Loading...
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_PERCPU_H
3#define _ASM_X86_PERCPU_H
4
5#ifdef CONFIG_X86_64
6#define __percpu_seg gs
7#define __percpu_mov_op movq
8#else
9#define __percpu_seg fs
10#define __percpu_mov_op movl
11#endif
12
13#ifdef __ASSEMBLY__
14
15/*
16 * PER_CPU finds an address of a per-cpu variable.
17 *
18 * Args:
19 * var - variable name
20 * reg - 32bit register
21 *
22 * The resulting address is stored in the "reg" argument.
23 *
24 * Example:
25 * PER_CPU(cpu_gdt_descr, %ebx)
26 */
27#ifdef CONFIG_SMP
28#define PER_CPU(var, reg) \
29 __percpu_mov_op %__percpu_seg:this_cpu_off, reg; \
30 lea var(reg), reg
31#define PER_CPU_VAR(var) %__percpu_seg:var
32#else /* ! SMP */
33#define PER_CPU(var, reg) __percpu_mov_op $var, reg
34#define PER_CPU_VAR(var) var
35#endif /* SMP */
36
37#ifdef CONFIG_X86_64_SMP
38#define INIT_PER_CPU_VAR(var) init_per_cpu__##var
39#else
40#define INIT_PER_CPU_VAR(var) var
41#endif
42
43#else /* ...!ASSEMBLY */
44
45#include <linux/kernel.h>
46#include <linux/stringify.h>
47
48#ifdef CONFIG_SMP
49#define __percpu_prefix "%%"__stringify(__percpu_seg)":"
50#define __my_cpu_offset this_cpu_read(this_cpu_off)
51
52/*
53 * Compared to the generic __my_cpu_offset version, the following
54 * saves one instruction and avoids clobbering a temp register.
55 */
56#define arch_raw_cpu_ptr(ptr) \
57({ \
58 unsigned long tcp_ptr__; \
59 asm volatile("add " __percpu_arg(1) ", %0" \
60 : "=r" (tcp_ptr__) \
61 : "m" (this_cpu_off), "0" (ptr)); \
62 (typeof(*(ptr)) __kernel __force *)tcp_ptr__; \
63})
64#else
65#define __percpu_prefix ""
66#endif
67
68#define __percpu_arg(x) __percpu_prefix "%" #x
69
70/*
71 * Initialized pointers to per-cpu variables needed for the boot
72 * processor need to use these macros to get the proper address
73 * offset from __per_cpu_load on SMP.
74 *
75 * There also must be an entry in vmlinux_64.lds.S
76 */
77#define DECLARE_INIT_PER_CPU(var) \
78 extern typeof(var) init_per_cpu_var(var)
79
80#ifdef CONFIG_X86_64_SMP
81#define init_per_cpu_var(var) init_per_cpu__##var
82#else
83#define init_per_cpu_var(var) var
84#endif
85
86/* For arch-specific code, we can use direct single-insn ops (they
87 * don't give an lvalue though). */
88extern void __bad_percpu_size(void);
89
90#define percpu_to_op(op, var, val) \
91do { \
92 typedef typeof(var) pto_T__; \
93 if (0) { \
94 pto_T__ pto_tmp__; \
95 pto_tmp__ = (val); \
96 (void)pto_tmp__; \
97 } \
98 switch (sizeof(var)) { \
99 case 1: \
100 asm(op "b %1,"__percpu_arg(0) \
101 : "+m" (var) \
102 : "qi" ((pto_T__)(val))); \
103 break; \
104 case 2: \
105 asm(op "w %1,"__percpu_arg(0) \
106 : "+m" (var) \
107 : "ri" ((pto_T__)(val))); \
108 break; \
109 case 4: \
110 asm(op "l %1,"__percpu_arg(0) \
111 : "+m" (var) \
112 : "ri" ((pto_T__)(val))); \
113 break; \
114 case 8: \
115 asm(op "q %1,"__percpu_arg(0) \
116 : "+m" (var) \
117 : "re" ((pto_T__)(val))); \
118 break; \
119 default: __bad_percpu_size(); \
120 } \
121} while (0)
122
123/*
124 * Generate a percpu add to memory instruction and optimize code
125 * if one is added or subtracted.
