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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef __LINUX_PERCPU_H
2#define __LINUX_PERCPU_H
Martin Peschke7ff6f082006-09-25 23:31:21 -07003
Robert P. J. Day0a3021f2007-07-15 23:39:57 -07004#include <linux/preempt.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07005#include <linux/slab.h> /* For kmalloc() */
6#include <linux/smp.h>
Martin Peschke7ff6f082006-09-25 23:31:21 -07007#include <linux/cpumask.h>
Tejun Heo6a242902009-03-06 14:33:58 +09008#include <linux/pfn.h>
Martin Peschke7ff6f082006-09-25 23:31:21 -07009
Linus Torvalds1da177e2005-04-16 15:20:36 -070010#include <asm/percpu.h>
11
Tejun Heo6a242902009-03-06 14:33:58 +090012/* enough to cover all DEFINE_PER_CPUs in modules */
Jeremy Fitzhardingeb00742d2007-05-02 19:27:11 +020013#ifdef CONFIG_MODULES
Tejun Heo6a242902009-03-06 14:33:58 +090014#define PERCPU_MODULE_RESERVE (8 << 10)
Jeremy Fitzhardingeb00742d2007-05-02 19:27:11 +020015#else
Tejun Heo6a242902009-03-06 14:33:58 +090016#define PERCPU_MODULE_RESERVE 0
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#endif
18
Tejun Heo6a242902009-03-06 14:33:58 +090019#ifndef PERCPU_ENOUGH_ROOM
Jeremy Fitzhardingeb00742d2007-05-02 19:27:11 +020020#define PERCPU_ENOUGH_ROOM \
Tejun Heo6a242902009-03-06 14:33:58 +090021 (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \
22 PERCPU_MODULE_RESERVE)
23#endif
Jeremy Fitzhardingeb00742d2007-05-02 19:27:11 +020024
Jan Blunck632bbfe2006-09-25 23:30:53 -070025/*
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) (*({ \
Jan Blunck632bbfe2006-09-25 23:30:53 -070030 preempt_disable(); \
31 &__get_cpu_var(var); }))
Tejun Heof7b64fe2009-10-29 22:34:15 +090032
Rusty Russelle0fdb0e2009-10-29 22:34:15 +090033/*
34 * The weird & is necessary because sparse considers (void)(var) to be
35 * a direct dereference of percpu variable (var).
36 */
Tejun Heof7b64fe2009-10-29 22:34:15 +090037#define put_cpu_var(var) do { \
Rusty Russelle0fdb0e2009-10-29 22:34:15 +090038 (void)&(var); \
Tejun Heof7b64fe2009-10-29 22:34:15 +090039 preempt_enable(); \
40} while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
42#ifdef CONFIG_SMP
43
Tejun Heo8d408b42009-02-24 11:57:21 +090044/* minimum unit size, also is the maximum supported allocation size */
Tejun Heo6a242902009-03-06 14:33:58 +090045#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 10)
Tejun Heo8d408b42009-02-24 11:57:21 +090046
47/*
48 * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
Tejun Heo6b19b0c2009-03-06 14:33:59 +090049 * back on the first chunk for dynamic percpu allocation if arch is
50 * manually allocating and mapping it for faster access (as a part of
51 * large page mapping for example).
Tejun Heo8d408b42009-02-24 11:57:21 +090052 *
Tejun Heo6b19b0c2009-03-06 14:33:59 +090053 * The following values give between one and two pages of free space
54 * after typical minimal boot (2-way SMP, single disk and NIC) with
55 * both defconfig and a distro config on x86_64 and 32. More
56 * intelligent way to determine this would be nice.
