percpu.h 27 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.
  148. * The generic versions disable interrupts. Archs are
  149. * encouraged to implement single-instruction alternatives which don't
  150. * require 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. /*
  219. * Special handling for cmpxchg_double. cmpxchg_double is passed two
  220. * percpu variables. The first has to be aligned to a double word
  221. * boundary and the second has to follow directly thereafter.
  222. * We enforce this on all architectures even if they don't support
  223. * a double cmpxchg instruction, since it's a cheap requirement, and it
  224. * avoids breaking the requirement for architectures with the instruction.
  225. */
  226. #define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \
  227. ({ \
  228. bool pdcrb_ret__; \
  229. __verify_pcpu_ptr(&pcp1); \
  230. BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \
  231. VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1))); \
  232. VM_BUG_ON((unsigned long)(&pcp2) != \
  233. (unsigned long)(&pcp1) + sizeof(pcp1)); \
  234. switch(sizeof(pcp1)) { \
  235. case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \
  236. case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \
  237. case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \
  238. case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \
  239. default: \
  240. __bad_size_call_parameter(); break; \
  241. } \
  242. pdcrb_ret__; \
  243. })
  244. #define __pcpu_size_call(stem, variable, ...) \
  245. do { \
  246. __verify_pcpu_ptr(&(variable)); \
  247. switch(sizeof(variable)) { \
  248. case 1: stem##1(variable, __VA_ARGS__);break; \
  249. case 2: stem##2(variable, __VA_ARGS__);break; \
  250. case 4: stem##4(variable, __VA_ARGS__);break; \
  251. case 8: stem##8(variable, __VA_ARGS__);break; \
  252. default: \
  253. __bad_size_call_parameter();break; \
  254. } \
  255. } while (0)
  256. /*
  257. * Optimized manipulation for memory allocated through the per cpu
  258. * allocator or for addresses of per cpu variables.
  259. *
  260. * These operation guarantee exclusivity of access for other operations
  261. * on the *same* processor. The assumption is that per cpu data is only
  262. * accessed by a single processor instance (the current one).
  263. *
  264. * The first group is used for accesses that must be done in a
  265. * preemption safe way since we know that the context is not preempt
  266. * safe. Interrupts may occur. If the interrupt modifies the variable
  267. * too then RMW actions will not be reliable.
  268. *
  269. * The arch code can provide optimized functions in two ways:
  270. *
  271. * 1. Override the function completely. F.e. define this_cpu_add().
  272. * The arch must then ensure that the various scalar format passed
  273. * are handled correctly.
  274. *
  275. * 2. Provide functions for certain scalar sizes. F.e. provide
  276. * this_cpu_add_2() to provide per cpu atomic operations for 2 byte
  277. * sized RMW actions. If arch code does not provide operations for
  278. * a scalar size then the fallback in the generic code will be
  279. * used.
  280. */
  281. #define _this_cpu_generic_read(pcp) \
  282. ({ typeof(pcp) ret__; \
  283. preempt_disable(); \
  284. ret__ = *this_cpu_ptr(&(pcp)); \
  285. preempt_enable(); \
  286. ret__; \
  287. })
  288. #ifndef this_cpu_read
  289. # ifndef this_cpu_read_1
  290. # define this_cpu_read_1(pcp) _this_cpu_generic_read(pcp)
  291. # endif
  292. # ifndef this_cpu_read_2
  293. # define this_cpu_read_2(pcp) _this_cpu_generic_read(pcp)
  294. # endif
  295. # ifndef this_cpu_read_4
  296. # define this_cpu_read_4(pcp) _this_cpu_generic_read(pcp)
  297. # endif
  298. # ifndef this_cpu_read_8
  299. # define this_cpu_read_8(pcp) _this_cpu_generic_read(pcp)
  300. # endif
  301. # define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp))
  302. #endif
  303. #define _this_cpu_generic_to_op(pcp, val, op) \
  304. do { \
  305. unsigned long flags; \
  306. raw_local_irq_save(flags); \
  307. *__this_cpu_ptr(&(pcp)) op val; \
  308. raw_local_irq_restore(flags); \
  309. } while (0)
  310. #ifndef this_cpu_write
  311. # ifndef this_cpu_write_1
  312. # define this_cpu_write_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
  313. # endif
  314. # ifndef this_cpu_write_2
  315. # define this_cpu_write_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
