Linux Audio

Check our new training course

Loading...
v4.10.11
 
  1#ifndef _ASM_X86_PERCPU_H
  2#define _ASM_X86_PERCPU_H
  3
  4#ifdef CONFIG_X86_64
  5#define __percpu_seg		gs
  6#define __percpu_mov_op		movq
  7#else
  8#define __percpu_seg		fs
  9#define __percpu_mov_op		movl
 10#endif
 11
 12#ifdef __ASSEMBLY__
 13
 14/*
 15 * PER_CPU finds an address of a per-cpu variable.
 16 *
 17 * Args:
 18 *    var - variable name
 19 *    reg - 32bit register
 20 *
 21 * The resulting address is stored in the "reg" argument.
 22 *
 23 * Example:
 24 *    PER_CPU(cpu_gdt_descr, %ebx)
 25 */
 26#ifdef CONFIG_SMP
 27#define PER_CPU(var, reg)						\
 28	__percpu_mov_op %__percpu_seg:this_cpu_off, reg;		\
 29	lea var(reg), reg
 30#define PER_CPU_VAR(var)	%__percpu_seg:var
 31#else /* ! SMP */
 32#define PER_CPU(var, reg)	__percpu_mov_op $var, reg
 33#define PER_CPU_VAR(var)	var
 34#endif	/* SMP */
 35
 36#ifdef CONFIG_X86_64_SMP
 37#define INIT_PER_CPU_VAR(var)  init_per_cpu__##var
 38#else
 39#define INIT_PER_CPU_VAR(var)  var
 40#endif
 41
 42#else /* ...!ASSEMBLY */
 43
 44#include <linux/kernel.h>
 45#include <linux/stringify.h>
 46
 47#ifdef CONFIG_SMP
 48#define __percpu_prefix		"%%"__stringify(__percpu_seg)":"
 49#define __my_cpu_offset		this_cpu_read(this_cpu_off)
 50
 51/*
 52 * Compared to the generic __my_cpu_offset version, the following
 53 * saves one instruction and avoids clobbering a temp register.
 54 */
 55#define arch_raw_cpu_ptr(ptr)				\
 56({							\
 57	unsigned long tcp_ptr__;			\
 58	asm volatile("add " __percpu_arg(1) ", %0"	\
 59		     : "=r" (tcp_ptr__)			\
 60		     : "m" (this_cpu_off), "0" (ptr));	\
 61	(typeof(*(ptr)) __kernel __force *)tcp_ptr__;	\
 62})
 63#else
 64#define __percpu_prefix		""
 65#endif
 66
 67#define __percpu_arg(x)		__percpu_prefix "%" #x
 68
 69/*
 70 * Initialized pointers to per-cpu variables needed for the boot
 71 * processor need to use these macros to get the proper address
 72 * offset from __per_cpu_load on SMP.
 73 *
 74 * There also must be an entry in vmlinux_64.lds.S
 75 */
 76#define DECLARE_INIT_PER_CPU(var) \
 77       extern typeof(var) init_per_cpu_var(var)
 78
 79#ifdef CONFIG_X86_64_SMP
 80#define init_per_cpu_var(var)  init_per_cpu__##var
 81#else
 82#define init_per_cpu_var(var)  var
 83#endif
 84
 85/* For arch-specific code, we can use direct single-insn ops (they
 86 * don't give an lvalue though). */
 87extern void __bad_percpu_size(void);
 88
 89#define percpu_to_op(op, var, val)			\
 90do {							\
 91	typedef typeof(var) pto_T__;			\
 92	if (0) {					\
 93		pto_T__ pto_tmp__;			\
 94		pto_tmp__ = (val);			\
 95		(void)pto_tmp__;			\
 96	}						\
 97	switch (sizeof(var)) {				\
 98	case 1:						\
 99		asm(op "b %1,"__percpu_arg(0)		\
100		    : "+m" (var)			\
101		    : "qi" ((pto_T__)(val)));		\
102		break;					\
103	case 2:						\
104		asm(op "w %1,"__percpu_arg(0)		\
105		    : "+m" (var)			\
106		    : "ri" ((pto_T__)(val)));		\
107		break;					\
108	case 4:						\
109		asm(op "l %1,"__percpu_arg(0)		\
110		    : "+m" (var)			\
111		    : "ri" ((pto_T__)(val)));		\
112		break;					\
113	case 8:						\
114		asm(op "q %1,"__percpu_arg(0)		\
115		    : "+m" (var)			\
116		    : "re" ((pto_T__)(val)));		\
117		break;					\
118	default: __bad_percpu_size();			\
119	}						\
 
 
 
 
 
 
 
 
 
 
120} while (0)
121
 
 
 
 
 
 
122/*
123 * Generate a percpu add to memory instruction and optimize code
124 * if one is added or subtracted.
