Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
edf7b938 | 2 | * Atomic operations that C can't guarantee us. Useful for |
1da177e4 LT |
3 | * resource counting etc.. |
4 | * | |
5 | * But use these as seldom as possible since they are much more slower | |
6 | * than regular operations. | |
7 | * | |
8 | * This file is subject to the terms and conditions of the GNU General Public | |
9 | * License. See the file "COPYING" in the main directory of this archive | |
10 | * for more details. | |
11 | * | |
e303e088 | 12 | * Copyright (C) 1996, 97, 99, 2000, 03, 04, 06 by Ralf Baechle |
1da177e4 | 13 | */ |
1da177e4 LT |
14 | #ifndef _ASM_ATOMIC_H |
15 | #define _ASM_ATOMIC_H | |
16 | ||
192ef366 | 17 | #include <linux/irqflags.h> |
ea435467 | 18 | #include <linux/types.h> |
0004a9df | 19 | #include <asm/barrier.h> |
b0984c43 | 20 | #include <asm/compiler.h> |
1da177e4 | 21 | #include <asm/cpu-features.h> |
b81947c6 | 22 | #include <asm/cmpxchg.h> |
1da177e4 LT |
23 | #include <asm/war.h> |
24 | ||
70342287 | 25 | #define ATOMIC_INIT(i) { (i) } |
1da177e4 LT |
26 | |
27 | /* | |
28 | * atomic_read - read atomic variable | |
29 | * @v: pointer of type atomic_t | |
30 | * | |
31 | * Atomically reads the value of @v. | |
32 | */ | |
62e8a325 | 33 | #define atomic_read(v) READ_ONCE((v)->counter) |
1da177e4 LT |
34 | |
35 | /* | |
36 | * atomic_set - set atomic variable | |
37 | * @v: pointer of type atomic_t | |
38 | * @i: required value | |
39 | * | |
40 | * Atomically sets the value of @v to @i. | |
41 | */ | |
62e8a325 | 42 | #define atomic_set(v, i) WRITE_ONCE((v)->counter, (i)) |
1da177e4 | 43 | |
ddb3108e MR |
44 | #define ATOMIC_OP(op, c_op, asm_op) \ |
45 | static __inline__ void atomic_##op(int i, atomic_t * v) \ | |
46 | { \ | |
47 | if (kernel_uses_llsc && R10000_LLSC_WAR) { \ | |
48 | int temp; \ | |
49 | \ | |
50 | __asm__ __volatile__( \ | |
51 | " .set arch=r4000 \n" \ | |
52 | "1: ll %0, %1 # atomic_" #op " \n" \ | |
53 | " " #asm_op " %0, %2 \n" \ | |
54 | " sc %0, %1 \n" \ | |
55 | " beqzl %0, 1b \n" \ | |
56 | " .set mips0 \n" \ | |
94bfb75a | 57 | : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) \ |
ddb3108e MR |
58 | : "Ir" (i)); \ |
59 | } else if (kernel_uses_llsc) { \ | |
60 | int temp; \ | |
61 | \ | |
62 | do { \ | |
63 | __asm__ __volatile__( \ | |
0038df22 | 64 | " .set "MIPS_ISA_LEVEL" \n" \ |
ddb3108e MR |
65 | " ll %0, %1 # atomic_" #op "\n" \ |
66 | " " #asm_op " %0, %2 \n" \ | |
67 | " sc %0, %1 \n" \ | |
68 | " .set mips0 \n" \ | |
94bfb75a | 69 | : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) \ |
ddb3108e MR |
70 | : "Ir" (i)); \ |
71 | } while (unlikely(!temp)); \ | |
72 | } else { \ | |
73 | unsigned long flags; \ | |
74 | \ | |
75 | raw_local_irq_save(flags); \ | |
76 | v->counter c_op i; \ | |
77 | raw_local_irq_restore(flags); \ | |
78 | } \ | |
1da177e4 LT |
79 | } |
80 | ||
ddb3108e MR |
81 | #define ATOMIC_OP_RETURN(op, c_op, asm_op) \ |
82 | static __inline__ int atomic_##op##_return(int i, atomic_t * v) \ | |
83 | { \ | |
84 | int result; \ | |