126 */
127#define percpu_add_op(var, val) \
128do { \
129 typedef typeof(var) pao_T__; \
130 const int pao_ID__ = (__builtin_constant_p(val) && \
131 ((val) == 1 || (val) == -1)) ? \
132 (int)(val) : 0; \
133 if (0) { \
134 pao_T__ pao_tmp__; \
135 pao_tmp__ = (val); \
136 (void)pao_tmp__; \
137 } \
138 switch (sizeof(var)) { \
139 case 1: \
140 if (pao_ID__ == 1) \
141 asm("incb "__percpu_arg(0) : "+m" (var)); \
142 else if (pao_ID__ == -1) \
143 asm("decb "__percpu_arg(0) : "+m" (var)); \
144 else \
145 asm("addb %1, "__percpu_arg(0) \
146 : "+m" (var) \
147 : "qi" ((pao_T__)(val))); \
148 break; \
149 case 2: \
150 if (pao_ID__ == 1) \
151 asm("incw "__percpu_arg(0) : "+m" (var)); \
152 else if (pao_ID__ == -1) \
153 asm("decw "__percpu_arg(0) : "+m" (var)); \
154 else \
155 asm("addw %1, "__percpu_arg(0) \
156 : "+m" (var) \
157 : "ri" ((pao_T__)(val))); \
158 break; \
159 case 4: \
160 if (pao_ID__ == 1) \
161 asm("incl "__percpu_arg(0) : "+m" (var)); \
162 else if (pao_ID__ == -1) \
163 asm("decl "__percpu_arg(0) : "+m" (var)); \
164 else \
165 asm("addl %1, "__percpu_arg(0) \
166 : "+m" (var) \
167 : "ri" ((pao_T__)(val))); \
168 break; \
169 case 8: \
170 if (pao_ID__ == 1) \
171 asm("incq "__percpu_arg(0) : "+m" (var)); \
172 else if (pao_ID__ == -1) \
173 asm("decq "__percpu_arg(0) : "+m" (var)); \
174 else \
175 asm("addq %1, "__percpu_arg(0) \
176 : "+m" (var) \
177 : "re" ((pao_T__)(val))); \
178 break; \
179 default: __bad_percpu_size(); \
180 } \
181} while (0)
182
183#define percpu_from_op(op, var) \
184({ \
185 typeof(var) pfo_ret__; \
186 switch (sizeof(var)) { \
187 case 1: \
188 asm(op "b "__percpu_arg(1)",%0" \
189 : "=q" (pfo_ret__) \
190 : "m" (var)); \
191 break; \
192 case 2: \
193 asm(op "w "__percpu_arg(1)",%0" \
194 : "=r" (pfo_ret__) \
195 : "m" (var)); \
196 break; \
197 case 4: \
198 asm(op "l "__percpu_arg(1)",%0" \
199 : "=r" (pfo_ret__) \
200 : "m" (var)); \
201 break; \
202 case 8: \
203 asm(op "q "__percpu_arg(1)",%0" \
204 : "=r" (pfo_ret__) \
205 : "m" (var)); \
206 break; \
207 default: __bad_percpu_size(); \
208 } \
209 pfo_ret__; \
210})
211
212#define percpu_stable_op(op, var) \
213({ \
214 typeof(var) pfo_ret__; \
215 switch (sizeof(var)) { \
216 case 1: \
217 asm(op "b "__percpu_arg(P1)",%0" \
218 : "=q" (pfo_ret__) \
219 : "p" (&(var))); \
220 break; \
221 case 2: \
222 asm(op "w "__percpu_arg(P1)",%0" \
223 : "=r" (pfo_ret__) \
224 : "p" (&(var))); \
225 break; \
226 case 4: \
227 asm(op "l "__percpu_arg(P1)",%0" \
228 : "=r" (pfo_ret__) \
229 : "p" (&(var))); \
230 break; \
231 case 8: \
232 asm(op "q "__percpu_arg(P1)",%0" \
233 : "=r" (pfo_ret__) \
234 : "p" (&(var))); \
235 break; \
236 default: __bad_percpu_size(); \
237 } \
238 pfo_ret__; \
239})
240
241#define percpu_unary_op(op, var) \
242({ \
243 switch (sizeof(var)) { \
244 case 1: \
245 asm(op "b "__percpu_arg(0) \
246 : "+m" (var)); \
247 break; \
248 case 2: \
249 asm(op "w "__percpu_arg(0) \
250 : "+m" (var)); \
251 break; \
252 case 4: \
253 asm(op "l "__percpu_arg(0) \
254 : "+m" (var)); \
255 break; \
256 case 8: \
257 asm(op "q "__percpu_arg(0) \
258 : "+m" (var)); \
259 break; \
260 default: __bad_percpu_size(); \
261 } \
262})
263
264/*
265 * Add return operation
266 */
267#define percpu_add_return_op(var, val) \
268({ \
269 typeof(var) paro_ret__ = val; \
270 switch (sizeof(var)) { \
271 case 1: \
272 asm("xaddb %0, "__percpu_arg(1) \
273 : "+q" (paro_ret__), "+m" (var) \
274 : : "memory"); \
275 break; \
276 case 2: \
277 asm("xaddw %0, "__percpu_arg(1) \
278 : "+r" (paro_ret__), "+m" (var) \
279 : : "memory"); \
280 break; \
281 case 4: \
282 asm("xaddl %0, "__percpu_arg(1) \
283 : "+r" (paro_ret__), "+m" (var) \
284 : : "memory"); \
285 break; \
286 case 8: \
287 asm("xaddq %0, "__percpu_arg(1) \
288 : "+re" (paro_ret__), "+m" (var) \
289 : : "memory"); \
290 break; \
291 default: __bad_percpu_size(); \
292 } \
293 paro_ret__ += val; \
294 paro_ret__; \
295})
296
297/*
298 * xchg is implemented using cmpxchg without a lock prefix. xchg is
299 * expensive due to the implied lock prefix. The processor cannot prefetch
300 * cachelines if xchg is used.
301 */
302#define percpu_xchg_op(var, nval) \
303({ \
304 typeof(var) pxo_ret__; \
305 typeof(var) pxo_new__ = (nval); \
306 switch (sizeof(var)) { \
307 case 1: \
308 asm("\n\tmov "__percpu_arg(1)",%%al" \
309 "\n1:\tcmpxchgb %2, "__percpu_arg(1) \
310 "\n\tjnz 1b" \
311 : "=&a" (pxo_ret__), "+m" (var) \
312 : "q" (pxo_new__) \
313 : "memory"); \
314 break; \
315 case 2: \
316 asm("\n\tmov "__percpu_arg(1)",%%ax" \
317 "\n1:\tcmpxchgw %2, "__percpu_arg(1) \
318 "\n\tjnz 1b" \
319 : "=&a" (pxo_ret__), "+m" (var) \
320 : "r" (pxo_new__) \
321 : "memory"); \
322 break; \
323 case 4: \
324 asm("\n\tmov "__percpu_arg(1)",%%eax" \
325 "\n1:\tcmpxchgl %2, "__percpu_arg(1) \
326 "\n\tjnz 1b" \
327 : "=&a" (pxo_ret__), "+m" (var) \
328 : "r" (pxo_new__) \
329 : "memory"); \
330 break; \
331 case 8: \
332 asm("\n\tmov "__percpu_arg(1)",%%rax" \
333 "\n1:\tcmpxchgq %2, "__percpu_arg(1) \
334 "\n\tjnz 1b" \
335 : "=&a" (pxo_ret__), "+m" (var) \
336 : "r" (pxo_new__) \
337 : "memory"); \
338 break; \
339 default: __bad_percpu_size(); \
340 } \
341 pxo_ret__; \
342})
343
344/*
345 * cmpxchg has no such implied lock semantics as a result it is much
346 * more efficient for cpu local operations.