125 */
126#define percpu_add_op(var, val)						\
127do {									\
128	typedef typeof(var) pao_T__;					\
129	const int pao_ID__ = (__builtin_constant_p(val) &&		\
130			      ((val) == 1 || (val) == -1)) ?		\
131				(int)(val) : 0;				\
132	if (0) {							\
133		pao_T__ pao_tmp__;					\
134		pao_tmp__ = (val);					\
135		(void)pao_tmp__;					\
136	}								\
137	switch (sizeof(var)) {						\
138	case 1:								\
139		if (pao_ID__ == 1)					\
140			asm("incb "__percpu_arg(0) : "+m" (var));	\
141		else if (pao_ID__ == -1)				\
142			asm("decb "__percpu_arg(0) : "+m" (var));	\
143		else							\
144			asm("addb %1, "__percpu_arg(0)			\
145			    : "+m" (var)				\
146			    : "qi" ((pao_T__)(val)));			\
147		break;							\
148	case 2:								\
149		if (pao_ID__ == 1)					\
150			asm("incw "__percpu_arg(0) : "+m" (var));	\
151		else if (pao_ID__ == -1)				\
152			asm("decw "__percpu_arg(0) : "+m" (var));	\
153		else							\
154			asm("addw %1, "__percpu_arg(0)			\
155			    : "+m" (var)				\
156			    : "ri" ((pao_T__)(val)));			\
157		break;							\
158	case 4:								\
159		if (pao_ID__ == 1)					\
160			asm("incl "__percpu_arg(0) : "+m" (var));	\
161		else if (pao_ID__ == -1)				\
162			asm("decl "__percpu_arg(0) : "+m" (var));	\
163		else							\
164			asm("addl %1, "__percpu_arg(0)			\
165			    : "+m" (var)				\
166			    : "ri" ((pao_T__)(val)));			\
167		break;							\
168	case 8:								\
169		if (pao_ID__ == 1)					\
170			asm("incq "__percpu_arg(0) : "+m" (var));	\
171		else if (pao_ID__ == -1)				\
172			asm("decq "__percpu_arg(0) : "+m" (var));	\
173		else							\
174			asm("addq %1, "__percpu_arg(0)			\
175			    : "+m" (var)				\
176			    : "re" ((pao_T__)(val)));			\
177		break;							\
178	default: __bad_percpu_size();					\
179	}								\
180} while (0)
181
182#define percpu_from_op(op, var)				\
183({							\
184	typeof(var) pfo_ret__;				\
185	switch (sizeof(var)) {				\
186	case 1:						\
187		asm(op "b "__percpu_arg(1)",%0"		\
188		    : "=q" (pfo_ret__)			\
189		    : "m" (var));			\
190		break;					\
191	case 2:						\
192		asm(op "w "__percpu_arg(1)",%0"		\
193		    : "=r" (pfo_ret__)			\
194		    : "m" (var));			\
195		break;					\
196	case 4:						\
197		asm(op "l "__percpu_arg(1)",%0"		\
198		    : "=r" (pfo_ret__)			\
199		    : "m" (var));			\
200		break;					\
201	case 8:						\
202		asm(op "q "__percpu_arg(1)",%0"		\
203		    : "=r" (pfo_ret__)			\
204		    : "m" (var));			\
205		break;					\
206	default: __bad_percpu_size();			\
