percpu.h 26 KB

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  1. #ifndef __LINUX_PERCPU_H
  2. #define __LINUX_PERCPU_H
  3. #include <linux/preempt.h>
  4. #include <linux/smp.h>
  5. #include <linux/cpumask.h>
  6. #include <linux/pfn.h>
  7. #include <linux/init.h>
  8. #include <asm/percpu.h>
  9. /* enough to cover all DEFINE_PER_CPUs in modules */
  10. #ifdef CONFIG_MODULES
  11. #define PERCPU_MODULE_RESERVE (8 << 10)
  12. #else
  13. #define PERCPU_MODULE_RESERVE 0
  14. #endif
  15. #ifndef PERCPU_ENOUGH_ROOM
  16. #define PERCPU_ENOUGH_ROOM \
  17. (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \
  18. PERCPU_MODULE_RESERVE)
  19. #endif
  20. /*
  21. * Must be an lvalue. Since @var must be a simple identifier,
  22. * we force a syntax error here if it isn't.
  23. */
  24. #define get_cpu_var(var) (*({ \
  25. preempt_disable(); \
  26. &__get_cpu_var(var); }))
  27. /*
  28. * The weird & is necessary because sparse considers (void)(var) to be
  29. * a direct dereference of percpu variable (var).
  30. */
  31. #define put_cpu_var(var) do { \
  32. (void)&(var); \
  33. preempt_enable(); \
  34. } while (0)
  35. #define get_cpu_ptr(var) ({ \
  36. preempt_disable(); \
  37. this_cpu_ptr(var); })
  38. #define put_cpu_ptr(var) do { \
  39. (void)(var); \
  40. preempt_enable(); \
  41. } while (0)
  42. /* minimum unit size, also is the maximum supported allocation size */
  43. #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10)
  44. /*
  45. * Percpu allocator can serve percpu allocations before slab is
  46. * initialized which allows slab to depend on the percpu allocator.
  47. * The following two parameters decide how much resource to
  48. * preallocate for this. Keep PERCPU_DYNAMIC_RESERVE equal to or
  49. * larger than PERCPU_DYNAMIC_EARLY_SIZE.
  50. */
  51. #define PERCPU_DYNAMIC_EARLY_SLOTS 128
  52. #define PERCPU_DYNAMIC_EARLY_SIZE (12 << 10)
  53. /*
  54. * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
  55. * back on the first chunk for dynamic percpu allocation if arch is
  56. * manually allocating and mapping it for faster access (as a part of
  57. * large page mapping for example).
  58. *
  59. * The following values give between one and two pages of free space
  60. * after typical minimal boot (2-way SMP, single disk and NIC) with
  61. * both defconfig and a distro config on x86_64 and 32. More
  62. * intelligent way to determine this would be nice.
  63. */
  64. #if BITS_PER_LONG > 32
  65. #define PERCPU_DYNAMIC_RESERVE (20 << 10)
  66. #else
  67. #define PERCPU_DYNAMIC_RESERVE (12 << 10)
  68. #endif
  69. extern void *pcpu_base_addr;
  70. extern const unsigned long *pcpu_unit_offsets;
  71. struct pcpu_group_info {
  72. int nr_units; /* aligned # of units */
  73. unsigned long base_offset; /* base address offset */
  74. unsigned int *cpu_map; /* unit->cpu map, empty
  75. * entries contain NR_CPUS */
  76. };
  77. struct pcpu_alloc_info {
  78. size_t static_size;
  79. size_t reserved_size;
  80. size_t dyn_size;
  81. size_t unit_size;
  82. size_t atom_size;
  83. size_t alloc_size;
  84. size_t __ai_size; /* internal, don't use */
  85. int nr_groups; /* 0 if grouping unnecessary */
  86. struct pcpu_group_info groups[];
  87. };
  88. enum pcpu_fc {
  89. PCPU_FC_AUTO,
  90. PCPU_FC_EMBED,
  91. PCPU_FC_PAGE,
  92. PCPU_FC_NR,
  93. };
  94. extern const char *pcpu_fc_names[PCPU_FC_NR];
  95. extern enum pcpu_fc pcpu_chosen_fc;
  96. typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
  97. size_t align);
  98. typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
  99. typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
  100. typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
  101. extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
  102. int nr_units);
  103. extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
  104. extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
  105. void *base_addr);
  106. #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
  107. extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
  108. size_t atom_size,
  109. pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
  110. pcpu_fc_alloc_fn_t alloc_fn,
  111. pcpu_fc_free_fn_t free_fn);
  112. #endif
  113. #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
  114. extern int __init pcpu_page_first_chunk(size_t reserved_size,
  115. pcpu_fc_alloc_fn_t alloc_fn,
  116. pcpu_fc_free_fn_t free_fn,
  117. pcpu_fc_populate_pte_fn_t populate_pte_fn);
  118. #endif
  119. /*
  120. * Use this to get to a cpu's version of the per-cpu object
  121. * dynamically allocated. Non-atomic access to the current CPU's
  122. * version should probably be combined with get_cpu()/put_cpu().