85 | \ | |
86 | smp_mb__before_llsc(); \ | |
87 | \ | |
88 | if (kernel_uses_llsc && R10000_LLSC_WAR) { \ | |
89 | int temp; \ | |
90 | \ | |
91 | __asm__ __volatile__( \ | |
92 | " .set arch=r4000 \n" \ | |
93 | "1: ll %1, %2 # atomic_" #op "_return \n" \ | |
94 | " " #asm_op " %0, %1, %3 \n" \ | |
95 | " sc %0, %2 \n" \ | |
96 | " beqzl %0, 1b \n" \ | |
97 | " " #asm_op " %0, %1, %3 \n" \ | |
98 | " .set mips0 \n" \ | |
99 | : "=&r" (result), "=&r" (temp), \ | |
94bfb75a | 100 | "+" GCC_OFF_SMALL_ASM() (v->counter) \ |
ddb3108e MR |
101 | : "Ir" (i)); \ |
102 | } else if (kernel_uses_llsc) { \ | |
103 | int temp; \ | |
104 | \ | |
105 | do { \ | |
106 | __asm__ __volatile__( \ | |
0038df22 | 107 | " .set "MIPS_ISA_LEVEL" \n" \ |
ddb3108e MR |
108 | " ll %1, %2 # atomic_" #op "_return \n" \ |
109 | " " #asm_op " %0, %1, %3 \n" \ | |
110 | " sc %0, %2 \n" \ | |
111 | " .set mips0 \n" \ | |
112 | : "=&r" (result), "=&r" (temp), \ | |
94bfb75a | 113 | "+" GCC_OFF_SMALL_ASM() (v->counter) \ |
ddb3108e MR |
114 | : "Ir" (i)); \ |
115 | } while (unlikely(!result)); \ | |
116 | \ | |
117 | result = temp; result c_op i; \ | |
118 | } else { \ | |
119 | unsigned long flags; \ | |
120 | \ | |
121 | raw_local_irq_save(flags); \ | |
122 | result = v->counter; \ | |
123 | result c_op i; \ | |
124 | v->counter = result; \ | |
125 | raw_local_irq_restore(flags); \ | |
126 | } \ | |
127 | \ | |
128 | smp_llsc_mb(); \ | |
129 | \ | |
130 | return result; \ | |
131 | } | |
132 | ||
133 | #define ATOMIC_OPS(op, c_op, asm_op) \ | |
134 | ATOMIC_OP(op, c_op, asm_op) \ | |
ef31563e | 135 | ATOMIC_OP_RETURN(op, c_op, asm_op) |
1da177e4 | 136 | |
ef31563e PZ |
137 | ATOMIC_OPS(add, +=, addu) |
138 | ATOMIC_OPS(sub, -=, subu) | |
1da177e4 | 139 | |
27782f27 PZ |
140 | ATOMIC_OP(and, &=, and) |
141 | ATOMIC_OP(or, |=, or) | |
142 | ATOMIC_OP(xor, ^=, xor) | |
143 | ||
ef31563e PZ |
144 | #undef ATOMIC_OPS |
145 | #undef ATOMIC_OP_RETURN | |
146 | #undef ATOMIC_OP | |
1da177e4 LT |
147 | |
148 | /* | |
f10d14dd AG |
149 | * atomic_sub_if_positive - conditionally subtract integer from atomic variable |
150 | * @i: integer value to subtract | |
1da177e4 LT |
151 | * @v: pointer of type atomic_t |
152 | * | |
f10d14dd AG |
153 | * Atomically test @v and subtract @i if @v is greater or equal than @i. |
154 | * The function returns the old value of @v minus @i. | |
1da177e4 LT |
155 | */ |
156 | static __inline__ int atomic_sub_if_positive(int i, atomic_t * v) | |
157 | { | |
915ec1e2 | 158 | int result; |
1da177e4 | 159 | |
f252ffd5 | 160 | smp_mb__before_llsc(); |
0004a9df | 161 | |
b791d119 | 162 | if (kernel_uses_llsc && R10000_LLSC_WAR) { |
915ec1e2 | 163 | int temp; |
1da177e4 LT |
164 | |
165 | __asm__ __volatile__( | |
a809d460 | 166 | " .set arch=r4000 \n" |
1da177e4 LT |
167 | "1: ll %1, %2 # atomic_sub_if_positive\n" |
168 | " subu %0, %1, %3 \n" | |
169 | " bltz %0, 1f \n" | |
170 | " sc %0, %2 \n" | |
92f22c18 | 171 | " .set noreorder \n" |
1da177e4 | 172 | " beqzl %0, 1b \n" |
92f22c18 RB |
173 | " subu %0, %1, %3 \n" |
