xref: /linux-6.15/include/linux/percpu.h (revision facb4edc)
1 #ifndef __LINUX_PERCPU_H
2 #define __LINUX_PERCPU_H
3 
4 #include <linux/preempt.h>
5 #include <linux/smp.h>
6 #include <linux/cpumask.h>
7 #include <linux/pfn.h>
8 #include <linux/init.h>
9 
10 #include <asm/percpu.h>
11 
12 /* enough to cover all DEFINE_PER_CPUs in modules */
13 #ifdef CONFIG_MODULES
14 #define PERCPU_MODULE_RESERVE		(8 << 10)
15 #else
16 #define PERCPU_MODULE_RESERVE		0
17 #endif
18 
19 #ifndef PERCPU_ENOUGH_ROOM
20 #define PERCPU_ENOUGH_ROOM						\
21 	(ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) +	\
22 	 PERCPU_MODULE_RESERVE)
23 #endif
24 
25 /*
26  * Must be an lvalue. Since @var must be a simple identifier,
27  * we force a syntax error here if it isn't.
28  */
29 #define get_cpu_var(var) (*({				\
30 	preempt_disable();				\
31 	&__get_cpu_var(var); }))
32 
33 /*
34  * The weird & is necessary because sparse considers (void)(var) to be
35  * a direct dereference of percpu variable (var).
36  */
37 #define put_cpu_var(var) do {				\
38 	(void)&(var);					\
39 	preempt_enable();				\
40 } while (0)
41 
42 #define get_cpu_ptr(var) ({				\
43 	preempt_disable();				\
44 	this_cpu_ptr(var); })
45 
46 #define put_cpu_ptr(var) do {				\
47 	(void)(var);					\
48 	preempt_enable();				\
49 } while (0)
50 
51 /* minimum unit size, also is the maximum supported allocation size */
52 #define PCPU_MIN_UNIT_SIZE		PFN_ALIGN(32 << 10)
53 
54 /*
55  * Percpu allocator can serve percpu allocations before slab is
56  * initialized which allows slab to depend on the percpu allocator.
57  * The following two parameters decide how much resource to
58  * preallocate for this.  Keep PERCPU_DYNAMIC_RESERVE equal to or
59  * larger than PERCPU_DYNAMIC_EARLY_SIZE.
60  */
61 #define PERCPU_DYNAMIC_EARLY_SLOTS	128
62 #define PERCPU_DYNAMIC_EARLY_SIZE	(12 << 10)
63 
64 /*
65  * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
66  * back on the first chunk for dynamic percpu allocation if arch is
67  * manually allocating and mapping it for faster access (as a part of
68  * large page mapping for example).
69  *
70  * The following values give between one and two pages of free space
71  * after typical minimal boot (2-way SMP, single disk and NIC) with
72  * both defconfig and a distro config on x86_64 and 32.  More
73  * intelligent way to determine this would be nice.
74  */
75 #if BITS_PER_LONG > 32
76 #define PERCPU_DYNAMIC_RESERVE		(20 << 10)
77 #else
78 #define PERCPU_DYNAMIC_RESERVE		(12 << 10)
79 #endif
80 
81 extern void *pcpu_base_addr;
82 extern const unsigned long *pcpu_unit_offsets;
83 
84 struct pcpu_group_info {
85 	int			nr_units;	/* aligned # of units */
86 	unsigned long		base_offset;	/* base address offset */
87 	unsigned int		*cpu_map;	/* unit->cpu map, empty
88 						 * entries contain NR_CPUS */
89 };
90 
91 struct pcpu_alloc_info {
92 	size_t			static_size;
93 	size_t			reserved_size;
94 	size_t			dyn_size;
95 	size_t			unit_size;
96 	size_t			atom_size;
97 	size_t			alloc_size;
98 	size_t			__ai_size;	/* internal, don't use */
99 	int			nr_groups;	/* 0 if grouping unnecessary */
100 	struct pcpu_group_info	groups[];
101 };
102 
103 enum pcpu_fc {
104 	PCPU_FC_AUTO,
105 	PCPU_FC_EMBED,
106 	PCPU_FC_PAGE,
107 
108 	PCPU_FC_NR,
109 };
110 extern const char *pcpu_fc_names[PCPU_FC_NR];
111 
112 extern enum pcpu_fc pcpu_chosen_fc;
113 
114 typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
115 				     size_t align);
116 typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
117 typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
118 typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
119 
120 extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
121 							     int nr_units);
122 extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
123 
124 extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
125 					 void *base_addr);
126 
127 #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
128 extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
129 				size_t atom_size,
130 				pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
131 				pcpu_fc_alloc_fn_t alloc_fn,
132 				pcpu_fc_free_fn_t free_fn);
133 #endif
134 
135 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
136 extern int __init pcpu_page_first_chunk(size_t reserved_size,
137 				pcpu_fc_alloc_fn_t alloc_fn,
138 				pcpu_fc_free_fn_t free_fn,
139 				pcpu_fc_populate_pte_fn_t populate_pte_fn);
140 #endif
141 
142 /*
143  * Use this to get to a cpu's version of the per-cpu object
144  * dynamically allocated. Non-atomic access to the current CPU's
145  * version should probably be combined with get_cpu()/put_cpu().