  123. */
  124. #ifdef CONFIG_SMP
  125. #define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
  126. #else
  127. #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })
  128. #endif
  129. extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
  130. extern bool is_kernel_percpu_address(unsigned long addr);
  131. #if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
  132. extern void __init setup_per_cpu_areas(void);
  133. #endif
  134. extern void __init percpu_init_late(void);
  135. extern void __percpu *__alloc_percpu(size_t size, size_t align);
  136. extern void free_percpu(void __percpu *__pdata);
  137. extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
  138. #define alloc_percpu(type) \
  139. (typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
  140. /*
  141. * Optional methods for optimized non-lvalue per-cpu variable access.
  142. *
  143. * @var can be a percpu variable or a field of it and its size should
  144. * equal char, int or long. percpu_read() evaluates to a lvalue and
  145. * all others to void.
  146. *
  147. * These operations are guaranteed to be atomic w.r.t. preemption.
  148. * The generic versions use plain get/put_cpu_var(). Archs are
  149. * encouraged to implement single-instruction alternatives which don't
  150. * require preemption protection.
  151. */
  152. #ifndef percpu_read
  153. # define percpu_read(var) \
  154. ({ \
  155. typeof(var) *pr_ptr__ = &(var); \
  156. typeof(var) pr_ret__; \
  157. pr_ret__ = get_cpu_var(*pr_ptr__); \
  158. put_cpu_var(*pr_ptr__); \
  159. pr_ret__; \
  160. })
  161. #endif
  162. #define __percpu_generic_to_op(var, val, op) \
  163. do { \
  164. typeof(var) *pgto_ptr__ = &(var); \
  165. get_cpu_var(*pgto_ptr__) op val; \
  166. put_cpu_var(*pgto_ptr__); \
  167. } while (0)
  168. #ifndef percpu_write
  169. # define percpu_write(var, val) __percpu_generic_to_op(var, (val), =)
  170. #endif
  171. #ifndef percpu_add
  172. # define percpu_add(var, val) __percpu_generic_to_op(var, (val), +=)
  173. #endif
  174. #ifndef percpu_sub
  175. # define percpu_sub(var, val) __percpu_generic_to_op(var, (val), -=)
  176. #endif
  177. #ifndef percpu_and
  178. # define percpu_and(var, val) __percpu_generic_to_op(var, (val), &=)
  179. #endif
  180. #ifndef percpu_or
  181. # define percpu_or(var, val) __percpu_generic_to_op(var, (val), |=)
  182. #endif
  183. #ifndef percpu_xor
  184. # define percpu_xor(var, val) __percpu_generic_to_op(var, (val), ^=)
  185. #endif
  186. /*
  187. * Branching function to split up a function into a set of functions that
  188. * are called for different scalar sizes of the objects handled.