Tejun Heo8d408b42009-02-24 11:57:21 +090057 */
Tejun Heo6b19b0c2009-03-06 14:33:59 +090058#if BITS_PER_LONG > 32
59#define PERCPU_DYNAMIC_RESERVE (20 << 10)
60#else
61#define PERCPU_DYNAMIC_RESERVE (12 << 10)
62#endif
Tejun Heo8d408b42009-02-24 11:57:21 +090063
Tejun Heofbf59bc2009-02-20 16:29:08 +090064extern void *pcpu_base_addr;
Tejun Heofb435d52009-08-14 15:00:51 +090065extern const unsigned long *pcpu_unit_offsets;
Tejun Heofbf59bc2009-02-20 16:29:08 +090066
Tejun Heofd1e8a12009-08-14 15:00:51 +090067struct pcpu_group_info {
68 int nr_units; /* aligned # of units */
69 unsigned long base_offset; /* base address offset */
70 unsigned int *cpu_map; /* unit->cpu map, empty
71 * entries contain NR_CPUS */
72};
73
74struct pcpu_alloc_info {
75 size_t static_size;
76 size_t reserved_size;
77 size_t dyn_size;
78 size_t unit_size;
79 size_t atom_size;
80 size_t alloc_size;
81 size_t __ai_size; /* internal, don't use */
82 int nr_groups; /* 0 if grouping unnecessary */
83 struct pcpu_group_info groups[];
84};
85
Tejun Heof58dc012009-08-14 15:00:50 +090086enum pcpu_fc {
87 PCPU_FC_AUTO,
88 PCPU_FC_EMBED,
89 PCPU_FC_PAGE,
Tejun Heof58dc012009-08-14 15:00:50 +090090
91 PCPU_FC_NR,
92};
93extern const char *pcpu_fc_names[PCPU_FC_NR];
94
95extern enum pcpu_fc pcpu_chosen_fc;
96
Tejun Heo3cbc8562009-08-14 15:00:50 +090097typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
98 size_t align);
Tejun Heod4b95f82009-07-04 08:10:59 +090099typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
100typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
Tejun Heoa530b792009-07-04 08:11:00 +0900101typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
Tejun Heofbf59bc2009-02-20 16:29:08 +0900102
Tejun Heofd1e8a12009-08-14 15:00:51 +0900103extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
104 int nr_units);
105extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
Tejun Heo033e48f2009-08-14 15:00:51 +0900106
Tejun Heofd1e8a12009-08-14 15:00:51 +0900107extern struct pcpu_alloc_info * __init pcpu_build_alloc_info(
108 size_t reserved_size, ssize_t dyn_size,
109 size_t atom_size,
110 pcpu_fc_cpu_distance_fn_t cpu_distance_fn);
111
Tejun Heofb435d52009-08-14 15:00:51 +0900112extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
113 void *base_addr);
Tejun Heo8d408b42009-02-24 11:57:21 +0900114
Tejun Heo08fc4582009-08-14 15:00:49 +0900115#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
Tejun Heoc8826dd2009-08-14 15:00:52 +0900116extern int __init pcpu_embed_first_chunk(size_t reserved_size, ssize_t dyn_size,
117 size_t atom_size,
118 pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
119 pcpu_fc_alloc_fn_t alloc_fn,
120 pcpu_fc_free_fn_t free_fn);
Tejun Heo08fc4582009-08-14 15:00:49 +0900121#endif
Tejun Heo66c3a752009-03-10 16:27:48 +0900122
Tejun Heo08fc4582009-08-14 15:00:49 +0900123#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heofb435d52009-08-14 15:00:51 +0900124extern int __init pcpu_page_first_chunk(size_t reserved_size,
Tejun Heod4b95f82009-07-04 08:10:59 +0900125 pcpu_fc_alloc_fn_t alloc_fn,
126 pcpu_fc_free_fn_t free_fn,
127 pcpu_fc_populate_pte_fn_t populate_pte_fn);
Tejun Heo08fc4582009-08-14 15:00:49 +0900128#endif
Tejun Heod4b95f82009-07-04 08:10:59 +0900129
Tejun Heofbf59bc2009-02-20 16:29:08 +0900130/*
131 * Use this to get to a cpu's version of the per-cpu object
132 * dynamically allocated. Non-atomic access to the current CPU's
133 * version should probably be combined with get_cpu()/put_cpu().
134 */
135#define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
136
Rusty Russelle0fdb0e2009-10-29 22:34:15 +0900137extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
138extern void __percpu *__alloc_percpu(size_t size, size_t align);
139extern void free_percpu(void __percpu *__pdata);
Tejun Heo10fad5e2010-03-10 18:57:54 +0900140extern bool is_kernel_percpu_address(unsigned long addr);
Vivek Goyal3b034b02009-11-24 15:50:03 +0900141extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
Tejun Heof2a82052009-02-20 16:29:08 +0900142
Tejun Heoe74e3962009-03-30 19:07:44 +0900143#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
144extern void __init setup_per_cpu_areas(void);
145#endif
146
Tejun Heof2a82052009-02-20 16:29:08 +0900147#else /* CONFIG_SMP */
148
149#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
150
Rusty Russelle0fdb0e2009-10-29 22:34:15 +0900151static inline void __percpu *__alloc_percpu(size_t size, size_t align)
Tejun Heof2a82052009-02-20 16:29:08 +0900152{
153 /*
154 * Can't easily make larger alignment work with kmalloc. WARN
155 * on it. Larger alignment should only be used for module
156 * percpu sections on SMP for which this path isn't used.