146  */
147 #ifdef CONFIG_SMP
148 #define per_cpu_ptr(ptr, cpu)	SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
149 #else
150 #define per_cpu_ptr(ptr, cpu)	({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })
151 #endif
152 
153 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
154 extern bool is_kernel_percpu_address(unsigned long addr);
155 
156 #if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
157 extern void __init setup_per_cpu_areas(void);
158 #endif
159 extern void __init percpu_init_late(void);
160 
161 extern void __percpu *__alloc_percpu(size_t size, size_t align);
162 extern void free_percpu(void __percpu *__pdata);
163 extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
164 
165 #define alloc_percpu(type)	\
166 	(typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
167 
168 /*
169  * Optional methods for optimized non-lvalue per-cpu variable access.
170  *
171  * @var can be a percpu variable or a field of it and its size should
172  * equal char, int or long.  percpu_read() evaluates to a lvalue and
173  * all others to void.
174  *
175  * These operations are guaranteed to be atomic w.r.t. preemption.
176  * The generic versions use plain get/put_cpu_var().  Archs are
177  * encouraged to implement single-instruction alternatives which don't
178  * require preemption protection.
179  */
180 #ifndef percpu_read
181 # define percpu_read(var)						\
182   ({									\
183 	typeof(var) *pr_ptr__ = &(var);					\
184 	typeof(var) pr_ret__;						\
185 	pr_ret__ = get_cpu_var(*pr_ptr__);				\
186 	put_cpu_var(*pr_ptr__);						\
187 	pr_ret__;							\
188   })
189 #endif
190 
191 #define __percpu_generic_to_op(var, val, op)				\
192 do {									\
193 	typeof(var) *pgto_ptr__ = &(var);				\
194 	get_cpu_var(*pgto_ptr__) op val;				\
195 	put_cpu_var(*pgto_ptr__);					\
196 } while (0)
197 
198 #ifndef percpu_write
199 # define percpu_write(var, val)		__percpu_generic_to_op(var, (val), =)
200 #endif
201 
202 #ifndef percpu_add
203 # define percpu_add(var, val)		__percpu_generic_to_op(var, (val), +=)
204 #endif
205 
206 #ifndef percpu_sub
207 # define percpu_sub(var, val)		__percpu_generic_to_op(var, (val), -=)
208 #endif
209 
210 #ifndef percpu_and
211 # define percpu_and(var, val)		__percpu_generic_to_op(var, (val), &=)
212 #endif
213 
214 #ifndef percpu_or
215 # define percpu_or(var, val)		__percpu_generic_to_op(var, (val), |=)
216 #endif
217 
218 #ifndef percpu_xor
219 # define percpu_xor(var, val)		__percpu_generic_to_op(var, (val), ^=)
220 #endif
221 
222 /*
223  * Branching function to split up a function into a set of functions that
224  * are called for different scalar sizes of the objects handled.