347 */
348#define percpu_cmpxchg_op(var, oval, nval) \
349({ \
350 typeof(var) pco_ret__; \
351 typeof(var) pco_old__ = (oval); \
352 typeof(var) pco_new__ = (nval); \
353 switch (sizeof(var)) { \
354 case 1: \
355 asm("cmpxchgb %2, "__percpu_arg(1) \
356 : "=a" (pco_ret__), "+m" (var) \
357 : "q" (pco_new__), "0" (pco_old__) \
358 : "memory"); \
359 break; \
360 case 2: \
361 asm("cmpxchgw %2, "__percpu_arg(1) \
362 : "=a" (pco_ret__), "+m" (var) \
363 : "r" (pco_new__), "0" (pco_old__) \
364 : "memory"); \
365 break; \
366 case 4: \
367 asm("cmpxchgl %2, "__percpu_arg(1) \
368 : "=a" (pco_ret__), "+m" (var) \
369 : "r" (pco_new__), "0" (pco_old__) \
370 : "memory"); \
371 break; \
372 case 8: \
373 asm("cmpxchgq %2, "__percpu_arg(1) \
374 : "=a" (pco_ret__), "+m" (var) \
375 : "r" (pco_new__), "0" (pco_old__) \
376 : "memory"); \
377 break; \
378 default: __bad_percpu_size(); \
379 } \
380 pco_ret__; \
381})
382
383/*
384 * this_cpu_read() makes gcc load the percpu variable every time it is
385 * accessed while this_cpu_read_stable() allows the value to be cached.
386 * this_cpu_read_stable() is more efficient and can be used if its value
387 * is guaranteed to be valid across cpus. The current users include
388 * get_current() and get_thread_info() both of which are actually
389 * per-thread variables implemented as per-cpu variables and thus
390 * stable for the duration of the respective task.
391 */
392#define this_cpu_read_stable(var) percpu_stable_op("mov", var)
393
394#define raw_cpu_read_1(pcp) percpu_from_op("mov", pcp)
395#define raw_cpu_read_2(pcp) percpu_from_op("mov", pcp)
396#define raw_cpu_read_4(pcp) percpu_from_op("mov", pcp)
397
398#define raw_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val)
399#define raw_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val)
400#define raw_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val)
401#define raw_cpu_add_1(pcp, val) percpu_add_op((pcp), val)
402#define raw_cpu_add_2(pcp, val) percpu_add_op((pcp), val)
403#define raw_cpu_add_4(pcp, val) percpu_add_op((pcp), val)
404#define raw_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
405#define raw_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
406#define raw_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
407#define raw_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
408#define raw_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
409#define raw_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
410#define raw_cpu_xchg_1(pcp, val) percpu_xchg_op(pcp, val)
411#define raw_cpu_xchg_2(pcp, val) percpu_xchg_op(pcp, val)
412#define raw_cpu_xchg_4(pcp, val) percpu_xchg_op(pcp, val)
413
414#define this_cpu_read_1(pcp) percpu_from_op("mov", pcp)
415#define this_cpu_read_2(pcp) percpu_from_op("mov", pcp)
416#define this_cpu_read_4(pcp) percpu_from_op("mov", pcp)
417#define this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val)
418#define this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val)
419#define this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val)
420#define this_cpu_add_1(pcp, val) percpu_add_op((pcp), val)
421#define this_cpu_add_2(pcp, val) percpu_add_op((pcp), val)
422#define this_cpu_add_4(pcp, val) percpu_add_op((pcp), val)
423#define this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val)
424#define this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val)
425#define this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val)
426#define this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val)
427#define this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val)
428#define this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val)
429#define this_cpu_xchg_1(pcp, nval) percpu_xchg_op(pcp, nval)
430#define this_cpu_xchg_2(pcp, nval) percpu_xchg_op(pcp, nval)
431#define this_cpu_xchg_4(pcp, nval) percpu_xchg_op(pcp, nval)
432
433#define raw_cpu_add_return_1(pcp, val) percpu_add_return_op(pcp, val)
434#define raw_cpu_add_return_2(pcp, val) percpu_add_return_op(pcp, val)
435#define raw_cpu_add_return_4(pcp, val) percpu_add_return_op(pcp, val)
436#define raw_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
437#define raw_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
438#define raw_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
439
440#define this_cpu_add_return_1(pcp, val) percpu_add_return_op(pcp, val)
441#define this_cpu_add_return_2(pcp, val) percpu_add_return_op(pcp, val)
442#define this_cpu_add_return_4(pcp, val) percpu_add_return_op(pcp, val)
443#define this_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
444#define this_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
445#define this_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
446
447#ifdef CONFIG_X86_CMPXCHG64
448#define percpu_cmpxchg8b_double(pcp1, pcp2, o1, o2, n1, n2) \
449({ \
450 bool __ret; \
451 typeof(pcp1) __o1 = (o1), __n1 = (n1); \
452 typeof(pcp2) __o2 = (o2), __n2 = (n2); \
453 asm volatile("cmpxchg8b "__percpu_arg(1)"\n\tsetz %0\n\t" \
454 : "=a" (__ret), "+m" (pcp1), "+m" (pcp2), "+d" (__o2) \
455 : "b" (__n1), "c" (__n2), "a" (__o1)); \
456 __ret; \
457})
458
459#define raw_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double
460#define this_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double
461#endif /* CONFIG_X86_CMPXCHG64 */
462
463/*
464 * Per cpu atomic 64 bit operations are only available under 64 bit.