174 | " .set reorder \n" | |
1da177e4 | 175 | "1: \n" |
aac8aa77 | 176 | " .set mips0 \n" |
b0984c43 | 177 | : "=&r" (result), "=&r" (temp), |
94bfb75a MC |
178 | "+" GCC_OFF_SMALL_ASM() (v->counter) |
179 | : "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter) | |
1da177e4 | 180 | : "memory"); |
b791d119 | 181 | } else if (kernel_uses_llsc) { |
915ec1e2 | 182 | int temp; |
1da177e4 LT |
183 | |
184 | __asm__ __volatile__( | |
0038df22 | 185 | " .set "MIPS_ISA_LEVEL" \n" |
1da177e4 LT |
186 | "1: ll %1, %2 # atomic_sub_if_positive\n" |
187 | " subu %0, %1, %3 \n" | |
188 | " bltz %0, 1f \n" | |
189 | " sc %0, %2 \n" | |
92f22c18 | 190 | " .set noreorder \n" |
7837314d | 191 | " beqz %0, 1b \n" |
92f22c18 RB |
192 | " subu %0, %1, %3 \n" |
193 | " .set reorder \n" | |
50952026 | 194 | "1: \n" |
aac8aa77 | 195 | " .set mips0 \n" |
b0984c43 | 196 | : "=&r" (result), "=&r" (temp), |
94bfb75a | 197 | "+" GCC_OFF_SMALL_ASM() (v->counter) |
b4f2a17b | 198 | : "Ir" (i)); |
1da177e4 LT |
199 | } else { |
200 | unsigned long flags; | |
201 | ||
49edd098 | 202 | raw_local_irq_save(flags); |
1da177e4 LT |
203 | result = v->counter; |
204 | result -= i; | |
205 | if (result >= 0) | |
206 | v->counter = result; | |
49edd098 | 207 | raw_local_irq_restore(flags); |
1da177e4 LT |
208 | } |
209 | ||
17099b11 | 210 | smp_llsc_mb(); |
0004a9df | 211 | |
1da177e4 LT |
212 | return result; |
213 | } | |
214 | ||
e12f644b MD |
215 | #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) |
216 | #define atomic_xchg(v, new) (xchg(&((v)->counter), (new))) | |
4a6dae6d | 217 | |
8426e1f6 | 218 | /** |
f24219b4 | 219 | * __atomic_add_unless - add unless the number is a given value |
8426e1f6 NP |
220 | * @v: pointer of type atomic_t |
221 | * @a: the amount to add to v... | |
222 | * @u: ...unless v is equal to u. | |
223 | * | |
224 | * Atomically adds @a to @v, so long as it was not @u. | |
f24219b4 | 225 | * Returns the old value of @v. |
8426e1f6 | 226 | */ |
f24219b4 | 227 | static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u) |
2856f5e3 MD |
228 | { |
229 | int c, old; | |
230 | c = atomic_read(v); | |
231 | for (;;) { | |
232 | if (unlikely(c == (u))) | |
233 | break; | |
234 | old = atomic_cmpxchg((v), c, c + (a)); | |
235 | if (likely(old == c)) | |
236 | break; | |
237 | c = old; | |
238 | } | |
f24219b4 | 239 | return c; |
2856f5e3 | 240 | } |
8426e1f6 | 241 | |
21a151d8 RB |
242 | #define atomic_dec_return(v) atomic_sub_return(1, (v)) |
243 | #define atomic_inc_return(v) atomic_add_return(1, (v)) | |
1da177e4 LT |
244 | |
245 | /* | |
246 | * atomic_sub_and_test - subtract value from variable and test result | |
247 | * @i: integer value to subtract | |
248 | * @v: pointer of type atomic_t | |
249 | * | |
250 | * Atomically subtracts @i from @v and returns | |
251 | * true if the result is zero, or false for all | |
252 | * other cases. | |
253 | */ | |
21a151d8 | 254 | #define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0) |
1da177e4 LT |
255 | |
256 | /* | |
257 | * atomic_inc_and_test - increment and test | |