225  */
226 
227 extern void __bad_size_call_parameter(void);
228 
229 #define __pcpu_size_call_return(stem, variable)				\
230 ({	typeof(variable) pscr_ret__;					\
231 	__verify_pcpu_ptr(&(variable));					\
232 	switch(sizeof(variable)) {					\
233 	case 1: pscr_ret__ = stem##1(variable);break;			\
234 	case 2: pscr_ret__ = stem##2(variable);break;			\
235 	case 4: pscr_ret__ = stem##4(variable);break;			\
236 	case 8: pscr_ret__ = stem##8(variable);break;			\
237 	default:							\
238 		__bad_size_call_parameter();break;			\
239 	}								\
240 	pscr_ret__;							\
241 })
242 
243 #define __pcpu_size_call_return2(stem, variable, ...)			\
244 ({									\
245 	typeof(variable) pscr2_ret__;					\
246 	__verify_pcpu_ptr(&(variable));					\
247 	switch(sizeof(variable)) {					\
248 	case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break;	\
249 	case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break;	\
250 	case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break;	\
251 	case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break;	\
252 	default:							\
253 		__bad_size_call_parameter(); break;			\
254 	}								\
255 	pscr2_ret__;							\
256 })
257 
258 #define __pcpu_size_call(stem, variable, ...)				\
259 do {									\
260 	__verify_pcpu_ptr(&(variable));					\
261 	switch(sizeof(variable)) {					\
262 		case 1: stem##1(variable, __VA_ARGS__);break;		\
263 		case 2: stem##2(variable, __VA_ARGS__);break;		\
264 		case 4: stem##4(variable, __VA_ARGS__);break;		\
265 		case 8: stem##8(variable, __VA_ARGS__);break;		\
266 		default: 						\
267 			__bad_size_call_parameter();break;		\
268 	}								\
269 } while (0)
270 
271 /*
272  * Optimized manipulation for memory allocated through the per cpu
273  * allocator or for addresses of per cpu variables.
274  *
275  * These operation guarantee exclusivity of access for other operations
276  * on the *same* processor. The assumption is that per cpu data is only
277  * accessed by a single processor instance (the current one).
278  *
279  * The first group is used for accesses that must be done in a
280  * preemption safe way since we know that the context is not preempt
281  * safe. Interrupts may occur. If the interrupt modifies the variable
282  * too then RMW actions will not be reliable.
283  *
284  * The arch code can provide optimized functions in two ways:
285  *
286  * 1. Override the function completely. F.e. define this_cpu_add().
287  *    The arch must then ensure that the various scalar format passed
288  *    are handled correctly.
289  *
290  * 2. Provide functions for certain scalar sizes. F.e. provide
291  *    this_cpu_add_2() to provide per cpu atomic operations for 2 byte
292  *    sized RMW actions. If arch code does not provide operations for
293  *    a scalar size then the fallback in the generic code will be
294  *    used.
295  */
296 
297 #define _this_cpu_generic_read(pcp)					\
298 ({	typeof(pcp) ret__;						\
299 	preempt_disable();						\
300 	ret__ = *this_cpu_ptr(&(pcp));					\
301 	preempt_enable();						\
302 	ret__;								\
303 })
304 
305 #ifndef this_cpu_read
306 # ifndef this_cpu_read_1
307 #  define this_cpu_read_1(pcp)	_this_cpu_generic_read(pcp)
308 # endif
309 # ifndef this_cpu_read_2
310 #  define this_cpu_read_2(pcp)	_this_cpu_generic_read(pcp)
311 # endif
312 # ifndef this_cpu_read_4
313 #  define this_cpu_read_4(pcp)	_this_cpu_generic_read(pcp)
314 # endif
315 # ifndef this_cpu_read_8
316 #  define this_cpu_read_8(pcp)	_this_cpu_generic_read(pcp)
317 # endif
318 # define this_cpu_read(pcp)	__pcpu_size_call_return(this_cpu_read_, (pcp))
319 #endif
320 
321 #define _this_cpu_generic_to_op(pcp, val, op)				\
