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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_PERCPU_H
3#define __LINUX_PERCPU_H
4
5#include <linux/mmdebug.h>
6#include <linux/preempt.h>
7#include <linux/smp.h>
8#include <linux/cpumask.h>
9#include <linux/printk.h>
10#include <linux/pfn.h>
11#include <linux/init.h>
12
13#include <asm/percpu.h>
14
15/* enough to cover all DEFINE_PER_CPUs in modules */
16#ifdef CONFIG_MODULES
17#define PERCPU_MODULE_RESERVE (8 << 10)
18#else
19#define PERCPU_MODULE_RESERVE 0
20#endif
21
22/* minimum unit size, also is the maximum supported allocation size */
23#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10)
24
25/* minimum allocation size and shift in bytes */
26#define PCPU_MIN_ALLOC_SHIFT 2
27#define PCPU_MIN_ALLOC_SIZE (1 << PCPU_MIN_ALLOC_SHIFT)
28
29/*
30 * The PCPU_BITMAP_BLOCK_SIZE must be the same size as PAGE_SIZE as the
31 * updating of hints is used to manage the nr_empty_pop_pages in both
32 * the chunk and globally.
33 */
34#define PCPU_BITMAP_BLOCK_SIZE PAGE_SIZE
35#define PCPU_BITMAP_BLOCK_BITS (PCPU_BITMAP_BLOCK_SIZE >> \
36 PCPU_MIN_ALLOC_SHIFT)
37
38/*
39 * Percpu allocator can serve percpu allocations before slab is
40 * initialized which allows slab to depend on the percpu allocator.
41 * The following two parameters decide how much resource to
42 * preallocate for this. Keep PERCPU_DYNAMIC_RESERVE equal to or
43 * larger than PERCPU_DYNAMIC_EARLY_SIZE.
44 */
45#define PERCPU_DYNAMIC_EARLY_SLOTS 128
46#define PERCPU_DYNAMIC_EARLY_SIZE (12 << 10)
47
48/*
49 * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
50 * back on the first chunk for dynamic percpu allocation if arch is
51 * manually allocating and mapping it for faster access (as a part of
52 * large page mapping for example).
53 *
54 * The following values give between one and two pages of free space
55 * after typical minimal boot (2-way SMP, single disk and NIC) with
56 * both defconfig and a distro config on x86_64 and 32. More
57 * intelligent way to determine this would be nice.
58 */
59#if BITS_PER_LONG > 32
60#define PERCPU_DYNAMIC_RESERVE (28 << 10)
61#else
62#define PERCPU_DYNAMIC_RESERVE (20 << 10)
63#endif
64
65extern void *pcpu_base_addr;
66extern const unsigned long *pcpu_unit_offsets;
67
68struct pcpu_group_info {
69 int nr_units; /* aligned # of units */
70 unsigned long base_offset; /* base address offset */
71 unsigned int *cpu_map; /* unit->cpu map, empty
72 * entries contain NR_CPUS */
73};
74
75struct pcpu_alloc_info {
76 size_t static_size;
77 size_t reserved_size;
78 size_t dyn_size;
79 size_t unit_size;
80 size_t atom_size;
81 size_t alloc_size;
82 size_t __ai_size; /* internal, don't use */
83 int nr_groups; /* 0 if grouping unnecessary */
84 struct pcpu_group_info groups[];
85};
86
87enum pcpu_fc {
88 PCPU_FC_AUTO,
89 PCPU_FC_EMBED,
90 PCPU_FC_PAGE,
91
92 PCPU_FC_NR,
93};
94extern const char * const pcpu_fc_names[PCPU_FC_NR];
95
96extern enum pcpu_fc pcpu_chosen_fc;
97
98typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
99 size_t align);
100typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
101typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
102typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
103
104extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
105 int nr_units);
106extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
107
108extern void __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
109 void *base_addr);
110
111#ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
112extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
113 size_t atom_size,
114 pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
115 pcpu_fc_alloc_fn_t alloc_fn,
116 pcpu_fc_free_fn_t free_fn);
117#endif
118
119#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
120extern int __init pcpu_page_first_chunk(size_t reserved_size,
121 pcpu_fc_alloc_fn_t alloc_fn,
122 pcpu_fc_free_fn_t free_fn,
123 pcpu_fc_populate_pte_fn_t populate_pte_fn);
124#endif
125
126extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
127extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr);
128extern bool is_kernel_percpu_address(unsigned long addr);
129
130#if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
131extern void __init setup_per_cpu_areas(void);
132#endif
133
134extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp);
135extern void __percpu *__alloc_percpu(size_t size, size_t align);
136extern void free_percpu(void __percpu *__pdata);
137extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
138
139#define alloc_percpu_gfp(type, gfp) \
140 (typeof(type) __percpu *)__alloc_percpu_gfp(sizeof(type), \
