1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_CPUMASK_H
3#define __LINUX_CPUMASK_H
4
5/*
6 * Cpumasks provide a bitmap suitable for representing the
7 * set of CPUs in a system, one bit position per CPU number. In general,
8 * only nr_cpu_ids (<= NR_CPUS) bits are valid.
9 */
10#include <linux/kernel.h>
11#include <linux/threads.h>
12#include <linux/bitmap.h>
13#include <linux/atomic.h>
14#include <linux/bug.h>
15#include <linux/gfp_types.h>
16#include <linux/numa.h>
17
18/* Don't assign or return these: may not be this big! */
19typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
20
21/**
22 * cpumask_bits - get the bits in a cpumask
23 * @maskp: the struct cpumask *
24 *
25 * You should only assume nr_cpu_ids bits of this mask are valid. This is
26 * a macro so it's const-correct.
27 */
28#define cpumask_bits(maskp) ((maskp)->bits)
29
30/**
31 * cpumask_pr_args - printf args to output a cpumask
32 * @maskp: cpumask to be printed
33 *
34 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
35 */
36#define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp)
37
38#if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
39#define nr_cpu_ids ((unsigned int)NR_CPUS)
40#else
41extern unsigned int nr_cpu_ids;
42#endif
43
44static inline void set_nr_cpu_ids(unsigned int nr)
45{
46#if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
47 WARN_ON(nr != nr_cpu_ids);
48#else
49 nr_cpu_ids = nr;
50#endif
51}
52
53/*
54 * We have several different "preferred sizes" for the cpumask
55 * operations, depending on operation.
56 *
57 * For example, the bitmap scanning and operating operations have
58 * optimized routines that work for the single-word case, but only when
59 * the size is constant. So if NR_CPUS fits in one single word, we are
60 * better off using that small constant, in order to trigger the
61 * optimized bit finding. That is 'small_cpumask_size'.
62 *
63 * The clearing and copying operations will similarly perform better
64 * with a constant size, but we limit that size arbitrarily to four
65 * words. We call this 'large_cpumask_size'.
66 *
67 * Finally, some operations just want the exact limit, either because
68 * they set bits or just don't have any faster fixed-sized versions. We
69 * call this just 'nr_cpumask_bits'.
70 *
71 * Note that these optional constants are always guaranteed to be at
72 * least as big as 'nr_cpu_ids' itself is, and all our cpumask
73 * allocations are at least that size (see cpumask_size()). The
74 * optimization comes from being able to potentially use a compile-time
75 * constant instead of a run-time generated exact number of CPUs.
76 */
77#if NR_CPUS <= BITS_PER_LONG
78 #define small_cpumask_bits ((unsigned int)NR_CPUS)
79 #define large_cpumask_bits ((unsigned int)NR_CPUS)
80#elif NR_CPUS <= 4*BITS_PER_LONG
81 #define small_cpumask_bits nr_cpu_ids
82 #define large_cpumask_bits ((unsigned int)NR_CPUS)
83#else
84 #define small_cpumask_bits nr_cpu_ids
85 #define large_cpumask_bits nr_cpu_ids
86#endif
87#define nr_cpumask_bits nr_cpu_ids
88
89/*
90 * The following particular system cpumasks and operations manage
91 * possible, present, active and online cpus.
92 *
93 * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
94 * cpu_present_mask - has bit 'cpu' set iff cpu is populated
95 * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler
96 * cpu_active_mask - has bit 'cpu' set iff cpu available to migration
97 *
98 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
99 *
100 * The cpu_possible_mask is fixed at boot time, as the set of CPU IDs
101 * that it is possible might ever be plugged in at anytime during the
102 * life of that system boot. The cpu_present_mask is dynamic(*),
103 * representing which CPUs are currently plugged in. And
104 * cpu_online_mask is the dynamic subset of cpu_present_mask,
105 * indicating those CPUs available for scheduling.
106 *
107 * If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
108 * depending on what ACPI reports as currently plugged in, otherwise
109 * cpu_present_mask is just a copy of cpu_possible_mask.
110 *
111 * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not
112 * hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
113 *
114 * Subtleties:
115 * 1) UP ARCHes (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
116 * assumption that their single CPU is online. The UP
117 * cpu_{online,possible,present}_masks are placebos. Changing them
118 * will have no useful affect on the following num_*_cpus()
119 * and cpu_*() macros in the UP case. This ugliness is a UP
120 * optimization - don't waste any instructions or memory references
121 * asking if you're online or how many CPUs there are if there is
122 * only one CPU.
