H. Peter Anvin | 1965aae | 2008-10-22 22:26:29 -0700 | [diff] [blame] | 1 | #ifndef _ASM_X86_BITOPS_H |
| 2 | #define _ASM_X86_BITOPS_H |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 3 | |
| 4 | /* |
| 5 | * Copyright 1992, Linus Torvalds. |
Andi Kleen | c8399943 | 2009-01-12 23:01:15 +0100 | [diff] [blame] | 6 | * |
| 7 | * Note: inlines with more than a single statement should be marked |
| 8 | * __always_inline to avoid problems with older gcc's inlining heuristics. |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 9 | */ |
| 10 | |
| 11 | #ifndef _LINUX_BITOPS_H |
| 12 | #error only <linux/bitops.h> can be included directly |
| 13 | #endif |
| 14 | |
| 15 | #include <linux/compiler.h> |
| 16 | #include <asm/alternative.h> |
| 17 | |
| 18 | /* |
| 19 | * These have to be done with inline assembly: that way the bit-setting |
| 20 | * is guaranteed to be atomic. All bit operations return 0 if the bit |
| 21 | * was cleared before the operation and != 0 if it was not. |
| 22 | * |
| 23 | * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). |
| 24 | */ |
| 25 | |
| 26 | #if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 1) |
| 27 | /* Technically wrong, but this avoids compilation errors on some gcc |
| 28 | versions. */ |
Linus Torvalds | 1a750e0 | 2008-06-18 21:03:26 -0700 | [diff] [blame] | 29 | #define BITOP_ADDR(x) "=m" (*(volatile long *) (x)) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 30 | #else |
Linus Torvalds | 1a750e0 | 2008-06-18 21:03:26 -0700 | [diff] [blame] | 31 | #define BITOP_ADDR(x) "+m" (*(volatile long *) (x)) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 32 | #endif |
| 33 | |
Ingo Molnar | 7dbceaf | 2008-06-20 07:28:24 +0200 | [diff] [blame] | 34 | #define ADDR BITOP_ADDR(addr) |
Linus Torvalds | 1a750e0 | 2008-06-18 21:03:26 -0700 | [diff] [blame] | 35 | |
| 36 | /* |
| 37 | * We do the locked ops that don't return the old value as |
| 38 | * a mask operation on a byte. |
| 39 | */ |
Ingo Molnar | 7dbceaf | 2008-06-20 07:28:24 +0200 | [diff] [blame] | 40 | #define IS_IMMEDIATE(nr) (__builtin_constant_p(nr)) |
| 41 | #define CONST_MASK_ADDR(nr, addr) BITOP_ADDR((void *)(addr) + ((nr)>>3)) |
| 42 | #define CONST_MASK(nr) (1 << ((nr) & 7)) |
Linus Torvalds | 1a750e0 | 2008-06-18 21:03:26 -0700 | [diff] [blame] | 43 | |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 44 | /** |
| 45 | * set_bit - Atomically set a bit in memory |
| 46 | * @nr: the bit to set |
| 47 | * @addr: the address to start counting from |
| 48 | * |
| 49 | * This function is atomic and may not be reordered. See __set_bit() |
| 50 | * if you do not require the atomic guarantees. |
| 51 | * |
| 52 | * Note: there are no guarantees that this function will not be reordered |
| 53 | * on non x86 architectures, so if you are writing portable code, |
| 54 | * make sure not to rely on its reordering guarantees. |
| 55 | * |
| 56 | * Note that @nr may be almost arbitrarily large; this function is not |
| 57 | * restricted to acting on a single-word quantity. |
| 58 | */ |
Andi Kleen | c8399943 | 2009-01-12 23:01:15 +0100 | [diff] [blame] | 59 | static __always_inline void |
| 60 | set_bit(unsigned int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 61 | { |
Ingo Molnar | 7dbceaf | 2008-06-20 07:28:24 +0200 | [diff] [blame] | 62 | if (IS_IMMEDIATE(nr)) { |
| 63 | asm volatile(LOCK_PREFIX "orb %1,%0" |
| 64 | : CONST_MASK_ADDR(nr, addr) |
Ingo Molnar | 437a0a5 | 2008-06-20 21:50:20 +0200 | [diff] [blame] | 65 | : "iq" ((u8)CONST_MASK(nr)) |
Ingo Molnar | 7dbceaf | 2008-06-20 07:28:24 +0200 | [diff] [blame] | 66 | : "memory"); |
| 67 | } else { |