465 * 32 bit must fall back to generic operations.
466 */
467#ifdef CONFIG_X86_64
468#define raw_cpu_read_8(pcp) percpu_from_op("mov", pcp)
469#define raw_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val)
470#define raw_cpu_add_8(pcp, val) percpu_add_op((pcp), val)
471#define raw_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
472#define raw_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
473#define raw_cpu_add_return_8(pcp, val) percpu_add_return_op(pcp, val)
474#define raw_cpu_xchg_8(pcp, nval) percpu_xchg_op(pcp, nval)
475#define raw_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
476
477#define this_cpu_read_8(pcp) percpu_from_op("mov", pcp)
478#define this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val)
479#define this_cpu_add_8(pcp, val) percpu_add_op((pcp), val)
480#define this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val)
481#define this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val)
482#define this_cpu_add_return_8(pcp, val) percpu_add_return_op(pcp, val)
483#define this_cpu_xchg_8(pcp, nval) percpu_xchg_op(pcp, nval)
484#define this_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval)
485
486/*
487 * Pretty complex macro to generate cmpxchg16 instruction. The instruction
488 * is not supported on early AMD64 processors so we must be able to emulate
489 * it in software. The address used in the cmpxchg16 instruction must be
490 * aligned to a 16 byte boundary.
491 */
492#define percpu_cmpxchg16b_double(pcp1, pcp2, o1, o2, n1, n2) \
493({ \
494 bool __ret; \
495 typeof(pcp1) __o1 = (o1), __n1 = (n1); \
496 typeof(pcp2) __o2 = (o2), __n2 = (n2); \
497 alternative_io("leaq %P1,%%rsi\n\tcall this_cpu_cmpxchg16b_emu\n\t", \
498 "cmpxchg16b " __percpu_arg(1) "\n\tsetz %0\n\t", \
499 X86_FEATURE_CX16, \
500 ASM_OUTPUT2("=a" (__ret), "+m" (pcp1), \
501 "+m" (pcp2), "+d" (__o2)), \
502 "b" (__n1), "c" (__n2), "a" (__o1) : "rsi"); \
503 __ret; \
504})
505
506#define raw_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double
507#define this_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double
508
509#endif
510
511static __always_inline bool x86_this_cpu_constant_test_bit(unsigned int nr,
512 const unsigned long __percpu *addr)
513{
514 unsigned long __percpu *a =
515 (unsigned long __percpu *)addr + nr / BITS_PER_LONG;
516
517#ifdef CONFIG_X86_64
518 return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_8(*a)) != 0;
519#else
520 return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_4(*a)) != 0;
521#endif
522}
523
524static inline bool x86_this_cpu_variable_test_bit(int nr,
525 const unsigned long __percpu *addr)
526{
527 bool oldbit;
528
529 asm volatile("btl "__percpu_arg(2)",%1"
530 CC_SET(c)
531 : CC_OUT(c) (oldbit)
532 : "m" (*(unsigned long __percpu *)addr), "Ir" (nr));
533
534 return oldbit;
535}
536
537#define x86_this_cpu_test_bit(nr, addr) \
538 (__builtin_constant_p((nr)) \
539 ? x86_this_cpu_constant_test_bit((nr), (addr)) \
540 : x86_this_cpu_variable_test_bit((nr), (addr)))
541
542
543#include <asm-generic/percpu.h>
544
545/* We can use this directly for local CPU (faster). */
546DECLARE_PER_CPU_READ_MOSTLY(unsigned long, this_cpu_off);
547
548#endif /* !__ASSEMBLY__ */
549
550#ifdef CONFIG_SMP
551
552/*
553 * Define the "EARLY_PER_CPU" macros. These are used for some per_cpu
554 * variables that are initialized and accessed before there are per_cpu
555 * areas allocated.