123 */
124
125extern struct cpumask __cpu_possible_mask;
126extern struct cpumask __cpu_online_mask;
127extern struct cpumask __cpu_present_mask;
128extern struct cpumask __cpu_active_mask;
129extern struct cpumask __cpu_dying_mask;
130#define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask)
131#define cpu_online_mask ((const struct cpumask *)&__cpu_online_mask)
132#define cpu_present_mask ((const struct cpumask *)&__cpu_present_mask)
133#define cpu_active_mask ((const struct cpumask *)&__cpu_active_mask)
134#define cpu_dying_mask ((const struct cpumask *)&__cpu_dying_mask)
135
136extern atomic_t __num_online_cpus;
137
138extern cpumask_t cpus_booted_once_mask;
139
140static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits)
141{
142#ifdef CONFIG_DEBUG_PER_CPU_MAPS
143 WARN_ON_ONCE(cpu >= bits);
144#endif /* CONFIG_DEBUG_PER_CPU_MAPS */
145}
146
147/* verify cpu argument to cpumask_* operators */
148static __always_inline unsigned int cpumask_check(unsigned int cpu)
149{
150 cpu_max_bits_warn(cpu, small_cpumask_bits);
151 return cpu;
152}
153
154/**
155 * cpumask_first - get the first cpu in a cpumask
156 * @srcp: the cpumask pointer
157 *
158 * Return: >= nr_cpu_ids if no cpus set.
159 */
160static inline unsigned int cpumask_first(const struct cpumask *srcp)
161{
162 return find_first_bit(cpumask_bits(srcp), small_cpumask_bits);
163}
164
165/**
166 * cpumask_first_zero - get the first unset cpu in a cpumask
167 * @srcp: the cpumask pointer
168 *
169 * Return: >= nr_cpu_ids if all cpus are set.
170 */
171static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
172{
173 return find_first_zero_bit(cpumask_bits(srcp), small_cpumask_bits);
174}
175
176/**
177 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
178 * @srcp1: the first input
179 * @srcp2: the second input
180 *
181 * Return: >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
182 */
183static inline
184unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
185{
186 return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
187}
188
189/**
190 * cpumask_last - get the last CPU in a cpumask
191 * @srcp: - the cpumask pointer
192 *
193 * Return: >= nr_cpumask_bits if no CPUs set.
194 */
195static inline unsigned int cpumask_last(const struct cpumask *srcp)
196{
197 return find_last_bit(cpumask_bits(srcp), small_cpumask_bits);
198}
199
200/**
201 * cpumask_next - get the next cpu in a cpumask
202 * @n: the cpu prior to the place to search (i.e. return will be > @n)
203 * @srcp: the cpumask pointer
204 *
205 * Return: >= nr_cpu_ids if no further cpus set.
206 */
207static inline
208unsigned int cpumask_next(int n, const struct cpumask *srcp)
209{
210 /* -1 is a legal arg here. */
211 if (n != -1)
212 cpumask_check(cpu: n);
213 return find_next_bit(cpumask_bits(srcp), small_cpumask_bits, offset: n + 1);
214}
215
216/**
217 * cpumask_next_zero - get the next unset cpu in a cpumask
218 * @n: the cpu prior to the place to search (i.e. return will be > @n)
219 * @srcp: the cpumask pointer
220 *
221 * Return: >= nr_cpu_ids if no further cpus unset.
222 */
223static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
224{
225 /* -1 is a legal arg here. */
226 if (n != -1)
227 cpumask_check(cpu: n);
228 return find_next_zero_bit(cpumask_bits(srcp), small_cpumask_bits, offset: n+1);
229}
230
231#if NR_CPUS == 1
232/* Uniprocessor: there is only one valid CPU */
233static inline unsigned int cpumask_local_spread(unsigned int i, int node)
234{
235 return 0;
236}
237
238static inline unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
239 const struct cpumask *src2p)
240{
241 return cpumask_first_and(src1p, src2p);
242}
243
244static inline unsigned int cpumask_any_distribute(const struct cpumask *srcp)
245{
246 return cpumask_first(srcp);
247}
248#else
249unsigned int cpumask_local_spread(unsigned int i, int node);
250unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
251 const struct cpumask *src2p);
252unsigned int cpumask_any_distribute(const struct cpumask *srcp);
253#endif /* NR_CPUS */
254
255/**
256 * cpumask_next_and - get the next cpu in *src1p & *src2p
257 * @n: the cpu prior to the place to search (i.e. return will be > @n)
258 * @src1p: the first cpumask pointer
259 * @src2p: the second cpumask pointer
260 *
261 * Return: >= nr_cpu_ids if no further cpus set in both.
262 */
263static inline
264unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
265 const struct cpumask *src2p)
266{
267 /* -1 is a legal arg here. */
268 if (n != -1)
269 cpumask_check(cpu: n);
270 return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p),
271 small_cpumask_bits, offset: n + 1);
272}
273
274/**
275 * for_each_cpu - iterate over every cpu in a mask
276 * @cpu: the (optionally unsigned) integer iterator
277 * @mask: the cpumask pointer
278 *
279 * After the loop, cpu is >= nr_cpu_ids.
280 */
281#define for_each_cpu(cpu, mask) \
282 for_each_set_bit(cpu, cpumask_bits(mask), small_cpumask_bits)
283
284#if NR_CPUS == 1
285static inline
286unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap)
287{
288 cpumask_check(start);
289 if (n != -1)
290 cpumask_check(n);
291
292 /*
293 * Return the first available CPU when wrapping, or when starting before cpu0,
294 * since there is only one valid option.