157 */
Tejun Heoe3176032009-02-26 10:54:17 +0900158 WARN_ON_ONCE(align > SMP_CACHE_BYTES);
Ingo Molnard2b02612009-02-25 14:36:45 +0100159 return kzalloc(size, GFP_KERNEL);
Tejun Heof2a82052009-02-20 16:29:08 +0900160}
161
Rusty Russelle0fdb0e2009-10-29 22:34:15 +0900162static inline void free_percpu(void __percpu *p)
Tejun Heof2a82052009-02-20 16:29:08 +0900163{
164 kfree(p);
165}
166
Tejun Heo10fad5e2010-03-10 18:57:54 +0900167/* can't distinguish from other static vars, always false */
168static inline bool is_kernel_percpu_address(unsigned long addr)
169{
170 return false;
171}
172
Tejun Heoee0a6ef2009-12-02 08:36:58 +0900173static inline phys_addr_t per_cpu_ptr_to_phys(void *addr)
174{
175 return __pa(addr);
176}
177
Tejun Heoe74e3962009-03-30 19:07:44 +0900178static inline void __init setup_per_cpu_areas(void) { }
179
Tejun Heoa76761b2009-07-15 23:35:14 +0900180static inline void *pcpu_lpage_remapped(void *kaddr)
181{
182 return NULL;
183}
184
Tejun Heof2a82052009-02-20 16:29:08 +0900185#endif /* CONFIG_SMP */
186
Tejun Heo64ef2912009-10-29 22:34:12 +0900187#define alloc_percpu(type) \
Rusty Russelle0fdb0e2009-10-29 22:34:15 +0900188 (typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
Tejun Heof2a82052009-02-20 16:29:08 +0900189
Tejun Heo066123a2009-04-10 12:02:40 -0700190/*
191 * Optional methods for optimized non-lvalue per-cpu variable access.
192 *
193 * @var can be a percpu variable or a field of it and its size should
194 * equal char, int or long. percpu_read() evaluates to a lvalue and
195 * all others to void.
196 *
197 * These operations are guaranteed to be atomic w.r.t. preemption.
198 * The generic versions use plain get/put_cpu_var(). Archs are
199 * encouraged to implement single-instruction alternatives which don't
200 * require preemption protection.
201 */
202#ifndef percpu_read
203# define percpu_read(var) \
204 ({ \
Tejun Heof7b64fe2009-10-29 22:34:15 +0900205 typeof(var) *pr_ptr__ = &(var); \
206 typeof(var) pr_ret__; \
207 pr_ret__ = get_cpu_var(*pr_ptr__); \
208 put_cpu_var(*pr_ptr__); \
209 pr_ret__; \
Tejun Heo066123a2009-04-10 12:02:40 -0700210 })
211#endif
212
213#define __percpu_generic_to_op(var, val, op) \
214do { \
Tejun Heof7b64fe2009-10-29 22:34:15 +0900215 typeof(var) *pgto_ptr__ = &(var); \
216 get_cpu_var(*pgto_ptr__) op val; \
217 put_cpu_var(*pgto_ptr__); \
Tejun Heo066123a2009-04-10 12:02:40 -0700218} while (0)
219
220#ifndef percpu_write
221# define percpu_write(var, val) __percpu_generic_to_op(var, (val), =)
222#endif
223
224#ifndef percpu_add
225# define percpu_add(var, val) __percpu_generic_to_op(var, (val), +=)
226#endif
227
228#ifndef percpu_sub
229# define percpu_sub(var, val) __percpu_generic_to_op(var, (val), -=)
230#endif
231
232#ifndef percpu_and
233# define percpu_and(var, val) __percpu_generic_to_op(var, (val), &=)
234#endif
235
236#ifndef percpu_or
237# define percpu_or(var, val) __percpu_generic_to_op(var, (val), |=)
238#endif
239
240#ifndef percpu_xor
241# define percpu_xor(var, val) __percpu_generic_to_op(var, (val), ^=)
242#endif
243
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900244/*
245 * Branching function to split up a function into a set of functions that
246 * are called for different scalar sizes of the objects handled.
