1#ifndef __LINUX_CPUMASK_H
2#define __LINUX_CPUMASK_H
3
4/*
5 * Cpumasks provide a bitmap suitable for representing the
6 * set of CPU's in a system, one bit position per CPU number.  In general,
7 * only nr_cpu_ids (<= NR_CPUS) bits are valid.
8 */
9#include <linux/kernel.h>
10#include <linux/threads.h>
11#include <linux/bitmap.h>
12#include <linux/bug.h>
13
14/* Don't assign or return these: may not be this big! */
15typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
16
17/**
18 * cpumask_bits - get the bits in a cpumask
19 * @maskp: the struct cpumask *
20 *
21 * You should only assume nr_cpu_ids bits of this mask are valid.  This is
22 * a macro so it's const-correct.
23 */
24#define cpumask_bits(maskp) ((maskp)->bits)
25
26/**
27 * cpumask_pr_args - printf args to output a cpumask
28 * @maskp: cpumask to be printed
29 *
30 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
31 */
32#define cpumask_pr_args(maskp)		nr_cpu_ids, cpumask_bits(maskp)
33
34#if NR_CPUS == 1
35#define nr_cpu_ids		1
36#else
37extern int nr_cpu_ids;
38#endif
39
40#ifdef CONFIG_CPUMASK_OFFSTACK
41/* Assuming NR_CPUS is huge, a runtime limit is more efficient.  Also,
42 * not all bits may be allocated. */
43#define nr_cpumask_bits	nr_cpu_ids
44#else
45#define nr_cpumask_bits	NR_CPUS
46#endif
47
48/*
49 * The following particular system cpumasks and operations manage
50 * possible, present, active and online cpus.
51 *
52 *     cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
53 *     cpu_present_mask - has bit 'cpu' set iff cpu is populated
54 *     cpu_online_mask  - has bit 'cpu' set iff cpu available to scheduler
55 *     cpu_active_mask  - has bit 'cpu' set iff cpu available to migration
56 *
57 *  If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
58 *
59 *  The cpu_possible_mask is fixed at boot time, as the set of CPU id's
60 *  that it is possible might ever be plugged in at anytime during the
61 *  life of that system boot.  The cpu_present_mask is dynamic(*),
62 *  representing which CPUs are currently plugged in.  And
63 *  cpu_online_mask is the dynamic subset of cpu_present_mask,
64 *  indicating those CPUs available for scheduling.
65 *
66 *  If HOTPLUG is enabled, then cpu_possible_mask is forced to have
67 *  all NR_CPUS bits set, otherwise it is just the set of CPUs that
68 *  ACPI reports present at boot.
69 *
70 *  If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
71 *  depending on what ACPI reports as currently plugged in, otherwise
72 *  cpu_present_mask is just a copy of cpu_possible_mask.
73 *
74 *  (*) Well, cpu_present_mask is dynamic in the hotplug case.  If not
75 *      hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
76 *
77 * Subtleties:
78 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
79 *    assumption that their single CPU is online.  The UP
80 *    cpu_{online,possible,present}_masks are placebos.  Changing them
81 *    will have no useful affect on the following num_*_cpus()
82 *    and cpu_*() macros in the UP case.  This ugliness is a UP
83 *    optimization - don't waste any instructions or memory references
84 *    asking if you're online or how many CPUs there are if there is
85 *    only one CPU.