322 do {									\
323 	preempt_disable();						\
324 	*__this_cpu_ptr(&(pcp)) op val;					\
325 	preempt_enable();						\
326 } while (0)
327 
328 #ifndef this_cpu_write
329 # ifndef this_cpu_write_1
330 #  define this_cpu_write_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), =)
331 # endif
332 # ifndef this_cpu_write_2
333 #  define this_cpu_write_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), =)
334 # endif
335 # ifndef this_cpu_write_4
336 #  define this_cpu_write_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), =)
337 # endif
338 # ifndef this_cpu_write_8
339 #  define this_cpu_write_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), =)
340 # endif
341 # define this_cpu_write(pcp, val)	__pcpu_size_call(this_cpu_write_, (pcp), (val))
342 #endif
343 
344 #ifndef this_cpu_add
345 # ifndef this_cpu_add_1
346 #  define this_cpu_add_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), +=)
347 # endif
348 # ifndef this_cpu_add_2
349 #  define this_cpu_add_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), +=)
350 # endif
351 # ifndef this_cpu_add_4
352 #  define this_cpu_add_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), +=)
353 # endif
354 # ifndef this_cpu_add_8
355 #  define this_cpu_add_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), +=)
356 # endif
357 # define this_cpu_add(pcp, val)		__pcpu_size_call(this_cpu_add_, (pcp), (val))
358 #endif
359 
360 #ifndef this_cpu_sub
361 # define this_cpu_sub(pcp, val)		this_cpu_add((pcp), -(val))
362 #endif
363 
364 #ifndef this_cpu_inc
365 # define this_cpu_inc(pcp)		this_cpu_add((pcp), 1)
366 #endif
367 
368 #ifndef this_cpu_dec
369 # define this_cpu_dec(pcp)		this_cpu_sub((pcp), 1)
370 #endif
371 
372 #ifndef this_cpu_and
373 # ifndef this_cpu_and_1
374 #  define this_cpu_and_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), &=)
375 # endif
376 # ifndef this_cpu_and_2
377 #  define this_cpu_and_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), &=)
378 # endif
379 # ifndef this_cpu_and_4
380 #  define this_cpu_and_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), &=)
381 # endif
382 # ifndef this_cpu_and_8
383 #  define this_cpu_and_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), &=)
384 # endif
385 # define this_cpu_and(pcp, val)		__pcpu_size_call(this_cpu_and_, (pcp), (val))
386 #endif
387 
388 #ifndef this_cpu_or
389 # ifndef this_cpu_or_1
390 #  define this_cpu_or_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), |=)
391 # endif
392 # ifndef this_cpu_or_2
393 #  define this_cpu_or_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), |=)
394 # endif
395 # ifndef this_cpu_or_4
396 #  define this_cpu_or_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), |=)
397 # endif
398 # ifndef this_cpu_or_8
399 #  define this_cpu_or_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), |=)
400 # endif
401 # define this_cpu_or(pcp, val)		__pcpu_size_call(this_cpu_or_, (pcp), (val))
402 #endif
403 
404 #ifndef this_cpu_xor
405 # ifndef this_cpu_xor_1
406 #  define this_cpu_xor_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), ^=)
407 # endif
408 # ifndef this_cpu_xor_2
409 #  define this_cpu_xor_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), ^=)
410 # endif
411 # ifndef this_cpu_xor_4
412 #  define this_cpu_xor_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), ^=)
413 # endif
414 # ifndef this_cpu_xor_8
415 #  define this_cpu_xor_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), ^=)
416 # endif
417 # define this_cpu_xor(pcp, val)		__pcpu_size_call(this_cpu_or_, (pcp), (val))
418 #endif
419 
420 #define _this_cpu_generic_add_return(pcp, val)				\
421 ({									\
422 	typeof(pcp) ret__;						\
