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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.
176  * The generic versions disable interrupts.  Archs are
177  * encouraged to implement single-instruction alternatives which don't
178  * require 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 /*
259  * Special handling for cmpxchg_double.  cmpxchg_double is passed two
260  * percpu variables.  The first has to be aligned to a double word
261  * boundary and the second has to follow directly thereafter.
262  * We enforce this on all architectures even if they don't support
263  * a double cmpxchg instruction, since it's a cheap requirement, and it
264  * avoids breaking the requirement for architectures with the instruction.
265  */
266 #define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...)		\
267 ({									\
268 	bool pdcrb_ret__;						\
269 	__verify_pcpu_ptr(&pcp1);					\
270 	BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2));			\
271 	VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1)));		\
272 	VM_BUG_ON((unsigned long)(&pcp2) !=				\
273 		  (unsigned long)(&pcp1) + sizeof(pcp1));		\
274 	switch(sizeof(pcp1)) {						\
275 	case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break;	\
276 	case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break;	\
277 	case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break;	\
278 	case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break;	\
279 	default:							\
280 		__bad_size_call_parameter(); break;			\
281 	}								\
282 	pdcrb_ret__;							\
283 })
284 
285 #define __pcpu_size_call(stem, variable, ...)				\
286 do {									\
287 	__verify_pcpu_ptr(&(variable));					\
288 	switch(sizeof(variable)) {					\
289 		case 1: stem##1(variable, __VA_ARGS__);break;		\
290 		case 2: stem##2(variable, __VA_ARGS__);break;		\
291 		case 4: stem##4(variable, __VA_ARGS__);break;		\
292 		case 8: stem##8(variable, __VA_ARGS__);break;		\
293 		default: 						\
294 			__bad_size_call_parameter();break;		\
295 	}								\
296 } while (0)
297 
298 /*
299  * Optimized manipulation for memory allocated through the per cpu
300  * allocator or for addresses of per cpu variables.
301  *
302  * These operation guarantee exclusivity of access for other operations
303  * on the *same* processor. The assumption is that per cpu data is only
304  * accessed by a single processor instance (the current one).
305  *
306  * The first group is used for accesses that must be done in a
307  * preemption safe way since we know that the context is not preempt
308  * safe. Interrupts may occur. If the interrupt modifies the variable
309  * too then RMW actions will not be reliable.
310  *
311  * The arch code can provide optimized functions in two ways:
312  *
313  * 1. Override the function completely. F.e. define this_cpu_add().
314  *    The arch must then ensure that the various scalar format passed
315  *    are handled correctly.
316  *
317  * 2. Provide functions for certain scalar sizes. F.e. provide
318  *    this_cpu_add_2() to provide per cpu atomic operations for 2 byte
319  *    sized RMW actions. If arch code does not provide operations for
320  *    a scalar size then the fallback in the generic code will be
321  *    used.
322  */
323 
324 #define _this_cpu_generic_read(pcp)					\
325 ({	typeof(pcp) ret__;						\
326 	preempt_disable();						\
327 	ret__ = *this_cpu_ptr(&(pcp));					\
328 	preempt_enable();						\
329 	ret__;								\
330 })
331 
332 #ifndef this_cpu_read
333 # ifndef this_cpu_read_1
334 #  define this_cpu_read_1(pcp)	_this_cpu_generic_read(pcp)
335 # endif
336 # ifndef this_cpu_read_2
337 #  define this_cpu_read_2(pcp)	_this_cpu_generic_read(pcp)
338 # endif
339 # ifndef this_cpu_read_4
