| 1 | #ifndef _URCU_UATOMIC_GENERIC_H |
| 2 | #define _URCU_UATOMIC_GENERIC_H |
| 3 | |
| 4 | /* |
| 5 | * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. |
| 6 | * Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved. |
| 7 | * Copyright (c) 1999-2004 Hewlett-Packard Development Company, L.P. |
| 8 | * Copyright (c) 2009 Mathieu Desnoyers |
| 9 | * Copyright (c) 2010 Paolo Bonzini |
| 10 | * |
| 11 | * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED |
| 12 | * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. |
| 13 | * |
| 14 | * Permission is hereby granted to use or copy this program |
| 15 | * for any purpose, provided the above notices are retained on all copies. |
| 16 | * Permission to modify the code and to distribute modified code is granted, |
| 17 | * provided the above notices are retained, and a notice that the code was |
| 18 | * modified is included with the above copyright notice. |
| 19 | * |
| 20 | * Code inspired from libuatomic_ops-1.2, inherited in part from the |
| 21 | * Boehm-Demers-Weiser conservative garbage collector. |
| 22 | */ |
| 23 | |
| 24 | #include <urcu/compiler.h> |
| 25 | #include <urcu/system.h> |
| 26 | |
| 27 | #ifdef __cplusplus |
| 28 | extern "C" { |
| 29 | #endif |
| 30 | |
| 31 | #ifndef BITS_PER_LONG |
| 32 | #define BITS_PER_LONG (__SIZEOF_LONG__ * 8) |
| 33 | #endif |
| 34 | |
| 35 | #ifndef uatomic_set |
| 36 | #define uatomic_set(addr, v) STORE_SHARED(*(addr), (v)) |
| 37 | #endif |
| 38 | |
| 39 | #ifndef uatomic_read |
| 40 | #define uatomic_read(addr) LOAD_SHARED(*(addr)) |
| 41 | #endif |
| 42 | |
| 43 | #if !defined __OPTIMIZE__ || defined UATOMIC_NO_LINK_ERROR |
| 44 | static inline __attribute__((always_inline)) |
| 45 | void _uatomic_link_error() |
| 46 | { |
| 47 | #ifdef ILLEGAL_INSTR |
| 48 | /* generate an illegal instruction. Cannot catch this with linker tricks |
| 49 | * when optimizations are disabled. */ |
| 50 | __asm__ __volatile__(ILLEGAL_INSTR); |
| 51 | #else |
| 52 | __builtin_trap (); |
| 53 | #endif |
| 54 | } |
| 55 | |
| 56 | #else /* #if !defined __OPTIMIZE__ || defined UATOMIC_NO_LINK_ERROR */ |
| 57 | extern void _uatomic_link_error (); |
| 58 | #endif /* #else #if !defined __OPTIMIZE__ || defined UATOMIC_NO_LINK_ERROR */ |
| 59 | |
| 60 | /* cmpxchg */ |
| 61 | |
| 62 | #ifndef uatomic_cmpxchg |
| 63 | static inline __attribute__((always_inline)) |
| 64 | unsigned long _uatomic_cmpxchg(void *addr, unsigned long old, |
| 65 | unsigned long _new, int len) |
| 66 | { |
| 67 | switch (len) { |
| 68 | case 4: |
| 69 | return __sync_val_compare_and_swap_4(addr, old, _new); |
| 70 | #if (BITS_PER_LONG == 64) |
| 71 | case 8: |
| 72 | return __sync_val_compare_and_swap_8(addr, old, _new); |
| 73 | #endif |
| 74 | } |
| 75 | _uatomic_link_error(); |
| 76 | return 0; |
| 77 | } |
| 78 | |
| 79 | |
| 80 | #define uatomic_cmpxchg(addr, old, _new) \ |
| 81 | ((__typeof__(*(addr))) _uatomic_cmpxchg((addr), (unsigned long)(old),\ |
| 82 | (unsigned long)(_new), \ |
| 83 | sizeof(*(addr)))) |
| 84 | |
| 85 | |
| 86 | /* uatomic_add_return */ |
| 87 | |
| 88 | #ifndef uatomic_add_return |
| 89 | static inline __attribute__((always_inline)) |
| 90 | unsigned long _uatomic_add_return(void *addr, unsigned long val, |
| 91 | int len) |
| 92 | { |
| 93 | switch (len) { |
| 94 | case 4: |
| 95 | return __sync_add_and_fetch_4(addr, val); |
| 96 | #if (BITS_PER_LONG == 64) |
| 97 | case 8: |
| 98 | return __sync_add_and_fetch_8(addr, val); |
| 99 | #endif |
| 100 | } |
| 101 | _uatomic_link_error(); |
| 102 | return 0; |
| 103 | } |
| 104 | |
| 105 | |
| 106 | #define uatomic_add_return(addr, v) \ |
| 107 | ((__typeof__(*(addr))) _uatomic_add_return((addr), \ |
| 108 | (unsigned long)(v), \ |
| 109 | sizeof(*(addr)))) |
| 110 | #endif /* #ifndef uatomic_add_return */ |
| 111 | |
| 112 | #ifndef uatomic_xchg |
| 113 | /* xchg */ |
| 114 | |
| 115 | static inline __attribute__((always_inline)) |
| 116 | unsigned long _uatomic_exchange(void *addr, unsigned long val, int len) |
| 117 | { |
| 118 | switch (len) { |
| 119 | case 4: |
| 120 | { |