141 __alignof__(type), gfp)
142#define alloc_percpu(type) \
143 (typeof(type) __percpu *)__alloc_percpu(sizeof(type), \
144 __alignof__(type))
145
146extern unsigned long pcpu_nr_pages(void);
147
148#endif /* __LINUX_PERCPU_H */
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
81extern void *pcpu_base_addr;
82extern const unsigned long *pcpu_unit_offsets;
83
84struct 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
91struct 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
103enum pcpu_fc {
104 PCPU_FC_AUTO,
105 PCPU_FC_EMBED,
106 PCPU_FC_PAGE,
107
108 PCPU_FC_NR,
109};
110extern const char *pcpu_fc_names[PCPU_FC_NR];
111
112extern enum pcpu_fc pcpu_chosen_fc;
113
114typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
115 size_t align);
116typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
117typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
118typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
119
120extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
121 int nr_units);
122extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
123
124extern 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
128extern 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
136extern 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
153extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
154extern bool is_kernel_percpu_address(unsigned long addr);
155
156#if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
157extern void __init setup_per_cpu_areas(void);
158#endif
159extern void __init percpu_init_late(void);
160
161extern void __percpu *__alloc_percpu(size_t size, size_t align);
162extern void free_percpu(void __percpu *__pdata);
163extern 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 * Branching function to split up a function into a set of functions that
170 * are called for different scalar sizes of the objects handled.
171 */
172
173extern void __bad_size_call_parameter(void);
174
175#define __pcpu_size_call_return(stem, variable) \
176({ typeof(variable) pscr_ret__; \
177 __verify_pcpu_ptr(&(variable)); \
178 switch(sizeof(variable)) { \
179 case 1: pscr_ret__ = stem##1(variable);break; \
180 case 2: pscr_ret__ = stem##2(variable);break; \
181 case 4: pscr_ret__ = stem##4(variable);break; \
182 case 8: pscr_ret__ = stem##8(variable);break; \
183 default: \
184 __bad_size_call_parameter();break; \
185 } \
186 pscr_ret__; \
187})
188
189#define __pcpu_size_call_return2(stem, variable, ...) \
190({ \
191 typeof(variable) pscr2_ret__; \
192 __verify_pcpu_ptr(&(variable)); \
193 switch(sizeof(variable)) { \
194 case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \
195 case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break; \
196 case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break; \
197 case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break; \
198 default: \
199 __bad_size_call_parameter(); break; \
200 } \
201 pscr2_ret__; \
202})
203
204/*
205 * Special handling for cmpxchg_double. cmpxchg_double is passed two
206 * percpu variables. The first has to be aligned to a double word
207 * boundary and the second has to follow directly thereafter.
208 * We enforce this on all architectures even if they don't support
209 * a double cmpxchg instruction, since it's a cheap requirement, and it
210 * avoids breaking the requirement for architectures with the instruction.
211 */
212#define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \
213({ \
214 bool pdcrb_ret__; \
215 __verify_pcpu_ptr(&pcp1); \
216 BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \
217 VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1))); \
218 VM_BUG_ON((unsigned long)(&pcp2) != \
219 (unsigned long)(&pcp1) + sizeof(pcp1)); \
220 switch(sizeof(pcp1)) { \
221 case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \
222 case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \
223 case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \
224 case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \
225 default: \
226 __bad_size_call_parameter(); break; \
227 } \
228 pdcrb_ret__; \
229})
230
231#define __pcpu_size_call(stem, variable, ...) \
232do { \
233 __verify_pcpu_ptr(&(variable)); \
234 switch(sizeof(variable)) { \
235 case 1: stem##1(variable, __VA_ARGS__);break; \
236 case 2: stem##2(variable, __VA_ARGS__);break; \
237 case 4: stem##4(variable, __VA_ARGS__);break; \
238 case 8: stem##8(variable, __VA_ARGS__);break; \
239 default: \
240 __bad_size_call_parameter();break; \
241 } \
242} while (0)
243
244/*
245 * Optimized manipulation for memory allocated through the per cpu
246 * allocator or for addresses of per cpu variables.