423 	preempt_disable();						\
424 	__this_cpu_add(pcp, val);					\
425 	ret__ = __this_cpu_read(pcp);					\
426 	preempt_enable();						\
427 	ret__;								\
428 })
429 
430 #ifndef this_cpu_add_return
431 # ifndef this_cpu_add_return_1
432 #  define this_cpu_add_return_1(pcp, val)	_this_cpu_generic_add_return(pcp, val)
433 # endif
434 # ifndef this_cpu_add_return_2
435 #  define this_cpu_add_return_2(pcp, val)	_this_cpu_generic_add_return(pcp, val)
436 # endif
437 # ifndef this_cpu_add_return_4
438 #  define this_cpu_add_return_4(pcp, val)	_this_cpu_generic_add_return(pcp, val)
439 # endif
440 # ifndef this_cpu_add_return_8
441 #  define this_cpu_add_return_8(pcp, val)	_this_cpu_generic_add_return(pcp, val)
442 # endif
443 # define this_cpu_add_return(pcp, val)	__pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
444 #endif
445 
446 #define this_cpu_sub_return(pcp, val)	this_cpu_add_return(pcp, -(val))
447 #define this_cpu_inc_return(pcp)	this_cpu_add_return(pcp, 1)
448 #define this_cpu_dec_return(pcp)	this_cpu_add_return(pcp, -1)
449 
450 #define _this_cpu_generic_xchg(pcp, nval)				\
451 ({	typeof(pcp) ret__;						\
452 	preempt_disable();						\
453 	ret__ = __this_cpu_read(pcp);					\
454 	__this_cpu_write(pcp, nval);					\
455 	preempt_enable();						\
456 	ret__;								\
457 })
458 
459 #ifndef this_cpu_xchg
460 # ifndef this_cpu_xchg_1
461 #  define this_cpu_xchg_1(pcp, nval)	_this_cpu_generic_xchg(pcp, nval)
462 # endif
463 # ifndef this_cpu_xchg_2
464 #  define this_cpu_xchg_2(pcp, nval)	_this_cpu_generic_xchg(pcp, nval)
465 # endif
466 # ifndef this_cpu_xchg_4
467 #  define this_cpu_xchg_4(pcp, nval)	_this_cpu_generic_xchg(pcp, nval)
468 # endif
469 # ifndef this_cpu_xchg_8
470 #  define this_cpu_xchg_8(pcp, nval)	_this_cpu_generic_xchg(pcp, nval)
471 # endif
472 # define this_cpu_xchg(pcp, nval)	\
473 	__pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval)
474 #endif
475 
476 #define _this_cpu_generic_cmpxchg(pcp, oval, nval)			\
477 ({	typeof(pcp) ret__;						\
478 	preempt_disable();						\
479 	ret__ = __this_cpu_read(pcp);					\
480 	if (ret__ == (oval))						\
481 		__this_cpu_write(pcp, nval);				\
482 	preempt_enable();						\
483 	ret__;								\
484 })
485 
486 #ifndef this_cpu_cmpxchg
487 # ifndef this_cpu_cmpxchg_1
488 #  define this_cpu_cmpxchg_1(pcp, oval, nval)	_this_cpu_generic_cmpxchg(pcp, oval, nval)
489 # endif
490 # ifndef this_cpu_cmpxchg_2
491 #  define this_cpu_cmpxchg_2(pcp, oval, nval)	_this_cpu_generic_cmpxchg(pcp, oval, nval)
492 # endif
493 # ifndef this_cpu_cmpxchg_4
494 #  define this_cpu_cmpxchg_4(pcp, oval, nval)	_this_cpu_generic_cmpxchg(pcp, oval, nval)
495 # endif
496 # ifndef this_cpu_cmpxchg_8
497 #  define this_cpu_cmpxchg_8(pcp, oval, nval)	_this_cpu_generic_cmpxchg(pcp, oval, nval)
498 # endif
499 # define this_cpu_cmpxchg(pcp, oval, nval)	\
500 	__pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
501 #endif
502 
503 /*
504  * Generic percpu operations that do not require preemption handling.
505  * Either we do not care about races or the caller has the
506  * responsibility of handling preemptions issues. Arch code can still
507  * override these instructions since the arch per cpu code may be more
508  * efficient and may actually get race freeness for free (that is the
509  * case for x86 for example).
510  *
511  * If there is no other protection through preempt disable and/or
512  * disabling interupts then one of these RMW operations can show unexpected
513  * behavior because the execution thread was rescheduled on another processor
514  * or an interrupt occurred and the same percpu variable was modified from
515  * the interrupt context.