556 */
557
558#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
559 DEFINE_PER_CPU(_type, _name) = _initvalue; \
560 __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
561 { [0 ... NR_CPUS-1] = _initvalue }; \
562 __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
563
564#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \
565 DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue; \
566 __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
567 { [0 ... NR_CPUS-1] = _initvalue }; \
568 __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
569
570#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
571 EXPORT_PER_CPU_SYMBOL(_name)
572
573#define DECLARE_EARLY_PER_CPU(_type, _name) \
574 DECLARE_PER_CPU(_type, _name); \
575 extern __typeof__(_type) *_name##_early_ptr; \
576 extern __typeof__(_type) _name##_early_map[]
577
578#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \
579 DECLARE_PER_CPU_READ_MOSTLY(_type, _name); \
580 extern __typeof__(_type) *_name##_early_ptr; \
581 extern __typeof__(_type) _name##_early_map[]
582
583#define early_per_cpu_ptr(_name) (_name##_early_ptr)
584#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
585#define early_per_cpu(_name, _cpu) \
586 *(early_per_cpu_ptr(_name) ? \
587 &early_per_cpu_ptr(_name)[_cpu] : \
588 &per_cpu(_name, _cpu))
589
590#else /* !CONFIG_SMP */
591#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
592 DEFINE_PER_CPU(_type, _name) = _initvalue
593
594#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \
595 DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue
596
597#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
598 EXPORT_PER_CPU_SYMBOL(_name)
599
600#define DECLARE_EARLY_PER_CPU(_type, _name) \
601 DECLARE_PER_CPU(_type, _name)
602
603#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \
604 DECLARE_PER_CPU_READ_MOSTLY(_type, _name)
605
606#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
607#define early_per_cpu_ptr(_name) NULL
608/* no early_per_cpu_map() */
609
610#endif /* !CONFIG_SMP */
611
612#endif /* _ASM_X86_PERCPU_H */
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_PERCPU_H
3#define _ASM_X86_PERCPU_H
4
5#ifdef CONFIG_X86_64
6#define __percpu_seg gs
7#else
8#define __percpu_seg fs
9#endif
10
11#ifdef __ASSEMBLY__
12
13#ifdef CONFIG_SMP
14#define PER_CPU_VAR(var) %__percpu_seg:var
15#else /* ! SMP */
16#define PER_CPU_VAR(var) var
17#endif /* SMP */
18
19#ifdef CONFIG_X86_64_SMP
20#define INIT_PER_CPU_VAR(var) init_per_cpu__##var
21#else
22#define INIT_PER_CPU_VAR(var) var
23#endif
24
25#else /* ...!ASSEMBLY */
26
27#include <linux/kernel.h>
28#include <linux/stringify.h>
29
30#ifdef CONFIG_SMP
31#define __percpu_prefix "%%"__stringify(__percpu_seg)":"
32#define __my_cpu_offset this_cpu_read(this_cpu_off)
33
34/*
35 * Compared to the generic __my_cpu_offset version, the following
36 * saves one instruction and avoids clobbering a temp register.
37 */
38#define arch_raw_cpu_ptr(ptr) \
39({ \
40 unsigned long tcp_ptr__; \
41 asm ("add " __percpu_arg(1) ", %0" \
42 : "=r" (tcp_ptr__) \
43 : "m" (this_cpu_off), "0" (ptr)); \
44 (typeof(*(ptr)) __kernel __force *)tcp_ptr__; \
45})
46#else
47#define __percpu_prefix ""
48#endif
49
50#define __percpu_arg(x) __percpu_prefix "%" #x
51
52/*
53 * Initialized pointers to per-cpu variables needed for the boot
54 * processor need to use these macros to get the proper address
55 * offset from __per_cpu_load on SMP.
56 *
57 * There also must be an entry in vmlinux_64.lds.S
58 */
59#define DECLARE_INIT_PER_CPU(var) \
60 extern typeof(var) init_per_cpu_var(var)
61
62#ifdef CONFIG_X86_64_SMP
63#define init_per_cpu_var(var) init_per_cpu__##var
64#else
65#define init_per_cpu_var(var) var
66#endif
67
68/* For arch-specific code, we can use direct single-insn ops (they
69 * don't give an lvalue though). */
70
71#define __pcpu_type_1 u8
72#define __pcpu_type_2 u16
73#define __pcpu_type_4 u32
74#define __pcpu_type_8 u64
75
76#define __pcpu_cast_1(val) ((u8)(((unsigned long) val) & 0xff))
77#define __pcpu_cast_2(val) ((u16)(((unsigned long) val) & 0xffff))
78#define __pcpu_cast_4(val) ((u32)(((unsigned long) val) & 0xffffffff))
79#define __pcpu_cast_8(val) ((u64)(val))
80
81#define __pcpu_op1_1(op, dst) op "b " dst
82#define __pcpu_op1_2(op, dst) op "w " dst
83#define __pcpu_op1_4(op, dst) op "l " dst
84#define __pcpu_op1_8(op, dst) op "q " dst
85
86#define __pcpu_op2_1(op, src, dst) op "b " src ", " dst
87#define __pcpu_op2_2(op, src, dst) op "w " src ", " dst
88#define __pcpu_op2_4(op, src, dst) op "l " src ", " dst
89#define __pcpu_op2_8(op, src, dst) op "q " src ", " dst
90
91#define __pcpu_reg_1(mod, x) mod "q" (x)
92#define __pcpu_reg_2(mod, x) mod "r" (x)
93#define __pcpu_reg_4(mod, x) mod "r" (x)
94#define __pcpu_reg_8(mod, x) mod "r" (x)
95
96#define __pcpu_reg_imm_1(x) "qi" (x)
97#define __pcpu_reg_imm_2(x) "ri" (x)
98#define __pcpu_reg_imm_4(x) "ri" (x)
99#define __pcpu_reg_imm_8(x) "re" (x)
100
101#define percpu_to_op(size, qual, op, _var, _val) \
102do { \
103 __pcpu_type_##size pto_val__ = __pcpu_cast_##size(_val); \
104 if (0) { \
105 typeof(_var) pto_tmp__; \
106 pto_tmp__ = (_val); \
107 (void)pto_tmp__; \
108 } \
109 asm qual(__pcpu_op2_##size(op, "%[val]", __percpu_arg([var])) \
110 : [var] "+m" (_var) \
111 : [val] __pcpu_reg_imm_##size(pto_val__)); \
112} while (0)
113
114#define percpu_unary_op(size, qual, op, _var) \
115({ \
116 asm qual (__pcpu_op1_##size(op, __percpu_arg([var])) \
117 : [var] "+m" (_var)); \
118})
119
120/*
121 * Generate a percpu add to memory instruction and optimize code
122 * if one is added or subtracted.