247 *
248 * These operation guarantee exclusivity of access for other operations
249 * on the *same* processor. The assumption is that per cpu data is only
250 * accessed by a single processor instance (the current one).
251 *
252 * The first group is used for accesses that must be done in a
253 * preemption safe way since we know that the context is not preempt
254 * safe. Interrupts may occur. If the interrupt modifies the variable
255 * too then RMW actions will not be reliable.
256 *
257 * The arch code can provide optimized functions in two ways:
258 *
259 * 1. Override the function completely. F.e. define this_cpu_add().
260 * The arch must then ensure that the various scalar format passed
261 * are handled correctly.
262 *
263 * 2. Provide functions for certain scalar sizes. F.e. provide
264 * this_cpu_add_2() to provide per cpu atomic operations for 2 byte
265 * sized RMW actions. If arch code does not provide operations for
266 * a scalar size then the fallback in the generic code will be
267 * used.
268 */
269
270#define _this_cpu_generic_read(pcp) \
271({ typeof(pcp) ret__; \
272 preempt_disable(); \
273 ret__ = *this_cpu_ptr(&(pcp)); \
274 preempt_enable(); \
275 ret__; \
276})
277
278#ifndef this_cpu_read
279# ifndef this_cpu_read_1
280# define this_cpu_read_1(pcp) _this_cpu_generic_read(pcp)
281# endif
282# ifndef this_cpu_read_2
283# define this_cpu_read_2(pcp) _this_cpu_generic_read(pcp)
284# endif
285# ifndef this_cpu_read_4
286# define this_cpu_read_4(pcp) _this_cpu_generic_read(pcp)
287# endif
288# ifndef this_cpu_read_8
289# define this_cpu_read_8(pcp) _this_cpu_generic_read(pcp)
290# endif
291# define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp))
292#endif
293
294#define _this_cpu_generic_to_op(pcp, val, op) \
295do { \
296 unsigned long flags; \
297 raw_local_irq_save(flags); \
298 *__this_cpu_ptr(&(pcp)) op val; \
299 raw_local_irq_restore(flags); \
300} while (0)
301
302#ifndef this_cpu_write
303# ifndef this_cpu_write_1
304# define this_cpu_write_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
305# endif
306# ifndef this_cpu_write_2
307# define this_cpu_write_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
308# endif
309# ifndef this_cpu_write_4
310# define this_cpu_write_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
311# endif
312# ifndef this_cpu_write_8
313# define this_cpu_write_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), =)
314# endif
315# define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val))
316#endif
317
318#ifndef this_cpu_add
319# ifndef this_cpu_add_1
320# define this_cpu_add_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
321# endif
322# ifndef this_cpu_add_2
323# define this_cpu_add_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
324# endif
325# ifndef this_cpu_add_4
326# define this_cpu_add_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
327# endif
328# ifndef this_cpu_add_8
329# define this_cpu_add_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=)
330# endif
331# define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val))
332#endif
333
334#ifndef this_cpu_sub
335# define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(val))
336#endif
337
338#ifndef this_cpu_inc
339# define this_cpu_inc(pcp) this_cpu_add((pcp), 1)
340#endif
341
342#ifndef this_cpu_dec
343# define this_cpu_dec(pcp) this_cpu_sub((pcp), 1)
344#endif
345
346#ifndef this_cpu_and
347# ifndef this_cpu_and_1
348# define this_cpu_and_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
349# endif
350# ifndef this_cpu_and_2
351# define this_cpu_and_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
352# endif
353# ifndef this_cpu_and_4
354# define this_cpu_and_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
355# endif
356# ifndef this_cpu_and_8
357# define this_cpu_and_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=)
358# endif
359# define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val))
360#endif
361
362#ifndef this_cpu_or
363# ifndef this_cpu_or_1
364# define this_cpu_or_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
365# endif
366# ifndef this_cpu_or_2
367# define this_cpu_or_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
368# endif
369# ifndef this_cpu_or_4
370# define this_cpu_or_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
371# endif
372# ifndef this_cpu_or_8
373# define this_cpu_or_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=)
374# endif
375# define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
376#endif
377
378#ifndef this_cpu_xor
379# ifndef this_cpu_xor_1
380# define this_cpu_xor_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
381# endif
382# ifndef this_cpu_xor_2
