1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_CPUMASK_H
3 #define __LINUX_CPUMASK_H
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.
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>
18 /* Don't assign or return these: may not be this big! */
19 typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
22 * cpumask_bits - get the bits in a cpumask
23 * @maskp: the struct cpumask *
25 * You should only assume nr_cpu_ids bits of this mask are valid. This is
26 * a macro so it's const-correct.
28 #define cpumask_bits(maskp) ((maskp)->bits)
31 * cpumask_pr_args - printf args to output a cpumask
32 * @maskp: cpumask to be printed
34 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
36 #define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp)
38 #if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
39 #define nr_cpu_ids ((unsigned int)NR_CPUS)
41 extern unsigned int nr_cpu_ids;
44 static inline void set_nr_cpu_ids(unsigned int nr)
46 #if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
47 WARN_ON(nr != nr_cpu_ids);
54 * We have several different "preferred sizes" for the cpumask
55 * operations, depending on operation.
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'.
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'.
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'.
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.
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)
84 #define small_cpumask_bits nr_cpu_ids
85 #define large_cpumask_bits nr_cpu_ids
87 #define nr_cpumask_bits nr_cpu_ids
90 * The following particular system cpumasks and operations manage
91 * possible, present, active and online cpus.
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
98 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
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.
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.
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.
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
125 extern struct cpumask __cpu_possible_mask;
126 extern struct cpumask __cpu_online_mask;
127 extern struct cpumask __cpu_present_mask;
128 extern struct cpumask __cpu_active_mask;
129 extern 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)
136 extern atomic_t __num_online_cpus;
138 extern cpumask_t cpus_booted_once_mask;
140 static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits)
142 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
143 WARN_ON_ONCE(cpu >= bits);
144 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
147 /* verify cpu argument to cpumask_* operators */
148 static __always_inline unsigned int cpumask_check(unsigned int cpu)
150 cpu_max_bits_warn(cpu, small_cpumask_bits);
155 * cpumask_first - get the first cpu in a cpumask
156 * @srcp: the cpumask pointer
158 * Return: >= nr_cpu_ids if no cpus set.
160 static inline unsigned int cpumask_first(const struct cpumask *srcp)
162 return find_first_bit(cpumask_bits(srcp), small_cpumask_bits);
166 * cpumask_first_zero - get the first unset cpu in a cpumask
167 * @srcp: the cpumask pointer
169 * Return: >= nr_cpu_ids if all cpus are set.
171 static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
173 return find_first_zero_bit(cpumask_bits(srcp), small_cpumask_bits);
177 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
178 * @srcp1: the first input
179 * @srcp2: the second input
181 * Return: >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
184 unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
186 return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
190 * cpumask_last - get the last CPU in a cpumask
191 * @srcp: - the cpumask pointer
193 * Return: >= nr_cpumask_bits if no CPUs set.
195 static inline unsigned int cpumask_last(const struct cpumask *srcp)
197 return find_last_bit(cpumask_bits(srcp), small_cpumask_bits);
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
205 * Return: >= nr_cpu_ids if no further cpus set.
208 unsigned int cpumask_next(int n, const struct cpumask *srcp)
210 /* -1 is a legal arg here. */
213 return find_next_bit(cpumask_bits(srcp), small_cpumask_bits, n + 1);
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
221 * Return: >= nr_cpu_ids if no further cpus unset.
223 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
225 /* -1 is a legal arg here. */
228 return find_next_zero_bit(cpumask_bits(srcp), small_cpumask_bits, n+1);
232 /* Uniprocessor: there is only one valid CPU */
233 static inline unsigned int cpumask_local_spread(unsigned int i, int node)
238 static inline unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
239 const struct cpumask *src2p)
241 return cpumask_first_and(src1p, src2p);
244 static inline unsigned int cpumask_any_distribute(const struct cpumask *srcp)
246 return cpumask_first(srcp);
249 unsigned int cpumask_local_spread(unsigned int i, int node);
250 unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
251 const struct cpumask *src2p);
252 unsigned int cpumask_any_distribute(const struct cpumask *srcp);
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
261 * Return: >= nr_cpu_ids if no further cpus set in both.
264 unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
265 const struct cpumask *src2p)
267 /* -1 is a legal arg here. */
270 return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p),
271 small_cpumask_bits, n + 1);
275 * for_each_cpu - iterate over every cpu in a mask
276 * @cpu: the (optionally unsigned) integer iterator
277 * @mask: the cpumask pointer
279 * After the loop, cpu is >= nr_cpu_ids.