  316. # endif
  317. # ifndef this_cpu_write_4
  318. # define this_cpu_write_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
  319. # endif
  320. # ifndef this_cpu_write_8
  321. # define this_cpu_write_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
  322. # endif
  323. # define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val))
  324. #endif
  325. #ifndef this_cpu_add
  326. # ifndef this_cpu_add_1
  327. # define this_cpu_add_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
  328. # endif
  329. # ifndef this_cpu_add_2
  330. # define this_cpu_add_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
  331. # endif
  332. # ifndef this_cpu_add_4
  333. # define this_cpu_add_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
  334. # endif
  335. # ifndef this_cpu_add_8
  336. # define this_cpu_add_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
  337. # endif
  338. # define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val))
  339. #endif
  340. #ifndef this_cpu_sub
  341. # define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(val))
  342. #endif
  343. #ifndef this_cpu_inc
  344. # define this_cpu_inc(pcp) this_cpu_add((pcp), 1)
  345. #endif
  346. #ifndef this_cpu_dec
  347. # define this_cpu_dec(pcp) this_cpu_sub((pcp), 1)
  348. #endif
  349. #ifndef this_cpu_and
  350. # ifndef this_cpu_and_1
  351. # define this_cpu_and_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
  352. # endif
  353. # ifndef this_cpu_and_2
  354. # define this_cpu_and_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
  355. # endif
  356. # ifndef this_cpu_and_4
  357. # define this_cpu_and_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
  358. # endif
  359. # ifndef this_cpu_and_8
  360. # define this_cpu_and_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
  361. # endif
  362. # define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val))
  363. #endif
  364. #ifndef this_cpu_or
  365. # ifndef this_cpu_or_1
  366. # define this_cpu_or_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
  367. # endif
  368. # ifndef this_cpu_or_2
  369. # define this_cpu_or_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
  370. # endif
  371. # ifndef this_cpu_or_4
  372. # define this_cpu_or_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
  373. # endif
  374. # ifndef this_cpu_or_8
  375. # define this_cpu_or_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
  376. # endif
  377. # define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
  378. #endif
  379. #ifndef this_cpu_xor
  380. # ifndef this_cpu_xor_1
  381. # define this_cpu_xor_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
  382. # endif
  383. # ifndef this_cpu_xor_2
  384. # define this_cpu_xor_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
  385. # endif
  386. # ifndef this_cpu_xor_4
  387. # define this_cpu_xor_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
  388. # endif
  389. # ifndef this_cpu_xor_8
  390. # define this_cpu_xor_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
  391. # endif
  392. # define this_cpu_xor(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
  393. #endif
  394. #define _this_cpu_generic_add_return(pcp, val) \
  395. ({ \
  396. typeof(pcp) ret__; \
  397. unsigned long flags; \
  398. raw_local_irq_save(flags); \
  399. __this_cpu_add(pcp, val); \
  400. ret__ = __this_cpu_read(pcp); \
  401. raw_local_irq_restore(flags); \
  402. ret__; \
  403. })
  404. #ifndef this_cpu_add_return
  405. # ifndef this_cpu_add_return_1
  406. # define this_cpu_add_return_1(pcp, val) _this_cpu_generic_add_return(pcp, val)
  407. # endif
  408. # ifndef this_cpu_add_return_2
  409. # define this_cpu_add_return_2(pcp, val) _this_cpu_generic_add_return(pcp, val)
  410. # endif
  411. # ifndef this_cpu_add_return_4
  412. # define this_cpu_add_return_4(pcp, val) _this_cpu_generic_add_return(pcp, val)
  413. # endif
  414. # ifndef this_cpu_add_return_8
  415. # define this_cpu_add_return_8(pcp, val) _this_cpu_generic_add_return(pcp, val)
  416. # endif
  417. # define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
  418. #endif
  419. #define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(val))
  420. #define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1)
  421. #define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1)
  422. #define _this_cpu_generic_xchg(pcp, nval) \