247 */
248
249extern void __bad_size_call_parameter(void);
250
Tejun Heo0f5e4812009-10-29 22:34:12 +0900251#define __pcpu_size_call_return(stem, variable) \
252({ typeof(variable) pscr_ret__; \
Tejun Heo545695f2009-10-29 22:34:15 +0900253 __verify_pcpu_ptr(&(variable)); \
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900254 switch(sizeof(variable)) { \
Tejun Heo0f5e4812009-10-29 22:34:12 +0900255 case 1: pscr_ret__ = stem##1(variable);break; \
256 case 2: pscr_ret__ = stem##2(variable);break; \
257 case 4: pscr_ret__ = stem##4(variable);break; \
258 case 8: pscr_ret__ = stem##8(variable);break; \
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900259 default: \
260 __bad_size_call_parameter();break; \
261 } \
Tejun Heo0f5e4812009-10-29 22:34:12 +0900262 pscr_ret__; \
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900263})
264
Tejun Heo0f5e4812009-10-29 22:34:12 +0900265#define __pcpu_size_call(stem, variable, ...) \
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900266do { \
Tejun Heo545695f2009-10-29 22:34:15 +0900267 __verify_pcpu_ptr(&(variable)); \
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900268 switch(sizeof(variable)) { \
269 case 1: stem##1(variable, __VA_ARGS__);break; \
270 case 2: stem##2(variable, __VA_ARGS__);break; \
271 case 4: stem##4(variable, __VA_ARGS__);break; \
272 case 8: stem##8(variable, __VA_ARGS__);break; \
273 default: \
274 __bad_size_call_parameter();break; \
275 } \
276} while (0)
277
278/*
279 * Optimized manipulation for memory allocated through the per cpu
Rusty Russelldd17c8f2009-10-29 22:34:15 +0900280 * allocator or for addresses of per cpu variables.
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900281 *
282 * These operation guarantee exclusivity of access for other operations
283 * on the *same* processor. The assumption is that per cpu data is only
284 * accessed by a single processor instance (the current one).
285 *
286 * The first group is used for accesses that must be done in a
287 * preemption safe way since we know that the context is not preempt
288 * safe. Interrupts may occur. If the interrupt modifies the variable
289 * too then RMW actions will not be reliable.
290 *
291 * The arch code can provide optimized functions in two ways:
292 *
293 * 1. Override the function completely. F.e. define this_cpu_add().
294 * The arch must then ensure that the various scalar format passed
295 * are handled correctly.
296 *
297 * 2. Provide functions for certain scalar sizes. F.e. provide
298 * this_cpu_add_2() to provide per cpu atomic operations for 2 byte
299 * sized RMW actions. If arch code does not provide operations for
300 * a scalar size then the fallback in the generic code will be
301 * used.
302 */
303
304#define _this_cpu_generic_read(pcp) \
305({ typeof(pcp) ret__; \
306 preempt_disable(); \
307 ret__ = *this_cpu_ptr(&(pcp)); \
308 preempt_enable(); \
309 ret__; \
310})
311
312#ifndef this_cpu_read
313# ifndef this_cpu_read_1
314# define this_cpu_read_1(pcp) _this_cpu_generic_read(pcp)
315# endif
316# ifndef this_cpu_read_2
317# define this_cpu_read_2(pcp) _this_cpu_generic_read(pcp)
318# endif
319# ifndef this_cpu_read_4
320# define this_cpu_read_4(pcp) _this_cpu_generic_read(pcp)
321# endif
322# ifndef this_cpu_read_8
323# define this_cpu_read_8(pcp) _this_cpu_generic_read(pcp)
324# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900325# define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900326#endif
327
328#define _this_cpu_generic_to_op(pcp, val, op) \
329do { \
330 preempt_disable(); \
Tejun Heof7b64fe2009-10-29 22:34:15 +0900331 *__this_cpu_ptr(&(pcp)) op val; \
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900332 preempt_enable(); \
333} while (0)
334
335#ifndef this_cpu_write
336# ifndef this_cpu_write_1
337# define this_cpu_write_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
338# endif
339# ifndef this_cpu_write_2
340# define this_cpu_write_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
341# endif
342# ifndef this_cpu_write_4
343# define this_cpu_write_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
344# endif
345# ifndef this_cpu_write_8
346# define this_cpu_write_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
347# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900348# define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900349#endif
350
351#ifndef this_cpu_add
352# ifndef this_cpu_add_1
353# define this_cpu_add_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
354# endif
355# ifndef this_cpu_add_2
356# define this_cpu_add_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
357# endif
358# ifndef this_cpu_add_4
359# define this_cpu_add_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
360# endif
361# ifndef this_cpu_add_8
362# define this_cpu_add_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
363# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900364# define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900365#endif
366
367#ifndef this_cpu_sub
368# define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(val))
369#endif
370
371#ifndef this_cpu_inc
372# define this_cpu_inc(pcp) this_cpu_add((pcp), 1)
373#endif
374
375#ifndef this_cpu_dec