383# define this_cpu_xor_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
384# endif
385# ifndef this_cpu_xor_4
386# define this_cpu_xor_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
387# endif
388# ifndef this_cpu_xor_8
389# define this_cpu_xor_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=)
390# endif
391# define this_cpu_xor(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val))
392#endif
393
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
405#ifndef this_cpu_add_return
406# ifndef this_cpu_add_return_1
407# define this_cpu_add_return_1(pcp, val) _this_cpu_generic_add_return(pcp, val)
408# endif
409# ifndef this_cpu_add_return_2
410# define this_cpu_add_return_2(pcp, val) _this_cpu_generic_add_return(pcp, val)
411# endif
412# ifndef this_cpu_add_return_4
413# define this_cpu_add_return_4(pcp, val) _this_cpu_generic_add_return(pcp, val)
414# endif
415# ifndef this_cpu_add_return_8
416# define this_cpu_add_return_8(pcp, val) _this_cpu_generic_add_return(pcp, val)
417# endif
418# define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
419#endif
420
421#define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(val))
422#define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1)
423#define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1)
424
425#define _this_cpu_generic_xchg(pcp, nval) \
426({ typeof(pcp) ret__; \
427 unsigned long flags; \
428 raw_local_irq_save(flags); \
429 ret__ = __this_cpu_read(pcp); \
430 __this_cpu_write(pcp, nval); \
431 raw_local_irq_restore(flags); \
432 ret__; \
433})
434
435#ifndef this_cpu_xchg
436# ifndef this_cpu_xchg_1
437# define this_cpu_xchg_1(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
438# endif
439# ifndef this_cpu_xchg_2
440# define this_cpu_xchg_2(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
441# endif
442# ifndef this_cpu_xchg_4
443# define this_cpu_xchg_4(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
444# endif
445# ifndef this_cpu_xchg_8
446# define this_cpu_xchg_8(pcp, nval) _this_cpu_generic_xchg(pcp, nval)
447# endif
448# define this_cpu_xchg(pcp, nval) \
449 __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval)
450#endif
451
452#define _this_cpu_generic_cmpxchg(pcp, oval, nval) \
453({ \
454 typeof(pcp) ret__; \
455 unsigned long flags; \
456 raw_local_irq_save(flags); \
457 ret__ = __this_cpu_read(pcp); \
458 if (ret__ == (oval)) \
459 __this_cpu_write(pcp, nval); \
460 raw_local_irq_restore(flags); \
461 ret__; \
462})
463
464#ifndef this_cpu_cmpxchg
465# ifndef this_cpu_cmpxchg_1
466# define this_cpu_cmpxchg_1(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
467# endif
468# ifndef this_cpu_cmpxchg_2
469# define this_cpu_cmpxchg_2(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
470# endif
471# ifndef this_cpu_cmpxchg_4
472# define this_cpu_cmpxchg_4(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
473# endif
474# ifndef this_cpu_cmpxchg_8
475# define this_cpu_cmpxchg_8(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval)
476# endif
477# define this_cpu_cmpxchg(pcp, oval, nval) \
478 __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
479#endif
480
481/*
482 * cmpxchg_double replaces two adjacent scalars at once. The first
483 * two parameters are per cpu variables which have to be of the same
484 * size. A truth value is returned to indicate success or failure
485 * (since a double register result is difficult to handle). There is
486 * very limited hardware support for these operations, so only certain
487 * sizes may work.
488 */
489#define _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
490({ \
491 int ret__; \
492 unsigned long flags; \
493 raw_local_irq_save(flags); \
494 ret__ = __this_cpu_generic_cmpxchg_double(pcp1, pcp2, \
495 oval1, oval2, nval1, nval2); \
496 raw_local_irq_restore(flags); \
497 ret__; \
498})
499
500#ifndef this_cpu_cmpxchg_double
501# ifndef this_cpu_cmpxchg_double_1
502# define this_cpu_cmpxchg_double_1(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_2
506# define this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \
507 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
508# endif
509# ifndef this_cpu_cmpxchg_double_4
510# define this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \
511 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
512# endif
513# ifndef this_cpu_cmpxchg_double_8
514# define this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \
515 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
516# endif
517# define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
518 __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
519#endif
520
521/*
522 * Generic percpu operations for context that are safe from preemption/interrupts.