  423. ({ typeof(pcp) ret__; \
  424. unsigned long flags; \
  425. raw_local_irq_save(flags); \
  426. ret__ = __this_cpu_read(pcp); \
  427. __this_cpu_write(pcp, nval); \
  428. raw_local_irq_restore(flags); \
  429. ret__; \
  430. })
  431. #ifndef this_cpu_xchg
  432. # ifndef this_cpu_xchg_1
  433. # define this_cpu_xchg_1(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
  434. # endif
  435. # ifndef this_cpu_xchg_2
  436. # define this_cpu_xchg_2(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
  437. # endif
  438. # ifndef this_cpu_xchg_4
  439. # define this_cpu_xchg_4(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
  440. # endif
  441. # ifndef this_cpu_xchg_8
  442. # define this_cpu_xchg_8(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
  443. # endif
  444. # define this_cpu_xchg(pcp, nval) \
  445. __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval)
  446. #endif
  447. #define _this_cpu_generic_cmpxchg(pcp, oval, nval) \
  448. ({ \
  449. typeof(pcp) ret__; \
  450. unsigned long flags; \
  451. raw_local_irq_save(flags); \
  452. ret__ = __this_cpu_read(pcp); \
  453. if (ret__ == (oval)) \
  454. __this_cpu_write(pcp, nval); \
  455. raw_local_irq_restore(flags); \
  456. ret__; \
  457. })
  458. #ifndef this_cpu_cmpxchg
  459. # ifndef this_cpu_cmpxchg_1
  460. # define this_cpu_cmpxchg_1(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
  461. # endif
  462. # ifndef this_cpu_cmpxchg_2
  463. # define this_cpu_cmpxchg_2(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
  464. # endif
  465. # ifndef this_cpu_cmpxchg_4
  466. # define this_cpu_cmpxchg_4(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
  467. # endif
  468. # ifndef this_cpu_cmpxchg_8
  469. # define this_cpu_cmpxchg_8(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
  470. # endif
  471. # define this_cpu_cmpxchg(pcp, oval, nval) \
  472. __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
  473. #endif
  474. /*
  475. * cmpxchg_double replaces two adjacent scalars at once. The first
  476. * two parameters are per cpu variables which have to be of the same
  477. * size. A truth value is returned to indicate success or failure
  478. * (since a double register result is difficult to handle). There is
  479. * very limited hardware support for these operations, so only certain
  480. * sizes may work.
  481. */
  482. #define _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  483. ({ \
  484. int ret__; \
  485. unsigned long flags; \
  486. raw_local_irq_save(flags); \
  487. ret__ = __this_cpu_generic_cmpxchg_double(pcp1, pcp2, \
  488. oval1, oval2, nval1, nval2); \
  489. raw_local_irq_restore(flags); \
  490. ret__; \
  491. })
  492. #ifndef this_cpu_cmpxchg_double
  493. # ifndef this_cpu_cmpxchg_double_1
  494. # define this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  495. _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
  496. # endif
  497. # ifndef this_cpu_cmpxchg_double_2
  498. # define this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  499. _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
  500. # endif
  501. # ifndef this_cpu_cmpxchg_double_4
  502. # define this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  503. _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
  504. # endif
  505. # ifndef this_cpu_cmpxchg_double_8
  506. # define this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  507. _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
  508. # endif
  509. # define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  510. __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
  511. #endif
  512. /*
  513. * Generic percpu operations for context that are safe from preemption/interrupts.
  514. * Either we do not care about races or the caller has the
  515. * responsibility of handling preemption/interrupt issues. Arch code can still
  516. * override these instructions since the arch per cpu code may be more
  517. * efficient and may actually get race freeness for free (that is the
  518. * case for x86 for example).
  519. *
  520. * If there is no other protection through preempt disable and/or
  521. * disabling interupts then one of these RMW operations can show unexpected
  522. * behavior because the execution thread was rescheduled on another processor
  523. * or an interrupt occurred and the same percpu variable was modified from
  524. * the interrupt context.