123 */
124#define percpu_add_op(size, qual, var, val) \
125do { \
126 const int pao_ID__ = (__builtin_constant_p(val) && \
127 ((val) == 1 || (val) == -1)) ? \
128 (int)(val) : 0; \
129 if (0) { \
130 typeof(var) pao_tmp__; \
131 pao_tmp__ = (val); \
132 (void)pao_tmp__; \
133 } \
134 if (pao_ID__ == 1) \
135 percpu_unary_op(size, qual, "inc", var); \
136 else if (pao_ID__ == -1) \
137 percpu_unary_op(size, qual, "dec", var); \
138 else \
139 percpu_to_op(size, qual, "add", var, val); \
140} while (0)
141
142#define percpu_from_op(size, qual, op, _var) \
143({ \
144 __pcpu_type_##size pfo_val__; \
145 asm qual (__pcpu_op2_##size(op, __percpu_arg([var]), "%[val]") \
146 : [val] __pcpu_reg_##size("=", pfo_val__) \
147 : [var] "m" (_var)); \
148 (typeof(_var))(unsigned long) pfo_val__; \
149})
150
151#define percpu_stable_op(size, op, _var) \
152({ \
153 __pcpu_type_##size pfo_val__; \
154 asm(__pcpu_op2_##size(op, __percpu_arg(P[var]), "%[val]") \
155 : [val] __pcpu_reg_##size("=", pfo_val__) \
156 : [var] "p" (&(_var))); \
157 (typeof(_var))(unsigned long) pfo_val__; \
158})
159
160/*
161 * Add return operation
162 */
163#define percpu_add_return_op(size, qual, _var, _val) \
164({ \
165 __pcpu_type_##size paro_tmp__ = __pcpu_cast_##size(_val); \
166 asm qual (__pcpu_op2_##size("xadd", "%[tmp]", \
167 __percpu_arg([var])) \
168 : [tmp] __pcpu_reg_##size("+", paro_tmp__), \
169 [var] "+m" (_var) \
170 : : "memory"); \
171 (typeof(_var))(unsigned long) (paro_tmp__ + _val); \
172})
173
174/*
175 * xchg is implemented using cmpxchg without a lock prefix. xchg is
176 * expensive due to the implied lock prefix. The processor cannot prefetch
177 * cachelines if xchg is used.
178 */
179#define percpu_xchg_op(size, qual, _var, _nval) \
180({ \
181 __pcpu_type_##size pxo_old__; \
182 __pcpu_type_##size pxo_new__ = __pcpu_cast_##size(_nval); \
183 asm qual (__pcpu_op2_##size("mov", __percpu_arg([var]), \
184 "%[oval]") \
185 "\n1:\t" \
186 __pcpu_op2_##size("cmpxchg", "%[nval]", \
187 __percpu_arg([var])) \
188 "\n\tjnz 1b" \
189 : [oval] "=&a" (pxo_old__), \
190 [var] "+m" (_var) \
191 : [nval] __pcpu_reg_##size(, pxo_new__) \
192 : "memory"); \
193 (typeof(_var))(unsigned long) pxo_old__; \
194})
195
196/*
197 * cmpxchg has no such implied lock semantics as a result it is much
198 * more efficient for cpu local operations.
199 */
200#define percpu_cmpxchg_op(size, qual, _var, _oval, _nval) \
201({ \
202 __pcpu_type_##size pco_old__ = __pcpu_cast_##size(_oval); \
203 __pcpu_type_##size pco_new__ = __pcpu_cast_##size(_nval); \
204 asm qual (__pcpu_op2_##size("cmpxchg", "%[nval]", \
205 __percpu_arg([var])) \
206 : [oval] "+a" (pco_old__), \
207 [var] "+m" (_var) \
208 : [nval] __pcpu_reg_##size(, pco_new__) \
209 : "memory"); \
210 (typeof(_var))(unsigned long) pco_old__; \
211})
212
213/*
214 * this_cpu_read() makes gcc load the percpu variable every time it is
215 * accessed while this_cpu_read_stable() allows the value to be cached.
216 * this_cpu_read_stable() is more efficient and can be used if its value
217 * is guaranteed to be valid across cpus. The current users include
218 * get_current() and get_thread_info() both of which are actually
219 * per-thread variables implemented as per-cpu variables and thus
220 * stable for the duration of the respective task.
221 */
222#define this_cpu_read_stable_1(pcp) percpu_stable_op(1, "mov", pcp)
223#define this_cpu_read_stable_2(pcp) percpu_stable_op(2, "mov", pcp)
224#define this_cpu_read_stable_4(pcp) percpu_stable_op(4, "mov", pcp)
225#define this_cpu_read_stable_8(pcp) percpu_stable_op(8, "mov", pcp)
226#define this_cpu_read_stable(pcp) __pcpu_size_call_return(this_cpu_read_stable_, pcp)
227
228#define raw_cpu_read_1(pcp) percpu_from_op(1, , "mov", pcp)
229#define raw_cpu_read_2(pcp) percpu_from_op(2, , "mov", pcp)
230#define raw_cpu_read_4(pcp) percpu_from_op(4, , "mov", pcp)
231
232#define raw_cpu_write_1(pcp, val) percpu_to_op(1, , "mov", (pcp), val)
233#define raw_cpu_write_2(pcp, val) percpu_to_op(2, , "mov", (pcp), val)
234#define raw_cpu_write_4(pcp, val) percpu_to_op(4, , "mov", (pcp), val)
235#define raw_cpu_add_1(pcp, val) percpu_add_op(1, , (pcp), val)
236#define raw_cpu_add_2(pcp, val) percpu_add_op(2, , (pcp), val)
237#define raw_cpu_add_4(pcp, val) percpu_add_op(4, , (pcp), val)
238#define raw_cpu_and_1(pcp, val) percpu_to_op(1, , "and", (pcp), val)
239#define raw_cpu_and_2(pcp, val) percpu_to_op(2, , "and", (pcp), val)
240#define raw_cpu_and_4(pcp, val) percpu_to_op(4, , "and", (pcp), val)
241#define raw_cpu_or_1(pcp, val) percpu_to_op(1, , "or", (pcp), val)
242#define raw_cpu_or_2(pcp, val) percpu_to_op(2, , "or", (pcp), val)
243#define raw_cpu_or_4(pcp, val) percpu_to_op(4, , "or", (pcp), val)
244
245/*
246 * raw_cpu_xchg() can use a load-store since it is not required to be
247 * IRQ-safe.
