atomic.h 10 KB

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  1. #ifndef _ASM_POWERPC_ATOMIC_H_
  2. #define _ASM_POWERPC_ATOMIC_H_
  3. /*
  4. * PowerPC atomic operations
  5. */
  6. #include <linux/types.h>
  7. #ifdef __KERNEL__
  8. #include <linux/compiler.h>
  9. #include <asm/synch.h>
  10. #include <asm/asm-compat.h>
  11. #include <asm/system.h>
  12. #define ATOMIC_INIT(i) { (i) }
  13. static __inline__ int atomic_read(const atomic_t *v)
  14. {
  15. int t;
  16. __asm__ __volatile__("lwz%U1%X1 %0,%1" : "=r"(t) : "m"(v->counter));
  17. return t;
  18. }
  19. static __inline__ void atomic_set(atomic_t *v, int i)
  20. {
  21. __asm__ __volatile__("stw%U0%X0 %1,%0" : "=m"(v->counter) : "r"(i));
  22. }
  23. static __inline__ void atomic_add(int a, atomic_t *v)
  24. {
  25. int t;
  26. __asm__ __volatile__(
  27. "1: lwarx %0,0,%3 # atomic_add\n\
  28. add %0,%2,%0\n"
  29. PPC405_ERR77(0,%3)
  30. " stwcx. %0,0,%3 \n\
  31. bne- 1b"
  32. : "=&r" (t), "+m" (v->counter)
  33. : "r" (a), "r" (&v->counter)
  34. : "cc");
  35. }
  36. static __inline__ int atomic_add_return(int a, atomic_t *v)
  37. {
  38. int t;
  39. __asm__ __volatile__(
  40. PPC_ATOMIC_ENTRY_BARRIER
  41. "1: lwarx %0,0,%2 # atomic_add_return\n\
  42. add %0,%1,%0\n"
  43. PPC405_ERR77(0,%2)
  44. " stwcx. %0,0,%2 \n\
  45. bne- 1b"
  46. PPC_ATOMIC_EXIT_BARRIER
  47. : "=&r" (t)
  48. : "r" (a), "r" (&v->counter)
  49. : "cc", "memory");
  50. return t;
  51. }
  52. #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
  53. static __inline__ void atomic_sub(int a, atomic_t *v)
  54. {
  55. int t;
  56. __asm__ __volatile__(
  57. "1: lwarx %0,0,%3 # atomic_sub\n\
  58. subf %0,%2,%0\n"
  59. PPC405_ERR77(0,%3)
  60. " stwcx. %0,0,%3 \n\
  61. bne- 1b"
  62. : "=&r" (t), "+m" (v->counter)
  63. : "r" (a), "r" (&v->counter)
  64. : "cc");
  65. }
  66. static __inline__ int atomic_sub_return(int a, atomic_t *v)
  67. {
  68. int t;
  69. __asm__ __volatile__(
  70. PPC_ATOMIC_ENTRY_BARRIER
  71. "1: lwarx %0,0,%2 # atomic_sub_return\n\
  72. subf %0,%1,%0\n"
  73. PPC405_ERR77(0,%2)
  74. " stwcx. %0,0,%2 \n\
  75. bne- 1b"
  76. PPC_ATOMIC_EXIT_BARRIER
  77. : "=&r" (t)
  78. : "r" (a), "r" (&v->counter)
  79. : "cc", "memory");
  80. return t;
  81. }
  82. static __inline__ void atomic_inc(atomic_t *v)
  83. {
  84. int t;
  85. __asm__ __volatile__(
  86. "1: lwarx %0,0,%2 # atomic_inc\n\
  87. addic %0,%0,1\n"
  88. PPC405_ERR77(0,%2)
  89. " stwcx. %0,0,%2 \n\
  90. bne- 1b"
  91. : "=&r" (t), "+m" (v->counter)
  92. : "r" (&v->counter)
  93. : "cc", "xer");
  94. }
  95. static __inline__ int atomic_inc_return(atomic_t *v)
  96. {
  97. int t;
  98. __asm__ __volatile__(
  99. PPC_ATOMIC_ENTRY_BARRIER
  100. "1: lwarx %0,0,%1 # atomic_inc_return\n\
  101. addic %0,%0,1\n"
  102. PPC405_ERR77(0,%1)
  103. " stwcx. %0,0,%1 \n\
  104. bne- 1b"
  105. PPC_ATOMIC_EXIT_BARRIER
  106. : "=&r" (t)
  107. : "r" (&v->counter)
  108. : "cc", "xer", "memory");
  109. return t;
  110. }
  111. /*
  112. * atomic_inc_and_test - increment and test
  113. * @v: pointer of type atomic_t
  114. *
  115. * Atomically increments @v by 1
  116. * and returns true if the result is zero, or false for all
  117. * other cases.