  525. */
  526. #ifndef __this_cpu_read
  527. # ifndef __this_cpu_read_1
  528. # define __this_cpu_read_1(pcp) (*__this_cpu_ptr(&(pcp)))
  529. # endif
  530. # ifndef __this_cpu_read_2
  531. # define __this_cpu_read_2(pcp) (*__this_cpu_ptr(&(pcp)))
  532. # endif
  533. # ifndef __this_cpu_read_4
  534. # define __this_cpu_read_4(pcp) (*__this_cpu_ptr(&(pcp)))
  535. # endif
  536. # ifndef __this_cpu_read_8
  537. # define __this_cpu_read_8(pcp) (*__this_cpu_ptr(&(pcp)))
  538. # endif
  539. # define __this_cpu_read(pcp) __pcpu_size_call_return(__this_cpu_read_, (pcp))
  540. #endif
  541. #define __this_cpu_generic_to_op(pcp, val, op) \
  542. do { \
  543. *__this_cpu_ptr(&(pcp)) op val; \
  544. } while (0)
  545. #ifndef __this_cpu_write
  546. # ifndef __this_cpu_write_1
  547. # define __this_cpu_write_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
  548. # endif
  549. # ifndef __this_cpu_write_2
  550. # define __this_cpu_write_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
  551. # endif
  552. # ifndef __this_cpu_write_4
  553. # define __this_cpu_write_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
  554. # endif
  555. # ifndef __this_cpu_write_8
  556. # define __this_cpu_write_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
  557. # endif
  558. # define __this_cpu_write(pcp, val) __pcpu_size_call(__this_cpu_write_, (pcp), (val))
  559. #endif
  560. #ifndef __this_cpu_add
  561. # ifndef __this_cpu_add_1
  562. # define __this_cpu_add_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
  563. # endif
  564. # ifndef __this_cpu_add_2
  565. # define __this_cpu_add_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
  566. # endif
  567. # ifndef __this_cpu_add_4
  568. # define __this_cpu_add_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
  569. # endif
  570. # ifndef __this_cpu_add_8
  571. # define __this_cpu_add_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
  572. # endif
  573. # define __this_cpu_add(pcp, val) __pcpu_size_call(__this_cpu_add_, (pcp), (val))
  574. #endif
  575. #ifndef __this_cpu_sub
  576. # define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(val))
  577. #endif
  578. #ifndef __this_cpu_inc
  579. # define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1)
  580. #endif
  581. #ifndef __this_cpu_dec
  582. # define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1)
  583. #endif
  584. #ifndef __this_cpu_and
  585. # ifndef __this_cpu_and_1
  586. # define __this_cpu_and_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
  587. # endif
  588. # ifndef __this_cpu_and_2
  589. # define __this_cpu_and_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
  590. # endif
  591. # ifndef __this_cpu_and_4
  592. # define __this_cpu_and_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
  593. # endif
  594. # ifndef __this_cpu_and_8
  595. # define __this_cpu_and_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
  596. # endif
  597. # define __this_cpu_and(pcp, val) __pcpu_size_call(__this_cpu_and_, (pcp), (val))
  598. #endif
  599. #ifndef __this_cpu_or
  600. # ifndef __this_cpu_or_1
  601. # define __this_cpu_or_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
  602. # endif
  603. # ifndef __this_cpu_or_2
  604. # define __this_cpu_or_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
  605. # endif
  606. # ifndef __this_cpu_or_4
  607. # define __this_cpu_or_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
  608. # endif
  609. # ifndef __this_cpu_or_8
  610. # define __this_cpu_or_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
  611. # endif
  612. # define __this_cpu_or(pcp, val) __pcpu_size_call(__this_cpu_or_, (pcp), (val))
  613. #endif
  614. #ifndef __this_cpu_xor
  615. # ifndef __this_cpu_xor_1
  616. # define __this_cpu_xor_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
  617. # endif
  618. # ifndef __this_cpu_xor_2
  619. # define __this_cpu_xor_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
  620. # endif
  621. # ifndef __this_cpu_xor_4
  622. # define __this_cpu_xor_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
  623. # endif
  624. # ifndef __this_cpu_xor_8
  625. # define __this_cpu_xor_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
  626. # endif
  627. # define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