281 #define for_each_cpu(cpu, mask) \
282 for_each_set_bit(cpu, cpumask_bits(mask), small_cpumask_bits)
286 unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap)
288 cpumask_check(start);
293 * Return the first available CPU when wrapping, or when starting before cpu0,
294 * since there is only one valid option.
297 return nr_cpumask_bits;
299 return cpumask_first(mask);
302 unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap);
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
311 * The implementation does not assume any bit in @mask is set (including @start).
313 * After the loop, cpu is >= nr_cpu_ids.
315 #define for_each_cpu_wrap(cpu, mask, start) \
316 for_each_set_bit_wrap(cpu, cpumask_bits(mask), small_cpumask_bits, start)
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
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)
330 * After the loop, cpu is >= nr_cpu_ids.
332 #define for_each_cpu_and(cpu, mask1, mask2) \
333 for_each_and_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
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
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)
348 * After the loop, cpu is >= nr_cpu_ids.
350 #define for_each_cpu_andnot(cpu, mask1, mask2) \
351 for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
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
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)
365 * After the loop, cpu is >= nr_cpu_ids.
367 #define for_each_cpu_or(cpu, mask1, mask2) \
368 for_each_or_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
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.
375 * Often used to find any cpu but smp_processor_id() in a mask.
376 * Return: >= nr_cpu_ids if no cpus set.
379 unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
384 for_each_cpu(i, mask)
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
395 * Return: >= nr_cpu_ids if such cpu doesn't exist.
397 static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp)
399 return find_nth_bit(cpumask_bits(srcp), small_cpumask_bits, cpumask_check(cpu));
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
408 * Return: >= nr_cpu_ids if such cpu doesn't exist.
411 unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1,
412 const struct cpumask *srcp2)
414 return find_nth_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
415 small_cpumask_bits, cpumask_check(cpu));
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
424 * Return: >= nr_cpu_ids if such cpu doesn't exist.
427 unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1,
428 const struct cpumask *srcp2)
430 return find_nth_andnot_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
431 small_cpumask_bits, cpumask_check(cpu));
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
441 * Return: >= nr_cpu_ids if such cpu doesn't exist.
443 static __always_inline
444 unsigned int cpumask_nth_and_andnot(unsigned int cpu, const struct cpumask *srcp1,
445 const struct cpumask *srcp2,
446 const struct cpumask *srcp3)
448 return find_nth_and_andnot_bit(cpumask_bits(srcp1),
451 small_cpumask_bits, cpumask_check(cpu));
454 #define CPU_BITS_NONE \
456 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
459 #define CPU_BITS_CPU0 \
465 * cpumask_set_cpu - set a cpu in a cpumask
466 * @cpu: cpu number (< nr_cpu_ids)
467 * @dstp: the cpumask pointer
469 static __always_inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
471 set_bit(cpumask_check(cpu), cpumask_bits(dstp));
474 static __always_inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
476 __set_bit(cpumask_check(cpu), cpumask_bits(dstp));
481 * cpumask_clear_cpu - clear a cpu in a cpumask
482 * @cpu: cpu number (< nr_cpu_ids)
483 * @dstp: the cpumask pointer
485 static __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
487 clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
490 static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp)
492 __clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
496 * cpumask_test_cpu - test for a cpu in a cpumask
497 * @cpu: cpu number (< nr_cpu_ids)
498 * @cpumask: the cpumask pointer
500 * Return: true if @cpu is set in @cpumask, else returns false
502 static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
504 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
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
512 * test_and_set_bit wrapper for cpumasks.
514 * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
516 static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
518 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
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
526 * test_and_clear_bit wrapper for cpumasks.