| 68 | asm volatile(LOCK_PREFIX "bts %1,%0" |
| 69 | : BITOP_ADDR(addr) : "Ir" (nr) : "memory"); |
| 70 | } |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 71 | } |
| 72 | |
| 73 | /** |
| 74 | * __set_bit - Set a bit in memory |
| 75 | * @nr: the bit to set |
| 76 | * @addr: the address to start counting from |
| 77 | * |
| 78 | * Unlike set_bit(), this function is non-atomic and may be reordered. |
| 79 | * If it's called on the same region of memory simultaneously, the effect |
| 80 | * may be that only one operation succeeds. |
| 81 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 82 | static inline void __set_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 83 | { |
Joe Perches | f19dcf4 | 2008-03-23 01:03:07 -0700 | [diff] [blame] | 84 | asm volatile("bts %1,%0" : ADDR : "Ir" (nr) : "memory"); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 85 | } |
| 86 | |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 87 | /** |
| 88 | * clear_bit - Clears a bit in memory |
| 89 | * @nr: Bit to clear |
| 90 | * @addr: Address to start counting from |
| 91 | * |
| 92 | * clear_bit() is atomic and may not be reordered. However, it does |
| 93 | * not contain a memory barrier, so if it is used for locking purposes, |
| 94 | * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() |
| 95 | * in order to ensure changes are visible on other processors. |
| 96 | */ |
Andi Kleen | c8399943 | 2009-01-12 23:01:15 +0100 | [diff] [blame] | 97 | static __always_inline void |
| 98 | clear_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 99 | { |
Ingo Molnar | 7dbceaf | 2008-06-20 07:28:24 +0200 | [diff] [blame] | 100 | if (IS_IMMEDIATE(nr)) { |
| 101 | asm volatile(LOCK_PREFIX "andb %1,%0" |
| 102 | : CONST_MASK_ADDR(nr, addr) |
Ingo Molnar | 437a0a5 | 2008-06-20 21:50:20 +0200 | [diff] [blame] | 103 | : "iq" ((u8)~CONST_MASK(nr))); |
Ingo Molnar | 7dbceaf | 2008-06-20 07:28:24 +0200 | [diff] [blame] | 104 | } else { |
| 105 | asm volatile(LOCK_PREFIX "btr %1,%0" |
| 106 | : BITOP_ADDR(addr) |
| 107 | : "Ir" (nr)); |
| 108 | } |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 109 | } |
| 110 | |
| 111 | /* |
| 112 | * clear_bit_unlock - Clears a bit in memory |
| 113 | * @nr: Bit to clear |
| 114 | * @addr: Address to start counting from |
| 115 | * |
| 116 | * clear_bit() is atomic and implies release semantics before the memory |
| 117 | * operation. It can be used for an unlock. |
| 118 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 119 | static inline void clear_bit_unlock(unsigned nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 120 | { |
| 121 | barrier(); |
| 122 | clear_bit(nr, addr); |
| 123 | } |
| 124 | |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 125 | static inline void __clear_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 126 | { |
Simon Holm Thøgersen | eb2b4e6 | 2008-05-05 15:45:28 +0200 | [diff] [blame] | 127 | asm volatile("btr %1,%0" : ADDR : "Ir" (nr)); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 128 | } |
| 129 | |
| 130 | /* |
| 131 | * __clear_bit_unlock - Clears a bit in memory |
| 132 | * @nr: Bit to clear |
| 133 | * @addr: Address to start counting from |
| 134 | * |
| 135 | * __clear_bit() is non-atomic and implies release semantics before the memory |
| 136 | * operation. It can be used for an unlock if no other CPUs can concurrently |
| 137 | * modify other bits in the word. |
| 138 | * |
| 139 | * No memory barrier is required here, because x86 cannot reorder stores past |
| 140 | * older loads. Same principle as spin_unlock. |
| 141 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 142 | static inline void __clear_bit_unlock(unsigned nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 143 | { |