  628. #endif
  629. #define __this_cpu_generic_add_return(pcp, val) \
  630. ({ \
  631. __this_cpu_add(pcp, val); \
  632. __this_cpu_read(pcp); \
  633. })
  634. #ifndef __this_cpu_add_return
  635. # ifndef __this_cpu_add_return_1
  636. # define __this_cpu_add_return_1(pcp, val) __this_cpu_generic_add_return(pcp, val)
  637. # endif
  638. # ifndef __this_cpu_add_return_2
  639. # define __this_cpu_add_return_2(pcp, val) __this_cpu_generic_add_return(pcp, val)
  640. # endif
  641. # ifndef __this_cpu_add_return_4
  642. # define __this_cpu_add_return_4(pcp, val) __this_cpu_generic_add_return(pcp, val)
  643. # endif
  644. # ifndef __this_cpu_add_return_8
  645. # define __this_cpu_add_return_8(pcp, val) __this_cpu_generic_add_return(pcp, val)
  646. # endif
  647. # define __this_cpu_add_return(pcp, val) \
  648. __pcpu_size_call_return2(__this_cpu_add_return_, pcp, val)
  649. #endif
  650. #define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(val))
  651. #define __this_cpu_inc_return(pcp) __this_cpu_add_return(pcp, 1)
  652. #define __this_cpu_dec_return(pcp) __this_cpu_add_return(pcp, -1)
  653. #define __this_cpu_generic_xchg(pcp, nval) \
  654. ({ typeof(pcp) ret__; \
  655. ret__ = __this_cpu_read(pcp); \
  656. __this_cpu_write(pcp, nval); \
  657. ret__; \
  658. })
  659. #ifndef __this_cpu_xchg
  660. # ifndef __this_cpu_xchg_1
  661. # define __this_cpu_xchg_1(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
  662. # endif
  663. # ifndef __this_cpu_xchg_2
  664. # define __this_cpu_xchg_2(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
  665. # endif
  666. # ifndef __this_cpu_xchg_4
  667. # define __this_cpu_xchg_4(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
  668. # endif
  669. # ifndef __this_cpu_xchg_8
  670. # define __this_cpu_xchg_8(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
  671. # endif
  672. # define __this_cpu_xchg(pcp, nval) \
  673. __pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval)
  674. #endif
  675. #define __this_cpu_generic_cmpxchg(pcp, oval, nval) \
  676. ({ \
  677. typeof(pcp) ret__; \
  678. ret__ = __this_cpu_read(pcp); \
  679. if (ret__ == (oval)) \
  680. __this_cpu_write(pcp, nval); \
  681. ret__; \
  682. })
  683. #ifndef __this_cpu_cmpxchg
  684. # ifndef __this_cpu_cmpxchg_1
  685. # define __this_cpu_cmpxchg_1(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
  686. # endif
  687. # ifndef __this_cpu_cmpxchg_2
  688. # define __this_cpu_cmpxchg_2(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
  689. # endif
  690. # ifndef __this_cpu_cmpxchg_4
  691. # define __this_cpu_cmpxchg_4(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
  692. # endif
  693. # ifndef __this_cpu_cmpxchg_8
  694. # define __this_cpu_cmpxchg_8(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
  695. # endif
  696. # define __this_cpu_cmpxchg(pcp, oval, nval) \
  697. __pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval)
  698. #endif
  699. #define __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  700. ({ \
  701. int __ret = 0; \
  702. if (__this_cpu_read(pcp1) == (oval1) && \
  703. __this_cpu_read(pcp2) == (oval2)) { \
  704. __this_cpu_write(pcp1, (nval1)); \
  705. __this_cpu_write(pcp2, (nval2)); \
  706. __ret = 1; \
  707. } \
  708. (__ret); \
  709. })
  710. #ifndef __this_cpu_cmpxchg_double
  711. # ifndef __this_cpu_cmpxchg_double_1
  712. # define __this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  713. __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
  714. # endif
  715. # ifndef __this_cpu_cmpxchg_double_2
  716. # define __this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  717. __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
  718. # endif
  719. # ifndef __this_cpu_cmpxchg_double_4
  720. # define __this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  721. __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
  722. # endif
  723. # ifndef __this_cpu_cmpxchg_double_8
  724. # define __this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  725. __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
  726. # endif
  727. # define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
  728. __pcpu_double_call_return_bool(__this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
  729. #endif
  730. #endif /* __LINUX_PERCPU_H */