528 * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
530 static __always_inline bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
532 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
536 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
537 * @dstp: the cpumask pointer
539 static inline void cpumask_setall(struct cpumask *dstp)
541 if (small_const_nbits(small_cpumask_bits)) {
542 cpumask_bits(dstp)[0] = BITMAP_LAST_WORD_MASK(nr_cpumask_bits);
545 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
549 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
550 * @dstp: the cpumask pointer
552 static inline void cpumask_clear(struct cpumask *dstp)
554 bitmap_zero(cpumask_bits(dstp), large_cpumask_bits);
558 * cpumask_and - *dstp = *src1p & *src2p
559 * @dstp: the cpumask result
560 * @src1p: the first input
561 * @src2p: the second input
563 * Return: false if *@dstp is empty, else returns true
565 static inline bool cpumask_and(struct cpumask *dstp,
566 const struct cpumask *src1p,
567 const struct cpumask *src2p)
569 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
570 cpumask_bits(src2p), small_cpumask_bits);
574 * cpumask_or - *dstp = *src1p | *src2p
575 * @dstp: the cpumask result
576 * @src1p: the first input
577 * @src2p: the second input
579 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
580 const struct cpumask *src2p)
582 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
583 cpumask_bits(src2p), small_cpumask_bits);
587 * cpumask_xor - *dstp = *src1p ^ *src2p
588 * @dstp: the cpumask result
589 * @src1p: the first input
590 * @src2p: the second input
592 static inline void cpumask_xor(struct cpumask *dstp,
593 const struct cpumask *src1p,
594 const struct cpumask *src2p)
596 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
597 cpumask_bits(src2p), small_cpumask_bits);
601 * cpumask_andnot - *dstp = *src1p & ~*src2p
602 * @dstp: the cpumask result
603 * @src1p: the first input
604 * @src2p: the second input
606 * Return: false if *@dstp is empty, else returns true
608 static inline bool cpumask_andnot(struct cpumask *dstp,
609 const struct cpumask *src1p,
610 const struct cpumask *src2p)
612 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
613 cpumask_bits(src2p), small_cpumask_bits);
617 * cpumask_equal - *src1p == *src2p
618 * @src1p: the first input
619 * @src2p: the second input
621 * Return: true if the cpumasks are equal, false if not
623 static inline bool cpumask_equal(const struct cpumask *src1p,
624 const struct cpumask *src2p)
626 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
631 * cpumask_or_equal - *src1p | *src2p == *src3p
632 * @src1p: the first input
633 * @src2p: the second input
634 * @src3p: the third input
636 * Return: true if first cpumask ORed with second cpumask == third cpumask,
639 static inline bool cpumask_or_equal(const struct cpumask *src1p,
640 const struct cpumask *src2p,
641 const struct cpumask *src3p)
643 return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p),
644 cpumask_bits(src3p), small_cpumask_bits);
648 * cpumask_intersects - (*src1p & *src2p) != 0
649 * @src1p: the first input
650 * @src2p: the second input
652 * Return: true if first cpumask ANDed with second cpumask is non-empty,
655 static inline bool cpumask_intersects(const struct cpumask *src1p,
656 const struct cpumask *src2p)
658 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
663 * cpumask_subset - (*src1p & ~*src2p) == 0
664 * @src1p: the first input
665 * @src2p: the second input
667 * Return: true if *@src1p is a subset of *@src2p, else returns false
669 static inline bool cpumask_subset(const struct cpumask *src1p,
670 const struct cpumask *src2p)
672 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
677 * cpumask_empty - *srcp == 0
678 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
680 * Return: true if srcp is empty (has no bits set), else false
682 static inline bool cpumask_empty(const struct cpumask *srcp)
684 return bitmap_empty(cpumask_bits(srcp), small_cpumask_bits);
688 * cpumask_full - *srcp == 0xFFFFFFFF...
689 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
691 * Return: true if srcp is full (has all bits set), else false
693 static inline bool cpumask_full(const struct cpumask *srcp)
695 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
699 * cpumask_weight - Count of bits in *srcp
700 * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
702 * Return: count of bits set in *srcp
704 static inline unsigned int cpumask_weight(const struct cpumask *srcp)
706 return bitmap_weight(cpumask_bits(srcp), small_cpumask_bits);
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.
714 * Return: count of bits set in both *srcp1 and *srcp2
716 static inline unsigned int cpumask_weight_and(const struct cpumask *srcp1,
717 const struct cpumask *srcp2)
719 return bitmap_weight_and(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
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
728 static inline void cpumask_shift_right(struct cpumask *dstp,
729 const struct cpumask *srcp, int n)
731 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
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
741 static inline void cpumask_shift_left(struct cpumask *dstp,
742 const struct cpumask *srcp, int n)
744 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
749 * cpumask_copy - *dstp = *srcp
751 * @srcp: the input cpumask
753 static inline void cpumask_copy(struct cpumask *dstp,
754 const struct cpumask *srcp)
756 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), large_cpumask_bits);
760 * cpumask_any - pick a "random" cpu from *srcp
761 * @srcp: the input cpumask
763 * Return: >= nr_cpu_ids if no cpus set.