340 #  define this_cpu_read_4(pcp)	_this_cpu_generic_read(pcp)
341 # endif
342 # ifndef this_cpu_read_8
343 #  define this_cpu_read_8(pcp)	_this_cpu_generic_read(pcp)
344 # endif
345 # define this_cpu_read(pcp)	__pcpu_size_call_return(this_cpu_read_, (pcp))
346 #endif
347 
348 #define _this_cpu_generic_to_op(pcp, val, op)				\
349 do {									\
350 	unsigned long flags;						\
351 	raw_local_irq_save(flags);					\
352 	*__this_cpu_ptr(&(pcp)) op val;					\
353 	raw_local_irq_restore(flags);					\
354 } while (0)
355 
356 #ifndef this_cpu_write
357 # ifndef this_cpu_write_1
358 #  define this_cpu_write_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), =)
359 # endif
360 # ifndef this_cpu_write_2
361 #  define this_cpu_write_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), =)
362 # endif
363 # ifndef this_cpu_write_4
364 #  define this_cpu_write_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), =)
365 # endif
366 # ifndef this_cpu_write_8
367 #  define this_cpu_write_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), =)
368 # endif
369 # define this_cpu_write(pcp, val)	__pcpu_size_call(this_cpu_write_, (pcp), (val))
370 #endif
371 
372 #ifndef this_cpu_add
373 # ifndef this_cpu_add_1
374 #  define this_cpu_add_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), +=)
375 # endif
376 # ifndef this_cpu_add_2
377 #  define this_cpu_add_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), +=)
378 # endif
379 # ifndef this_cpu_add_4
380 #  define this_cpu_add_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), +=)
381 # endif
382 # ifndef this_cpu_add_8
383 #  define this_cpu_add_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), +=)
384 # endif
385 # define this_cpu_add(pcp, val)		__pcpu_size_call(this_cpu_add_, (pcp), (val))
386 #endif
387 
388 #ifndef this_cpu_sub
389 # define this_cpu_sub(pcp, val)		this_cpu_add((pcp), -(val))
390 #endif
391 
392 #ifndef this_cpu_inc
393 # define this_cpu_inc(pcp)		this_cpu_add((pcp), 1)
394 #endif
395 
396 #ifndef this_cpu_dec
397 # define this_cpu_dec(pcp)		this_cpu_sub((pcp), 1)
398 #endif
399 
400 #ifndef this_cpu_and
401 # ifndef this_cpu_and_1
402 #  define this_cpu_and_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), &=)
403 # endif
404 # ifndef this_cpu_and_2
405 #  define this_cpu_and_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), &=)
406 # endif
407 # ifndef this_cpu_and_4
408 #  define this_cpu_and_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), &=)
409 # endif
410 # ifndef this_cpu_and_8
411 #  define this_cpu_and_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), &=)
412 # endif
413 # define this_cpu_and(pcp, val)		__pcpu_size_call(this_cpu_and_, (pcp), (val))
414 #endif
415 
416 #ifndef this_cpu_or
417 # ifndef this_cpu_or_1
418 #  define this_cpu_or_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), |=)
419 # endif
420 # ifndef this_cpu_or_2
421 #  define this_cpu_or_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), |=)
422 # endif
423 # ifndef this_cpu_or_4
424 #  define this_cpu_or_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), |=)
425 # endif
426 # ifndef this_cpu_or_8
427 #  define this_cpu_or_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), |=)
428 # endif
429 # define this_cpu_or(pcp, val)		__pcpu_size_call(this_cpu_or_, (pcp), (val))
430 #endif
431 
432 #ifndef this_cpu_xor
433 # ifndef this_cpu_xor_1
434 #  define this_cpu_xor_1(pcp, val)	_this_cpu_generic_to_op((pcp), (val), ^=)
435 # endif
436 # ifndef this_cpu_xor_2
437 #  define this_cpu_xor_2(pcp, val)	_this_cpu_generic_to_op((pcp), (val), ^=)
438 # endif
439 # ifndef this_cpu_xor_4
440 #  define this_cpu_xor_4(pcp, val)	_this_cpu_generic_to_op((pcp), (val), ^=)
441 # endif
442 # ifndef this_cpu_xor_8