516  */
517 #ifndef __this_cpu_read
518 # ifndef __this_cpu_read_1
519 #  define __this_cpu_read_1(pcp)	(*__this_cpu_ptr(&(pcp)))
520 # endif
521 # ifndef __this_cpu_read_2
522 #  define __this_cpu_read_2(pcp)	(*__this_cpu_ptr(&(pcp)))
523 # endif
524 # ifndef __this_cpu_read_4
525 #  define __this_cpu_read_4(pcp)	(*__this_cpu_ptr(&(pcp)))
526 # endif
527 # ifndef __this_cpu_read_8
528 #  define __this_cpu_read_8(pcp)	(*__this_cpu_ptr(&(pcp)))
529 # endif
530 # define __this_cpu_read(pcp)	__pcpu_size_call_return(__this_cpu_read_, (pcp))
531 #endif
532 
533 #define __this_cpu_generic_to_op(pcp, val, op)				\
534 do {									\
535 	*__this_cpu_ptr(&(pcp)) op val;					\
536 } while (0)
537 
538 #ifndef __this_cpu_write
539 # ifndef __this_cpu_write_1
540 #  define __this_cpu_write_1(pcp, val)	__this_cpu_generic_to_op((pcp), (val), =)
541 # endif
542 # ifndef __this_cpu_write_2
543 #  define __this_cpu_write_2(pcp, val)	__this_cpu_generic_to_op((pcp), (val), =)
544 # endif
545 # ifndef __this_cpu_write_4
546 #  define __this_cpu_write_4(pcp, val)	__this_cpu_generic_to_op((pcp), (val), =)
547 # endif
548 # ifndef __this_cpu_write_8
549 #  define __this_cpu_write_8(pcp, val)	__this_cpu_generic_to_op((pcp), (val), =)
550 # endif
551 # define __this_cpu_write(pcp, val)	__pcpu_size_call(__this_cpu_write_, (pcp), (val))
552 #endif
553 
554 #ifndef __this_cpu_add
555 # ifndef __this_cpu_add_1
556 #  define __this_cpu_add_1(pcp, val)	__this_cpu_generic_to_op((pcp), (val), +=)
557 # endif
558 # ifndef __this_cpu_add_2
559 #  define __this_cpu_add_2(pcp, val)	__this_cpu_generic_to_op((pcp), (val), +=)
560 # endif
561 # ifndef __this_cpu_add_4
562 #  define __this_cpu_add_4(pcp, val)	__this_cpu_generic_to_op((pcp), (val), +=)
563 # endif
564 # ifndef __this_cpu_add_8
565 #  define __this_cpu_add_8(pcp, val)	__this_cpu_generic_to_op((pcp), (val), +=)
566 # endif
567 # define __this_cpu_add(pcp, val)	__pcpu_size_call(__this_cpu_add_, (pcp), (val))
568 #endif
569 
570 #ifndef __this_cpu_sub
571 # define __this_cpu_sub(pcp, val)	__this_cpu_add((pcp), -(val))
572 #endif
573 
574 #ifndef __this_cpu_inc
575 # define __this_cpu_inc(pcp)		__this_cpu_add((pcp), 1)
576 #endif
577 
578 #ifndef __this_cpu_dec
579 # define __this_cpu_dec(pcp)		__this_cpu_sub((pcp), 1)
580 #endif
581 
582 #ifndef __this_cpu_and
583 # ifndef __this_cpu_and_1
584 #  define __this_cpu_and_1(pcp, val)	__this_cpu_generic_to_op((pcp), (val), &=)
585 # endif
586 # ifndef __this_cpu_and_2
587 #  define __this_cpu_and_2(pcp, val)	__this_cpu_generic_to_op((pcp), (val), &=)
588 # endif
589 # ifndef __this_cpu_and_4
590 #  define __this_cpu_and_4(pcp, val)	__this_cpu_generic_to_op((pcp), (val), &=)
591 # endif
592 # ifndef __this_cpu_and_8
593 #  define __this_cpu_and_8(pcp, val)	__this_cpu_generic_to_op((pcp), (val), &=)
594 # endif
595 # define __this_cpu_and(pcp, val)	__pcpu_size_call(__this_cpu_and_, (pcp), (val))
596 #endif
597 
598 #ifndef __this_cpu_or
599 # ifndef __this_cpu_or_1
600 #  define __this_cpu_or_1(pcp, val)	__this_cpu_generic_to_op((pcp), (val), |=)
601 # endif
602 # ifndef __this_cpu_or_2
603 #  define __this_cpu_or_2(pcp, val)	__this_cpu_generic_to_op((pcp), (val), |=)
604 # endif
605 # ifndef __this_cpu_or_4
606 #  define __this_cpu_or_4(pcp, val)	__this_cpu_generic_to_op((pcp), (val), |=)
607 # endif
608 # ifndef __this_cpu_or_8
609 #  define __this_cpu_or_8(pcp, val)	__this_cpu_generic_to_op((pcp), (val), |=)