765 #define cpumask_any(srcp) cpumask_first(srcp)
768 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
769 * @mask1: the first input cpumask
770 * @mask2: the second input cpumask
772 * Return: >= nr_cpu_ids if no cpus set.
774 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
777 * cpumask_of - the cpumask containing just a given cpu
778 * @cpu: the cpu (<= nr_cpu_ids)
780 #define cpumask_of(cpu) (get_cpu_mask(cpu))
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.
788 * Return: -errno, or 0 for success.
790 static inline int cpumask_parse_user(const char __user *buf, int len,
791 struct cpumask *dstp)
793 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
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.
802 * Return: -errno, or 0 for success.
804 static inline int cpumask_parselist_user(const char __user *buf, int len,
805 struct cpumask *dstp)
807 return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
812 * cpumask_parse - extract a cpumask from a string
813 * @buf: the buffer to extract from
814 * @dstp: the cpumask to set.
816 * Return: -errno, or 0 for success.
818 static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
820 return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits);
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.
828 * Return: -errno, or 0 for success.
830 static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
832 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits);
836 * cpumask_size - calculate size to allocate for a 'struct cpumask' in bytes
838 * Return: size to allocate for a &struct cpumask in bytes
840 static inline unsigned int cpumask_size(void)
842 return BITS_TO_LONGS(large_cpumask_bits) * sizeof(long);
846 * cpumask_var_t: struct cpumask for stack usage.
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.
853 * cpumask_var_t tmpmask;
854 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
857 * ... use 'tmpmask' like a normal struct cpumask * ...
859 * free_cpumask_var(tmpmask);
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.
866 * cpumask_var_t tmpmask;
867 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
872 * This code makes NR_CPUS length memcopy and brings to a memory corruption.
873 * cpumask_copy() provide safe copy functionality.
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.
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.
885 #ifdef CONFIG_CPUMASK_OFFSTACK
886 typedef struct cpumask *cpumask_var_t;
888 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
889 #define __cpumask_var_read_mostly __read_mostly
891 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
894 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
896 return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node);
900 * alloc_cpumask_var - allocate a struct cpumask
901 * @mask: pointer to cpumask_var_t where the cpumask is returned
904 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
905 * a nop returning a constant 1 (in <linux/cpumask.h>).
907 * See alloc_cpumask_var_node.
909 * Return: %true if allocation succeeded, %false if not
912 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
914 return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE);
918 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
920 return alloc_cpumask_var(mask, flags | __GFP_ZERO);
923 void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
924 void free_cpumask_var(cpumask_var_t mask);
925 void free_bootmem_cpumask_var(cpumask_var_t mask);
927 static inline bool cpumask_available(cpumask_var_t mask)
933 typedef struct cpumask cpumask_var_t[1];
935 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
936 #define __cpumask_var_read_mostly
938 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
943 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
949 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
951 cpumask_clear(*mask);
955 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
958 cpumask_clear(*mask);
962 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
966 static inline void free_cpumask_var(cpumask_var_t mask)
970 static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
974 static inline bool cpumask_available(cpumask_var_t mask)
978 #endif /* CONFIG_CPUMASK_OFFSTACK */
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. */
982 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
983 #define cpu_all_mask to_cpumask(cpu_all_bits)
985 /* First bits of cpu_bit_bitmap are in fact unset. */
986 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
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)++)
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)
999 /* Wrappers for arch boot code to manipulate normally-constant masks */
1000 void init_cpu_present(const struct cpumask *src);
1001 void init_cpu_possible(const struct cpumask *src);
1002 void init_cpu_online(const struct cpumask *src);
1004 static inline void reset_cpu_possible_mask(void)
1006 bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS);
1010 set_cpu_possible(unsigned int cpu, bool possible)
1013 cpumask_set_cpu(cpu, &__cpu_possible_mask);
1015 cpumask_clear_cpu(cpu, &__cpu_possible_mask);
1019 set_cpu_present(unsigned int cpu, bool present)
1022 cpumask_set_cpu(cpu, &__cpu_present_mask);
1024 cpumask_clear_cpu(cpu, &__cpu_present_mask);
1027 void set_cpu_online(unsigned int cpu, bool online);
1030 set_cpu_active(unsigned int cpu, bool active)
1033 cpumask_set_cpu(cpu, &__cpu_active_mask);
1035 cpumask_clear_cpu(cpu, &__cpu_active_mask);
1039 set_cpu_dying(unsigned int cpu, bool dying)
1042 cpumask_set_cpu(cpu, &__cpu_dying_mask);
1044 cpumask_clear_cpu(cpu, &__cpu_dying_mask);
1048 * to_cpumask - convert a NR_CPUS bitmap to a struct cpumask *
1049 * @bitmap: the bitmap
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'.