295 */
296 if (wrap && n >= 0)
297 return nr_cpumask_bits;
298
299 return cpumask_first(mask);
300}
301#else
302unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap);
303#endif
304
305/**
306 * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location
307 * @cpu: the (optionally unsigned) integer iterator
308 * @mask: the cpumask pointer
309 * @start: the start location
310 *
311 * The implementation does not assume any bit in @mask is set (including @start).
312 *
313 * After the loop, cpu is >= nr_cpu_ids.
314 */
315#define for_each_cpu_wrap(cpu, mask, start) \
316 for_each_set_bit_wrap(cpu, cpumask_bits(mask), small_cpumask_bits, start)
317
318/**
319 * for_each_cpu_and - iterate over every cpu in both masks
320 * @cpu: the (optionally unsigned) integer iterator
321 * @mask1: the first cpumask pointer
322 * @mask2: the second cpumask pointer
323 *
324 * This saves a temporary CPU mask in many places. It is equivalent to:
325 * struct cpumask tmp;
326 * cpumask_and(&tmp, &mask1, &mask2);
327 * for_each_cpu(cpu, &tmp)
328 * ...
329 *
330 * After the loop, cpu is >= nr_cpu_ids.
331 */
332#define for_each_cpu_and(cpu, mask1, mask2) \
333 for_each_and_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
334
335/**
336 * for_each_cpu_andnot - iterate over every cpu present in one mask, excluding
337 * those present in another.
338 * @cpu: the (optionally unsigned) integer iterator
339 * @mask1: the first cpumask pointer
340 * @mask2: the second cpumask pointer
341 *
342 * This saves a temporary CPU mask in many places. It is equivalent to:
343 * struct cpumask tmp;
344 * cpumask_andnot(&tmp, &mask1, &mask2);
345 * for_each_cpu(cpu, &tmp)
346 * ...
347 *
348 * After the loop, cpu is >= nr_cpu_ids.
349 */
350#define for_each_cpu_andnot(cpu, mask1, mask2) \
351 for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
352
353/**
354 * for_each_cpu_or - iterate over every cpu present in either mask
355 * @cpu: the (optionally unsigned) integer iterator
356 * @mask1: the first cpumask pointer
357 * @mask2: the second cpumask pointer
358 *
359 * This saves a temporary CPU mask in many places. It is equivalent to:
360 * struct cpumask tmp;
361 * cpumask_or(&tmp, &mask1, &mask2);
362 * for_each_cpu(cpu, &tmp)
363 * ...
364 *
365 * After the loop, cpu is >= nr_cpu_ids.
366 */
367#define for_each_cpu_or(cpu, mask1, mask2) \
368 for_each_or_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
369
370/**
371 * cpumask_any_but - return a "random" in a cpumask, but not this one.
372 * @mask: the cpumask to search
373 * @cpu: the cpu to ignore.
374 *
375 * Often used to find any cpu but smp_processor_id() in a mask.
376 * Return: >= nr_cpu_ids if no cpus set.
377 */
378static inline
379unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
380{
381 unsigned int i;
382
383 cpumask_check(cpu);
384 for_each_cpu(i, mask)
385 if (i != cpu)
386 break;
387 return i;
388}
389
390/**
391 * cpumask_nth - get the Nth cpu in a cpumask
392 * @srcp: the cpumask pointer
393 * @cpu: the Nth cpu to find, starting from 0
394 *
395 * Return: >= nr_cpu_ids if such cpu doesn't exist.
396 */
397static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp)
398{
399 return find_nth_bit(cpumask_bits(srcp), small_cpumask_bits, n: cpumask_check(cpu));
400}
401
402/**
403 * cpumask_nth_and - get the Nth cpu in 2 cpumasks
404 * @srcp1: the cpumask pointer
405 * @srcp2: the cpumask pointer
406 * @cpu: the Nth cpu to find, starting from 0
407 *
408 * Return: >= nr_cpu_ids if such cpu doesn't exist.
409 */
410static inline
411unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1,
412 const struct cpumask *srcp2)
413{
414 return find_nth_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
415 small_cpumask_bits, n: cpumask_check(cpu));
416}
417
418/**
419 * cpumask_nth_andnot - get the Nth cpu set in 1st cpumask, and clear in 2nd.
420 * @srcp1: the cpumask pointer
421 * @srcp2: the cpumask pointer
422 * @cpu: the Nth cpu to find, starting from 0
423 *
424 * Return: >= nr_cpu_ids if such cpu doesn't exist.
425 */
426static inline
427unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1,
428 const struct cpumask *srcp2)
429{
430 return find_nth_andnot_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
431 small_cpumask_bits, n: cpumask_check(cpu));
432}
433
434/**
435 * cpumask_nth_and_andnot - get the Nth cpu set in 1st and 2nd cpumask, and clear in 3rd.
436 * @srcp1: the cpumask pointer
437 * @srcp2: the cpumask pointer
438 * @srcp3: the cpumask pointer
439 * @cpu: the Nth cpu to find, starting from 0
440 *
441 * Return: >= nr_cpu_ids if such cpu doesn't exist.