86 */
87
88extern const struct cpumask *const cpu_possible_mask;
89extern const struct cpumask *const cpu_online_mask;
90extern const struct cpumask *const cpu_present_mask;
91extern const struct cpumask *const cpu_active_mask;
92
93#if NR_CPUS > 1
94#define num_online_cpus()	cpumask_weight(cpu_online_mask)
95#define num_possible_cpus()	cpumask_weight(cpu_possible_mask)
96#define num_present_cpus()	cpumask_weight(cpu_present_mask)
97#define num_active_cpus()	cpumask_weight(cpu_active_mask)
98#define cpu_online(cpu)		cpumask_test_cpu((cpu), cpu_online_mask)
99#define cpu_possible(cpu)	cpumask_test_cpu((cpu), cpu_possible_mask)
100#define cpu_present(cpu)	cpumask_test_cpu((cpu), cpu_present_mask)
101#define cpu_active(cpu)		cpumask_test_cpu((cpu), cpu_active_mask)
102#else
103#define num_online_cpus()	1U
104#define num_possible_cpus()	1U
105#define num_present_cpus()	1U
106#define num_active_cpus()	1U
107#define cpu_online(cpu)		((cpu) == 0)
108#define cpu_possible(cpu)	((cpu) == 0)
109#define cpu_present(cpu)	((cpu) == 0)
110#define cpu_active(cpu)		((cpu) == 0)
111#endif
112
113/* verify cpu argument to cpumask_* operators */
114static inline unsigned int cpumask_check(unsigned int cpu)
115{
116#ifdef CONFIG_DEBUG_PER_CPU_MAPS
117	WARN_ON_ONCE(cpu >= nr_cpumask_bits);
118#endif /* CONFIG_DEBUG_PER_CPU_MAPS */
119	return cpu;
120}
121
122#if NR_CPUS == 1
123/* Uniprocessor.  Assume all masks are "1". */
124static inline unsigned int cpumask_first(const struct cpumask *srcp)
125{
126	return 0;
127}
128
129/* Valid inputs for n are -1 and 0. */
130static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
131{
132	return n+1;
133}
134
135static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
136{
137	return n+1;
138}
139
140static inline unsigned int cpumask_next_and(int n,
141					    const struct cpumask *srcp,
142					    const struct cpumask *andp)
143{
144	return n+1;
145}
146
147/* cpu must be a valid cpu, ie 0, so there's no other choice. */
148static inline unsigned int cpumask_any_but(const struct cpumask *mask,
149					   unsigned int cpu)
150{
151	return 1;
152}
153
154static inline unsigned int cpumask_local_spread(unsigned int i, int node)
155{
156	return 0;
157}
158
159#define for_each_cpu(cpu, mask)			\
160	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
161#define for_each_cpu_not(cpu, mask)		\
162	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
163#define for_each_cpu_and(cpu, mask, and)	\
164	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)and)
165#else
166/**
167 * cpumask_first - get the first cpu in a cpumask
168 * @srcp: the cpumask pointer
169 *
170 * Returns >= nr_cpu_ids if no cpus set.
171 */
172static inline unsigned int cpumask_first(const struct cpumask *srcp)
173{
174	return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
175}
176
177/**
178 * cpumask_next - get the next cpu in a cpumask
179 * @n: the cpu prior to the place to search (ie. return will be > @n)
180 * @srcp: the cpumask pointer
181 *
182 * Returns >= nr_cpu_ids if no further cpus set.
183 */
184static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
185{
186	/* -1 is a legal arg here. */
187	if (n != -1)
188		cpumask_check(n);
189	return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
190}
191
192/**
193 * cpumask_next_zero - get the next unset cpu in a cpumask
194 * @n: the cpu prior to the place to search (ie. return will be > @n)
195 * @srcp: the cpumask pointer
196 *
197 * Returns >= nr_cpu_ids if no further cpus unset.
198 */
199static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
200{
201	/* -1 is a legal arg here. */
202	if (n != -1)
203		cpumask_check(n);
204	return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
205}
206
207int cpumask_next_and(int n, const struct cpumask *, const struct cpumask *);
208int cpumask_any_but(const struct cpumask *mask, unsigned int cpu);
209unsigned int cpumask_local_spread(unsigned int i, int node);
210
211/**
212 * for_each_cpu - iterate over every cpu in a mask
213 * @cpu: the (optionally unsigned) integer iterator
214 * @mask: the cpumask pointer
215 *
216 * After the loop, cpu is >= nr_cpu_ids.
217 */
218#define for_each_cpu(cpu, mask)				\
219	for ((cpu) = -1;				\
220		(cpu) = cpumask_next((cpu), (mask)),	\
221		(cpu) < nr_cpu_ids;)
222
223/**
224 * for_each_cpu_not - iterate over every cpu in a complemented mask
225 * @cpu: the (optionally unsigned) integer iterator
226 * @mask: the cpumask pointer
227 *
228 * After the loop, cpu is >= nr_cpu_ids.