610 # endif
611 # define __this_cpu_or(pcp, val)	__pcpu_size_call(__this_cpu_or_, (pcp), (val))
612 #endif
613 
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 
630 #define __this_cpu_generic_add_return(pcp, val)				\
631 ({									\
632 	__this_cpu_add(pcp, val);					\
633 	__this_cpu_read(pcp);						\
634 })
635 
636 #ifndef __this_cpu_add_return
637 # ifndef __this_cpu_add_return_1
638 #  define __this_cpu_add_return_1(pcp, val)	__this_cpu_generic_add_return(pcp, val)
639 # endif
640 # ifndef __this_cpu_add_return_2
641 #  define __this_cpu_add_return_2(pcp, val)	__this_cpu_generic_add_return(pcp, val)
642 # endif
643 # ifndef __this_cpu_add_return_4
644 #  define __this_cpu_add_return_4(pcp, val)	__this_cpu_generic_add_return(pcp, val)
645 # endif
646 # ifndef __this_cpu_add_return_8
647 #  define __this_cpu_add_return_8(pcp, val)	__this_cpu_generic_add_return(pcp, val)
648 # endif
649 # define __this_cpu_add_return(pcp, val)	__pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
650 #endif
651 
652 #define __this_cpu_sub_return(pcp, val)	this_cpu_add_return(pcp, -(val))
653 #define __this_cpu_inc_return(pcp)	this_cpu_add_return(pcp, 1)
654 #define __this_cpu_dec_return(pcp)	this_cpu_add_return(pcp, -1)
655 
656 #define __this_cpu_generic_xchg(pcp, nval)				\
657 ({	typeof(pcp) ret__;						\
658 	ret__ = __this_cpu_read(pcp);					\
659 	__this_cpu_write(pcp, nval);					\
660 	ret__;								\
661 })
662 
663 #ifndef __this_cpu_xchg
664 # ifndef __this_cpu_xchg_1
665 #  define __this_cpu_xchg_1(pcp, nval)	__this_cpu_generic_xchg(pcp, nval)
666 # endif
667 # ifndef __this_cpu_xchg_2
668 #  define __this_cpu_xchg_2(pcp, nval)	__this_cpu_generic_xchg(pcp, nval)
669 # endif
670 # ifndef __this_cpu_xchg_4
671 #  define __this_cpu_xchg_4(pcp, nval)	__this_cpu_generic_xchg(pcp, nval)
672 # endif
673 # ifndef __this_cpu_xchg_8
674 #  define __this_cpu_xchg_8(pcp, nval)	__this_cpu_generic_xchg(pcp, nval)
675 # endif
676 # define __this_cpu_xchg(pcp, nval)	\
677 	__pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval)
678 #endif
679 
680 #define __this_cpu_generic_cmpxchg(pcp, oval, nval)			\
681 ({									\
682 	typeof(pcp) ret__;						\
683 	ret__ = __this_cpu_read(pcp);					\
684 	if (ret__ == (oval))						\
685 		__this_cpu_write(pcp, nval);				\
686 	ret__;								\
687 })
688 
689 #ifndef __this_cpu_cmpxchg
690 # ifndef __this_cpu_cmpxchg_1
691 #  define __this_cpu_cmpxchg_1(pcp, oval, nval)	__this_cpu_generic_cmpxchg(pcp, oval, nval)
692 # endif
693 # ifndef __this_cpu_cmpxchg_2
694 #  define __this_cpu_cmpxchg_2(pcp, oval, nval)	__this_cpu_generic_cmpxchg(pcp, oval, nval)
695 # endif
696 # ifndef __this_cpu_cmpxchg_4
697 #  define __this_cpu_cmpxchg_4(pcp, oval, nval)	__this_cpu_generic_cmpxchg(pcp, oval, nval)
698 # endif
699 # ifndef __this_cpu_cmpxchg_8
700 #  define __this_cpu_cmpxchg_8(pcp, oval, nval)	__this_cpu_generic_cmpxchg(pcp, oval, nval)
701 # endif
702 # define __this_cpu_cmpxchg(pcp, oval, nval)	\
703 	__pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval)
704 #endif
705 
706 /*
707  * IRQ safe versions of the per cpu RMW operations. Note that these operations
708  * are *not* safe against modification of the same variable from another
709  * processors (which one gets when using regular atomic operations)
710  * They are guaranteed to be atomic vs. local interrupts and
711  * preemption only.