| 144 | barrier(); |
| 145 | __clear_bit(nr, addr); |
| 146 | } |
| 147 | |
| 148 | #define smp_mb__before_clear_bit() barrier() |
| 149 | #define smp_mb__after_clear_bit() barrier() |
| 150 | |
| 151 | /** |
| 152 | * __change_bit - Toggle a bit in memory |
| 153 | * @nr: the bit to change |
| 154 | * @addr: the address to start counting from |
| 155 | * |
| 156 | * Unlike change_bit(), this function is non-atomic and may be reordered. |
| 157 | * If it's called on the same region of memory simultaneously, the effect |
| 158 | * may be that only one operation succeeds. |
| 159 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 160 | static inline void __change_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 161 | { |
Simon Holm Thøgersen | eb2b4e6 | 2008-05-05 15:45:28 +0200 | [diff] [blame] | 162 | asm volatile("btc %1,%0" : ADDR : "Ir" (nr)); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 163 | } |
| 164 | |
| 165 | /** |
| 166 | * change_bit - Toggle a bit in memory |
| 167 | * @nr: Bit to change |
| 168 | * @addr: Address to start counting from |
| 169 | * |
| 170 | * change_bit() is atomic and may not be reordered. |
| 171 | * Note that @nr may be almost arbitrarily large; this function is not |
| 172 | * restricted to acting on a single-word quantity. |
| 173 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 174 | static inline void change_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 175 | { |
Uros Bizjak | 838e8bb | 2008-10-24 16:53:33 +0200 | [diff] [blame] | 176 | if (IS_IMMEDIATE(nr)) { |
| 177 | asm volatile(LOCK_PREFIX "xorb %1,%0" |
| 178 | : CONST_MASK_ADDR(nr, addr) |
| 179 | : "iq" ((u8)CONST_MASK(nr))); |
| 180 | } else { |
| 181 | asm volatile(LOCK_PREFIX "btc %1,%0" |
| 182 | : BITOP_ADDR(addr) |
| 183 | : "Ir" (nr)); |
| 184 | } |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 185 | } |
| 186 | |
| 187 | /** |
| 188 | * test_and_set_bit - Set a bit and return its old value |
| 189 | * @nr: Bit to set |
| 190 | * @addr: Address to count from |
| 191 | * |
| 192 | * This operation is atomic and cannot be reordered. |
| 193 | * It also implies a memory barrier. |
| 194 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 195 | static inline int test_and_set_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 196 | { |
| 197 | int oldbit; |
| 198 | |
| 199 | asm volatile(LOCK_PREFIX "bts %2,%1\n\t" |
Joe Perches | 286275c | 2008-03-23 01:01:45 -0700 | [diff] [blame] | 200 | "sbb %0,%0" : "=r" (oldbit), ADDR : "Ir" (nr) : "memory"); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 201 | |
| 202 | return oldbit; |
| 203 | } |
| 204 | |
| 205 | /** |
| 206 | * test_and_set_bit_lock - Set a bit and return its old value for lock |
| 207 | * @nr: Bit to set |
| 208 | * @addr: Address to count from |
| 209 | * |
| 210 | * This is the same as test_and_set_bit on x86. |
| 211 | */ |
Andi Kleen | c8399943 | 2009-01-12 23:01:15 +0100 | [diff] [blame] | 212 | static __always_inline int |
| 213 | test_and_set_bit_lock(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 214 | { |
| 215 | return test_and_set_bit(nr, addr); |
| 216 | } |
| 217 | |
| 218 | /** |
| 219 | * __test_and_set_bit - Set a bit and return its old value |
| 220 | * @nr: Bit to set |
| 221 | * @addr: Address to count from |
| 222 | * |
| 223 | * This operation is non-atomic and can be reordered. |
| 224 | * If two examples of this operation race, one can appear to succeed |
| 225 | * but actually fail. You must protect multiple accesses with a lock. |