442 */
443static __always_inline
444unsigned int cpumask_nth_and_andnot(unsigned int cpu, const struct cpumask *srcp1,
445 const struct cpumask *srcp2,
446 const struct cpumask *srcp3)
447{
448 return find_nth_and_andnot_bit(cpumask_bits(srcp1),
449 cpumask_bits(srcp2),
450 cpumask_bits(srcp3),
451 small_cpumask_bits, n: cpumask_check(cpu));
452}
453
454#define CPU_BITS_NONE \
455{ \
456 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
457}
458
459#define CPU_BITS_CPU0 \
460{ \
461 [0] = 1UL \
462}
463
464/**
465 * cpumask_set_cpu - set a cpu in a cpumask
466 * @cpu: cpu number (< nr_cpu_ids)
467 * @dstp: the cpumask pointer
468 */
469static __always_inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
470{
471 set_bit(nr: cpumask_check(cpu), cpumask_bits(dstp));
472}
473
474static __always_inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
475{
476 __set_bit(cpumask_check(cpu), cpumask_bits(dstp));
477}
478
479
480/**
481 * cpumask_clear_cpu - clear a cpu in a cpumask
482 * @cpu: cpu number (< nr_cpu_ids)
483 * @dstp: the cpumask pointer
484 */
485static __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
486{
487 clear_bit(nr: cpumask_check(cpu), cpumask_bits(dstp));
488}
489
490static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp)
491{
492 __clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
493}
494
495/**
496 * cpumask_test_cpu - test for a cpu in a cpumask
497 * @cpu: cpu number (< nr_cpu_ids)
498 * @cpumask: the cpumask pointer
499 *
500 * Return: true if @cpu is set in @cpumask, else returns false
501 */
502static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
503{
504 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
505}
506
507/**
508 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
509 * @cpu: cpu number (< nr_cpu_ids)
510 * @cpumask: the cpumask pointer
511 *
512 * test_and_set_bit wrapper for cpumasks.
513 *
514 * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
515 */
516static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
517{
518 return test_and_set_bit(nr: cpumask_check(cpu), cpumask_bits(cpumask));
519}
520
521/**
522 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
523 * @cpu: cpu number (< nr_cpu_ids)
524 * @cpumask: the cpumask pointer
525 *
526 * test_and_clear_bit wrapper for cpumasks.
527 *
528 * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
529 */
530static __always_inline bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
531{
532 return test_and_clear_bit(nr: cpumask_check(cpu), cpumask_bits(cpumask));
533}
534
535/**
536 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
537 * @dstp: the cpumask pointer
538 */
539static inline void cpumask_setall(struct cpumask *dstp)
540{
541 if (small_const_nbits(small_cpumask_bits)) {
542 cpumask_bits(dstp)[0] = BITMAP_LAST_WORD_MASK(nr_cpumask_bits);
543 return;
544 }
545 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
546}
547
548/**
549 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
550 * @dstp: the cpumask pointer
551 */
552static inline void cpumask_clear(struct cpumask *dstp)
553{
554 bitmap_zero(cpumask_bits(dstp), large_cpumask_bits);
555}
556
557/**
558 * cpumask_and - *dstp = *src1p & *src2p
559 * @dstp: the cpumask result
560 * @src1p: the first input
561 * @src2p: the second input
562 *
563 * Return: false if *@dstp is empty, else returns true
564 */
565static inline bool cpumask_and(struct cpumask *dstp,
566 const struct cpumask *src1p,
567 const struct cpumask *src2p)
568{
569 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
570 cpumask_bits(src2p), small_cpumask_bits);
571}
572
573/**
574 * cpumask_or - *dstp = *src1p | *src2p
575 * @dstp: the cpumask result
576 * @src1p: the first input
577 * @src2p: the second input
578 */
579static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
580 const struct cpumask *src2p)
581{
582 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
583 cpumask_bits(src2p), small_cpumask_bits);
584}
585
586/**
587 * cpumask_xor - *dstp = *src1p ^ *src2p
588 * @dstp: the cpumask result
589 * @src1p: the first input
590 * @src2p: the second input
591 */
592static inline void cpumask_xor(struct cpumask *dstp,
593 const struct cpumask *src1p,
594 const struct cpumask *src2p)
595{
596 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
597 cpumask_bits(src2p), small_cpumask_bits);
598}
599
600/**
601 * cpumask_andnot - *dstp = *src1p & ~*src2p
602 * @dstp: the cpumask result
603 * @src1p: the first input
604 * @src2p: the second input
605 *
606 * Return: false if *@dstp is empty, else returns true
607 */
608static inline bool cpumask_andnot(struct cpumask *dstp,
609 const struct cpumask *src1p,
610 const struct cpumask *src2p)
611{
612 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
613 cpumask_bits(src2p), small_cpumask_bits);
614}
615
616/**
617 * cpumask_equal - *src1p == *src2p
618 * @src1p: the first input
619 * @src2p: the second input