258 | * @v: pointer of type atomic_t | |
259 | * | |
260 | * Atomically increments @v by 1 | |
261 | * and returns true if the result is zero, or false for all | |
262 | * other cases. | |
263 | */ | |
264 | #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) | |
265 | ||
266 | /* | |
267 | * atomic_dec_and_test - decrement by 1 and test | |
268 | * @v: pointer of type atomic_t | |
269 | * | |
270 | * Atomically decrements @v by 1 and | |
271 | * returns true if the result is 0, or false for all other | |
272 | * cases. | |
273 | */ | |
274 | #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) | |
275 | ||
276 | /* | |
277 | * atomic_dec_if_positive - decrement by 1 if old value positive | |
278 | * @v: pointer of type atomic_t | |
279 | */ | |
280 | #define atomic_dec_if_positive(v) atomic_sub_if_positive(1, v) | |
281 | ||
282 | /* | |
283 | * atomic_inc - increment atomic variable | |
284 | * @v: pointer of type atomic_t | |
285 | * | |
286 | * Atomically increments @v by 1. | |
287 | */ | |
21a151d8 | 288 | #define atomic_inc(v) atomic_add(1, (v)) |
1da177e4 LT |
289 | |
290 | /* | |
291 | * atomic_dec - decrement and test | |
292 | * @v: pointer of type atomic_t | |
293 | * | |
294 | * Atomically decrements @v by 1. | |
295 | */ | |
21a151d8 | 296 | #define atomic_dec(v) atomic_sub(1, (v)) |
1da177e4 LT |
297 | |
298 | /* | |
299 | * atomic_add_negative - add and test if negative | |
300 | * @v: pointer of type atomic_t | |
301 | * @i: integer value to add | |
302 | * | |
303 | * Atomically adds @i to @v and returns true | |
304 | * if the result is negative, or false when | |
305 | * result is greater than or equal to zero. | |
306 | */ | |
21a151d8 | 307 | #define atomic_add_negative(i, v) (atomic_add_return(i, (v)) < 0) |
1da177e4 | 308 | |
875d43e7 | 309 | #ifdef CONFIG_64BIT |
1da177e4 | 310 | |
1da177e4 LT |
311 | #define ATOMIC64_INIT(i) { (i) } |
312 | ||
313 | /* | |
314 | * atomic64_read - read atomic variable | |
315 | * @v: pointer of type atomic64_t | |
316 | * | |
317 | */ | |
62e8a325 | 318 | #define atomic64_read(v) READ_ONCE((v)->counter) |
1da177e4 LT |
319 | |
320 | /* | |
321 | * atomic64_set - set atomic variable | |
322 | * @v: pointer of type atomic64_t | |
323 | * @i: required value | |
324 | */ | |
62e8a325 | 325 | #define atomic64_set(v, i) WRITE_ONCE((v)->counter, (i)) |
1da177e4 | 326 | |
ddb3108e MR |
327 | #define ATOMIC64_OP(op, c_op, asm_op) \ |
328 | static __inline__ void atomic64_##op(long i, atomic64_t * v) \ | |
329 | { \ | |
330 | if (kernel_uses_llsc && R10000_LLSC_WAR) { \ | |
331 | long temp; \ | |
332 | \ | |
333 | __asm__ __volatile__( \ | |
334 | " .set arch=r4000 \n" \ | |
335 | "1: lld %0, %1 # atomic64_" #op " \n" \ | |
336 | " " #asm_op " %0, %2 \n" \ | |
337 | " scd %0, %1 \n" \ | |
338 | " beqzl %0, 1b \n" \ | |
339 | " .set mips0 \n" \ | |
94bfb75a | 340 | : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) \ |
ddb3108e MR |
341 | : "Ir" (i)); \ |
342 | } else if (kernel_uses_llsc) { \ | |
343 | long temp; \ | |
344 | \ | |