  118. */
  119. #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
  120. static __inline__ void atomic_dec(atomic_t *v)
  121. {
  122. int t;
  123. __asm__ __volatile__(
  124. "1: lwarx %0,0,%2 # atomic_dec\n\
  125. addic %0,%0,-1\n"
  126. PPC405_ERR77(0,%2)\
  127. " stwcx. %0,0,%2\n\
  128. bne- 1b"
  129. : "=&r" (t), "+m" (v->counter)
  130. : "r" (&v->counter)
  131. : "cc", "xer");
  132. }
  133. static __inline__ int atomic_dec_return(atomic_t *v)
  134. {
  135. int t;
  136. __asm__ __volatile__(
  137. PPC_ATOMIC_ENTRY_BARRIER
  138. "1: lwarx %0,0,%1 # atomic_dec_return\n\
  139. addic %0,%0,-1\n"
  140. PPC405_ERR77(0,%1)
  141. " stwcx. %0,0,%1\n\
  142. bne- 1b"
  143. PPC_ATOMIC_EXIT_BARRIER
  144. : "=&r" (t)
  145. : "r" (&v->counter)
  146. : "cc", "xer", "memory");
  147. return t;
  148. }
  149. #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
  150. #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
  151. /**
  152. * __atomic_add_unless - add unless the number is a given value
  153. * @v: pointer of type atomic_t
  154. * @a: the amount to add to v...
  155. * @u: ...unless v is equal to u.
  156. *
  157. * Atomically adds @a to @v, so long as it was not @u.
  158. * Returns the old value of @v.
  159. */
  160. static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
  161. {
  162. int t;
  163. __asm__ __volatile__ (
  164. PPC_ATOMIC_ENTRY_BARRIER
  165. "1: lwarx %0,0,%1 # __atomic_add_unless\n\
  166. cmpw 0,%0,%3 \n\
  167. beq- 2f \n\
  168. add %0,%2,%0 \n"
  169. PPC405_ERR77(0,%2)
  170. " stwcx. %0,0,%1 \n\
  171. bne- 1b \n"
  172. PPC_ATOMIC_EXIT_BARRIER
  173. " subf %0,%2,%0 \n\
  174. 2:"
  175. : "=&r" (t)
  176. : "r" (&v->counter), "r" (a), "r" (u)
  177. : "cc", "memory");
  178. return t;
  179. }
  180. /**
  181. * atomic_inc_not_zero - increment unless the number is zero
  182. * @v: pointer of type atomic_t
  183. *
  184. * Atomically increments @v by 1, so long as @v is non-zero.
  185. * Returns non-zero if @v was non-zero, and zero otherwise.
  186. */
  187. static __inline__ int atomic_inc_not_zero(atomic_t *v)
  188. {
  189. int t1, t2;
  190. __asm__ __volatile__ (
  191. PPC_ATOMIC_ENTRY_BARRIER
  192. "1: lwarx %0,0,%2 # atomic_inc_not_zero\n\
  193. cmpwi 0,%0,0\n\
  194. beq- 2f\n\
  195. addic %1,%0,1\n"
  196. PPC405_ERR77(0,%2)
  197. " stwcx. %1,0,%2\n\
  198. bne- 1b\n"
  199. PPC_ATOMIC_EXIT_BARRIER
  200. "\n\
  201. 2:"
  202. : "=&r" (t1), "=&r" (t2)
  203. : "r" (&v->counter)
  204. : "cc", "xer", "memory");
  205. return t1;
  206. }
  207. #define atomic_inc_not_zero(v) atomic_inc_not_zero((v))
  208. #define atomic_sub_and_test(a, v) (atomic_sub_return((a), (v)) == 0)
  209. #define atomic_dec_and_test(v) (atomic_dec_return((v)) == 0)
  210. /*
  211. * Atomically test *v and decrement if it is greater than 0.
  212. * The function returns the old value of *v minus 1, even if
  213. * the atomic variable, v, was not decremented.