620 *
621 * Return: true if the cpumasks are equal, false if not
622 */
623static inline bool cpumask_equal(const struct cpumask *src1p,
624 const struct cpumask *src2p)
625{
626 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
627 small_cpumask_bits);
628}
629
630/**
631 * cpumask_or_equal - *src1p | *src2p == *src3p
632 * @src1p: the first input
633 * @src2p: the second input
634 * @src3p: the third input
635 *
636 * Return: true if first cpumask ORed with second cpumask == third cpumask,
637 * otherwise false
638 */
639static inline bool cpumask_or_equal(const struct cpumask *src1p,
640 const struct cpumask *src2p,
641 const struct cpumask *src3p)
642{
643 return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p),
644 cpumask_bits(src3p), small_cpumask_bits);
645}
646
647/**
648 * cpumask_intersects - (*src1p & *src2p) != 0
649 * @src1p: the first input
650 * @src2p: the second input
651 *
652 * Return: true if first cpumask ANDed with second cpumask is non-empty,
653 * otherwise false
654 */
655static inline bool cpumask_intersects(const struct cpumask *src1p,
656 const struct cpumask *src2p)
657{
658 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
659 small_cpumask_bits);
660}
661
662/**
663 * cpumask_subset - (*src1p & ~*src2p) == 0
664 * @src1p: the first input
665 * @src2p: the second input
666 *
667 * Return: true if *@src1p is a subset of *@src2p, else returns false
668 */
669static inline bool cpumask_subset(const struct cpumask *src1p,
670 const struct cpumask *src2p)
671{
672 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
673 small_cpumask_bits);
674}
675
676/**
677 * cpumask_empty - *srcp == 0
678 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
679 *
680 * Return: true if srcp is empty (has no bits set), else false
681 */
682static inline bool cpumask_empty(const struct cpumask *srcp)
683{
684 return bitmap_empty(cpumask_bits(srcp), small_cpumask_bits);
685}
686
687/**
688 * cpumask_full - *srcp == 0xFFFFFFFF...
689 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
690 *
691 * Return: true if srcp is full (has all bits set), else false
692 */
693static inline bool cpumask_full(const struct cpumask *srcp)
694{
695 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
696}
697
698/**
699 * cpumask_weight - Count of bits in *srcp
700 * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
701 *
702 * Return: count of bits set in *srcp
703 */
704static inline unsigned int cpumask_weight(const struct cpumask *srcp)
705{
706 return bitmap_weight(cpumask_bits(srcp), small_cpumask_bits);
707}
708
709/**
710 * cpumask_weight_and - Count of bits in (*srcp1 & *srcp2)
711 * @srcp1: the cpumask to count bits (< nr_cpu_ids) in.
712 * @srcp2: the cpumask to count bits (< nr_cpu_ids) in.
713 *
714 * Return: count of bits set in both *srcp1 and *srcp2
715 */
716static inline unsigned int cpumask_weight_and(const struct cpumask *srcp1,
717 const struct cpumask *srcp2)
718{
719 return bitmap_weight_and(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
720}
721
722/**
723 * cpumask_shift_right - *dstp = *srcp >> n
724 * @dstp: the cpumask result
725 * @srcp: the input to shift
726 * @n: the number of bits to shift by
727 */
728static inline void cpumask_shift_right(struct cpumask *dstp,
729 const struct cpumask *srcp, int n)
730{
731 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), shift: n,
732 small_cpumask_bits);
733}
734
735/**
736 * cpumask_shift_left - *dstp = *srcp << n
737 * @dstp: the cpumask result
738 * @srcp: the input to shift
739 * @n: the number of bits to shift by
740 */
741static inline void cpumask_shift_left(struct cpumask *dstp,
742 const struct cpumask *srcp, int n)
743{
744 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), shift: n,
745 nr_cpumask_bits);
746}
747
748/**
749 * cpumask_copy - *dstp = *srcp
750 * @dstp: the result
751 * @srcp: the input cpumask
752 */
753static inline void cpumask_copy(struct cpumask *dstp,
754 const struct cpumask *srcp)
755{
756 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), large_cpumask_bits);
757}
758
759/**
760 * cpumask_any - pick a "random" cpu from *srcp
761 * @srcp: the input cpumask
762 *
763 * Return: >= nr_cpu_ids if no cpus set.
764 */
765#define cpumask_any(srcp) cpumask_first(srcp)
766
767/**
768 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
769 * @mask1: the first input cpumask
770 * @mask2: the second input cpumask
771 *
772 * Return: >= nr_cpu_ids if no cpus set.
773 */
774#define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
775
776/**
777 * cpumask_of - the cpumask containing just a given cpu
778 * @cpu: the cpu (<= nr_cpu_ids)
779 */
780#define cpumask_of(cpu) (get_cpu_mask(cpu))
781
782/**
783 * cpumask_parse_user - extract a cpumask from a user string
784 * @buf: the buffer to extract from
785 * @len: the length of the buffer
786 * @dstp: the cpumask to set.
787 *
788 * Return: -errno, or 0 for success.