| 226 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 227 | static inline int __test_and_set_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 228 | { |
| 229 | int oldbit; |
| 230 | |
Simon Holm Thøgersen | eb2b4e6 | 2008-05-05 15:45:28 +0200 | [diff] [blame] | 231 | asm("bts %2,%1\n\t" |
| 232 | "sbb %0,%0" |
| 233 | : "=r" (oldbit), ADDR |
| 234 | : "Ir" (nr)); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 235 | return oldbit; |
| 236 | } |
| 237 | |
| 238 | /** |
| 239 | * test_and_clear_bit - Clear a bit and return its old value |
| 240 | * @nr: Bit to clear |
| 241 | * @addr: Address to count from |
| 242 | * |
| 243 | * This operation is atomic and cannot be reordered. |
| 244 | * It also implies a memory barrier. |
| 245 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 246 | static inline int test_and_clear_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 247 | { |
| 248 | int oldbit; |
| 249 | |
| 250 | asm volatile(LOCK_PREFIX "btr %2,%1\n\t" |
| 251 | "sbb %0,%0" |
Joe Perches | 286275c | 2008-03-23 01:01:45 -0700 | [diff] [blame] | 252 | : "=r" (oldbit), ADDR : "Ir" (nr) : "memory"); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 253 | |
| 254 | return oldbit; |
| 255 | } |
| 256 | |
| 257 | /** |
| 258 | * __test_and_clear_bit - Clear a bit and return its old value |
| 259 | * @nr: Bit to clear |
| 260 | * @addr: Address to count from |
| 261 | * |
| 262 | * This operation is non-atomic and can be reordered. |
| 263 | * If two examples of this operation race, one can appear to succeed |
| 264 | * but actually fail. You must protect multiple accesses with a lock. |
| 265 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 266 | static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 267 | { |
| 268 | int oldbit; |
| 269 | |
Simon Holm Thøgersen | eb2b4e6 | 2008-05-05 15:45:28 +0200 | [diff] [blame] | 270 | asm volatile("btr %2,%1\n\t" |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 271 | "sbb %0,%0" |
Simon Holm Thøgersen | eb2b4e6 | 2008-05-05 15:45:28 +0200 | [diff] [blame] | 272 | : "=r" (oldbit), ADDR |
| 273 | : "Ir" (nr)); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 274 | return oldbit; |
| 275 | } |
| 276 | |
| 277 | /* WARNING: non atomic and it can be reordered! */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 278 | static inline int __test_and_change_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 279 | { |
| 280 | int oldbit; |
| 281 | |
Simon Holm Thøgersen | eb2b4e6 | 2008-05-05 15:45:28 +0200 | [diff] [blame] | 282 | asm volatile("btc %2,%1\n\t" |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 283 | "sbb %0,%0" |
Simon Holm Thøgersen | eb2b4e6 | 2008-05-05 15:45:28 +0200 | [diff] [blame] | 284 | : "=r" (oldbit), ADDR |
| 285 | : "Ir" (nr) : "memory"); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 286 | |
| 287 | return oldbit; |
| 288 | } |
| 289 | |
| 290 | /** |
| 291 | * test_and_change_bit - Change a bit and return its old value |
| 292 | * @nr: Bit to change |
| 293 | * @addr: Address to count from |
| 294 | * |
| 295 | * This operation is atomic and cannot be reordered. |
| 296 | * It also implies a memory barrier. |
| 297 | */ |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 298 | static inline int test_and_change_bit(int nr, volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 299 | { |
| 300 | int oldbit; |
| 301 | |
| 302 | asm volatile(LOCK_PREFIX "btc %2,%1\n\t" |
| 303 | "sbb %0,%0" |
Joe Perches | 286275c | 2008-03-23 01:01:45 -0700 | [diff] [blame] | 304 | : "=r" (oldbit), ADDR : "Ir" (nr) : "memory"); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 305 | |
| 306 | return oldbit; |
| 307 | } |
| 308 | |