229 */
230#define for_each_cpu_not(cpu, mask)				\
231	for ((cpu) = -1;					\
232		(cpu) = cpumask_next_zero((cpu), (mask)),	\
233		(cpu) < nr_cpu_ids;)
234
235/**
236 * for_each_cpu_and - iterate over every cpu in both masks
237 * @cpu: the (optionally unsigned) integer iterator
238 * @mask: the first cpumask pointer
239 * @and: the second cpumask pointer
240 *
241 * This saves a temporary CPU mask in many places.  It is equivalent to:
242 *	struct cpumask tmp;
243 *	cpumask_and(&tmp, &mask, &and);
244 *	for_each_cpu(cpu, &tmp)
245 *		...
246 *
247 * After the loop, cpu is >= nr_cpu_ids.
248 */
249#define for_each_cpu_and(cpu, mask, and)				\
250	for ((cpu) = -1;						\
251		(cpu) = cpumask_next_and((cpu), (mask), (and)),		\
252		(cpu) < nr_cpu_ids;)
253#endif /* SMP */
254
255#define CPU_BITS_NONE						\
256{								\
257	[0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL			\
258}
259
260#define CPU_BITS_CPU0						\
261{								\
262	[0] =  1UL						\
263}
264
265/**
266 * cpumask_set_cpu - set a cpu in a cpumask
267 * @cpu: cpu number (< nr_cpu_ids)
268 * @dstp: the cpumask pointer
269 */
270static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
271{
272	set_bit(cpumask_check(cpu), cpumask_bits(dstp));
273}
274
275/**
276 * cpumask_clear_cpu - clear a cpu in a cpumask
277 * @cpu: cpu number (< nr_cpu_ids)
278 * @dstp: the cpumask pointer
279 */
280static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
281{
282	clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
283}
284
285/**
286 * cpumask_test_cpu - test for a cpu in a cpumask
287 * @cpu: cpu number (< nr_cpu_ids)
288 * @cpumask: the cpumask pointer
289 *
290 * Returns 1 if @cpu is set in @cpumask, else returns 0
291 */
292static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
293{
294	return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
295}
296
297/**
298 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
299 * @cpu: cpu number (< nr_cpu_ids)
300 * @cpumask: the cpumask pointer
301 *
302 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
303 *
304 * test_and_set_bit wrapper for cpumasks.
305 */
306static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
307{
308	return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
309}
310
311/**
312 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
313 * @cpu: cpu number (< nr_cpu_ids)
314 * @cpumask: the cpumask pointer
315 *
316 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
317 *
318 * test_and_clear_bit wrapper for cpumasks.
319 */
320static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
321{
322	return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
323}
324
325/**
326 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
327 * @dstp: the cpumask pointer
328 */
329static inline void cpumask_setall(struct cpumask *dstp)
330{
331	bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
332}
333
334/**
335 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
336 * @dstp: the cpumask pointer
337 */
338static inline void cpumask_clear(struct cpumask *dstp)
339{
340	bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits);
341}
342
343/**
344 * cpumask_and - *dstp = *src1p & *src2p
345 * @dstp: the cpumask result
346 * @src1p: the first input
347 * @src2p: the second input
348 *
349 * If *@dstp is empty, returns 0, else returns 1
350 */
351static inline int cpumask_and(struct cpumask *dstp,
352			       const struct cpumask *src1p,
353			       const struct cpumask *src2p)
354{
355	return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
356				       cpumask_bits(src2p), nr_cpumask_bits);
357}
358
359/**
360 * cpumask_or - *dstp = *src1p | *src2p
361 * @dstp: the cpumask result
362 * @src1p: the first input
363 * @src2p: the second input
364 */
365static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
366			      const struct cpumask *src2p)
367{
368	bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
369				      cpumask_bits(src2p), nr_cpumask_bits);
370}
371
372/**
373 * cpumask_xor - *dstp = *src1p ^ *src2p
374 * @dstp: the cpumask result
375 * @src1p: the first input
376 * @src2p: the second input
377 */
378static inline void cpumask_xor(struct cpumask *dstp,
379			       const struct cpumask *src1p,