789 */
790static inline int cpumask_parse_user(const char __user *buf, int len,
791 struct cpumask *dstp)
792{
793 return bitmap_parse_user(ubuf: buf, ulen: len, cpumask_bits(dstp), nr_cpumask_bits);
794}
795
796/**
797 * cpumask_parselist_user - extract a cpumask from a user string
798 * @buf: the buffer to extract from
799 * @len: the length of the buffer
800 * @dstp: the cpumask to set.
801 *
802 * Return: -errno, or 0 for success.
803 */
804static inline int cpumask_parselist_user(const char __user *buf, int len,
805 struct cpumask *dstp)
806{
807 return bitmap_parselist_user(ubuf: buf, ulen: len, cpumask_bits(dstp),
808 nr_cpumask_bits);
809}
810
811/**
812 * cpumask_parse - extract a cpumask from a string
813 * @buf: the buffer to extract from
814 * @dstp: the cpumask to set.
815 *
816 * Return: -errno, or 0 for success.
817 */
818static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
819{
820 return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits);
821}
822
823/**
824 * cpulist_parse - extract a cpumask from a user string of ranges
825 * @buf: the buffer to extract from
826 * @dstp: the cpumask to set.
827 *
828 * Return: -errno, or 0 for success.
829 */
830static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
831{
832 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits);
833}
834
835/**
836 * cpumask_size - calculate size to allocate for a 'struct cpumask' in bytes
837 *
838 * Return: size to allocate for a &struct cpumask in bytes
839 */
840static inline unsigned int cpumask_size(void)
841{
842 return BITS_TO_LONGS(large_cpumask_bits) * sizeof(long);
843}
844
845/*
846 * cpumask_var_t: struct cpumask for stack usage.
847 *
848 * Oh, the wicked games we play! In order to make kernel coding a
849 * little more difficult, we typedef cpumask_var_t to an array or a
850 * pointer: doing &mask on an array is a noop, so it still works.
851 *
852 * i.e.
853 * cpumask_var_t tmpmask;
854 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
855 * return -ENOMEM;
856 *
857 * ... use 'tmpmask' like a normal struct cpumask * ...
858 *
859 * free_cpumask_var(tmpmask);
860 *
861 *
862 * However, one notable exception is there. alloc_cpumask_var() allocates
863 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has
864 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t.
865 *
866 * cpumask_var_t tmpmask;
867 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
868 * return -ENOMEM;
869 *
870 * var = *tmpmask;
871 *
872 * This code makes NR_CPUS length memcopy and brings to a memory corruption.
873 * cpumask_copy() provide safe copy functionality.
874 *
875 * Note that there is another evil here: If you define a cpumask_var_t
876 * as a percpu variable then the way to obtain the address of the cpumask
877 * structure differently influences what this_cpu_* operation needs to be
878 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use
879 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the
880 * other type of cpumask_var_t implementation is configured.
881 *
882 * Please also note that __cpumask_var_read_mostly can be used to declare
883 * a cpumask_var_t variable itself (not its content) as read mostly.
884 */
885#ifdef CONFIG_CPUMASK_OFFSTACK
886typedef struct cpumask *cpumask_var_t;
887
888#define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
889#define __cpumask_var_read_mostly __read_mostly
890
891bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
892
893static inline
894bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
895{
896 return alloc_cpumask_var_node(mask, flags: flags | __GFP_ZERO, node);
897}
898
899/**
900 * alloc_cpumask_var - allocate a struct cpumask
901 * @mask: pointer to cpumask_var_t where the cpumask is returned
902 * @flags: GFP_ flags
903 *
904 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
905 * a nop returning a constant 1 (in <linux/cpumask.h>).
906 *
907 * See alloc_cpumask_var_node.
908 *
909 * Return: %true if allocation succeeded, %false if not
910 */
911static inline
912bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
913{
914 return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE);
915}
916
917static inline
918bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
919{
920 return alloc_cpumask_var(mask, flags: flags | __GFP_ZERO);
921}
922
923void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
924void free_cpumask_var(cpumask_var_t mask);
925void free_bootmem_cpumask_var(cpumask_var_t mask);
926
927static inline bool cpumask_available(cpumask_var_t mask)
928{
929 return mask != NULL;
930}
931
932#else
933typedef struct cpumask cpumask_var_t[1];
934
935#define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
936#define __cpumask_var_read_mostly
937
938static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
939{
940 return true;
941}
942
943static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
944 int node)
945{
946 return true;
947}
948
949static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
950{
951 cpumask_clear(*mask);
952 return true;
953}
954
955static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
956 int node)
957{
958 cpumask_clear(*mask);
959 return true;
960}
961
962static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
963{
964}
965
966static inline void free_cpumask_var(cpumask_var_t mask)
967{
968}
969
970static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
971{
972}
973
974static inline bool cpumask_available(cpumask_var_t mask)
975{
976 return true;
977}
978#endif /* CONFIG_CPUMASK_OFFSTACK */
979
980/* It's common to want to use cpu_all_mask in struct member initializers,
981 * so it has to refer to an address rather than a pointer. */
982extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
983#define cpu_all_mask to_cpumask(cpu_all_bits)
984
985/* First bits of cpu_bit_bitmap are in fact unset. */
986#define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