443 #  define this_cpu_xor_8(pcp, val)	_this_cpu_generic_to_op((pcp), (val), ^=)
444 # endif
445 # define this_cpu_xor(pcp, val)		__pcpu_size_call(this_cpu_or_, (pcp), (val))
446 #endif
447 
448 #define _this_cpu_generic_add_return(pcp, val)				\
449 ({									\
450 	typeof(pcp) ret__;						\
451 	unsigned long flags;						\
452 	raw_local_irq_save(flags);					\
453 	__this_cpu_add(pcp, val);					\
454 	ret__ = __this_cpu_read(pcp);					\
455 	raw_local_irq_restore(flags);					\
456 	ret__;								\
457 })
458 
459 #ifndef this_cpu_add_return
460 # ifndef this_cpu_add_return_1
461 #  define this_cpu_add_return_1(pcp, val)	_this_cpu_generic_add_return(pcp, val)
462 # endif
463 # ifndef this_cpu_add_return_2
464 #  define this_cpu_add_return_2(pcp, val)	_this_cpu_generic_add_return(pcp, val)
465 # endif
466 # ifndef this_cpu_add_return_4
467 #  define this_cpu_add_return_4(pcp, val)	_this_cpu_generic_add_return(pcp, val)
468 # endif
469 # ifndef this_cpu_add_return_8
470 #  define this_cpu_add_return_8(pcp, val)	_this_cpu_generic_add_return(pcp, val)
471 # endif
472 # define this_cpu_add_return(pcp, val)	__pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
473 #endif
474 
475 #define this_cpu_sub_return(pcp, val)	this_cpu_add_return(pcp, -(val))
476 #define this_cpu_inc_return(pcp)	this_cpu_add_return(pcp, 1)
477 #define this_cpu_dec_return(pcp)	this_cpu_add_return(pcp, -1)
478 
479 #define _this_cpu_generic_xchg(pcp, nval)				\
480 ({	typeof(pcp) ret__;						\
481 	unsigned long flags;						\
482 	raw_local_irq_save(flags);					\
483 	ret__ = __this_cpu_read(pcp);					\
484 	__this_cpu_write(pcp, nval);					\
485 	raw_local_irq_restore(flags);					\
486 	ret__;								\
487 })
488 
489 #ifndef this_cpu_xchg
490 # ifndef this_cpu_xchg_1
491 #  define this_cpu_xchg_1(pcp, nval)	_this_cpu_generic_xchg(pcp, nval)
492 # endif
493 # ifndef this_cpu_xchg_2
494 #  define this_cpu_xchg_2(pcp, nval)	_this_cpu_generic_xchg(pcp, nval)
495 # endif
496 # ifndef this_cpu_xchg_4
497 #  define this_cpu_xchg_4(pcp, nval)	_this_cpu_generic_xchg(pcp, nval)
498 # endif
499 # ifndef this_cpu_xchg_8
500 #  define this_cpu_xchg_8(pcp, nval)	_this_cpu_generic_xchg(pcp, nval)
501 # endif
502 # define this_cpu_xchg(pcp, nval)	\
503 	__pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval)
504 #endif
505 
506 #define _this_cpu_generic_cmpxchg(pcp, oval, nval)			\
507 ({									\
508 	typeof(pcp) ret__;						\
509 	unsigned long flags;						\
510 	raw_local_irq_save(flags);					\
511 	ret__ = __this_cpu_read(pcp);					\
512 	if (ret__ == (oval))						\
513 		__this_cpu_write(pcp, nval);				\
514 	raw_local_irq_restore(flags);					\
515 	ret__;								\
516 })
517 
518 #ifndef this_cpu_cmpxchg
519 # ifndef this_cpu_cmpxchg_1
520 #  define this_cpu_cmpxchg_1(pcp, oval, nval)	_this_cpu_generic_cmpxchg(pcp, oval, nval)
521 # endif
522 # ifndef this_cpu_cmpxchg_2
523 #  define this_cpu_cmpxchg_2(pcp, oval, nval)	_this_cpu_generic_cmpxchg(pcp, oval, nval)
524 # endif
525 # ifndef this_cpu_cmpxchg_4
526 #  define this_cpu_cmpxchg_4(pcp, oval, nval)	_this_cpu_generic_cmpxchg(pcp, oval, nval)
527 # endif
528 # ifndef this_cpu_cmpxchg_8
529 #  define this_cpu_cmpxchg_8(pcp, oval, nval)	_this_cpu_generic_cmpxchg(pcp, oval, nval)
530 # endif
531 # define this_cpu_cmpxchg(pcp, oval, nval)	\
532 	__pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
533 #endif
534 
535 /*
536  * cmpxchg_double replaces two adjacent scalars at once.  The first
537  * two parameters are per cpu variables which have to be of the same
538  * size.  A truth value is returned to indicate success or failure
539  * (since a double register result is difficult to handle).  There is
540  * very limited hardware support for these operations, so only certain
541  * sizes may work.