1055 * This does the conversion, and can be used as a constant initializer.
1057 #define to_cpumask(bitmap) \
1058 ((struct cpumask *)(1 ? (bitmap) \
1059 : (void *)sizeof(__check_is_bitmap(bitmap))))
1061 static inline int __check_is_bitmap(const unsigned long *bitmap)
1067 * Special-case data structure for "single bit set only" constant CPU masks.
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.
1073 extern const unsigned long
1074 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
1076 static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
1078 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
1079 p -= cpu / BITS_PER_LONG;
1080 return to_cpumask(p);
1085 * num_online_cpus() - Read the number of online CPUs
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
1092 * Return: momentary snapshot of the number of online CPUs
1094 static __always_inline unsigned int num_online_cpus(void)
1096 return raw_atomic_read(&__num_online_cpus);
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)
1102 static inline bool cpu_online(unsigned int cpu)
1104 return cpumask_test_cpu(cpu, cpu_online_mask);
1107 static inline bool cpu_possible(unsigned int cpu)
1109 return cpumask_test_cpu(cpu, cpu_possible_mask);
1112 static inline bool cpu_present(unsigned int cpu)
1114 return cpumask_test_cpu(cpu, cpu_present_mask);
1117 static inline bool cpu_active(unsigned int cpu)
1119 return cpumask_test_cpu(cpu, cpu_active_mask);
1122 static inline bool cpu_dying(unsigned int cpu)
1124 return cpumask_test_cpu(cpu, cpu_dying_mask);
1129 #define num_online_cpus() 1U
1130 #define num_possible_cpus() 1U
1131 #define num_present_cpus() 1U
1132 #define num_active_cpus() 1U
1134 static inline bool cpu_online(unsigned int cpu)
1139 static inline bool cpu_possible(unsigned int cpu)
1144 static inline bool cpu_present(unsigned int cpu)
1149 static inline bool cpu_active(unsigned int cpu)
1154 static inline bool cpu_dying(unsigned int cpu)
1159 #endif /* NR_CPUS > 1 */
1161 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))
1163 #if NR_CPUS <= BITS_PER_LONG
1164 #define CPU_BITS_ALL \
1166 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1169 #else /* NR_CPUS > BITS_PER_LONG */
1171 #define CPU_BITS_ALL \
1173 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
1174 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1176 #endif /* NR_CPUS > BITS_PER_LONG */
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
1185 * Return: the length of the (null-terminated) @buf string, zero if
1186 * nothing is copied.
1188 static inline ssize_t
1189 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
1191 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
1196 * cpumap_print_bitmask_to_buf - copies the cpumask into the buffer as
1197 * hex values of cpumask
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
1204 * The function prints the cpumask into the buffer as hex values of
1205 * cpumask; Typically used by bin_attribute to export cpumask bitmask
1208 * Return: the length of how many bytes have been copied, excluding
1211 static inline ssize_t
1212 cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask,
1213 loff_t off, size_t count)
1215 return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask),
1216 nr_cpu_ids, off, count) - 1;
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
1227 * Everything is same with the above cpumap_print_bitmask_to_buf()
1228 * except the print format.
1230 * Return: the length of how many bytes have been copied, excluding
1233 static inline ssize_t
1234 cpumap_print_list_to_buf(char *buf, const struct cpumask *mask,
1235 loff_t off, size_t count)
1237 return bitmap_print_list_to_buf(buf, cpumask_bits(mask),
1238 nr_cpu_ids, off, count) - 1;
1241 #if NR_CPUS <= BITS_PER_LONG
1242 #define CPU_MASK_ALL \
1244 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1247 #define CPU_MASK_ALL \
1249 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
1250 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1252 #endif /* NR_CPUS > BITS_PER_LONG */
1254 #define CPU_MASK_NONE \
1256 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
1259 #define CPU_MASK_CPU0 \
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.
1269 * for cpumap NR_CPUS * 9/32 - 1 should be an exact length.
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.
1276 * Use PAGE_SIZE as a minimum for smaller configurations while avoiding
1277 * unsigned comparison to -1.
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)
1283 #endif /* __LINUX_CPUMASK_H */