380			       const struct cpumask *src2p)
381{
382	bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
383				       cpumask_bits(src2p), nr_cpumask_bits);
384}
385
386/**
387 * cpumask_andnot - *dstp = *src1p & ~*src2p
388 * @dstp: the cpumask result
389 * @src1p: the first input
390 * @src2p: the second input
391 *
392 * If *@dstp is empty, returns 0, else returns 1
393 */
394static inline int cpumask_andnot(struct cpumask *dstp,
395				  const struct cpumask *src1p,
396				  const struct cpumask *src2p)
397{
398	return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
399					  cpumask_bits(src2p), nr_cpumask_bits);
400}
401
402/**
403 * cpumask_complement - *dstp = ~*srcp
404 * @dstp: the cpumask result
405 * @srcp: the input to invert
406 */
407static inline void cpumask_complement(struct cpumask *dstp,
408				      const struct cpumask *srcp)
409{
410	bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp),
411					      nr_cpumask_bits);
412}
413
414/**
415 * cpumask_equal - *src1p == *src2p
416 * @src1p: the first input
417 * @src2p: the second input
418 */
419static inline bool cpumask_equal(const struct cpumask *src1p,
420				const struct cpumask *src2p)
421{
422	return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
423						 nr_cpumask_bits);
424}
425
426/**
427 * cpumask_intersects - (*src1p & *src2p) != 0
428 * @src1p: the first input
429 * @src2p: the second input
430 */
431static inline bool cpumask_intersects(const struct cpumask *src1p,
432				     const struct cpumask *src2p)
433{
434	return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
435						      nr_cpumask_bits);
436}
437
438/**
439 * cpumask_subset - (*src1p & ~*src2p) == 0
440 * @src1p: the first input
441 * @src2p: the second input
442 *
443 * Returns 1 if *@src1p is a subset of *@src2p, else returns 0
444 */
445static inline int cpumask_subset(const struct cpumask *src1p,
446				 const struct cpumask *src2p)
447{
448	return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
449						  nr_cpumask_bits);
450}
451
452/**
453 * cpumask_empty - *srcp == 0
454 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
455 */
456static inline bool cpumask_empty(const struct cpumask *srcp)
457{
458	return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits);
459}
460
461/**
462 * cpumask_full - *srcp == 0xFFFFFFFF...
463 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
464 */
465static inline bool cpumask_full(const struct cpumask *srcp)
466{
467	return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
468}
469
470/**
471 * cpumask_weight - Count of bits in *srcp
472 * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
473 */
474static inline unsigned int cpumask_weight(const struct cpumask *srcp)
475{
476	return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits);
477}
478
479/**
480 * cpumask_shift_right - *dstp = *srcp >> n
481 * @dstp: the cpumask result
482 * @srcp: the input to shift
483 * @n: the number of bits to shift by
484 */
485static inline void cpumask_shift_right(struct cpumask *dstp,
486				       const struct cpumask *srcp, int n)
487{
488	bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
489					       nr_cpumask_bits);
490}
491
492/**
493 * cpumask_shift_left - *dstp = *srcp << n
494 * @dstp: the cpumask result
495 * @srcp: the input to shift
496 * @n: the number of bits to shift by
497 */
498static inline void cpumask_shift_left(struct cpumask *dstp,
499				      const struct cpumask *srcp, int n)
500{
501	bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
502					      nr_cpumask_bits);
503}
504
505/**
506 * cpumask_copy - *dstp = *srcp
507 * @dstp: the result
508 * @srcp: the input cpumask
509 */
510static inline void cpumask_copy(struct cpumask *dstp,
511				const struct cpumask *srcp)
512{
513	bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits);
514}
515
516/**
517 * cpumask_any - pick a "random" cpu from *srcp
518 * @srcp: the input cpumask
519 *
520 * Returns >= nr_cpu_ids if no cpus set.
521 */
522#define cpumask_any(srcp) cpumask_first(srcp)
523
524/**
525 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
526 * @src1p: the first input
527 * @src2p: the second input
528 *
529 * Returns >= nr_cpu_ids if no cpus set in both.  See also cpumask_next_and().