207	}						\
208	pfo_ret__;					\
209})
210
211#define percpu_stable_op(op, var)			\
212({							\
213	typeof(var) pfo_ret__;				\
214	switch (sizeof(var)) {				\
215	case 1:						\
216		asm(op "b "__percpu_arg(P1)",%0"	\
217		    : "=q" (pfo_ret__)			\
218		    : "p" (&(var)));			\
219		break;					\
220	case 2:						\
221		asm(op "w "__percpu_arg(P1)",%0"	\
222		    : "=r" (pfo_ret__)			\
223		    : "p" (&(var)));			\
224		break;					\
225	case 4:						\
226		asm(op "l "__percpu_arg(P1)",%0"	\
227		    : "=r" (pfo_ret__)			\
228		    : "p" (&(var)));			\
229		break;					\
230	case 8:						\
231		asm(op "q "__percpu_arg(P1)",%0"	\
232		    : "=r" (pfo_ret__)			\
233		    : "p" (&(var)));			\
234		break;					\
235	default: __bad_percpu_size();			\
236	}						\
237	pfo_ret__;					\
238})
239
240#define percpu_unary_op(op, var)			\
241({							\
242	switch (sizeof(var)) {				\
243	case 1:						\
244		asm(op "b "__percpu_arg(0)		\
245		    : "+m" (var));			\
246		break;					\
247	case 2:						\
248		asm(op "w "__percpu_arg(0)		\
249		    : "+m" (var));			\
250		break;					\
251	case 4:						\
252		asm(op "l "__percpu_arg(0)		\
253		    : "+m" (var));			\
254		break;					\
255	case 8:						\
256		asm(op "q "__percpu_arg(0)		\
257		    : "+m" (var));			\
258		break;					\
259	default: __bad_percpu_size();			\
260	}						\
261})
262
263/*
264 * Add return operation
265 */
266#define percpu_add_return_op(var, val)					\
267({									\
268	typeof(var) paro_ret__ = val;					\
269	switch (sizeof(var)) {						\
270	case 1:								\
271		asm("xaddb %0, "__percpu_arg(1)				\
272			    : "+q" (paro_ret__), "+m" (var)		\
273			    : : "memory");				\
274		break;							\
275	case 2:								\
276		asm("xaddw %0, "__percpu_arg(1)				\
277			    : "+r" (paro_ret__), "+m" (var)		\
278			    : : "memory");				\
279		break;							\
280	case 4:								\
281		asm("xaddl %0, "__percpu_arg(1)				\
282			    : "+r" (paro_ret__), "+m" (var)		\
283			    : : "memory");				\
284		break;							\
285	case 8:								\
286		asm("xaddq %0, "__percpu_arg(1)				\
287			    : "+re" (paro_ret__), "+m" (var)		\
288			    : : "memory");				\
289		break;							\
290	default: __bad_percpu_size();					\
291	}								\
292	paro_ret__ += val;						\
293	paro_ret__;							\
294})
295
296/*
297 * xchg is implemented using cmpxchg without a lock prefix. xchg is
298 * expensive due to the implied lock prefix.  The processor cannot prefetch
299 * cachelines if xchg is used.