  214. */
  215. static __inline__ int atomic_dec_if_positive(atomic_t *v)
  216. {
  217. int t;
  218. __asm__ __volatile__(
  219. PPC_ATOMIC_ENTRY_BARRIER
  220. "1: lwarx %0,0,%1 # atomic_dec_if_positive\n\
  221. cmpwi %0,1\n\
  222. addi %0,%0,-1\n\
  223. blt- 2f\n"
  224. PPC405_ERR77(0,%1)
  225. " stwcx. %0,0,%1\n\
  226. bne- 1b"
  227. PPC_ATOMIC_EXIT_BARRIER
  228. "\n\
  229. 2:" : "=&b" (t)
  230. : "r" (&v->counter)
  231. : "cc", "memory");
  232. return t;
  233. }
  234. #define smp_mb__before_atomic_dec() smp_mb()
  235. #define smp_mb__after_atomic_dec() smp_mb()
  236. #define smp_mb__before_atomic_inc() smp_mb()
  237. #define smp_mb__after_atomic_inc() smp_mb()
  238. #ifdef __powerpc64__
  239. #define ATOMIC64_INIT(i) { (i) }
  240. static __inline__ long atomic64_read(const atomic64_t *v)
  241. {
  242. long t;
  243. __asm__ __volatile__("ld%U1%X1 %0,%1" : "=r"(t) : "m"(v->counter));
  244. return t;
  245. }
  246. static __inline__ void atomic64_set(atomic64_t *v, long i)
  247. {
  248. __asm__ __volatile__("std%U0%X0 %1,%0" : "=m"(v->counter) : "r"(i));
  249. }
  250. static __inline__ void atomic64_add(long a, atomic64_t *v)
  251. {
  252. long t;
  253. __asm__ __volatile__(
  254. "1: ldarx %0,0,%3 # atomic64_add\n\
  255. add %0,%2,%0\n\
  256. stdcx. %0,0,%3 \n\
  257. bne- 1b"
  258. : "=&r" (t), "+m" (v->counter)
  259. : "r" (a), "r" (&v->counter)
  260. : "cc");
  261. }
  262. static __inline__ long atomic64_add_return(long a, atomic64_t *v)
  263. {
  264. long t;
  265. __asm__ __volatile__(
  266. PPC_ATOMIC_ENTRY_BARRIER
  267. "1: ldarx %0,0,%2 # atomic64_add_return\n\
  268. add %0,%1,%0\n\
  269. stdcx. %0,0,%2 \n\
  270. bne- 1b"
  271. PPC_ATOMIC_EXIT_BARRIER
  272. : "=&r" (t)
  273. : "r" (a), "r" (&v->counter)
  274. : "cc", "memory");
  275. return t;
  276. }
  277. #define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0)
  278. static __inline__ void atomic64_sub(long a, atomic64_t *v)
  279. {
  280. long t;
  281. __asm__ __volatile__(
  282. "1: ldarx %0,0,%3 # atomic64_sub\n\
  283. subf %0,%2,%0\n\
  284. stdcx. %0,0,%3 \n\
  285. bne- 1b"
  286. : "=&r" (t), "+m" (v->counter)
  287. : "r" (a), "r" (&v->counter)
  288. : "cc");
  289. }
  290. static __inline__ long atomic64_sub_return(long a, atomic64_t *v)
  291. {
  292. long t;
  293. __asm__ __volatile__(
  294. PPC_ATOMIC_ENTRY_BARRIER
  295. "1: ldarx %0,0,%2 # atomic64_sub_return\n\
  296. subf %0,%1,%0\n\
  297. stdcx. %0,0,%2 \n\
  298. bne- 1b"
  299. PPC_ATOMIC_EXIT_BARRIER
  300. : "=&r" (t)
  301. : "r" (a), "r" (&v->counter)
  302. : "cc", "memory");
  303. return t;
  304. }
  305. static __inline__ void atomic64_inc(atomic64_t *v)
  306. {
  307. long t;
  308. __asm__ __volatile__(
  309. "1: ldarx %0,0,%2 # atomic64_inc\n\
  310. addic %0,%0,1\n\
  311. stdcx. %0,0,%2 \n\
  312. bne- 1b"
  313. : "=&r" (t), "+m" (v->counter)
  314. : "r" (&v->counter)
  315. : "cc", "xer");
  316. }
  317. static __inline__ long atomic64_inc_return(atomic64_t *v)
  318. {
  319. long t;
  320. __asm__ __volatile__(
  321. PPC_ATOMIC_ENTRY_BARRIER
  322. "1: ldarx %0,0,%1 # atomic64_inc_return\n\
  323. addic %0,%0,1\n\
  324. stdcx. %0,0,%1 \n\
  325. bne- 1b"
  326. PPC_ATOMIC_EXIT_BARRIER
  327. : "=&r" (t)
  328. : "r" (&v->counter)
  329. : "cc", "xer", "memory");
  330. return t;
  331. }
  332. /*
  333. * atomic64_inc_and_test - increment and test
  334. * @v: pointer of type atomic64_t
  335. *
  336. * Atomically increments @v by 1
  337. * and returns true if the result is zero, or false for all
  338. * other cases.