  189. */
  190. extern void __bad_size_call_parameter(void);
  191. #define __pcpu_size_call_return(stem, variable) \
  192. ({ typeof(variable) pscr_ret__; \
  193. __verify_pcpu_ptr(&(variable)); \
  194. switch(sizeof(variable)) { \
  195. case 1: pscr_ret__ = stem##1(variable);break; \
  196. case 2: pscr_ret__ = stem##2(variable);break; \
  197. case 4: pscr_ret__ = stem##4(variable);break; \
  198. case 8: pscr_ret__ = stem##8(variable);break; \
  199. default: \
  200. __bad_size_call_parameter();break; \
  201. } \
  202. pscr_ret__; \
  203. })
  204. #define __pcpu_size_call_return2(stem, variable, ...) \
  205. ({ \
  206. typeof(variable) pscr2_ret__; \
  207. __verify_pcpu_ptr(&(variable)); \
  208. switch(sizeof(variable)) { \
  209. case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \
  210. case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break; \
  211. case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break; \
  212. case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break; \
  213. default: \
  214. __bad_size_call_parameter(); break; \
  215. } \
  216. pscr2_ret__; \
  217. })
  218. #define __pcpu_size_call(stem, variable, ...) \
  219. do { \
  220. __verify_pcpu_ptr(&(variable)); \
  221. switch(sizeof(variable)) { \
  222. case 1: stem##1(variable, __VA_ARGS__);break; \
  223. case 2: stem##2(variable, __VA_ARGS__);break; \
  224. case 4: stem##4(variable, __VA_ARGS__);break; \
  225. case 8: stem##8(variable, __VA_ARGS__);break; \
  226. default: \
  227. __bad_size_call_parameter();break; \
  228. } \
  229. } while (0)
  230. /*
  231. * Optimized manipulation for memory allocated through the per cpu
  232. * allocator or for addresses of per cpu variables.
  233. *
  234. * These operation guarantee exclusivity of access for other operations
  235. * on the *same* processor. The assumption is that per cpu data is only
  236. * accessed by a single processor instance (the current one).
  237. *
  238. * The first group is used for accesses that must be done in a
  239. * preemption safe way since we know that the context is not preempt
  240. * safe. Interrupts may occur. If the interrupt modifies the variable
  241. * too then RMW actions will not be reliable.
  242. *
  243. * The arch code can provide optimized functions in two ways:
  244. *
  245. * 1. Override the function completely. F.e. define this_cpu_add().
  246. * The arch must then ensure that the various scalar format passed
  247. * are handled correctly.
  248. *
  249. * 2. Provide functions for certain scalar sizes. F.e. provide
  250. * this_cpu_add_2() to provide per cpu atomic operations for 2 byte
  251. * sized RMW actions. If arch code does not provide operations for
  252. * a scalar size then the fallback in the generic code will be
  253. * used.
  254. */
  255. #define _this_cpu_generic_read(pcp) \
  256. ({ typeof(pcp) ret__; \
  257. preempt_disable(); \
  258. ret__ = *this_cpu_ptr(&(pcp)); \
  259. preempt_enable(); \
  260. ret__; \
  261. })
  262. #ifndef this_cpu_read
  263. # ifndef this_cpu_read_1
  264. # define this_cpu_read_1(pcp) _this_cpu_generic_read(pcp)
  265. # endif
  266. # ifndef this_cpu_read_2
  267. # define this_cpu_read_2(pcp) _this_cpu_generic_read(pcp)
  268. # endif
  269. # ifndef this_cpu_read_4
  270. # define this_cpu_read_4(pcp) _this_cpu_generic_read(pcp)
  271. # endif
  272. # ifndef this_cpu_read_8
  273. # define this_cpu_read_8(pcp) _this_cpu_generic_read(pcp)
  274. # endif
  275. # define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp))
  276. #endif
  277. #define _this_cpu_generic_to_op(pcp, val, op) \
  278. do { \
  279. preempt_disable(); \
  280. *__this_cpu_ptr(&(pcp)) op val; \
  281. preempt_enable(); \
  282. } while (0)
  283. #ifndef this_cpu_write
  284. # ifndef this_cpu_write_1
  285. # define this_cpu_write_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
  286. # endif
  287. # ifndef this_cpu_write_2
  288. # define this_cpu_write_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
  289. # endif
  290. # ifndef this_cpu_write_4
  291. # define this_cpu_write_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
  292. # endif
  293. # ifndef this_cpu_write_8
  294. # define this_cpu_write_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
  295. # endif
  296. # define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val))
  297. #endif
  298. #ifndef this_cpu_add
  299. # ifndef this_cpu_add_1
  300. # define this_cpu_add_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
  301. # endif
  302. # ifndef this_cpu_add_2
  303. # define this_cpu_add_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
  304. # endif
  305. # ifndef this_cpu_add_4
  306. # define this_cpu_add_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
  307. # endif
  308. # ifndef this_cpu_add_8
  309. # define this_cpu_add_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
  310. # endif
  311. # define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val))
  312. #endif
  313. #ifndef this_cpu_sub
  314. # define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(val))
  315. #endif
  316. #ifndef this_cpu_inc