300 */
301#define percpu_xchg_op(var, nval)					\
302({									\
303	typeof(var) pxo_ret__;						\
304	typeof(var) pxo_new__ = (nval);					\
305	switch (sizeof(var)) {						\
306	case 1:								\
307		asm("\n\tmov "__percpu_arg(1)",%%al"			\
308		    "\n1:\tcmpxchgb %2, "__percpu_arg(1)		\
309		    "\n\tjnz 1b"					\
310			    : "=&a" (pxo_ret__), "+m" (var)		\
311			    : "q" (pxo_new__)				\
312			    : "memory");				\
313		break;							\
314	case 2:								\
315		asm("\n\tmov "__percpu_arg(1)",%%ax"			\
316		    "\n1:\tcmpxchgw %2, "__percpu_arg(1)		\
317		    "\n\tjnz 1b"					\
318			    : "=&a" (pxo_ret__), "+m" (var)		\
319			    : "r" (pxo_new__)				\
320			    : "memory");				\
321		break;							\
322	case 4:								\
323		asm("\n\tmov "__percpu_arg(1)",%%eax"			\
324		    "\n1:\tcmpxchgl %2, "__percpu_arg(1)		\
325		    "\n\tjnz 1b"					\
326			    : "=&a" (pxo_ret__), "+m" (var)		\
327			    : "r" (pxo_new__)				\
328			    : "memory");				\
329		break;							\
330	case 8:								\
331		asm("\n\tmov "__percpu_arg(1)",%%rax"			\
332		    "\n1:\tcmpxchgq %2, "__percpu_arg(1)		\
333		    "\n\tjnz 1b"					\
334			    : "=&a" (pxo_ret__), "+m" (var)		\
335			    : "r" (pxo_new__)				\
336			    : "memory");				\
337		break;							\
338	default: __bad_percpu_size();					\
339	}								\
340	pxo_ret__;							\
341})
342
343/*
344 * cmpxchg has no such implied lock semantics as a result it is much
345 * more efficient for cpu local operations.
346 */
347#define percpu_cmpxchg_op(var, oval, nval)				\
348({									\
349	typeof(var) pco_ret__;						\
350	typeof(var) pco_old__ = (oval);					\
351	typeof(var) pco_new__ = (nval);					\
352	switch (sizeof(var)) {						\
353	case 1:								\
354		asm("cmpxchgb %2, "__percpu_arg(1)			\
355			    : "=a" (pco_ret__), "+m" (var)		\
356			    : "q" (pco_new__), "0" (pco_old__)		\
357			    : "memory");				\
358		break;							\
359	case 2:								\
360		asm("cmpxchgw %2, "__percpu_arg(1)			\
361			    : "=a" (pco_ret__), "+m" (var)		\
362			    : "r" (pco_new__), "0" (pco_old__)		\
363			    : "memory");				\
364		break;							\
365	case 4:								\
366		asm("cmpxchgl %2, "__percpu_arg(1)			\
367			    : "=a" (pco_ret__), "+m" (var)		\
368			    : "r" (pco_new__), "0" (pco_old__)		\
369			    : "memory");				\
370		break;							\
371	case 8:								\
372		asm("cmpxchgq %2, "__percpu_arg(1)			\
373			    : "=a" (pco_ret__), "+m" (var)		\
374			    : "r" (pco_new__), "0" (pco_old__)		\
375			    : "memory");				\
376		break;							\
377	default: __bad_percpu_size();					\
378	}								\
379	pco_ret__;							\
380})
381
382/*
383 * this_cpu_read() makes gcc load the percpu variable every time it is
384 * accessed while this_cpu_read_stable() allows the value to be cached.
385 * this_cpu_read_stable() is more efficient and can be used if its value
386 * is guaranteed to be valid across cpus.  The current users include
387 * get_current() and get_thread_info() both of which are actually
388 * per-thread variables implemented as per-cpu variables and thus
389 * stable for the duration of the respective task.