987
988#if NR_CPUS == 1
989/* Uniprocessor: the possible/online/present masks are always "1" */
990#define for_each_possible_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
991#define for_each_online_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
992#define for_each_present_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
993#else
994#define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
995#define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask)
996#define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask)
997#endif
998
999/* Wrappers for arch boot code to manipulate normally-constant masks */
1000void init_cpu_present(const struct cpumask *src);
1001void init_cpu_possible(const struct cpumask *src);
1002void init_cpu_online(const struct cpumask *src);
1003
1004static inline void reset_cpu_possible_mask(void)
1005{
1006 bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS);
1007}
1008
1009static inline void
1010set_cpu_possible(unsigned int cpu, bool possible)
1011{
1012 if (possible)
1013 cpumask_set_cpu(cpu, dstp: &__cpu_possible_mask);
1014 else
1015 cpumask_clear_cpu(cpu, dstp: &__cpu_possible_mask);
1016}
1017
1018static inline void
1019set_cpu_present(unsigned int cpu, bool present)
1020{
1021 if (present)
1022 cpumask_set_cpu(cpu, dstp: &__cpu_present_mask);
1023 else
1024 cpumask_clear_cpu(cpu, dstp: &__cpu_present_mask);
1025}
1026
1027void set_cpu_online(unsigned int cpu, bool online);
1028
1029static inline void
1030set_cpu_active(unsigned int cpu, bool active)
1031{
1032 if (active)
1033 cpumask_set_cpu(cpu, dstp: &__cpu_active_mask);
1034 else
1035 cpumask_clear_cpu(cpu, dstp: &__cpu_active_mask);
1036}
1037
1038static inline void
1039set_cpu_dying(unsigned int cpu, bool dying)
1040{
1041 if (dying)
1042 cpumask_set_cpu(cpu, dstp: &__cpu_dying_mask);
1043 else
1044 cpumask_clear_cpu(cpu, dstp: &__cpu_dying_mask);
1045}
1046
1047/**
1048 * to_cpumask - convert a NR_CPUS bitmap to a struct cpumask *
1049 * @bitmap: the bitmap
1050 *
1051 * There are a few places where cpumask_var_t isn't appropriate and
1052 * static cpumasks must be used (eg. very early boot), yet we don't
1053 * expose the definition of 'struct cpumask'.
1054 *
1055 * This does the conversion, and can be used as a constant initializer.
1056 */
1057#define to_cpumask(bitmap) \
1058 ((struct cpumask *)(1 ? (bitmap) \
1059 : (void *)sizeof(__check_is_bitmap(bitmap))))
1060
1061static inline int __check_is_bitmap(const unsigned long *bitmap)
1062{
1063 return 1;
1064}
1065
1066/*
1067 * Special-case data structure for "single bit set only" constant CPU masks.
1068 *
1069 * We pre-generate all the 64 (or 32) possible bit positions, with enough
1070 * padding to the left and the right, and return the constant pointer
1071 * appropriately offset.
1072 */
1073extern const unsigned long
1074 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
1075
1076static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
1077{
1078 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
1079 p -= cpu / BITS_PER_LONG;
1080 return to_cpumask(p);
1081}
1082
1083#if NR_CPUS > 1
1084/**
1085 * num_online_cpus() - Read the number of online CPUs
1086 *
1087 * Despite the fact that __num_online_cpus is of type atomic_t, this
1088 * interface gives only a momentary snapshot and is not protected against
1089 * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held
1090 * region.
1091 *
1092 * Return: momentary snapshot of the number of online CPUs
1093 */
1094static __always_inline unsigned int num_online_cpus(void)
1095{
1096 return raw_atomic_read(v: &__num_online_cpus);
1097}
1098#define num_possible_cpus() cpumask_weight(cpu_possible_mask)
1099#define num_present_cpus() cpumask_weight(cpu_present_mask)
1100#define num_active_cpus() cpumask_weight(cpu_active_mask)
1101
1102static inline bool cpu_online(unsigned int cpu)
1103{
1104 return cpumask_test_cpu(cpu, cpu_online_mask);
1105}
1106
1107static inline bool cpu_possible(unsigned int cpu)
1108{
1109 return cpumask_test_cpu(cpu, cpu_possible_mask);
1110}
1111
1112static inline bool cpu_present(unsigned int cpu)
1113{
1114 return cpumask_test_cpu(cpu, cpu_present_mask);
1115}
1116
1117static inline bool cpu_active(unsigned int cpu)
1118{
1119 return cpumask_test_cpu(cpu, cpu_active_mask);
1120}
1121
1122static inline bool cpu_dying(unsigned int cpu)
1123{
1124 return cpumask_test_cpu(cpu, cpu_dying_mask);
1125}
1126
1127#else
1128
1129#define num_online_cpus() 1U
1130#define num_possible_cpus() 1U
1131#define num_present_cpus() 1U
1132#define num_active_cpus() 1U
1133
1134static inline bool cpu_online(unsigned int cpu)
1135{
1136 return cpu == 0;
1137}
1138
1139static inline bool cpu_possible(unsigned int cpu)
1140{
1141 return cpu == 0;
1142}
1143
1144static inline bool cpu_present(unsigned int cpu)
1145{
1146 return cpu == 0;
1147}
1148
1149static inline bool cpu_active(unsigned int cpu)
1150{
1151 return cpu == 0;
1152}
1153
1154static inline bool cpu_dying(unsigned int cpu)
1155{
1156 return false;
1157}
1158
1159#endif /* NR_CPUS > 1 */
1160
1161#define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))
1162
1163#if NR_CPUS <= BITS_PER_LONG
1164#define CPU_BITS_ALL \
1165{ \
1166 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1167}
1168
1169#else /* NR_CPUS > BITS_PER_LONG */
1170
1171#define CPU_BITS_ALL \
1172{ \
1173 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
1174 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1175}
1176#endif /* NR_CPUS > BITS_PER_LONG */
1177
1178/**
1179 * cpumap_print_to_pagebuf - copies the cpumask into the buffer either
1180 * as comma-separated list of cpus or hex values of cpumask
1181 * @list: indicates whether the cpumap must be list
1182 * @mask: the cpumask to copy
1183 * @buf: the buffer to copy into
1184 *
1185 * Return: the length of the (null-terminated) @buf string, zero if
1186 * nothing is copied.