542  */
543 #define _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
544 ({									\
545 	int ret__;							\
546 	unsigned long flags;						\
547 	raw_local_irq_save(flags);					\
548 	ret__ = __this_cpu_generic_cmpxchg_double(pcp1, pcp2,		\
549 			oval1, oval2, nval1, nval2);			\
550 	raw_local_irq_restore(flags);					\
551 	ret__;								\
552 })
553 
554 #ifndef this_cpu_cmpxchg_double
555 # ifndef this_cpu_cmpxchg_double_1
556 #  define this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
557 	_this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
558 # endif
559 # ifndef this_cpu_cmpxchg_double_2
560 #  define this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
561 	_this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
562 # endif
563 # ifndef this_cpu_cmpxchg_double_4
564 #  define this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
565 	_this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
566 # endif
567 # ifndef this_cpu_cmpxchg_double_8
568 #  define this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
569 	_this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
570 # endif
571 # define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
572 	__pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
573 #endif
574 
575 /*
576  * Generic percpu operations for context that are safe from preemption/interrupts.
577  * Either we do not care about races or the caller has the
578  * responsibility of handling preemption/interrupt issues. Arch code can still
579  * override these instructions since the arch per cpu code may be more
580  * efficient and may actually get race freeness for free (that is the
581  * case for x86 for example).
582  *
583  * If there is no other protection through preempt disable and/or
584  * disabling interupts then one of these RMW operations can show unexpected
585  * behavior because the execution thread was rescheduled on another processor
586  * or an interrupt occurred and the same percpu variable was modified from
587  * the interrupt context.
588  */
589 #ifndef __this_cpu_read
590 # ifndef __this_cpu_read_1
591 #  define __this_cpu_read_1(pcp)	(*__this_cpu_ptr(&(pcp)))
592 # endif
593 # ifndef __this_cpu_read_2
594 #  define __this_cpu_read_2(pcp)	(*__this_cpu_ptr(&(pcp)))
595 # endif
596 # ifndef __this_cpu_read_4
597 #  define __this_cpu_read_4(pcp)	(*__this_cpu_ptr(&(pcp)))
598 # endif
599 # ifndef __this_cpu_read_8
600 #  define __this_cpu_read_8(pcp)	(*__this_cpu_ptr(&(pcp)))
601 # endif
602 # define __this_cpu_read(pcp)	__pcpu_size_call_return(__this_cpu_read_, (pcp))
603 #endif
604 
605 #define __this_cpu_generic_to_op(pcp, val, op)				\
606 do {									\
607 	*__this_cpu_ptr(&(pcp)) op val;					\
608 } while (0)
609 
610 #ifndef __this_cpu_write
611 # ifndef __this_cpu_write_1
612 #  define __this_cpu_write_1(pcp, val)	__this_cpu_generic_to_op((pcp), (val), =)
613 # endif
614 # ifndef __this_cpu_write_2
615 #  define __this_cpu_write_2(pcp, val)	__this_cpu_generic_to_op((pcp), (val), =)
616 # endif
617 # ifndef __this_cpu_write_4
618 #  define __this_cpu_write_4(pcp, val)	__this_cpu_generic_to_op((pcp), (val), =)
619 # endif
620 # ifndef __this_cpu_write_8
621 #  define __this_cpu_write_8(pcp, val)	__this_cpu_generic_to_op((pcp), (val), =)
622 # endif
623 # define __this_cpu_write(pcp, val)	__pcpu_size_call(__this_cpu_write_, (pcp), (val))
624 #endif
625 
626 #ifndef __this_cpu_add
627 # ifndef __this_cpu_add_1
628 #  define __this_cpu_add_1(pcp, val)	__this_cpu_generic_to_op((pcp), (val), +=)