345 | do { \ | |
346 | __asm__ __volatile__( \ | |
0038df22 | 347 | " .set "MIPS_ISA_LEVEL" \n" \ |
ddb3108e MR |
348 | " lld %0, %1 # atomic64_" #op "\n" \ |
349 | " " #asm_op " %0, %2 \n" \ | |
350 | " scd %0, %1 \n" \ | |
351 | " .set mips0 \n" \ | |
94bfb75a | 352 | : "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) \ |
ddb3108e MR |
353 | : "Ir" (i)); \ |
354 | } while (unlikely(!temp)); \ | |
355 | } else { \ | |
356 | unsigned long flags; \ | |
357 | \ | |
358 | raw_local_irq_save(flags); \ | |
359 | v->counter c_op i; \ | |
360 | raw_local_irq_restore(flags); \ | |
361 | } \ | |
362 | } | |
363 | ||
364 | #define ATOMIC64_OP_RETURN(op, c_op, asm_op) \ | |
365 | static __inline__ long atomic64_##op##_return(long i, atomic64_t * v) \ | |
366 | { \ | |
367 | long result; \ | |
368 | \ | |
369 | smp_mb__before_llsc(); \ | |
370 | \ | |
371 | if (kernel_uses_llsc && R10000_LLSC_WAR) { \ | |
372 | long temp; \ | |
373 | \ | |
374 | __asm__ __volatile__( \ | |
375 | " .set arch=r4000 \n" \ | |
376 | "1: lld %1, %2 # atomic64_" #op "_return\n" \ | |
377 | " " #asm_op " %0, %1, %3 \n" \ | |
378 | " scd %0, %2 \n" \ | |
379 | " beqzl %0, 1b \n" \ | |
380 | " " #asm_op " %0, %1, %3 \n" \ | |
381 | " .set mips0 \n" \ | |
382 | : "=&r" (result), "=&r" (temp), \ | |
94bfb75a | 383 | "+" GCC_OFF_SMALL_ASM() (v->counter) \ |
ddb3108e MR |
384 | : "Ir" (i)); \ |
385 | } else if (kernel_uses_llsc) { \ | |
386 | long temp; \ | |
387 | \ | |
388 | do { \ | |
389 | __asm__ __volatile__( \ | |
0038df22 | 390 | " .set "MIPS_ISA_LEVEL" \n" \ |
ddb3108e MR |
391 | " lld %1, %2 # atomic64_" #op "_return\n" \ |
392 | " " #asm_op " %0, %1, %3 \n" \ | |
393 | " scd %0, %2 \n" \ | |
394 | " .set mips0 \n" \ | |
395 | : "=&r" (result), "=&r" (temp), \ | |
94bfb75a MC |
396 | "=" GCC_OFF_SMALL_ASM() (v->counter) \ |
397 | : "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter) \ | |
ddb3108e MR |
398 | : "memory"); \ |
399 | } while (unlikely(!result)); \ | |
400 | \ | |
401 | result = temp; result c_op i; \ | |
402 | } else { \ | |
403 | unsigned long flags; \ | |
404 | \ | |
405 | raw_local_irq_save(flags); \ | |
406 | result = v->counter; \ | |
407 | result c_op i; \ | |
408 | v->counter = result; \ | |
409 | raw_local_irq_restore(flags); \ | |
410 | } \ | |
411 | \ | |
412 | smp_llsc_mb(); \ | |
413 | \ | |
414 | return result; \ | |
1da177e4 LT |
415 | } |
416 | ||
ddb3108e MR |
417 | #define ATOMIC64_OPS(op, c_op, asm_op) \ |
418 | ATOMIC64_OP(op, c_op, asm_op) \ | |
ef31563e | 419 | ATOMIC64_OP_RETURN(op, c_op, asm_op) |
1da177e4 | 420 | |
ef31563e PZ |
421 | ATOMIC64_OPS(add, +=, daddu) |
422 | ATOMIC64_OPS(sub, -=, dsubu) | |
27782f27 PZ |
423 | ATOMIC64_OP(and, &=, and) |
424 | ATOMIC64_OP(or, |=, or) | |
425 | ATOMIC64_OP(xor, ^=, xor) | |
1da177e4 | 426 | |
ef31563e PZ |
427 | #undef ATOMIC64_OPS |
428 | #undef ATOMIC64_OP_RETURN | |
429 | #undef ATOMIC64_OP | |
1da177e4 LT |
430 | |
431 | /* | |
ddb3108e MR |
432 | * atomic64_sub_if_positive - conditionally subtract integer from atomic |
433 | * variable | |