523 * Either we do not care about races or the caller has the
524 * responsibility of handling preemption/interrupt issues. Arch code can still
525 * override these instructions since the arch per cpu code may be more
526 * efficient and may actually get race freeness for free (that is the
527 * case for x86 for example).
528 *
529 * If there is no other protection through preempt disable and/or
530 * disabling interupts then one of these RMW operations can show unexpected
531 * behavior because the execution thread was rescheduled on another processor
532 * or an interrupt occurred and the same percpu variable was modified from
533 * the interrupt context.
534 */
535#ifndef __this_cpu_read
536# ifndef __this_cpu_read_1
537# define __this_cpu_read_1(pcp) (*__this_cpu_ptr(&(pcp)))
538# endif
539# ifndef __this_cpu_read_2
540# define __this_cpu_read_2(pcp) (*__this_cpu_ptr(&(pcp)))
541# endif
542# ifndef __this_cpu_read_4
543# define __this_cpu_read_4(pcp) (*__this_cpu_ptr(&(pcp)))
544# endif
545# ifndef __this_cpu_read_8
546# define __this_cpu_read_8(pcp) (*__this_cpu_ptr(&(pcp)))
547# endif
548# define __this_cpu_read(pcp) __pcpu_size_call_return(__this_cpu_read_, (pcp))
549#endif
550
551#define __this_cpu_generic_to_op(pcp, val, op) \
552do { \
553 *__this_cpu_ptr(&(pcp)) op val; \
554} while (0)
555
556#ifndef __this_cpu_write
557# ifndef __this_cpu_write_1
558# define __this_cpu_write_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
559# endif
560# ifndef __this_cpu_write_2
561# define __this_cpu_write_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
562# endif
563# ifndef __this_cpu_write_4
564# define __this_cpu_write_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
565# endif
566# ifndef __this_cpu_write_8
567# define __this_cpu_write_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), =)
568# endif
569# define __this_cpu_write(pcp, val) __pcpu_size_call(__this_cpu_write_, (pcp), (val))
570#endif
571
572#ifndef __this_cpu_add
573# ifndef __this_cpu_add_1
574# define __this_cpu_add_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
575# endif
576# ifndef __this_cpu_add_2
577# define __this_cpu_add_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
578# endif
579# ifndef __this_cpu_add_4
580# define __this_cpu_add_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
581# endif
582# ifndef __this_cpu_add_8
583# define __this_cpu_add_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=)
584# endif
585# define __this_cpu_add(pcp, val) __pcpu_size_call(__this_cpu_add_, (pcp), (val))
586#endif
587
588#ifndef __this_cpu_sub
589# define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(val))
590#endif
591
592#ifndef __this_cpu_inc
593# define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1)
594#endif
595
596#ifndef __this_cpu_dec
597# define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1)
598#endif
599
600#ifndef __this_cpu_and
601# ifndef __this_cpu_and_1
602# define __this_cpu_and_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
603# endif
604# ifndef __this_cpu_and_2
605# define __this_cpu_and_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
606# endif
607# ifndef __this_cpu_and_4
608# define __this_cpu_and_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
609# endif
610# ifndef __this_cpu_and_8
611# define __this_cpu_and_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=)
612# endif
613# define __this_cpu_and(pcp, val) __pcpu_size_call(__this_cpu_and_, (pcp), (val))
614#endif
615
616#ifndef __this_cpu_or
617# ifndef __this_cpu_or_1
618# define __this_cpu_or_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
619# endif
620# ifndef __this_cpu_or_2
621# define __this_cpu_or_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
622# endif
623# ifndef __this_cpu_or_4
624# define __this_cpu_or_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
625# endif
626# ifndef __this_cpu_or_8
627# define __this_cpu_or_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=)
628# endif
629# define __this_cpu_or(pcp, val) __pcpu_size_call(__this_cpu_or_, (pcp), (val))
630#endif
631
632#ifndef __this_cpu_xor
633# ifndef __this_cpu_xor_1
634# define __this_cpu_xor_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
635# endif
636# ifndef __this_cpu_xor_2
637# define __this_cpu_xor_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