390 */
391#define this_cpu_read_stable(var)	percpu_stable_op("mov", var)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
392
393#define raw_cpu_read_1(pcp)		percpu_from_op("mov", pcp)
394#define raw_cpu_read_2(pcp)		percpu_from_op("mov", pcp)
395#define raw_cpu_read_4(pcp)		percpu_from_op("mov", pcp)
396
397#define raw_cpu_write_1(pcp, val)	percpu_to_op("mov", (pcp), val)
398#define raw_cpu_write_2(pcp, val)	percpu_to_op("mov", (pcp), val)
399#define raw_cpu_write_4(pcp, val)	percpu_to_op("mov", (pcp), val)
400#define raw_cpu_add_1(pcp, val)		percpu_add_op((pcp), val)
401#define raw_cpu_add_2(pcp, val)		percpu_add_op((pcp), val)
402#define raw_cpu_add_4(pcp, val)		percpu_add_op((pcp), val)
403#define raw_cpu_and_1(pcp, val)		percpu_to_op("and", (pcp), val)
404#define raw_cpu_and_2(pcp, val)		percpu_to_op("and", (pcp), val)
405#define raw_cpu_and_4(pcp, val)		percpu_to_op("and", (pcp), val)
406#define raw_cpu_or_1(pcp, val)		percpu_to_op("or", (pcp), val)
407#define raw_cpu_or_2(pcp, val)		percpu_to_op("or", (pcp), val)
408#define raw_cpu_or_4(pcp, val)		percpu_to_op("or", (pcp), val)
409#define raw_cpu_xchg_1(pcp, val)	percpu_xchg_op(pcp, val)
410#define raw_cpu_xchg_2(pcp, val)	percpu_xchg_op(pcp, val)
411#define raw_cpu_xchg_4(pcp, val)	percpu_xchg_op(pcp, val)
412
413#define this_cpu_read_1(pcp)		percpu_from_op("mov", pcp)
414#define this_cpu_read_2(pcp)		percpu_from_op("mov", pcp)
415#define this_cpu_read_4(pcp)		percpu_from_op("mov", pcp)
416#define this_cpu_write_1(pcp, val)	percpu_to_op("mov", (pcp), val)
417#define this_cpu_write_2(pcp, val)	percpu_to_op("mov", (pcp), val)
418#define this_cpu_write_4(pcp, val)	percpu_to_op("mov", (pcp), val)
419#define this_cpu_add_1(pcp, val)	percpu_add_op((pcp), val)
420#define this_cpu_add_2(pcp, val)	percpu_add_op((pcp), val)
421#define this_cpu_add_4(pcp, val)	percpu_add_op((pcp), val)
422#define this_cpu_and_1(pcp, val)	percpu_to_op("and", (pcp), val)
423#define this_cpu_and_2(pcp, val)	percpu_to_op("and", (pcp), val)
424#define this_cpu_and_4(pcp, val)	percpu_to_op("and", (pcp), val)
425#define this_cpu_or_1(pcp, val)		percpu_to_op("or", (pcp), val)
426#define this_cpu_or_2(pcp, val)		percpu_to_op("or", (pcp), val)
427#define this_cpu_or_4(pcp, val)		percpu_to_op("or", (pcp), val)
428#define this_cpu_xchg_1(pcp, nval)	percpu_xchg_op(pcp, nval)
429#define this_cpu_xchg_2(pcp, nval)	percpu_xchg_op(pcp, nval)
430#define this_cpu_xchg_4(pcp, nval)	percpu_xchg_op(pcp, nval)
431
432#define raw_cpu_add_return_1(pcp, val)		percpu_add_return_op(pcp, val)
433#define raw_cpu_add_return_2(pcp, val)		percpu_add_return_op(pcp, val)
434#define raw_cpu_add_return_4(pcp, val)		percpu_add_return_op(pcp, val)
435#define raw_cpu_cmpxchg_1(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
436#define raw_cpu_cmpxchg_2(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
437#define raw_cpu_cmpxchg_4(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
438
439#define this_cpu_add_return_1(pcp, val)		percpu_add_return_op(pcp, val)
440#define this_cpu_add_return_2(pcp, val)		percpu_add_return_op(pcp, val)
441#define this_cpu_add_return_4(pcp, val)		percpu_add_return_op(pcp, val)
442#define this_cpu_cmpxchg_1(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
443#define this_cpu_cmpxchg_2(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
444#define this_cpu_cmpxchg_4(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
445
446#ifdef CONFIG_X86_CMPXCHG64
447#define percpu_cmpxchg8b_double(pcp1, pcp2, o1, o2, n1, n2)		\
448({									\
449	bool __ret;							\
450	typeof(pcp1) __o1 = (o1), __n1 = (n1);				\
451	typeof(pcp2) __o2 = (o2), __n2 = (n2);				\
452	asm volatile("cmpxchg8b "__percpu_arg(1)"\n\tsetz %0\n\t"	\
453		    : "=a" (__ret), "+m" (pcp1), "+m" (pcp2), "+d" (__o2) \
454		    :  "b" (__n1), "c" (__n2), "a" (__o1));		\
 
455	__ret;								\
456})
457
458#define raw_cpu_cmpxchg_double_4	percpu_cmpxchg8b_double
459#define this_cpu_cmpxchg_double_4	percpu_cmpxchg8b_double
460#endif /* CONFIG_X86_CMPXCHG64 */
461
462/*
463 * Per cpu atomic 64 bit operations are only available under 64 bit.