f10d14dd | 434 | * @i: integer value to subtract |
1da177e4 LT |
435 | * @v: pointer of type atomic64_t |
436 | * | |
f10d14dd AG |
437 | * Atomically test @v and subtract @i if @v is greater or equal than @i. |
438 | * The function returns the old value of @v minus @i. | |
1da177e4 LT |
439 | */ |
440 | static __inline__ long atomic64_sub_if_positive(long i, atomic64_t * v) | |
441 | { | |
915ec1e2 | 442 | long result; |
1da177e4 | 443 | |
f252ffd5 | 444 | smp_mb__before_llsc(); |
0004a9df | 445 | |
b791d119 | 446 | if (kernel_uses_llsc && R10000_LLSC_WAR) { |
915ec1e2 | 447 | long temp; |
1da177e4 LT |
448 | |
449 | __asm__ __volatile__( | |
a809d460 | 450 | " .set arch=r4000 \n" |
1da177e4 LT |
451 | "1: lld %1, %2 # atomic64_sub_if_positive\n" |
452 | " dsubu %0, %1, %3 \n" | |
453 | " bltz %0, 1f \n" | |
454 | " scd %0, %2 \n" | |
92f22c18 | 455 | " .set noreorder \n" |
1da177e4 | 456 | " beqzl %0, 1b \n" |
92f22c18 RB |
457 | " dsubu %0, %1, %3 \n" |
458 | " .set reorder \n" | |
1da177e4 | 459 | "1: \n" |
aac8aa77 | 460 | " .set mips0 \n" |
b0984c43 | 461 | : "=&r" (result), "=&r" (temp), |
94bfb75a MC |
462 | "=" GCC_OFF_SMALL_ASM() (v->counter) |
463 | : "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter) | |
1da177e4 | 464 | : "memory"); |
b791d119 | 465 | } else if (kernel_uses_llsc) { |
915ec1e2 | 466 | long temp; |
1da177e4 LT |
467 | |
468 | __asm__ __volatile__( | |
0038df22 | 469 | " .set "MIPS_ISA_LEVEL" \n" |
1da177e4 LT |
470 | "1: lld %1, %2 # atomic64_sub_if_positive\n" |
471 | " dsubu %0, %1, %3 \n" | |
472 | " bltz %0, 1f \n" | |
473 | " scd %0, %2 \n" | |
92f22c18 | 474 | " .set noreorder \n" |
7837314d | 475 | " beqz %0, 1b \n" |
92f22c18 RB |
476 | " dsubu %0, %1, %3 \n" |
477 | " .set reorder \n" | |
50952026 | 478 | "1: \n" |
aac8aa77 | 479 | " .set mips0 \n" |
b0984c43 | 480 | : "=&r" (result), "=&r" (temp), |
94bfb75a | 481 | "+" GCC_OFF_SMALL_ASM() (v->counter) |
b4f2a17b | 482 | : "Ir" (i)); |
1da177e4 LT |
483 | } else { |
484 | unsigned long flags; | |
485 | ||
49edd098 | 486 | raw_local_irq_save(flags); |
1da177e4 LT |
487 | result = v->counter; |
488 | result -= i; | |
489 | if (result >= 0) | |
490 | v->counter = result; | |
49edd098 | 491 | raw_local_irq_restore(flags); |
1da177e4 LT |
492 | } |
493 | ||
17099b11 | 494 | smp_llsc_mb(); |
0004a9df | 495 | |
1da177e4 LT |
496 | return result; |
497 | } | |
498 | ||
e12f644b | 499 | #define atomic64_cmpxchg(v, o, n) \ |
7b239bb1 | 500 | ((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n))) |
e12f644b MD |
501 | #define atomic64_xchg(v, new) (xchg(&((v)->counter), (new))) |
502 | ||
503 | /** | |
504 | * atomic64_add_unless - add unless the number is a given value | |
505 | * @v: pointer of type atomic64_t | |
506 | * @a: the amount to add to v... | |
507 | * @u: ...unless v is equal to u. | |
508 | * | |
509 | * Atomically adds @a to @v, so long as it was not @u. | |
f25319d2 | 510 | * Returns true iff @v was not @u. |
e12f644b | 511 | */ |
2856f5e3 MD |
512 | static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u) |
