33 * 34 * This should be compiled with '-fno-reorder-blocks -fomit-frame-pointer' 35 * if using gcc. 36 */ 37 38 #include <sys/cdefs.h> 39 __RCSID("$NetBSD: atomic_init_testset.c,v 1.10 2014/01/27 18:03:44 matt Exp $"); 40 41 #include "atomic_op_namespace.h" 42 43 #include <sys/types.h> 44 #include <sys/atomic.h> 45 #include <sys/lock.h> 46 #include <sys/ras.h> 47 #include <sys/sysctl.h> 48 49 #include <string.h> 50 51 #define I2 __SIMPLELOCK_UNLOCKED, __SIMPLELOCK_UNLOCKED, 52 #define I16 I2 I2 I2 I2 I2 I2 I2 I2 53 #define I128 I16 I16 I16 I16 I16 I16 I16 I16 54 55 static __cpu_simple_lock_t atomic_locks[128] = { I128 }; 56 57 #ifdef __HAVE_ASM_ATOMIC_CAS_UP 58 extern uint32_t _atomic_cas_up(volatile uint32_t *, uint32_t, uint32_t); 59 #else 60 static uint32_t _atomic_cas_up(volatile uint32_t *, uint32_t, uint32_t); 61 #endif 62 static uint32_t (*_atomic_cas_fn)(volatile uint32_t *, uint32_t, uint32_t) = 63 _atomic_cas_up; 64 RAS_DECL(_atomic_cas); 65 66 #ifdef __HAVE_ASM_ATOMIC_CAS_16_UP 67 extern uint16_t _atomic_cas_16_up(volatile uint16_t *, uint16_t, uint16_t); 68 #else 69 static uint16_t _atomic_cas_16_up(volatile uint16_t *, uint16_t, uint16_t); 70 #endif 71 static uint16_t (*_atomic_cas_16_fn)(volatile uint16_t *, uint16_t, uint16_t) = 72 _atomic_cas_16_up; 73 RAS_DECL(_atomic_cas_16); 74 75 #ifdef __HAVE_ASM_ATOMIC_CAS_8_UP 76 extern uint8_t _atomic_cas_8_up(volatile uint8_t *, uint8_t, uint8_t); 77 #else 78 static uint8_t _atomic_cas_8_up(volatile uint8_t *, uint8_t, uint8_t); 79 #endif 80 static uint8_t (*_atomic_cas_8_fn)(volatile uint8_t *, uint8_t, uint8_t) = 81 _atomic_cas_8_up; 82 RAS_DECL(_atomic_cas_8); 83 84 void __libc_atomic_init(void) __attribute__ ((visibility("hidden"))); 85 86 #ifndef __HAVE_ASM_ATOMIC_CAS_UP 87 static uint32_t 88 _atomic_cas_up(volatile uint32_t *ptr, uint32_t old, uint32_t new) 89 { 90 uint32_t ret; 91 92 RAS_START(_atomic_cas); 93 ret = *ptr; 94 if (__predict_false(ret != old)) { 95 return ret; 96 } 97 *ptr = new; 98 RAS_END(_atomic_cas); 99 100 return ret; 101 } 102 #endif 103 104 #ifndef __HAVE_ASM_ATOMIC_CAS_16_UP 105 static uint16_t 106 _atomic_cas_up_16(volatile uint16_t *ptr, uint16_t old, uint16_t new) 107 { 108 uint16_t ret; 109 110 RAS_START(_atomic_cas_16); 111 ret = *ptr; 112 if (__predict_false(ret != old)) { 113 return ret; 114 } 115 *ptr = new; 116 RAS_END(_atomic_cas_16); 117 118 return ret; 119 } 120 #endif 121 122 #ifndef __HAVE_ASM_ATOMIC_CAS_UP 123 static uint8_t 124 _atomic_cas_up(volatile uint8_t *ptr, uint8_t old, uint8_t new) 125 { 126 uint8_t ret; 127 128 RAS_START(_atomic_cas_8); 129 ret = *ptr; 130 if (__predict_false(ret != old)) { 131 return ret; 132 } 133 *ptr = new; 134 RAS_END(_atomic_cas_16); 135 136 return ret; 137 } 138 #endif 139 140 static uint32_t 141 _atomic_cas_mp(volatile uint32_t *ptr, uint32_t old, uint32_t new) 142 { 143 __cpu_simple_lock_t *lock; 