530 */
531#define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p))
532
533/**
534 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
535 * @mask1: the first input cpumask
536 * @mask2: the second input cpumask
537 *
538 * Returns >= nr_cpu_ids if no cpus set.
539 */
540#define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
541
542/**
543 * cpumask_of - the cpumask containing just a given cpu
544 * @cpu: the cpu (<= nr_cpu_ids)
545 */
546#define cpumask_of(cpu) (get_cpu_mask(cpu))
547
548/**
549 * cpumask_parse_user - extract a cpumask from a user string
550 * @buf: the buffer to extract from
551 * @len: the length of the buffer
552 * @dstp: the cpumask to set.
553 *
554 * Returns -errno, or 0 for success.
555 */
556static inline int cpumask_parse_user(const char __user *buf, int len,
557				     struct cpumask *dstp)
558{
559	return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpu_ids);
560}
561
562/**
563 * cpumask_parselist_user - extract a cpumask from a user string
564 * @buf: the buffer to extract from
565 * @len: the length of the buffer
566 * @dstp: the cpumask to set.
567 *
568 * Returns -errno, or 0 for success.
569 */
570static inline int cpumask_parselist_user(const char __user *buf, int len,
571				     struct cpumask *dstp)
572{
573	return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
574				     nr_cpu_ids);
575}
576
577/**
578 * cpumask_parse - extract a cpumask from from a string
579 * @buf: the buffer to extract from
580 * @dstp: the cpumask to set.
581 *
582 * Returns -errno, or 0 for success.
583 */
584static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
585{
586	char *nl = strchr(buf, '\n');
587	unsigned int len = nl ? (unsigned int)(nl - buf) : strlen(buf);
588
589	return bitmap_parse(buf, len, cpumask_bits(dstp), nr_cpu_ids);
590}
591
592/**
593 * cpulist_parse - extract a cpumask from a user string of ranges
594 * @buf: the buffer to extract from
595 * @dstp: the cpumask to set.
596 *
597 * Returns -errno, or 0 for success.
598 */
599static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
600{
601	return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpu_ids);
602}
603
604/**
605 * cpumask_size - size to allocate for a 'struct cpumask' in bytes
606 *
607 * This will eventually be a runtime variable, depending on nr_cpu_ids.
608 */
609static inline size_t cpumask_size(void)
610{
611	return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
612}
613
614/*
615 * cpumask_var_t: struct cpumask for stack usage.
616 *
617 * Oh, the wicked games we play!  In order to make kernel coding a
618 * little more difficult, we typedef cpumask_var_t to an array or a
619 * pointer: doing &mask on an array is a noop, so it still works.
620 *
621 * ie.
622 *	cpumask_var_t tmpmask;
623 *	if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
624 *		return -ENOMEM;
625 *
626 *	  ... use 'tmpmask' like a normal struct cpumask * ...
627 *
628 *	free_cpumask_var(tmpmask);
629 *
630 *
631 * However, one notable exception is there. alloc_cpumask_var() allocates
632 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has
633 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t.
634 *
635 *	cpumask_var_t tmpmask;
636 *	if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
637 *		return -ENOMEM;
638 *
639 *	var = *tmpmask;
640 *
641 * This code makes NR_CPUS length memcopy and brings to a memory corruption.
642 * cpumask_copy() provide safe copy functionality.
643 *
644 * Note that there is another evil here: If you define a cpumask_var_t
645 * as a percpu variable then the way to obtain the address of the cpumask
646 * structure differently influences what this_cpu_* operation needs to be
647 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use
648 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the
649 * other type of cpumask_var_t implementation is configured.