  317. # define this_cpu_inc(pcp) this_cpu_add((pcp), 1)
  318. #endif
  319. #ifndef this_cpu_dec
  320. # define this_cpu_dec(pcp) this_cpu_sub((pcp), 1)
  321. #endif
  322. #ifndef this_cpu_and
  323. # ifndef this_cpu_and_1
  324. # define this_cpu_and_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
  325. # endif
  326. # ifndef this_cpu_and_2
  327. # define this_cpu_and_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
  328. # endif
  329. # ifndef this_cpu_and_4
  330. # define this_cpu_and_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
  331. # endif
  332. # ifndef this_cpu_and_8
  333. # define this_cpu_and_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
  334. # endif
  335. # define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val))
  336. #endif
  337. #ifndef this_cpu_or
  338. # ifndef this_cpu_or_1
  339. # define this_cpu_or_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
  340. # endif
  341. # ifndef this_cpu_or_2
  342. # define this_cpu_or_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
  343. # endif
  344. # ifndef this_cpu_or_4
  345. # define this_cpu_or_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
  346. # endif
  347. # ifndef this_cpu_or_8
  348. # define this_cpu_or_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
  349. # endif
  350. # define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
  351. #endif
  352. #ifndef this_cpu_xor
  353. # ifndef this_cpu_xor_1
  354. # define this_cpu_xor_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
  355. # endif
  356. # ifndef this_cpu_xor_2
  357. # define this_cpu_xor_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
  358. # endif
  359. # ifndef this_cpu_xor_4
  360. # define this_cpu_xor_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
  361. # endif
  362. # ifndef this_cpu_xor_8
  363. # define this_cpu_xor_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
  364. # endif
  365. # define this_cpu_xor(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
  366. #endif
  367. #define _this_cpu_generic_add_return(pcp, val) \
  368. ({ \
  369. typeof(pcp) ret__; \
  370. preempt_disable(); \
  371. __this_cpu_add(pcp, val); \
  372. ret__ = __this_cpu_read(pcp); \
  373. preempt_enable(); \
  374. ret__; \
  375. })
  376. #ifndef this_cpu_add_return
  377. # ifndef this_cpu_add_return_1
  378. # define this_cpu_add_return_1(pcp, val) _this_cpu_generic_add_return(pcp, val)
  379. # endif
  380. # ifndef this_cpu_add_return_2
  381. # define this_cpu_add_return_2(pcp, val) _this_cpu_generic_add_return(pcp, val)
  382. # endif
  383. # ifndef this_cpu_add_return_4
  384. # define this_cpu_add_return_4(pcp, val) _this_cpu_generic_add_return(pcp, val)
  385. # endif
  386. # ifndef this_cpu_add_return_8
  387. # define this_cpu_add_return_8(pcp, val) _this_cpu_generic_add_return(pcp, val)
  388. # endif
  389. # define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
  390. #endif
  391. #define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(val))
  392. #define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1)
  393. #define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1)
  394. #define _this_cpu_generic_xchg(pcp, nval) \
  395. ({ typeof(pcp) ret__; \
  396. preempt_disable(); \
  397. ret__ = __this_cpu_read(pcp); \
  398. __this_cpu_write(pcp, nval); \
  399. preempt_enable(); \
  400. ret__; \
  401. })
  402. #ifndef this_cpu_xchg
  403. # ifndef this_cpu_xchg_1
  404. # define this_cpu_xchg_1(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
  405. # endif
  406. # ifndef this_cpu_xchg_2
  407. # define this_cpu_xchg_2(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
  408. # endif
  409. # ifndef this_cpu_xchg_4
  410. # define this_cpu_xchg_4(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
  411. # endif
  412. # ifndef this_cpu_xchg_8
  413. # define this_cpu_xchg_8(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
  414. # endif
  415. # define this_cpu_xchg(pcp, nval) \
  416. __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval)
  417. #endif
  418. #define _this_cpu_generic_cmpxchg(pcp, oval, nval) \
  419. ({ typeof(pcp) ret__; \
  420. preempt_disable(); \
  421. ret__ = __this_cpu_read(pcp); \
  422. if (ret__ == (oval)) \
  423. __this_cpu_write(pcp, nval); \
  424. preempt_enable(); \
  425. ret__; \
  426. })
  427. #ifndef this_cpu_cmpxchg
  428. # ifndef this_cpu_cmpxchg_1
  429. # define this_cpu_cmpxchg_1(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
  430. # endif
  431. # ifndef this_cpu_cmpxchg_2
  432. # define this_cpu_cmpxchg_2(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
  433. # endif
  434. # ifndef this_cpu_cmpxchg_4
  435. # define this_cpu_cmpxchg_4(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
  436. # endif
  437. # ifndef this_cpu_cmpxchg_8
  438. # define this_cpu_cmpxchg_8(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
  439. # endif
  440. # define this_cpu_cmpxchg(pcp, oval, nval) \
  441. __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
  442. #endif
  443. /*
  444. * Generic percpu operations that do not require preemption handling.