376# define this_cpu_dec(pcp) this_cpu_sub((pcp), 1)
377#endif
378
379#ifndef this_cpu_and
380# ifndef this_cpu_and_1
381# define this_cpu_and_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
382# endif
383# ifndef this_cpu_and_2
384# define this_cpu_and_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
385# endif
386# ifndef this_cpu_and_4
387# define this_cpu_and_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
388# endif
389# ifndef this_cpu_and_8
390# define this_cpu_and_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
391# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900392# define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900393#endif
394
395#ifndef this_cpu_or
396# ifndef this_cpu_or_1
397# define this_cpu_or_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
398# endif
399# ifndef this_cpu_or_2
400# define this_cpu_or_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
401# endif
402# ifndef this_cpu_or_4
403# define this_cpu_or_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
404# endif
405# ifndef this_cpu_or_8
406# define this_cpu_or_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
407# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900408# define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900409#endif
410
411#ifndef this_cpu_xor
412# ifndef this_cpu_xor_1
413# define this_cpu_xor_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
414# endif
415# ifndef this_cpu_xor_2
416# define this_cpu_xor_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
417# endif
418# ifndef this_cpu_xor_4
419# define this_cpu_xor_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
420# endif
421# ifndef this_cpu_xor_8
422# define this_cpu_xor_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
423# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900424# define this_cpu_xor(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900425#endif
426
427/*
428 * Generic percpu operations that do not require preemption handling.
429 * Either we do not care about races or the caller has the
430 * responsibility of handling preemptions issues. Arch code can still
431 * override these instructions since the arch per cpu code may be more
432 * efficient and may actually get race freeness for free (that is the
433 * case for x86 for example).
434 *
435 * If there is no other protection through preempt disable and/or
436 * disabling interupts then one of these RMW operations can show unexpected
437 * behavior because the execution thread was rescheduled on another processor
438 * or an interrupt occurred and the same percpu variable was modified from
439 * the interrupt context.
440 */
441#ifndef __this_cpu_read
442# ifndef __this_cpu_read_1
443# define __this_cpu_read_1(pcp) (*__this_cpu_ptr(&(pcp)))
444# endif
445# ifndef __this_cpu_read_2
446# define __this_cpu_read_2(pcp) (*__this_cpu_ptr(&(pcp)))
447# endif
448# ifndef __this_cpu_read_4
449# define __this_cpu_read_4(pcp) (*__this_cpu_ptr(&(pcp)))
450# endif
451# ifndef __this_cpu_read_8
452# define __this_cpu_read_8(pcp) (*__this_cpu_ptr(&(pcp)))
453# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900454# define __this_cpu_read(pcp) __pcpu_size_call_return(__this_cpu_read_, (pcp))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900455#endif
456
457#define __this_cpu_generic_to_op(pcp, val, op) \
458do { \
459 *__this_cpu_ptr(&(pcp)) op val; \
460} while (0)
461
462#ifndef __this_cpu_write
463# ifndef __this_cpu_write_1
464# define __this_cpu_write_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
465# endif
466# ifndef __this_cpu_write_2
467# define __this_cpu_write_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
468# endif
469# ifndef __this_cpu_write_4
470# define __this_cpu_write_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
471# endif
472# ifndef __this_cpu_write_8
473# define __this_cpu_write_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
474# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900475# define __this_cpu_write(pcp, val) __pcpu_size_call(__this_cpu_write_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900476#endif
477
478#ifndef __this_cpu_add
479# ifndef __this_cpu_add_1
480# define __this_cpu_add_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
481# endif
482# ifndef __this_cpu_add_2
483# define __this_cpu_add_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
484# endif
485# ifndef __this_cpu_add_4
486# define __this_cpu_add_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
487# endif
488# ifndef __this_cpu_add_8
489# define __this_cpu_add_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
490# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900491# define __this_cpu_add(pcp, val) __pcpu_size_call(__this_cpu_add_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900492#endif
493
494#ifndef __this_cpu_sub
495# define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(val))
496#endif
497
498#ifndef __this_cpu_inc
499# define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1)
500#endif
501
502#ifndef __this_cpu_dec
503# define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1)
504#endif
505
506#ifndef __this_cpu_and
507# ifndef __this_cpu_and_1