| 121 | unsigned int old; |
| 122 | |
| 123 | do { |
| 124 | old = uatomic_read((unsigned int *)addr); |
| 125 | while (!__sync_bool_compare_and_swap_4(addr, old, val)); |
| 126 | |
| 127 | } return old; |
| 128 | } |
| 129 | #if (BITS_PER_LONG == 64) |
| 130 | case 8: |
| 131 | { |
| 132 | unsigned long old; |
| 133 | |
| 134 | do { |
| 135 | old = uatomic_read((unsigned long *)addr); |
| 136 | } while (!__sync_bool_compare_and_swap_8(addr, old, val)); |
| 137 | |
| 138 | return old; |
| 139 | } |
| 140 | #endif |
| 141 | } |
| 142 | _uatomic_link_error(); |
| 143 | return 0; |
| 144 | } |
| 145 | |
| 146 | #define uatomic_xchg(addr, v) \ |
| 147 | ((__typeof__(*(addr))) _uatomic_exchange((addr), (unsigned long)(v), \ |
| 148 | sizeof(*(addr)))) |
| 149 | #endif /* #ifndef uatomic_xchg */ |
| 150 | |
| 151 | #else /* #ifndef uatomic_cmpxchg */ |
| 152 | |
| 153 | #ifndef uatomic_add_return |
| 154 | /* uatomic_add_return */ |
| 155 | |
| 156 | static inline __attribute__((always_inline)) |
| 157 | unsigned long _uatomic_add_return(void *addr, unsigned long val, int len) |
| 158 | { |
| 159 | switch (len) { |
| 160 | case 4: |
| 161 | { |
| 162 | unsigned int old, oldt; |
| 163 | |
| 164 | oldt = uatomic_read((unsigned int *)addr); |
| 165 | do { |
| 166 | old = oldt; |
| 167 | oldt = _uatomic_cmpxchg(addr, old, old + val, 4); |
| 168 | } while (oldt != old); |
| 169 | |
| 170 | return old + val; |
| 171 | } |
| 172 | #if (BITS_PER_LONG == 64) |
| 173 | case 8: |
| 174 | { |
| 175 | unsigned long old, oldt; |
| 176 | |
| 177 | oldt = uatomic_read((unsigned long *)addr); |
| 178 | do { |
| 179 | old = oldt; |
| 180 | oldt = _uatomic_cmpxchg(addr, old, old + val, 8); |
| 181 | } while (oldt != old); |
| 182 | |
| 183 | return old + val; |
| 184 | } |
| 185 | #endif |
| 186 | } |
| 187 | _uatomic_link_error(); |
| 188 | return 0; |
| 189 | } |
| 190 | |
| 191 | #define uatomic_add_return(addr, v) \ |
| 192 | ((__typeof__(*(addr))) _uatomic_add_return((addr), \ |
| 193 | (unsigned long)(v), \ |
| 194 | sizeof(*(addr)))) |
| 195 | #endif /* #ifndef uatomic_add_return */ |
| 196 | |
| 197 | #ifndef uatomic_xchg |
| 198 | /* xchg */ |
| 199 | |
| 200 | static inline __attribute__((always_inline)) |
| 201 | unsigned long _uatomic_exchange(void *addr, unsigned long val, int len) |
| 202 | { |
| 203 | switch (len) { |
| 204 | case 4: |
| 205 | { |
| 206 | unsigned int old, oldt; |
| 207 | |
| 208 | oldt = uatomic_read((unsigned int *)addr); |
| 209 | do { |
| 210 | old = oldt; |
| 211 | oldt = _uatomic_cmpxchg(addr, old, val, 4); |
| 212 | } while (oldt != old); |
| 213 | |
| 214 | return old; |
| 215 | } |
| 216 | #if (BITS_PER_LONG == 64) |
| 217 | case 8: |
| 218 | { |
| 219 | unsigned long old, oldt; |
| 220 | |
| 221 | oldt = uatomic_read((unsigned long *)addr); |
| 222 | do { |
| 223 | old = oldt; |
| 224 | oldt = _uatomic_cmpxchg(addr, old, val, 8); |
| 225 | } while (oldt != old); |
| 226 | |
| 227 | return old; |
| 228 | } |
| 229 | #endif |
| 230 | } |
| 231 | _uatomic_link_error(); |
| 232 | return 0; |
| 233 | } |
| 234 | |
| 235 | #define uatomic_xchg(addr, v) \ |
| 236 | ((__typeof__(*(addr))) _uatomic_exchange((addr), (unsigned long)(v), \ |
| 237 | sizeof(*(addr)))) |
| 238 | #endif /* #ifndef uatomic_xchg */ |
| 239 | |
| 240 | #endif /* #else #ifndef uatomic_cmpxchg */ |
| 241 | |
| 242 | /* uatomic_sub_return, uatomic_add, uatomic_sub, uatomic_inc, uatomic_dec */ |
| 243 | |
| 244 | #ifndef uatomic_add |
| 245 | #define uatomic_add(addr, v) (void)uatomic_add_return((addr), (v)) |
| 246 | #endif |
| 247 | |
| 248 | #define uatomic_sub_return(addr, v) uatomic_add_return((addr), -(v)) |
| 249 | #define uatomic_sub(addr, v) uatomic_add((addr), -(v)) |
| 250 | |
| 251 | #ifndef uatomic_inc |
| 252 | #define uatomic_inc(addr) uatomic_add((addr), 1) |
| 253 | #endif |
| 254 | |
| 255 | #ifndef uatomic_dec |
| 256 | #define uatomic_dec(addr) uatomic_add((addr), -1) |
| 257 | #endif |
| 258 | |
| 259 | #ifdef __cplusplus |
| 260 | } |
| 261 | #endif |
| 262 | |
| 263 | #endif /* _URCU_UATOMIC_GENERIC_H */ |