464 * 32 bit must fall back to generic operations.
465 */
466#ifdef CONFIG_X86_64
467#define raw_cpu_read_8(pcp)			percpu_from_op("mov", pcp)
468#define raw_cpu_write_8(pcp, val)		percpu_to_op("mov", (pcp), val)
469#define raw_cpu_add_8(pcp, val)			percpu_add_op((pcp), val)
470#define raw_cpu_and_8(pcp, val)			percpu_to_op("and", (pcp), val)
471#define raw_cpu_or_8(pcp, val)			percpu_to_op("or", (pcp), val)
472#define raw_cpu_add_return_8(pcp, val)		percpu_add_return_op(pcp, val)
473#define raw_cpu_xchg_8(pcp, nval)		percpu_xchg_op(pcp, nval)
474#define raw_cpu_cmpxchg_8(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
475
476#define this_cpu_read_8(pcp)			percpu_from_op("mov", pcp)
477#define this_cpu_write_8(pcp, val)		percpu_to_op("mov", (pcp), val)
478#define this_cpu_add_8(pcp, val)		percpu_add_op((pcp), val)
479#define this_cpu_and_8(pcp, val)		percpu_to_op("and", (pcp), val)
480#define this_cpu_or_8(pcp, val)			percpu_to_op("or", (pcp), val)
481#define this_cpu_add_return_8(pcp, val)		percpu_add_return_op(pcp, val)
482#define this_cpu_xchg_8(pcp, nval)		percpu_xchg_op(pcp, nval)
483#define this_cpu_cmpxchg_8(pcp, oval, nval)	percpu_cmpxchg_op(pcp, oval, nval)
484
485/*
486 * Pretty complex macro to generate cmpxchg16 instruction.  The instruction
487 * is not supported on early AMD64 processors so we must be able to emulate
488 * it in software.  The address used in the cmpxchg16 instruction must be
489 * aligned to a 16 byte boundary.
490 */
491#define percpu_cmpxchg16b_double(pcp1, pcp2, o1, o2, n1, n2)		\
492({									\
493	bool __ret;							\
494	typeof(pcp1) __o1 = (o1), __n1 = (n1);				\
495	typeof(pcp2) __o2 = (o2), __n2 = (n2);				\
496	alternative_io("leaq %P1,%%rsi\n\tcall this_cpu_cmpxchg16b_emu\n\t", \
497		       "cmpxchg16b " __percpu_arg(1) "\n\tsetz %0\n\t",	\
498		       X86_FEATURE_CX16,				\
499		       ASM_OUTPUT2("=a" (__ret), "+m" (pcp1),		\
500				   "+m" (pcp2), "+d" (__o2)),		\
501		       "b" (__n1), "c" (__n2), "a" (__o1) : "rsi");	\
502	__ret;								\
503})
504
505#define raw_cpu_cmpxchg_double_8	percpu_cmpxchg16b_double
506#define this_cpu_cmpxchg_double_8	percpu_cmpxchg16b_double
507
508#endif
509
510static __always_inline bool x86_this_cpu_constant_test_bit(unsigned int nr,
511                        const unsigned long __percpu *addr)
512{
513	unsigned long __percpu *a =
514		(unsigned long __percpu *)addr + nr / BITS_PER_LONG;
515
516#ifdef CONFIG_X86_64
517	return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_8(*a)) != 0;
518#else
519	return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_4(*a)) != 0;
520#endif
521}
522
523static inline bool x86_this_cpu_variable_test_bit(int nr,
524                        const unsigned long __percpu *addr)
525{
526	bool oldbit;
527
528	asm volatile("bt "__percpu_arg(2)",%1\n\t"
529			CC_SET(c)
530			: CC_OUT(c) (oldbit)