513 | { | |
514 | long c, old; | |
515 | c = atomic64_read(v); | |
516 | for (;;) { | |
517 | if (unlikely(c == (u))) | |
518 | break; | |
519 | old = atomic64_cmpxchg((v), c, c + (a)); | |
520 | if (likely(old == c)) | |
521 | break; | |
522 | c = old; | |
523 | } | |
524 | return c != (u); | |
525 | } | |
526 | ||
e12f644b MD |
527 | #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) |
528 | ||
21a151d8 RB |
529 | #define atomic64_dec_return(v) atomic64_sub_return(1, (v)) |
530 | #define atomic64_inc_return(v) atomic64_add_return(1, (v)) | |
1da177e4 LT |
531 | |
532 | /* | |
533 | * atomic64_sub_and_test - subtract value from variable and test result | |
534 | * @i: integer value to subtract | |
535 | * @v: pointer of type atomic64_t | |
536 | * | |
537 | * Atomically subtracts @i from @v and returns | |
538 | * true if the result is zero, or false for all | |
539 | * other cases. | |
540 | */ | |
21a151d8 | 541 | #define atomic64_sub_and_test(i, v) (atomic64_sub_return((i), (v)) == 0) |
1da177e4 LT |
542 | |
543 | /* | |
544 | * atomic64_inc_and_test - increment and test | |
545 | * @v: pointer of type atomic64_t | |
546 | * | |
547 | * Atomically increments @v by 1 | |
548 | * and returns true if the result is zero, or false for all | |
549 | * other cases. | |
550 | */ | |
551 | #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0) | |
552 | ||
553 | /* | |
554 | * atomic64_dec_and_test - decrement by 1 and test | |
555 | * @v: pointer of type atomic64_t | |
556 | * | |
557 | * Atomically decrements @v by 1 and | |
558 | * returns true if the result is 0, or false for all other | |
559 | * cases. | |
560 | */ | |
561 | #define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0) | |
562 | ||
563 | /* | |
564 | * atomic64_dec_if_positive - decrement by 1 if old value positive | |
565 | * @v: pointer of type atomic64_t | |
566 | */ | |
567 | #define atomic64_dec_if_positive(v) atomic64_sub_if_positive(1, v) | |
568 | ||
569 | /* | |
570 | * atomic64_inc - increment atomic variable | |
571 | * @v: pointer of type atomic64_t | |
572 | * | |
573 | * Atomically increments @v by 1. | |
574 | */ | |
21a151d8 | 575 | #define atomic64_inc(v) atomic64_add(1, (v)) |
1da177e4 LT |
576 | |
577 | /* | |
578 | * atomic64_dec - decrement and test | |
579 | * @v: pointer of type atomic64_t | |
580 | * | |
581 | * Atomically decrements @v by 1. | |
582 | */ | |
21a151d8 | 583 | #define atomic64_dec(v) atomic64_sub(1, (v)) |
1da177e4 LT |
584 | |
585 | /* | |
586 | * atomic64_add_negative - add and test if negative | |
587 | * @v: pointer of type atomic64_t | |
588 | * @i: integer value to add | |
589 | * | |
590 | * Atomically adds @i to @v and returns true | |
591 | * if the result is negative, or false when | |
592 | * result is greater than or equal to zero. | |
593 | */ | |
21a151d8 | 594 | #define atomic64_add_negative(i, v) (atomic64_add_return(i, (v)) < 0) |
1da177e4 | 595 | |
875d43e7 | 596 | #endif /* CONFIG_64BIT */ |
1da177e4 | 597 | |
1da177e4 | 598 | #endif /* _ASM_ATOMIC_H */ |