248 */
249#define raw_percpu_xchg_op(var, nval) \
250({ \
251 typeof(var) pxo_ret__ = raw_cpu_read(var); \
252 raw_cpu_write(var, (nval)); \
253 pxo_ret__; \
254})
255
256#define raw_cpu_xchg_1(pcp, val) raw_percpu_xchg_op(pcp, val)
257#define raw_cpu_xchg_2(pcp, val) raw_percpu_xchg_op(pcp, val)
258#define raw_cpu_xchg_4(pcp, val) raw_percpu_xchg_op(pcp, val)
259
260#define this_cpu_read_1(pcp) percpu_from_op(1, volatile, "mov", pcp)
261#define this_cpu_read_2(pcp) percpu_from_op(2, volatile, "mov", pcp)
262#define this_cpu_read_4(pcp) percpu_from_op(4, volatile, "mov", pcp)
263#define this_cpu_write_1(pcp, val) percpu_to_op(1, volatile, "mov", (pcp), val)
264#define this_cpu_write_2(pcp, val) percpu_to_op(2, volatile, "mov", (pcp), val)
265#define this_cpu_write_4(pcp, val) percpu_to_op(4, volatile, "mov", (pcp), val)
266#define this_cpu_add_1(pcp, val) percpu_add_op(1, volatile, (pcp), val)
267#define this_cpu_add_2(pcp, val) percpu_add_op(2, volatile, (pcp), val)
268#define this_cpu_add_4(pcp, val) percpu_add_op(4, volatile, (pcp), val)
269#define this_cpu_and_1(pcp, val) percpu_to_op(1, volatile, "and", (pcp), val)
270#define this_cpu_and_2(pcp, val) percpu_to_op(2, volatile, "and", (pcp), val)
271#define this_cpu_and_4(pcp, val) percpu_to_op(4, volatile, "and", (pcp), val)
272#define this_cpu_or_1(pcp, val) percpu_to_op(1, volatile, "or", (pcp), val)
273#define this_cpu_or_2(pcp, val) percpu_to_op(2, volatile, "or", (pcp), val)
274#define this_cpu_or_4(pcp, val) percpu_to_op(4, volatile, "or", (pcp), val)
275#define this_cpu_xchg_1(pcp, nval) percpu_xchg_op(1, volatile, pcp, nval)
276#define this_cpu_xchg_2(pcp, nval) percpu_xchg_op(2, volatile, pcp, nval)
277#define this_cpu_xchg_4(pcp, nval) percpu_xchg_op(4, volatile, pcp, nval)
278
279#define raw_cpu_add_return_1(pcp, val) percpu_add_return_op(1, , pcp, val)
280#define raw_cpu_add_return_2(pcp, val) percpu_add_return_op(2, , pcp, val)
281#define raw_cpu_add_return_4(pcp, val) percpu_add_return_op(4, , pcp, val)
282#define raw_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(1, , pcp, oval, nval)
283#define raw_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(2, , pcp, oval, nval)
284#define raw_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(4, , pcp, oval, nval)
285
286#define this_cpu_add_return_1(pcp, val) percpu_add_return_op(1, volatile, pcp, val)
287#define this_cpu_add_return_2(pcp, val) percpu_add_return_op(2, volatile, pcp, val)
288#define this_cpu_add_return_4(pcp, val) percpu_add_return_op(4, volatile, pcp, val)
289#define this_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(1, volatile, pcp, oval, nval)
290#define this_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(2, volatile, pcp, oval, nval)
291#define this_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(4, volatile, pcp, oval, nval)
292
293#ifdef CONFIG_X86_CMPXCHG64
294#define percpu_cmpxchg8b_double(pcp1, pcp2, o1, o2, n1, n2) \
295({ \
296 bool __ret; \
297 typeof(pcp1) __o1 = (o1), __n1 = (n1); \
298 typeof(pcp2) __o2 = (o2), __n2 = (n2); \
299 asm volatile("cmpxchg8b "__percpu_arg(1) \
300 CC_SET(z) \
301 : CC_OUT(z) (__ret), "+m" (pcp1), "+m" (pcp2), "+a" (__o1), "+d" (__o2) \
302 : "b" (__n1), "c" (__n2)); \
303 __ret; \
304})
305
306#define raw_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double
307#define this_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double
308#endif /* CONFIG_X86_CMPXCHG64 */
309
310/*
311 * Per cpu atomic 64 bit operations are only available under 64 bit.
312 * 32 bit must fall back to generic operations.