531			: "m" (*(unsigned long __percpu *)addr), "Ir" (nr));
532
533	return oldbit;
534}
535
536#define x86_this_cpu_test_bit(nr, addr)			\
537	(__builtin_constant_p((nr))			\
538	 ? x86_this_cpu_constant_test_bit((nr), (addr))	\
539	 : x86_this_cpu_variable_test_bit((nr), (addr)))
540
541
542#include <asm-generic/percpu.h>
543
544/* We can use this directly for local CPU (faster). */
545DECLARE_PER_CPU_READ_MOSTLY(unsigned long, this_cpu_off);
546
547#endif /* !__ASSEMBLY__ */
548
549#ifdef CONFIG_SMP
550
551/*
552 * Define the "EARLY_PER_CPU" macros.  These are used for some per_cpu
553 * variables that are initialized and accessed before there are per_cpu
554 * areas allocated.
555 */
556
557#define	DEFINE_EARLY_PER_CPU(_type, _name, _initvalue)			\
558	DEFINE_PER_CPU(_type, _name) = _initvalue;			\
559	__typeof__(_type) _name##_early_map[NR_CPUS] __initdata =	\
560				{ [0 ... NR_CPUS-1] = _initvalue };	\
561	__typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
562
563#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue)	\
564	DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue;		\
565	__typeof__(_type) _name##_early_map[NR_CPUS] __initdata =	\
566				{ [0 ... NR_CPUS-1] = _initvalue };	\
567	__typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
568
569#define EXPORT_EARLY_PER_CPU_SYMBOL(_name)			\
570	EXPORT_PER_CPU_SYMBOL(_name)
571
572#define DECLARE_EARLY_PER_CPU(_type, _name)			\
573	DECLARE_PER_CPU(_type, _name);				\
574	extern __typeof__(_type) *_name##_early_ptr;		\
575	extern __typeof__(_type)  _name##_early_map[]
576
577#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name)		\
578	DECLARE_PER_CPU_READ_MOSTLY(_type, _name);		\
579	extern __typeof__(_type) *_name##_early_ptr;		\
580	extern __typeof__(_type)  _name##_early_map[]
581
582#define	early_per_cpu_ptr(_name) (_name##_early_ptr)
583#define	early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
584#define	early_per_cpu(_name, _cpu) 				\
585	*(early_per_cpu_ptr(_name) ?				\
586		&early_per_cpu_ptr(_name)[_cpu] :		\
587		&per_cpu(_name, _cpu))
588
589#else	/* !CONFIG_SMP */
590#define	DEFINE_EARLY_PER_CPU(_type, _name, _initvalue)		\
591	DEFINE_PER_CPU(_type, _name) = _initvalue
592
593#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue)	\
594	DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue
595
596#define EXPORT_EARLY_PER_CPU_SYMBOL(_name)			\
597	EXPORT_PER_CPU_SYMBOL(_name)
598
599#define DECLARE_EARLY_PER_CPU(_type, _name)			\
600	DECLARE_PER_CPU(_type, _name)
601
602#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name)		\
603	DECLARE_PER_CPU_READ_MOSTLY(_type, _name)
604
605#define	early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
606#define	early_per_cpu_ptr(_name) NULL
607/* no early_per_cpu_map() */
608
609#endif	/* !CONFIG_SMP */
610
611#endif /* _ASM_X86_PERCPU_H */
v6.2
  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 */