712  */
713 #define irqsafe_cpu_generic_to_op(pcp, val, op)				\
714 do {									\
715 	unsigned long flags;						\
716 	local_irq_save(flags);						\
717 	*__this_cpu_ptr(&(pcp)) op val;					\
718 	local_irq_restore(flags);					\
719 } while (0)
720 
721 #ifndef irqsafe_cpu_add
722 # ifndef irqsafe_cpu_add_1
723 #  define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
724 # endif
725 # ifndef irqsafe_cpu_add_2
726 #  define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
727 # endif
728 # ifndef irqsafe_cpu_add_4
729 #  define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
730 # endif
731 # ifndef irqsafe_cpu_add_8
732 #  define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
733 # endif
734 # define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val))
735 #endif
736 
737 #ifndef irqsafe_cpu_sub
738 # define irqsafe_cpu_sub(pcp, val)	irqsafe_cpu_add((pcp), -(val))
739 #endif
740 
741 #ifndef irqsafe_cpu_inc
742 # define irqsafe_cpu_inc(pcp)	irqsafe_cpu_add((pcp), 1)
743 #endif
744 
745 #ifndef irqsafe_cpu_dec
746 # define irqsafe_cpu_dec(pcp)	irqsafe_cpu_sub((pcp), 1)
747 #endif
748 
749 #ifndef irqsafe_cpu_and
750 # ifndef irqsafe_cpu_and_1
751 #  define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
752 # endif
753 # ifndef irqsafe_cpu_and_2
754 #  define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
755 # endif
756 # ifndef irqsafe_cpu_and_4
757 #  define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
758 # endif
759 # ifndef irqsafe_cpu_and_8
760 #  define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
761 # endif
762 # define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val))
763 #endif
764 
765 #ifndef irqsafe_cpu_or
766 # ifndef irqsafe_cpu_or_1
767 #  define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
768 # endif
769 # ifndef irqsafe_cpu_or_2
770 #  define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
771 # endif
772 # ifndef irqsafe_cpu_or_4
773 #  define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
774 # endif
775 # ifndef irqsafe_cpu_or_8
776 #  define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
777 # endif
778 # define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val))
779 #endif
780 
781 #ifndef irqsafe_cpu_xor
782 # ifndef irqsafe_cpu_xor_1
783 #  define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
784 # endif
785 # ifndef irqsafe_cpu_xor_2
786 #  define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
787 # endif
788 # ifndef irqsafe_cpu_xor_4
789 #  define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
790 # endif
791 # ifndef irqsafe_cpu_xor_8
792 #  define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
793 # endif
794 # define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val))
795 #endif
796 
797 #define irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)			\
798 ({									\
799 	typeof(pcp) ret__;						\
800 	unsigned long flags;						\
801 	local_irq_save(flags);						\
802 	ret__ = __this_cpu_read(pcp);					\
803 	if (ret__ == (oval))						\
804 		__this_cpu_write(pcp, nval);				\
805 	local_irq_restore(flags);					\
806 	ret__;								\
807 })
808 
809 #ifndef irqsafe_cpu_cmpxchg
810 # ifndef irqsafe_cpu_cmpxchg_1
811 #  define irqsafe_cpu_cmpxchg_1(pcp, oval, nval)	irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
812 # endif
813 # ifndef irqsafe_cpu_cmpxchg_2
814 #  define irqsafe_cpu_cmpxchg_2(pcp, oval, nval)	irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
815 # endif
816 # ifndef irqsafe_cpu_cmpxchg_4
817 #  define irqsafe_cpu_cmpxchg_4(pcp, oval, nval)	irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
818 # endif
819 # ifndef irqsafe_cpu_cmpxchg_8
820 #  define irqsafe_cpu_cmpxchg_8(pcp, oval, nval)	irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
821 # endif
822 # define irqsafe_cpu_cmpxchg(pcp, oval, nval)		\
823 	__pcpu_size_call_return2(irqsafe_cpu_cmpxchg_, (pcp), oval, nval)
824 #endif
825 
826 #endif /* __LINUX_PERCPU_H */
827