Andi Kleen | c8399943 | 2009-01-12 23:01:15 +0100 | [diff] [blame] | 309 | static __always_inline int constant_test_bit(unsigned int nr, const volatile unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 310 | { |
Glauber de Oliveira Costa | 26996dd | 2008-01-30 13:31:31 +0100 | [diff] [blame] | 311 | return ((1UL << (nr % BITS_PER_LONG)) & |
| 312 | (((unsigned long *)addr)[nr / BITS_PER_LONG])) != 0; |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 313 | } |
| 314 | |
Andrew Morton | 5136dea | 2008-05-14 16:10:41 -0700 | [diff] [blame] | 315 | static inline int variable_test_bit(int nr, volatile const unsigned long *addr) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 316 | { |
| 317 | int oldbit; |
| 318 | |
Simon Holm Thøgersen | eb2b4e6 | 2008-05-05 15:45:28 +0200 | [diff] [blame] | 319 | asm volatile("bt %2,%1\n\t" |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 320 | "sbb %0,%0" |
| 321 | : "=r" (oldbit) |
Simon Holm Thøgersen | eb2b4e6 | 2008-05-05 15:45:28 +0200 | [diff] [blame] | 322 | : "m" (*(unsigned long *)addr), "Ir" (nr)); |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 323 | |
| 324 | return oldbit; |
| 325 | } |
| 326 | |
| 327 | #if 0 /* Fool kernel-doc since it doesn't do macros yet */ |
| 328 | /** |
| 329 | * test_bit - Determine whether a bit is set |
| 330 | * @nr: bit number to test |
| 331 | * @addr: Address to start counting from |
| 332 | */ |
| 333 | static int test_bit(int nr, const volatile unsigned long *addr); |
| 334 | #endif |
| 335 | |
Joe Perches | f19dcf4 | 2008-03-23 01:03:07 -0700 | [diff] [blame] | 336 | #define test_bit(nr, addr) \ |
| 337 | (__builtin_constant_p((nr)) \ |
| 338 | ? constant_test_bit((nr), (addr)) \ |
| 339 | : variable_test_bit((nr), (addr))) |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 340 | |
Alexander van Heukelum | 12d9c84 | 2008-03-15 13:04:42 +0100 | [diff] [blame] | 341 | /** |
| 342 | * __ffs - find first set bit in word |
| 343 | * @word: The word to search |
| 344 | * |
| 345 | * Undefined if no bit exists, so code should check against 0 first. |
| 346 | */ |
| 347 | static inline unsigned long __ffs(unsigned long word) |
| 348 | { |
Joe Perches | f19dcf4 | 2008-03-23 01:03:07 -0700 | [diff] [blame] | 349 | asm("bsf %1,%0" |
| 350 | : "=r" (word) |
| 351 | : "rm" (word)); |
Alexander van Heukelum | 12d9c84 | 2008-03-15 13:04:42 +0100 | [diff] [blame] | 352 | return word; |
| 353 | } |
| 354 | |
| 355 | /** |
| 356 | * ffz - find first zero bit in word |
| 357 | * @word: The word to search |
| 358 | * |
| 359 | * Undefined if no zero exists, so code should check against ~0UL first. |
| 360 | */ |
| 361 | static inline unsigned long ffz(unsigned long word) |
| 362 | { |
Joe Perches | f19dcf4 | 2008-03-23 01:03:07 -0700 | [diff] [blame] | 363 | asm("bsf %1,%0" |
| 364 | : "=r" (word) |
| 365 | : "r" (~word)); |
Alexander van Heukelum | 12d9c84 | 2008-03-15 13:04:42 +0100 | [diff] [blame] | 366 | return word; |
| 367 | } |
| 368 | |
| 369 | /* |
| 370 | * __fls: find last set bit in word |
| 371 | * @word: The word to search |
| 372 | * |
Alexander van Heukelum | 8450e85 | 2008-07-05 19:53:46 +0200 | [diff] [blame] | 373 | * Undefined if no set bit exists, so code should check against 0 first. |
Alexander van Heukelum | 12d9c84 | 2008-03-15 13:04:42 +0100 | [diff] [blame] | 374 | */ |
| 375 | static inline unsigned long __fls(unsigned long word) |
| 376 | { |
Joe Perches | f19dcf4 | 2008-03-23 01:03:07 -0700 | [diff] [blame] | 377 | asm("bsr %1,%0" |
| 378 | : "=r" (word) |
| 379 | : "rm" (word)); |
Alexander van Heukelum | 12d9c84 | 2008-03-15 13:04:42 +0100 | [diff] [blame] | 380 | return word; |