638# endif
639# ifndef __this_cpu_xor_4
640# define __this_cpu_xor_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
641# endif
642# ifndef __this_cpu_xor_8
643# define __this_cpu_xor_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=)
644# endif
645# define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
646#endif
647
648#define __this_cpu_generic_add_return(pcp, val) \
649({ \
650 __this_cpu_add(pcp, val); \
651 __this_cpu_read(pcp); \
652})
653
654#ifndef __this_cpu_add_return
655# ifndef __this_cpu_add_return_1
656# define __this_cpu_add_return_1(pcp, val) __this_cpu_generic_add_return(pcp, val)
657# endif
658# ifndef __this_cpu_add_return_2
659# define __this_cpu_add_return_2(pcp, val) __this_cpu_generic_add_return(pcp, val)
660# endif
661# ifndef __this_cpu_add_return_4
662# define __this_cpu_add_return_4(pcp, val) __this_cpu_generic_add_return(pcp, val)
663# endif
664# ifndef __this_cpu_add_return_8
665# define __this_cpu_add_return_8(pcp, val) __this_cpu_generic_add_return(pcp, val)
666# endif
667# define __this_cpu_add_return(pcp, val) \
668 __pcpu_size_call_return2(__this_cpu_add_return_, pcp, val)
669#endif
670
671#define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(val))
672#define __this_cpu_inc_return(pcp) __this_cpu_add_return(pcp, 1)
673#define __this_cpu_dec_return(pcp) __this_cpu_add_return(pcp, -1)
674
675#define __this_cpu_generic_xchg(pcp, nval) \
676({ typeof(pcp) ret__; \
677 ret__ = __this_cpu_read(pcp); \
678 __this_cpu_write(pcp, nval); \
679 ret__; \
680})
681
682#ifndef __this_cpu_xchg
683# ifndef __this_cpu_xchg_1
684# define __this_cpu_xchg_1(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
685# endif
686# ifndef __this_cpu_xchg_2
687# define __this_cpu_xchg_2(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
688# endif
689# ifndef __this_cpu_xchg_4
690# define __this_cpu_xchg_4(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
691# endif
692# ifndef __this_cpu_xchg_8
693# define __this_cpu_xchg_8(pcp, nval) __this_cpu_generic_xchg(pcp, nval)
694# endif
695# define __this_cpu_xchg(pcp, nval) \
696 __pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval)
697#endif
698
699#define __this_cpu_generic_cmpxchg(pcp, oval, nval) \
700({ \
701 typeof(pcp) ret__; \
702 ret__ = __this_cpu_read(pcp); \
703 if (ret__ == (oval)) \
704 __this_cpu_write(pcp, nval); \
705 ret__; \
706})
707
708#ifndef __this_cpu_cmpxchg
709# ifndef __this_cpu_cmpxchg_1
710# define __this_cpu_cmpxchg_1(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
711# endif
712# ifndef __this_cpu_cmpxchg_2
713# define __this_cpu_cmpxchg_2(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
714# endif
715# ifndef __this_cpu_cmpxchg_4
716# define __this_cpu_cmpxchg_4(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
717# endif
718# ifndef __this_cpu_cmpxchg_8
719# define __this_cpu_cmpxchg_8(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
720# endif
721# define __this_cpu_cmpxchg(pcp, oval, nval) \
722 __pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval)
723#endif
724
725#define __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
726({ \
727 int __ret = 0; \
728 if (__this_cpu_read(pcp1) == (oval1) && \
729 __this_cpu_read(pcp2) == (oval2)) { \
730 __this_cpu_write(pcp1, (nval1)); \
731 __this_cpu_write(pcp2, (nval2)); \
732 __ret = 1; \
733 } \
734 (__ret); \
735})
736
737#ifndef __this_cpu_cmpxchg_double
738# ifndef __this_cpu_cmpxchg_double_1
739# define __this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \
740 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
741# endif
742# ifndef __this_cpu_cmpxchg_double_2
743# define __this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \
744 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
745# endif
746# ifndef __this_cpu_cmpxchg_double_4
747# define __this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \
748 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
749# endif
750# ifndef __this_cpu_cmpxchg_double_8
751# define __this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \
752 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2)
753# endif
754# define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
755 __pcpu_double_call_return_bool(__this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2))
756#endif
757
758#endif /* __LINUX_PERCPU_H */