1187 */
1188static inline ssize_t
1189cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
1190{
1191 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
1192 nmaskbits: nr_cpu_ids);
1193}
1194
1195/**
1196 * cpumap_print_bitmask_to_buf - copies the cpumask into the buffer as
1197 * hex values of cpumask
1198 *
1199 * @buf: the buffer to copy into
1200 * @mask: the cpumask to copy
1201 * @off: in the string from which we are copying, we copy to @buf
1202 * @count: the maximum number of bytes to print
1203 *
1204 * The function prints the cpumask into the buffer as hex values of
1205 * cpumask; Typically used by bin_attribute to export cpumask bitmask
1206 * ABI.
1207 *
1208 * Return: the length of how many bytes have been copied, excluding
1209 * terminating '\0'.
1210 */
1211static inline ssize_t
1212cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask,
1213 loff_t off, size_t count)
1214{
1215 return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask),
1216 nmaskbits: nr_cpu_ids, off, count) - 1;
1217}
1218
1219/**
1220 * cpumap_print_list_to_buf - copies the cpumask into the buffer as
1221 * comma-separated list of cpus
1222 * @buf: the buffer to copy into
1223 * @mask: the cpumask to copy
1224 * @off: in the string from which we are copying, we copy to @buf
1225 * @count: the maximum number of bytes to print
1226 *
1227 * Everything is same with the above cpumap_print_bitmask_to_buf()
1228 * except the print format.
1229 *
1230 * Return: the length of how many bytes have been copied, excluding
1231 * terminating '\0'.
1232 */
1233static inline ssize_t
1234cpumap_print_list_to_buf(char *buf, const struct cpumask *mask,
1235 loff_t off, size_t count)
1236{
1237 return bitmap_print_list_to_buf(buf, cpumask_bits(mask),
1238 nmaskbits: nr_cpu_ids, off, count) - 1;
1239}
1240
1241#if NR_CPUS <= BITS_PER_LONG
1242#define CPU_MASK_ALL \
1243(cpumask_t) { { \
1244 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1245} }
1246#else
1247#define CPU_MASK_ALL \
1248(cpumask_t) { { \
1249 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
1250 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1251} }
1252#endif /* NR_CPUS > BITS_PER_LONG */
1253
1254#define CPU_MASK_NONE \
1255(cpumask_t) { { \
1256 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
1257} }
1258
1259#define CPU_MASK_CPU0 \
1260(cpumask_t) { { \
1261 [0] = 1UL \
1262} }
1263
1264/*
1265 * Provide a valid theoretical max size for cpumap and cpulist sysfs files
1266 * to avoid breaking userspace which may allocate a buffer based on the size
1267 * reported by e.g. fstat.
1268 *
1269 * for cpumap NR_CPUS * 9/32 - 1 should be an exact length.
1270 *
1271 * For cpulist 7 is (ceil(log10(NR_CPUS)) + 1) allowing for NR_CPUS to be up
1272 * to 2 orders of magnitude larger than 8192. And then we divide by 2 to
1273 * cover a worst-case of every other cpu being on one of two nodes for a
1274 * very large NR_CPUS.
1275 *
1276 * Use PAGE_SIZE as a minimum for smaller configurations while avoiding
1277 * unsigned comparison to -1.
1278 */
1279#define CPUMAP_FILE_MAX_BYTES (((NR_CPUS * 9)/32 > PAGE_SIZE) \
1280 ? (NR_CPUS * 9)/32 - 1 : PAGE_SIZE)
1281#define CPULIST_FILE_MAX_BYTES (((NR_CPUS * 7)/2 > PAGE_SIZE) ? (NR_CPUS * 7)/2 : PAGE_SIZE)
1282
1283#endif /* __LINUX_CPUMASK_H */
1284

source code of linux/include/linux/cpumask.h