| 381 | } |
| 382 | |
| 383 | #ifdef __KERNEL__ |
| 384 | /** |
| 385 | * ffs - find first set bit in word |
| 386 | * @x: the word to search |
| 387 | * |
| 388 | * This is defined the same way as the libc and compiler builtin ffs |
| 389 | * routines, therefore differs in spirit from the other bitops. |
| 390 | * |
| 391 | * ffs(value) returns 0 if value is 0 or the position of the first |
| 392 | * set bit if value is nonzero. The first (least significant) bit |
| 393 | * is at position 1. |
| 394 | */ |
| 395 | static inline int ffs(int x) |
| 396 | { |
| 397 | int r; |
| 398 | #ifdef CONFIG_X86_CMOV |
Joe Perches | f19dcf4 | 2008-03-23 01:03:07 -0700 | [diff] [blame] | 399 | asm("bsfl %1,%0\n\t" |
| 400 | "cmovzl %2,%0" |
| 401 | : "=r" (r) : "rm" (x), "r" (-1)); |
Alexander van Heukelum | 12d9c84 | 2008-03-15 13:04:42 +0100 | [diff] [blame] | 402 | #else |
Joe Perches | f19dcf4 | 2008-03-23 01:03:07 -0700 | [diff] [blame] | 403 | asm("bsfl %1,%0\n\t" |
| 404 | "jnz 1f\n\t" |
| 405 | "movl $-1,%0\n" |
| 406 | "1:" : "=r" (r) : "rm" (x)); |
Alexander van Heukelum | 12d9c84 | 2008-03-15 13:04:42 +0100 | [diff] [blame] | 407 | #endif |
| 408 | return r + 1; |
| 409 | } |
| 410 | |
| 411 | /** |
| 412 | * fls - find last set bit in word |
| 413 | * @x: the word to search |
| 414 | * |
| 415 | * This is defined in a similar way as the libc and compiler builtin |
| 416 | * ffs, but returns the position of the most significant set bit. |
| 417 | * |
| 418 | * fls(value) returns 0 if value is 0 or the position of the last |
| 419 | * set bit if value is nonzero. The last (most significant) bit is |
| 420 | * at position 32. |
| 421 | */ |
| 422 | static inline int fls(int x) |
| 423 | { |
| 424 | int r; |
| 425 | #ifdef CONFIG_X86_CMOV |
Joe Perches | f19dcf4 | 2008-03-23 01:03:07 -0700 | [diff] [blame] | 426 | asm("bsrl %1,%0\n\t" |
| 427 | "cmovzl %2,%0" |
| 428 | : "=&r" (r) : "rm" (x), "rm" (-1)); |
Alexander van Heukelum | 12d9c84 | 2008-03-15 13:04:42 +0100 | [diff] [blame] | 429 | #else |
Joe Perches | f19dcf4 | 2008-03-23 01:03:07 -0700 | [diff] [blame] | 430 | asm("bsrl %1,%0\n\t" |
| 431 | "jnz 1f\n\t" |
| 432 | "movl $-1,%0\n" |
| 433 | "1:" : "=r" (r) : "rm" (x)); |
Alexander van Heukelum | 12d9c84 | 2008-03-15 13:04:42 +0100 | [diff] [blame] | 434 | #endif |
| 435 | return r + 1; |
| 436 | } |
| 437 | #endif /* __KERNEL__ */ |
| 438 | |
Jeremy Fitzhardinge | 1c54d77 | 2008-01-30 13:30:55 +0100 | [diff] [blame] | 439 | #undef ADDR |
| 440 | |
Alexander van Heukelum | d66462f | 2008-04-04 20:49:30 +0200 | [diff] [blame] | 441 | #ifdef __KERNEL__ |
| 442 | |
| 443 | #include <asm-generic/bitops/sched.h> |
| 444 | |
| 445 | #define ARCH_HAS_FAST_MULTIPLIER 1 |
| 446 | |
Borislav Petkov | d61931d | 2010-03-05 17:34:46 +0100 | [diff] [blame^] | 447 | #include <asm/arch_hweight.h> |
| 448 | |
| 449 | #include <asm-generic/bitops/const_hweight.h> |
Alexander van Heukelum | d66462f | 2008-04-04 20:49:30 +0200 | [diff] [blame] | 450 | |
| 451 | #endif /* __KERNEL__ */ |
| 452 | |
| 453 | #include <asm-generic/bitops/fls64.h> |
| 454 | |
| 455 | #ifdef __KERNEL__ |
| 456 | |
| 457 | #include <asm-generic/bitops/ext2-non-atomic.h> |
| 458 | |
| 459 | #define ext2_set_bit_atomic(lock, nr, addr) \ |
| 460 | test_and_set_bit((nr), (unsigned long *)(addr)) |
| 461 | #define ext2_clear_bit_atomic(lock, nr, addr) \ |
| 462 | test_and_clear_bit((nr), (unsigned long *)(addr)) |
| 463 | |
| 464 | #include <asm-generic/bitops/minix.h> |
| 465 | |
| 466 | #endif /* __KERNEL__ */ |
H. Peter Anvin | 1965aae | 2008-10-22 22:26:29 -0700 | [diff] [blame] | 467 | #endif /* _ASM_X86_BITOPS_H */ |