629 # endif
630 # ifndef __this_cpu_add_2
631 #  define __this_cpu_add_2(pcp, val)	__this_cpu_generic_to_op((pcp), (val), +=)
632 # endif
633 # ifndef __this_cpu_add_4
634 #  define __this_cpu_add_4(pcp, val)	__this_cpu_generic_to_op((pcp), (val), +=)
635 # endif
636 # ifndef __this_cpu_add_8
637 #  define __this_cpu_add_8(pcp, val)	__this_cpu_generic_to_op((pcp), (val), +=)
638 # endif
639 # define __this_cpu_add(pcp, val)	__pcpu_size_call(__this_cpu_add_, (pcp), (val))
640 #endif
641 
642 #ifndef __this_cpu_sub
643 # define __this_cpu_sub(pcp, val)	__this_cpu_add((pcp), -(val))
644 #endif
645 
646 #ifndef __this_cpu_inc
647 # define __this_cpu_inc(pcp)		__this_cpu_add((pcp), 1)
648 #endif
649 
650 #ifndef __this_cpu_dec
651 # define __this_cpu_dec(pcp)		__this_cpu_sub((pcp), 1)
652 #endif
653 
654 #ifndef __this_cpu_and
655 # ifndef __this_cpu_and_1
656 #  define __this_cpu_and_1(pcp, val)	__this_cpu_generic_to_op((pcp), (val), &=)
657 # endif
658 # ifndef __this_cpu_and_2
659 #  define __this_cpu_and_2(pcp, val)	__this_cpu_generic_to_op((pcp), (val), &=)
660 # endif
661 # ifndef __this_cpu_and_4
662 #  define __this_cpu_and_4(pcp, val)	__this_cpu_generic_to_op((pcp), (val), &=)
663 # endif
664 # ifndef __this_cpu_and_8
665 #  define __this_cpu_and_8(pcp, val)	__this_cpu_generic_to_op((pcp), (val), &=)
666 # endif
667 # define __this_cpu_and(pcp, val)	__pcpu_size_call(__this_cpu_and_, (pcp), (val))
668 #endif
669 
670 #ifndef __this_cpu_or
671 # ifndef __this_cpu_or_1
672 #  define __this_cpu_or_1(pcp, val)	__this_cpu_generic_to_op((pcp), (val), |=)
673 # endif
674 # ifndef __this_cpu_or_2
675 #  define __this_cpu_or_2(pcp, val)	__this_cpu_generic_to_op((pcp), (val), |=)
676 # endif
677 # ifndef __this_cpu_or_4
678 #  define __this_cpu_or_4(pcp, val)	__this_cpu_generic_to_op((pcp), (val), |=)
679 # endif
680 # ifndef __this_cpu_or_8
681 #  define __this_cpu_or_8(pcp, val)	__this_cpu_generic_to_op((pcp), (val), |=)
682 # endif
683 # define __this_cpu_or(pcp, val)	__pcpu_size_call(__this_cpu_or_, (pcp), (val))
684 #endif
685 
686 #ifndef __this_cpu_xor
687 # ifndef __this_cpu_xor_1
688 #  define __this_cpu_xor_1(pcp, val)	__this_cpu_generic_to_op((pcp), (val), ^=)
689 # endif
690 # ifndef __this_cpu_xor_2
691 #  define __this_cpu_xor_2(pcp, val)	__this_cpu_generic_to_op((pcp), (val), ^=)
692 # endif
693 # ifndef __this_cpu_xor_4
694 #  define __this_cpu_xor_4(pcp, val)	__this_cpu_generic_to_op((pcp), (val), ^=)
695 # endif
696 # ifndef __this_cpu_xor_8
697 #  define __this_cpu_xor_8(pcp, val)	__this_cpu_generic_to_op((pcp), (val), ^=)
698 # endif
699 # define __this_cpu_xor(pcp, val)	__pcpu_size_call(__this_cpu_xor_, (pcp), (val))
700 #endif
701 
702 #define __this_cpu_generic_add_return(pcp, val)				\
703 ({									\
704 	__this_cpu_add(pcp, val);					\
705 	__this_cpu_read(pcp);						\
706 })
707 
708 #ifndef __this_cpu_add_return
709 # ifndef __this_cpu_add_return_1
710 #  define __this_cpu_add_return_1(pcp, val)	__this_cpu_generic_add_return(pcp, val)
711 # endif
712 # ifndef __this_cpu_add_return_2
713 #  define __this_cpu_add_return_2(pcp, val)	__this_cpu_generic_add_return(pcp, val)
714 # endif
715 # ifndef __this_cpu_add_return_4
716 #  define __this_cpu_add_return_4(pcp, val)	__this_cpu_generic_add_return(pcp, val)
717 # endif
718 # ifndef __this_cpu_add_return_8
719 #  define __this_cpu_add_return_8(pcp, val)	__this_cpu_generic_add_return(pcp, val)
720 # endif
721 # define __this_cpu_add_return(pcp, val)	\