508# define __this_cpu_and_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
509# endif
510# ifndef __this_cpu_and_2
511# define __this_cpu_and_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
512# endif
513# ifndef __this_cpu_and_4
514# define __this_cpu_and_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
515# endif
516# ifndef __this_cpu_and_8
517# define __this_cpu_and_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
518# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900519# define __this_cpu_and(pcp, val) __pcpu_size_call(__this_cpu_and_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900520#endif
521
522#ifndef __this_cpu_or
523# ifndef __this_cpu_or_1
524# define __this_cpu_or_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
525# endif
526# ifndef __this_cpu_or_2
527# define __this_cpu_or_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
528# endif
529# ifndef __this_cpu_or_4
530# define __this_cpu_or_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
531# endif
532# ifndef __this_cpu_or_8
533# define __this_cpu_or_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
534# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900535# define __this_cpu_or(pcp, val) __pcpu_size_call(__this_cpu_or_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900536#endif
537
538#ifndef __this_cpu_xor
539# ifndef __this_cpu_xor_1
540# define __this_cpu_xor_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
541# endif
542# ifndef __this_cpu_xor_2
543# define __this_cpu_xor_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
544# endif
545# ifndef __this_cpu_xor_4
546# define __this_cpu_xor_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
547# endif
548# ifndef __this_cpu_xor_8
549# define __this_cpu_xor_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
550# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900551# define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900552#endif
553
554/*
555 * IRQ safe versions of the per cpu RMW operations. Note that these operations
556 * are *not* safe against modification of the same variable from another
557 * processors (which one gets when using regular atomic operations)
558 . They are guaranteed to be atomic vs. local interrupts and
559 * preemption only.
560 */
561#define irqsafe_cpu_generic_to_op(pcp, val, op) \
562do { \
563 unsigned long flags; \
564 local_irq_save(flags); \
565 *__this_cpu_ptr(&(pcp)) op val; \
566 local_irq_restore(flags); \
567} while (0)
568
569#ifndef irqsafe_cpu_add
570# ifndef irqsafe_cpu_add_1
571# define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
572# endif
573# ifndef irqsafe_cpu_add_2
574# define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
575# endif
576# ifndef irqsafe_cpu_add_4
577# define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
578# endif
579# ifndef irqsafe_cpu_add_8
580# define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
581# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900582# define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900583#endif
584
585#ifndef irqsafe_cpu_sub
586# define irqsafe_cpu_sub(pcp, val) irqsafe_cpu_add((pcp), -(val))
587#endif
588
589#ifndef irqsafe_cpu_inc
590# define irqsafe_cpu_inc(pcp) irqsafe_cpu_add((pcp), 1)
591#endif
592
593#ifndef irqsafe_cpu_dec
594# define irqsafe_cpu_dec(pcp) irqsafe_cpu_sub((pcp), 1)
595#endif
596
597#ifndef irqsafe_cpu_and
598# ifndef irqsafe_cpu_and_1
599# define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
600# endif
601# ifndef irqsafe_cpu_and_2
602# define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
603# endif
604# ifndef irqsafe_cpu_and_4
605# define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
606# endif
607# ifndef irqsafe_cpu_and_8
608# define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
609# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900610# define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900611#endif
612
613#ifndef irqsafe_cpu_or
614# ifndef irqsafe_cpu_or_1
615# define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
616# endif
617# ifndef irqsafe_cpu_or_2
618# define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
619# endif
620# ifndef irqsafe_cpu_or_4
621# define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
622# endif
623# ifndef irqsafe_cpu_or_8
624# define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
625# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900626# define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900627#endif
628
629#ifndef irqsafe_cpu_xor
630# ifndef irqsafe_cpu_xor_1
631# define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
632# endif
633# ifndef irqsafe_cpu_xor_2
634# define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
635# endif
636# ifndef irqsafe_cpu_xor_4
637# define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
638# endif
639# ifndef irqsafe_cpu_xor_8
640# define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
641# endif
Tejun Heo0f5e4812009-10-29 22:34:12 +0900642# define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val))
Christoph Lameter7340a0b2009-10-03 19:48:22 +0900643#endif
644
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645#endif /* __LINUX_PERCPU_H */