313 */
314#ifdef CONFIG_X86_64
315#define raw_cpu_read_8(pcp) percpu_from_op(8, , "mov", pcp)
316#define raw_cpu_write_8(pcp, val) percpu_to_op(8, , "mov", (pcp), val)
317#define raw_cpu_add_8(pcp, val) percpu_add_op(8, , (pcp), val)
318#define raw_cpu_and_8(pcp, val) percpu_to_op(8, , "and", (pcp), val)
319#define raw_cpu_or_8(pcp, val) percpu_to_op(8, , "or", (pcp), val)
320#define raw_cpu_add_return_8(pcp, val) percpu_add_return_op(8, , pcp, val)
321#define raw_cpu_xchg_8(pcp, nval) raw_percpu_xchg_op(pcp, nval)
322#define raw_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(8, , pcp, oval, nval)
323
324#define this_cpu_read_8(pcp) percpu_from_op(8, volatile, "mov", pcp)
325#define this_cpu_write_8(pcp, val) percpu_to_op(8, volatile, "mov", (pcp), val)
326#define this_cpu_add_8(pcp, val) percpu_add_op(8, volatile, (pcp), val)
327#define this_cpu_and_8(pcp, val) percpu_to_op(8, volatile, "and", (pcp), val)
328#define this_cpu_or_8(pcp, val) percpu_to_op(8, volatile, "or", (pcp), val)
329#define this_cpu_add_return_8(pcp, val) percpu_add_return_op(8, volatile, pcp, val)
330#define this_cpu_xchg_8(pcp, nval) percpu_xchg_op(8, volatile, pcp, nval)
331#define this_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(8, volatile, pcp, oval, nval)
332
333/*
334 * Pretty complex macro to generate cmpxchg16 instruction. The instruction
335 * is not supported on early AMD64 processors so we must be able to emulate
336 * it in software. The address used in the cmpxchg16 instruction must be
337 * aligned to a 16 byte boundary.
338 */
339#define percpu_cmpxchg16b_double(pcp1, pcp2, o1, o2, n1, n2) \
340({ \
341 bool __ret; \
342 typeof(pcp1) __o1 = (o1), __n1 = (n1); \
343 typeof(pcp2) __o2 = (o2), __n2 = (n2); \
344 alternative_io("leaq %P1,%%rsi\n\tcall this_cpu_cmpxchg16b_emu\n\t", \
345 "cmpxchg16b " __percpu_arg(1) "\n\tsetz %0\n\t", \
346 X86_FEATURE_CX16, \
347 ASM_OUTPUT2("=a" (__ret), "+m" (pcp1), \
348 "+m" (pcp2), "+d" (__o2)), \
349 "b" (__n1), "c" (__n2), "a" (__o1) : "rsi"); \
350 __ret; \
351})
352
353#define raw_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double
354#define this_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double
355
356#endif
357
358static __always_inline bool x86_this_cpu_constant_test_bit(unsigned int nr,
359 const unsigned long __percpu *addr)
360{
361 unsigned long __percpu *a =
362 (unsigned long __percpu *)addr + nr / BITS_PER_LONG;
363
364#ifdef CONFIG_X86_64
365 return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_8(*a)) != 0;
366#else
367 return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_4(*a)) != 0;
368#endif
369}
370
371static inline bool x86_this_cpu_variable_test_bit(int nr,
372 const unsigned long __percpu *addr)
373{
374 bool oldbit;
375
376 asm volatile("btl "__percpu_arg(2)",%1"
377 CC_SET(c)
378 : CC_OUT(c) (oldbit)
379 : "m" (*(unsigned long __percpu *)addr), "Ir" (nr));
380
381 return oldbit;
382}
383
384#define x86_this_cpu_test_bit(nr, addr) \
385 (__builtin_constant_p((nr)) \
386 ? x86_this_cpu_constant_test_bit((nr), (addr)) \
387 : x86_this_cpu_variable_test_bit((nr), (addr)))
388
389
390#include <asm-generic/percpu.h>
391
392/* We can use this directly for local CPU (faster). */
393DECLARE_PER_CPU_READ_MOSTLY(unsigned long, this_cpu_off);
394
395#endif /* !__ASSEMBLY__ */
396
397#ifdef CONFIG_SMP
398
399/*
400 * Define the "EARLY_PER_CPU" macros. These are used for some per_cpu
401 * variables that are initialized and accessed before there are per_cpu
402 * areas allocated.
403 */
404
405#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
406 DEFINE_PER_CPU(_type, _name) = _initvalue; \
407 __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
408 { [0 ... NR_CPUS-1] = _initvalue }; \
409 __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
410
411#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \
412 DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue; \
413 __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
414 { [0 ... NR_CPUS-1] = _initvalue }; \
415 __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
416
417#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
418 EXPORT_PER_CPU_SYMBOL(_name)
419
420#define DECLARE_EARLY_PER_CPU(_type, _name) \
421 DECLARE_PER_CPU(_type, _name); \
422 extern __typeof__(_type) *_name##_early_ptr; \
423 extern __typeof__(_type) _name##_early_map[]
424
425#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \
426 DECLARE_PER_CPU_READ_MOSTLY(_type, _name); \
427 extern __typeof__(_type) *_name##_early_ptr; \
428 extern __typeof__(_type) _name##_early_map[]
429
430#define early_per_cpu_ptr(_name) (_name##_early_ptr)
431#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
432#define early_per_cpu(_name, _cpu) \
433 *(early_per_cpu_ptr(_name) ? \
434 &early_per_cpu_ptr(_name)[_cpu] : \
435 &per_cpu(_name, _cpu))
436
437#else /* !CONFIG_SMP */
438#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
439 DEFINE_PER_CPU(_type, _name) = _initvalue
440
441#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \
442 DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue
443
444#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
445 EXPORT_PER_CPU_SYMBOL(_name)
446
447#define DECLARE_EARLY_PER_CPU(_type, _name) \
448 DECLARE_PER_CPU(_type, _name)
449
450#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \
451 DECLARE_PER_CPU_READ_MOSTLY(_type, _name)
452
453#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
454#define early_per_cpu_ptr(_name) NULL
455/* no early_per_cpu_map() */
456
457#endif /* !CONFIG_SMP */
458
459#endif /* _ASM_X86_PERCPU_H */