722 	__pcpu_size_call_return2(__this_cpu_add_return_, pcp, val)
723 #endif
724 
725 #define __this_cpu_sub_return(pcp, val)	__this_cpu_add_return(pcp, -(val))
726 #define __this_cpu_inc_return(pcp)	__this_cpu_add_return(pcp, 1)
727 #define __this_cpu_dec_return(pcp)	__this_cpu_add_return(pcp, -1)
728 
729 #define __this_cpu_generic_xchg(pcp, nval)				\
730 ({	typeof(pcp) ret__;						\
731 	ret__ = __this_cpu_read(pcp);					\
732 	__this_cpu_write(pcp, nval);					\
733 	ret__;								\
734 })
735 
736 #ifndef __this_cpu_xchg
737 # ifndef __this_cpu_xchg_1
738 #  define __this_cpu_xchg_1(pcp, nval)	__this_cpu_generic_xchg(pcp, nval)
739 # endif
740 # ifndef __this_cpu_xchg_2
741 #  define __this_cpu_xchg_2(pcp, nval)	__this_cpu_generic_xchg(pcp, nval)
742 # endif
743 # ifndef __this_cpu_xchg_4
744 #  define __this_cpu_xchg_4(pcp, nval)	__this_cpu_generic_xchg(pcp, nval)
745 # endif
746 # ifndef __this_cpu_xchg_8
747 #  define __this_cpu_xchg_8(pcp, nval)	__this_cpu_generic_xchg(pcp, nval)
748 # endif
749 # define __this_cpu_xchg(pcp, nval)	\
750 	__pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval)
751 #endif
752 
753 #define __this_cpu_generic_cmpxchg(pcp, oval, nval)			\
754 ({									\
755 	typeof(pcp) ret__;						\
756 	ret__ = __this_cpu_read(pcp);					\
757 	if (ret__ == (oval))						\
758 		__this_cpu_write(pcp, nval);				\
759 	ret__;								\
760 })
761 
762 #ifndef __this_cpu_cmpxchg
763 # ifndef __this_cpu_cmpxchg_1
764 #  define __this_cpu_cmpxchg_1(pcp, oval, nval)	__this_cpu_generic_cmpxchg(pcp, oval, nval)
765 # endif
766 # ifndef __this_cpu_cmpxchg_2
767 #  define __this_cpu_cmpxchg_2(pcp, oval, nval)	__this_cpu_generic_cmpxchg(pcp, oval, nval)
768 # endif
769 # ifndef __this_cpu_cmpxchg_4
770 #  define __this_cpu_cmpxchg_4(pcp, oval, nval)	__this_cpu_generic_cmpxchg(pcp, oval, nval)
771 # endif
772 # ifndef __this_cpu_cmpxchg_8
773 #  define __this_cpu_cmpxchg_8(pcp, oval, nval)	__this_cpu_generic_cmpxchg(pcp, oval, nval)
774 # endif
775 # define __this_cpu_cmpxchg(pcp, oval, nval)	\
776 	__pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval)
777 #endif
778 
779 #define __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
780 ({									\
781 	int __ret = 0;							\
782 	if (__this_cpu_read(pcp1) == (oval1) &&				\
783 			 __this_cpu_read(pcp2)  == (oval2)) {		\
784 		__this_cpu_write(pcp1, (nval1));			\
785 		__this_cpu_write(pcp2, (nval2));			\
786 		__ret = 1;						\
787 	}								\
788 	(__ret);							\
789 })
790 
791 #ifndef __this_cpu_cmpxchg_double
792 # ifndef __this_cpu_cmpxchg_double_1
793 #  define __this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
794 	__this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
795 # endif
796 # ifndef __this_cpu_cmpxchg_double_2
797 #  define __this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
798 	__this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
799 # endif
800 # ifndef __this_cpu_cmpxchg_double_4
801 #  define __this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
802 	__this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
803 # endif
804 # ifndef __this_cpu_cmpxchg_double_8
805 #  define __this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
806 	__this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
807 # endif
808 # define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)	\
809 	__pcpu_double_call_return_bool(__this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
810 #endif
811 
812 #endif /* __LINUX_PERCPU_H */
813