  445. * Either we do not care about races or the caller has the
  446. * responsibility of handling preemptions issues. Arch code can still
  447. * override these instructions since the arch per cpu code may be more
  448. * efficient and may actually get race freeness for free (that is the
  449. * case for x86 for example).
  450. *
  451. * If there is no other protection through preempt disable and/or
  452. * disabling interupts then one of these RMW operations can show unexpected
  453. * behavior because the execution thread was rescheduled on another processor
  454. * or an interrupt occurred and the same percpu variable was modified from
  455. * the interrupt context.
  456. */
  457. #ifndef __this_cpu_read
  458. # ifndef __this_cpu_read_1
  459. # define __this_cpu_read_1(pcp) (*__this_cpu_ptr(&(pcp)))
  460. # endif
  461. # ifndef __this_cpu_read_2
  462. # define __this_cpu_read_2(pcp) (*__this_cpu_ptr(&(pcp)))
  463. # endif
  464. # ifndef __this_cpu_read_4
  465. # define __this_cpu_read_4(pcp) (*__this_cpu_ptr(&(pcp)))
  466. # endif
  467. # ifndef __this_cpu_read_8
  468. # define __this_cpu_read_8(pcp) (*__this_cpu_ptr(&(pcp)))
  469. # endif
  470. # define __this_cpu_read(pcp) __pcpu_size_call_return(__this_cpu_read_, (pcp))
  471. #endif
  472. #define __this_cpu_generic_to_op(pcp, val, op) \
  473. do { \
  474. *__this_cpu_ptr(&(pcp)) op val; \
  475. } while (0)
  476. #ifndef __this_cpu_write
  477. # ifndef __this_cpu_write_1
  478. # define __this_cpu_write_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
  479. # endif
  480. # ifndef __this_cpu_write_2
  481. # define __this_cpu_write_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
  482. # endif
  483. # ifndef __this_cpu_write_4
  484. # define __this_cpu_write_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
  485. # endif
  486. # ifndef __this_cpu_write_8
  487. # define __this_cpu_write_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
  488. # endif
  489. # define __this_cpu_write(pcp, val) __pcpu_size_call(__this_cpu_write_, (pcp), (val))
  490. #endif
  491. #ifndef __this_cpu_add
  492. # ifndef __this_cpu_add_1
  493. # define __this_cpu_add_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
  494. # endif
  495. # ifndef __this_cpu_add_2
  496. # define __this_cpu_add_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
  497. # endif
  498. # ifndef __this_cpu_add_4
  499. # define __this_cpu_add_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
  500. # endif
  501. # ifndef __this_cpu_add_8
  502. # define __this_cpu_add_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
  503. # endif
  504. # define __this_cpu_add(pcp, val) __pcpu_size_call(__this_cpu_add_, (pcp), (val))
  505. #endif
  506. #ifndef __this_cpu_sub
  507. # define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(val))
  508. #endif
  509. #ifndef __this_cpu_inc
  510. # define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1)
  511. #endif
  512. #ifndef __this_cpu_dec
  513. # define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1)
  514. #endif
  515. #ifndef __this_cpu_and
  516. # ifndef __this_cpu_and_1
  517. # define __this_cpu_and_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
  518. # endif
  519. # ifndef __this_cpu_and_2
  520. # define __this_cpu_and_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
  521. # endif
  522. # ifndef __this_cpu_and_4
  523. # define __this_cpu_and_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
  524. # endif
  525. # ifndef __this_cpu_and_8
  526. # define __this_cpu_and_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
  527. # endif
  528. # define __this_cpu_and(pcp, val) __pcpu_size_call(__this_cpu_and_, (pcp), (val))
  529. #endif
  530. #ifndef __this_cpu_or
  531. # ifndef __this_cpu_or_1
  532. # define __this_cpu_or_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
  533. # endif
  534. # ifndef __this_cpu_or_2
  535. # define __this_cpu_or_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
  536. # endif
  537. # ifndef __this_cpu_or_4
  538. # define __this_cpu_or_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