  339. */
  340. #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
  341. static __inline__ void atomic64_dec(atomic64_t *v)
  342. {
  343. long t;
  344. __asm__ __volatile__(
  345. "1: ldarx %0,0,%2 # atomic64_dec\n\
  346. addic %0,%0,-1\n\
  347. stdcx. %0,0,%2\n\
  348. bne- 1b"
  349. : "=&r" (t), "+m" (v->counter)
  350. : "r" (&v->counter)
  351. : "cc", "xer");
  352. }
  353. static __inline__ long atomic64_dec_return(atomic64_t *v)
  354. {
  355. long t;
  356. __asm__ __volatile__(
  357. PPC_ATOMIC_ENTRY_BARRIER
  358. "1: ldarx %0,0,%1 # atomic64_dec_return\n\
  359. addic %0,%0,-1\n\
  360. stdcx. %0,0,%1\n\
  361. bne- 1b"
  362. PPC_ATOMIC_EXIT_BARRIER
  363. : "=&r" (t)
  364. : "r" (&v->counter)
  365. : "cc", "xer", "memory");
  366. return t;
  367. }
  368. #define atomic64_sub_and_test(a, v) (atomic64_sub_return((a), (v)) == 0)
  369. #define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0)
  370. /*
  371. * Atomically test *v and decrement if it is greater than 0.
  372. * The function returns the old value of *v minus 1.
  373. */
  374. static __inline__ long atomic64_dec_if_positive(atomic64_t *v)
  375. {
  376. long t;
  377. __asm__ __volatile__(
  378. PPC_ATOMIC_ENTRY_BARRIER
  379. "1: ldarx %0,0,%1 # atomic64_dec_if_positive\n\
  380. addic. %0,%0,-1\n\
  381. blt- 2f\n\
  382. stdcx. %0,0,%1\n\
  383. bne- 1b"
  384. PPC_ATOMIC_EXIT_BARRIER
  385. "\n\
  386. 2:" : "=&r" (t)
  387. : "r" (&v->counter)
  388. : "cc", "xer", "memory");
  389. return t;
  390. }
  391. #define atomic64_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
  392. #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
  393. /**
  394. * atomic64_add_unless - add unless the number is a given value
  395. * @v: pointer of type atomic64_t
  396. * @a: the amount to add to v...
  397. * @u: ...unless v is equal to u.
  398. *
  399. * Atomically adds @a to @v, so long as it was not @u.
  400. * Returns the old value of @v.
  401. */
  402. static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
  403. {
  404. long t;
  405. __asm__ __volatile__ (
  406. PPC_ATOMIC_ENTRY_BARRIER
  407. "1: ldarx %0,0,%1 # __atomic_add_unless\n\
  408. cmpd 0,%0,%3 \n\
  409. beq- 2f \n\
  410. add %0,%2,%0 \n"
  411. " stdcx. %0,0,%1 \n\
  412. bne- 1b \n"
  413. PPC_ATOMIC_EXIT_BARRIER
  414. " subf %0,%2,%0 \n\
  415. 2:"
  416. : "=&r" (t)
  417. : "r" (&v->counter), "r" (a), "r" (u)
  418. : "cc", "memory");
  419. return t != u;
  420. }
  421. /**
  422. * atomic_inc64_not_zero - increment unless the number is zero
  423. * @v: pointer of type atomic64_t
  424. *
  425. * Atomically increments @v by 1, so long as @v is non-zero.
  426. * Returns non-zero if @v was non-zero, and zero otherwise.
  427. */
  428. static __inline__ long atomic64_inc_not_zero(atomic64_t *v)
  429. {
  430. long t1, t2;
  431. __asm__ __volatile__ (
  432. PPC_ATOMIC_ENTRY_BARRIER
  433. "1: ldarx %0,0,%2 # atomic64_inc_not_zero\n\
  434. cmpdi 0,%0,0\n\
  435. beq- 2f\n\
  436. addic %1,%0,1\n\
  437. stdcx. %1,0,%2\n\
  438. bne- 1b\n"
  439. PPC_ATOMIC_EXIT_BARRIER
  440. "\n\
  441. 2:"
  442. : "=&r" (t1), "=&r" (t2)
  443. : "r" (&v->counter)
  444. : "cc", "xer", "memory");
  445. return t1;
  446. }
  447. #endif /* __powerpc64__ */
  448. #endif /* __KERNEL__ */
  449. #endif /* _ASM_POWERPC_ATOMIC_H_ */