650 */
651#ifdef CONFIG_CPUMASK_OFFSTACK
652typedef struct cpumask *cpumask_var_t;
653
654#define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
655
656bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
657bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
658bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
659bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
660void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
661void free_cpumask_var(cpumask_var_t mask);
662void free_bootmem_cpumask_var(cpumask_var_t mask);
663
664#else
665typedef struct cpumask cpumask_var_t[1];
666
667#define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
668
669static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
670{
671	return true;
672}
673
674static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
675					  int node)
676{
677	return true;
678}
679
680static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
681{
682	cpumask_clear(*mask);
683	return true;
684}
685
686static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
687					  int node)
688{
689	cpumask_clear(*mask);
690	return true;
691}
692
693static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
694{
695}
696
697static inline void free_cpumask_var(cpumask_var_t mask)
698{
699}
700
701static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
702{
703}
704#endif /* CONFIG_CPUMASK_OFFSTACK */
705
706/* It's common to want to use cpu_all_mask in struct member initializers,
707 * so it has to refer to an address rather than a pointer. */
708extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
709#define cpu_all_mask to_cpumask(cpu_all_bits)
710
711/* First bits of cpu_bit_bitmap are in fact unset. */
712#define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
713
714#define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
715#define for_each_online_cpu(cpu)   for_each_cpu((cpu), cpu_online_mask)
716#define for_each_present_cpu(cpu)  for_each_cpu((cpu), cpu_present_mask)
717
718/* Wrappers for arch boot code to manipulate normally-constant masks */
719void set_cpu_possible(unsigned int cpu, bool possible);
720void set_cpu_present(unsigned int cpu, bool present);
721void set_cpu_online(unsigned int cpu, bool online);
722void set_cpu_active(unsigned int cpu, bool active);
723void init_cpu_present(const struct cpumask *src);
724void init_cpu_possible(const struct cpumask *src);
725void init_cpu_online(const struct cpumask *src);
726
727/**
728 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
729 * @bitmap: the bitmap
730 *
731 * There are a few places where cpumask_var_t isn't appropriate and
732 * static cpumasks must be used (eg. very early boot), yet we don't
733 * expose the definition of 'struct cpumask'.
734 *
735 * This does the conversion, and can be used as a constant initializer.
736 */
737#define to_cpumask(bitmap)						\
738	((struct cpumask *)(1 ? (bitmap)				\
739			    : (void *)sizeof(__check_is_bitmap(bitmap))))
740
741static inline int __check_is_bitmap(const unsigned long *bitmap)
742{
743	return 1;
744}
745
746/*
747 * Special-case data structure for "single bit set only" constant CPU masks.
748 *
749 * We pre-generate all the 64 (or 32) possible bit positions, with enough
750 * padding to the left and the right, and return the constant pointer
751 * appropriately offset.
752 */
753extern const unsigned long
754	cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
755
756static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
757{
758	const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
759	p -= cpu / BITS_PER_LONG;
760	return to_cpumask(p);
761}
762
763#define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))
764
765#if NR_CPUS <= BITS_PER_LONG
766#define CPU_BITS_ALL						\
767{								\
768	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
769}
770
771#else /* NR_CPUS > BITS_PER_LONG */
772
773#define CPU_BITS_ALL						\
774{								\
775	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,		\
776	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
777}
778#endif /* NR_CPUS > BITS_PER_LONG */
779
780/**
781 * cpumap_print_to_pagebuf  - copies the cpumask into the buffer either
782 *	as comma-separated list of cpus or hex values of cpumask
783 * @list: indicates whether the cpumap must be list
784 * @mask: the cpumask to copy
785 * @buf: the buffer to copy into
786 *
787 * Returns the length of the (null-terminated) @buf string, zero if
788 * nothing is copied.
789 */
790static inline ssize_t
791cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
792{
793	return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
794				      nr_cpu_ids);
795}
796
797#if NR_CPUS <= BITS_PER_LONG
798#define CPU_MASK_ALL							\
799(cpumask_t) { {								\
800	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
801} }
802#else
803#define CPU_MASK_ALL							\
804(cpumask_t) { {								\
805	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,			\
806	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
807} }
808#endif /* NR_CPUS > BITS_PER_LONG */
809
810#define CPU_MASK_NONE							\
811(cpumask_t) { {								\
812	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  0UL				\
813} }
814
815#define CPU_MASK_CPU0							\
816(cpumask_t) { {								\
817	[0] =  1UL							\
818} }
819
820#endif /* __LINUX_CPUMASK_H */
821