  539. # endif
  540. # ifndef __this_cpu_or_8
  541. # define __this_cpu_or_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
  542. # endif
  543. # define __this_cpu_or(pcp, val) __pcpu_size_call(__this_cpu_or_, (pcp), (val))
  544. #endif
  545. #ifndef __this_cpu_xor
  546. # ifndef __this_cpu_xor_1
  547. # define __this_cpu_xor_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
  548. # endif
  549. # ifndef __this_cpu_xor_2
  550. # define __this_cpu_xor_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
  551. # endif
  552. # ifndef __this_cpu_xor_4
  553. # define __this_cpu_xor_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
  554. # endif
  555. # ifndef __this_cpu_xor_8
  556. # define __this_cpu_xor_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
  557. # endif
  558. # define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
  559. #endif
  560. #define __this_cpu_generic_add_return(pcp, val) \
  561. ({ \
  562. __this_cpu_add(pcp, val); \
  563. __this_cpu_read(pcp); \
  564. })
  565. #ifndef __this_cpu_add_return
  566. # ifndef __this_cpu_add_return_1
  567. # define __this_cpu_add_return_1(pcp, val) __this_cpu_generic_add_return(pcp, val)
  568. # endif
  569. # ifndef __this_cpu_add_return_2
  570. # define __this_cpu_add_return_2(pcp, val) __this_cpu_generic_add_return(pcp, val)
  571. # endif
  572. # ifndef __this_cpu_add_return_4
  573. # define __this_cpu_add_return_4(pcp, val) __this_cpu_generic_add_return(pcp, val)
  574. # endif
  575. # ifndef __this_cpu_add_return_8
  576. # define __this_cpu_add_return_8(pcp, val) __this_cpu_generic_add_return(pcp, val)
  577. # endif
  578. # define __this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
  579. #endif
  580. #define __this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(val))
  581. #define __this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1)
  582. #define __this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1)
  583. #define __this_cpu_generic_xchg(pcp, nval) \
  584. ({ typeof(pcp) ret__; \
  585. ret__ = __this_cpu_read(pcp); \
  586. __this_cpu_write(pcp, nval); \
  587. ret__; \
  588. })
  589. #ifndef __this_cpu_xchg
  590. # ifndef __this_cpu_xchg_1
  591. # define __this_cpu_xchg_1(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
  592. # endif
  593. # ifndef __this_cpu_xchg_2
  594. # define __this_cpu_xchg_2(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
  595. # endif
  596. # ifndef __this_cpu_xchg_4
  597. # define __this_cpu_xchg_4(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
  598. # endif
  599. # ifndef __this_cpu_xchg_8
  600. # define __this_cpu_xchg_8(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
  601. # endif
  602. # define __this_cpu_xchg(pcp, nval) \
  603. __pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval)
  604. #endif
  605. #define __this_cpu_generic_cmpxchg(pcp, oval, nval) \
  606. ({ \
  607. typeof(pcp) ret__; \
  608. ret__ = __this_cpu_read(pcp); \
  609. if (ret__ == (oval)) \
  610. __this_cpu_write(pcp, nval); \
  611. ret__; \
  612. })
  613. #ifndef __this_cpu_cmpxchg
  614. # ifndef __this_cpu_cmpxchg_1
  615. # define __this_cpu_cmpxchg_1(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
  616. # endif
  617. # ifndef __this_cpu_cmpxchg_2
  618. # define __this_cpu_cmpxchg_2(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
  619. # endif
  620. # ifndef __this_cpu_cmpxchg_4
  621. # define __this_cpu_cmpxchg_4(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
  622. # endif
  623. # ifndef __this_cpu_cmpxchg_8
  624. # define __this_cpu_cmpxchg_8(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
  625. # endif
  626. # define __this_cpu_cmpxchg(pcp, oval, nval) \
  627. __pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval)
  628. #endif
  629. /*
  630. * IRQ safe versions of the per cpu RMW operations. Note that these operations
  631. * are *not* safe against modification of the same variable from another
  632. * processors (which one gets when using regular atomic operations)
  633. * They are guaranteed to be atomic vs. local interrupts and
  634. * preemption only.