144 uint32_t ret; 145 146 lock = &atomic_locks[((uintptr_t)ptr >> 3) & 127]; 147 __cpu_simple_lock(lock); 148 ret = *ptr; 149 if (__predict_true(ret == old)) { 150 *ptr = new; 151 } 152 __cpu_simple_unlock(lock); 153 154 return ret; 155 } 156 157 uint32_t 158 _atomic_cas_32(volatile uint32_t *ptr, uint32_t old, uint32_t new) 159 { 160 161 return (*_atomic_cas_fn)(ptr, old, new); 162 } 163 164 uint16_t _atomic_cas_16(volatile uint16_t *, uint16_t, uint16_t); 165 166 uint16_t 167 _atomic_cas_16(volatile uint16_t *ptr, uint16_t old, uint16_t new) 168 { 169 170 return (*_atomic_cas_16_fn)(ptr, old, new); 171 } 172 173 uint8_t _atomic_cas_8(volatile uint8_t *, uint8_t, uint8_t); 174 175 uint8_t 176 _atomic_cas_8(volatile uint8_t *ptr, uint8_t old, uint8_t new) 177 { 178 179 return (*_atomic_cas_8_fn)(ptr, old, new); 180 } 181 182 void __section(".text.startup") 183 __libc_atomic_init(void) 184 { 185 int ncpu, mib[2]; 186 size_t len; 187 188 _atomic_cas_fn = _atomic_cas_mp; 189 190 mib[0] = CTL_HW; 191 mib[1] = HW_NCPU; 192 len = sizeof(ncpu); 193 if (sysctl(mib, 2, &ncpu, &len, NULL, 0) == -1) 194 return; 195 if (ncpu > 1) 196 return; 197 if (rasctl(RAS_ADDR(_atomic_cas), RAS_SIZE(_atomic_cas), 198 RAS_INSTALL) == 0) { 199 _atomic_cas_fn = _atomic_cas_up; 200 return; 201 } 202 203 if (rasctl(RAS_ADDR(_atomic_cas_16), RAS_SIZE(_atomic_cas_16), 204 RAS_INSTALL) == 0) { 205 _atomic_cas_16_fn = _atomic_cas_16_up; 206 return; 207 } 208 209 if (rasctl(RAS_ADDR(_atomic_cas_8), RAS_SIZE(_atomic_cas_8), 210 RAS_INSTALL) == 0) { 211 _atomic_cas_8_fn = _atomic_cas_8_up; 212 return; 213 } 214 } 215 216 #undef atomic_cas_32 217 #undef atomic_cas_uint 218 #undef atomic_cas_ulong 219 #undef atomic_cas_ptr 220 #undef atomic_cas_32_ni 221 #undef atomic_cas_uint_ni 222 #undef atomic_cas_ulong_ni 223 #undef atomic_cas_ptr_ni 224 225 atomic_op_alias(atomic_cas_32,_atomic_cas_32) 226 atomic_op_alias(atomic_cas_uint,_atomic_cas_32) 227 __strong_alias(_atomic_cas_uint,_atomic_cas_32) 228 atomic_op_alias(atomic_cas_ulong,_atomic_cas_32) 229 __strong_alias(_atomic_cas_ulong,_atomic_cas_32) 230 atomic_op_alias(atomic_cas_ptr,_atomic_cas_32) 231 __strong_alias(_atomic_cas_ptr,_atomic_cas_32) 232 233 atomic_op_alias(atomic_cas_32_ni,_atomic_cas_32) 234 __strong_alias(_atomic_cas_32_ni,_atomic_cas_32) 235 atomic_op_alias(atomic_cas_uint_ni,_atomic_cas_32) 236 __strong_alias(_atomic_cas_uint_ni,_atomic_cas_32) 237 atomic_op_alias(atomic_cas_ulong_ni,_atomic_cas_32) 238 __strong_alias(_atomic_cas_ulong_ni,_atomic_cas_32) 239 atomic_op_alias(atomic_cas_ptr_ni,_atomic_cas_32) 240 __strong_alias(_atomic_cas_ptr_ni,_atomic_cas_32) 241 242 __strong_alias(__sync_val_compare_and_swap_4,_atomic_cas_32) 243 __strong_alias(__sync_val_compare_and_swap_2,_atomic_cas_16) 244 __strong_alias(__sync_val_compare_and_swap_1,_atomic_cas_8) 245
Indexes created Tue Sep 30 10:09:55 GMT 2025