  635. */
  636. #define irqsafe_cpu_generic_to_op(pcp, val, op) \
  637. do { \
  638. unsigned long flags; \
  639. local_irq_save(flags); \
  640. *__this_cpu_ptr(&(pcp)) op val; \
  641. local_irq_restore(flags); \
  642. } while (0)
  643. #ifndef irqsafe_cpu_add
  644. # ifndef irqsafe_cpu_add_1
  645. # define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
  646. # endif
  647. # ifndef irqsafe_cpu_add_2
  648. # define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
  649. # endif
  650. # ifndef irqsafe_cpu_add_4
  651. # define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
  652. # endif
  653. # ifndef irqsafe_cpu_add_8
  654. # define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
  655. # endif
  656. # define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val))
  657. #endif
  658. #ifndef irqsafe_cpu_sub
  659. # define irqsafe_cpu_sub(pcp, val) irqsafe_cpu_add((pcp), -(val))
  660. #endif
  661. #ifndef irqsafe_cpu_inc
  662. # define irqsafe_cpu_inc(pcp) irqsafe_cpu_add((pcp), 1)
  663. #endif
  664. #ifndef irqsafe_cpu_dec
  665. # define irqsafe_cpu_dec(pcp) irqsafe_cpu_sub((pcp), 1)
  666. #endif
  667. #ifndef irqsafe_cpu_and
  668. # ifndef irqsafe_cpu_and_1
  669. # define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
  670. # endif
  671. # ifndef irqsafe_cpu_and_2
  672. # define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
  673. # endif
  674. # ifndef irqsafe_cpu_and_4
  675. # define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
  676. # endif
  677. # ifndef irqsafe_cpu_and_8
  678. # define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
  679. # endif
  680. # define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val))
  681. #endif
  682. #ifndef irqsafe_cpu_or
  683. # ifndef irqsafe_cpu_or_1
  684. # define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
  685. # endif
  686. # ifndef irqsafe_cpu_or_2
  687. # define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
  688. # endif
  689. # ifndef irqsafe_cpu_or_4
  690. # define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
  691. # endif
  692. # ifndef irqsafe_cpu_or_8
  693. # define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
  694. # endif
  695. # define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val))
  696. #endif
  697. #ifndef irqsafe_cpu_xor
  698. # ifndef irqsafe_cpu_xor_1
  699. # define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
  700. # endif
  701. # ifndef irqsafe_cpu_xor_2
  702. # define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
  703. # endif
  704. # ifndef irqsafe_cpu_xor_4
  705. # define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
  706. # endif
  707. # ifndef irqsafe_cpu_xor_8
  708. # define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
  709. # endif
  710. # define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val))
  711. #endif
  712. #define irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) \
  713. ({ \
  714. typeof(pcp) ret__; \
  715. unsigned long flags; \
  716. local_irq_save(flags); \
  717. ret__ = __this_cpu_read(pcp); \
  718. if (ret__ == (oval)) \
  719. __this_cpu_write(pcp, nval); \
  720. local_irq_restore(flags); \
  721. ret__; \
  722. })
  723. #ifndef irqsafe_cpu_cmpxchg
  724. # ifndef irqsafe_cpu_cmpxchg_1
  725. # define irqsafe_cpu_cmpxchg_1(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
  726. # endif
  727. # ifndef irqsafe_cpu_cmpxchg_2
  728. # define irqsafe_cpu_cmpxchg_2(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
  729. # endif
  730. # ifndef irqsafe_cpu_cmpxchg_4
  731. # define irqsafe_cpu_cmpxchg_4(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
  732. # endif
  733. # ifndef irqsafe_cpu_cmpxchg_8
  734. # define irqsafe_cpu_cmpxchg_8(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
  735. # endif
  736. # define irqsafe_cpu_cmpxchg(pcp, oval, nval) \
  737. __pcpu_size_call_return2(irqsafe_cpu_cmpxchg_, (pcp), oval, nval)
  738. #endif
  739. #endif /* __LINUX_PERCPU_H */