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 CPU's 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);
53 /* Deprecated. Always use nr_cpu_ids. */
54 #define nr_cpumask_bits nr_cpu_ids
57 * The following particular system cpumasks and operations manage
58 * possible, present, active and online cpus.
60 * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
61 * cpu_present_mask - has bit 'cpu' set iff cpu is populated
62 * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler
63 * cpu_active_mask - has bit 'cpu' set iff cpu available to migration
65 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
67 * The cpu_possible_mask is fixed at boot time, as the set of CPU id's
68 * that it is possible might ever be plugged in at anytime during the
69 * life of that system boot. The cpu_present_mask is dynamic(*),
70 * representing which CPUs are currently plugged in. And
71 * cpu_online_mask is the dynamic subset of cpu_present_mask,
72 * indicating those CPUs available for scheduling.
74 * If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
75 * depending on what ACPI reports as currently plugged in, otherwise
76 * cpu_present_mask is just a copy of cpu_possible_mask.
78 * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not
79 * hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
82 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
83 * assumption that their single CPU is online. The UP
84 * cpu_{online,possible,present}_masks are placebos. Changing them
85 * will have no useful affect on the following num_*_cpus()
86 * and cpu_*() macros in the UP case. This ugliness is a UP
87 * optimization - don't waste any instructions or memory references
88 * asking if you're online or how many CPUs there are if there is
92 extern struct cpumask __cpu_possible_mask;
93 extern struct cpumask __cpu_online_mask;
94 extern struct cpumask __cpu_present_mask;
95 extern struct cpumask __cpu_active_mask;
96 extern struct cpumask __cpu_dying_mask;
97 #define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask)
98 #define cpu_online_mask ((const struct cpumask *)&__cpu_online_mask)
99 #define cpu_present_mask ((const struct cpumask *)&__cpu_present_mask)
100 #define cpu_active_mask ((const struct cpumask *)&__cpu_active_mask)
101 #define cpu_dying_mask ((const struct cpumask *)&__cpu_dying_mask)
103 extern atomic_t __num_online_cpus;
105 extern cpumask_t cpus_booted_once_mask;
107 static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits)
109 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
110 WARN_ON_ONCE(cpu >= bits);
111 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
114 /* verify cpu argument to cpumask_* operators */
115 static __always_inline unsigned int cpumask_check(unsigned int cpu)
117 cpu_max_bits_warn(cpu, nr_cpumask_bits);
122 * cpumask_first - get the first cpu in a cpumask
123 * @srcp: the cpumask pointer
125 * Returns >= nr_cpu_ids if no cpus set.
127 static inline unsigned int cpumask_first(const struct cpumask *srcp)
129 return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
133 * cpumask_first_zero - get the first unset cpu in a cpumask
134 * @srcp: the cpumask pointer
136 * Returns >= nr_cpu_ids if all cpus are set.
138 static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
140 return find_first_zero_bit(cpumask_bits(srcp), nr_cpumask_bits);
144 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
145 * @src1p: the first input
146 * @src2p: the second input
148 * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
151 unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
153 return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), nr_cpumask_bits);
157 * cpumask_last - get the last CPU in a cpumask
158 * @srcp: - the cpumask pointer
160 * Returns >= nr_cpumask_bits if no CPUs set.
162 static inline unsigned int cpumask_last(const struct cpumask *srcp)
164 return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits);
168 * cpumask_next - get the next cpu in a cpumask
169 * @n: the cpu prior to the place to search (ie. return will be > @n)
170 * @srcp: the cpumask pointer
172 * Returns >= nr_cpu_ids if no further cpus set.
175 unsigned int cpumask_next(int n, const struct cpumask *srcp)
177 /* n is a prior cpu */
178 cpumask_check(n + 1);
179 return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1);
183 * cpumask_next_zero - get the next unset cpu in a cpumask
184 * @n: the cpu prior to the place to search (ie. return will be > @n)
185 * @srcp: the cpumask pointer
187 * Returns >= nr_cpu_ids if no further cpus unset.
189 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
191 /* n is a prior cpu */
192 cpumask_check(n + 1);
193 return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
197 /* Uniprocessor: there is only one valid CPU */
198 static inline unsigned int cpumask_local_spread(unsigned int i, int node)
203 static inline unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
204 const struct cpumask *src2p)
206 return cpumask_first_and(src1p, src2p);
209 static inline unsigned int cpumask_any_distribute(const struct cpumask *srcp)
211 return cpumask_first(srcp);
214 unsigned int cpumask_local_spread(unsigned int i, int node);
215 unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
216 const struct cpumask *src2p);
217 unsigned int cpumask_any_distribute(const struct cpumask *srcp);
221 * cpumask_next_and - get the next cpu in *src1p & *src2p
222 * @n: the cpu prior to the place to search (ie. return will be > @n)
223 * @src1p: the first cpumask pointer
224 * @src2p: the second cpumask pointer
226 * Returns >= nr_cpu_ids if no further cpus set in both.
229 unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
230 const struct cpumask *src2p)
232 /* n is a prior cpu */
233 cpumask_check(n + 1);
234 return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p),
235 nr_cpumask_bits, n + 1);
239 * for_each_cpu - iterate over every cpu in a mask
240 * @cpu: the (optionally unsigned) integer iterator
241 * @mask: the cpumask pointer
243 * After the loop, cpu is >= nr_cpu_ids.
245 #define for_each_cpu(cpu, mask) \
246 for_each_set_bit(cpu, cpumask_bits(mask), nr_cpumask_bits)
249 * for_each_cpu_not - iterate over every cpu in a complemented mask
250 * @cpu: the (optionally unsigned) integer iterator
251 * @mask: the cpumask pointer
253 * After the loop, cpu is >= nr_cpu_ids.
255 #define for_each_cpu_not(cpu, mask) \
256 for_each_clear_bit(cpu, cpumask_bits(mask), nr_cpumask_bits)
260 unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap)
262 cpumask_check(start);
263 /* n is a prior cpu */
264 cpumask_check(n + 1);
267 * Return the first available CPU when wrapping, or when starting before cpu0,
268 * since there is only one valid option.
271 return nr_cpumask_bits;
273 return cpumask_first(mask);
276 unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap);
280 * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location
281 * @cpu: the (optionally unsigned) integer iterator
282 * @mask: the cpumask pointer
283 * @start: the start location
285 * The implementation does not assume any bit in @mask is set (including @start).
287 * After the loop, cpu is >= nr_cpu_ids.
289 #define for_each_cpu_wrap(cpu, mask, start) \
290 for_each_set_bit_wrap(cpu, cpumask_bits(mask), nr_cpumask_bits, start)
293 * for_each_cpu_and - iterate over every cpu in both masks
294 * @cpu: the (optionally unsigned) integer iterator
295 * @mask1: the first cpumask pointer
296 * @mask2: the second cpumask pointer
298 * This saves a temporary CPU mask in many places. It is equivalent to:
299 * struct cpumask tmp;
300 * cpumask_and(&tmp, &mask1, &mask2);
301 * for_each_cpu(cpu, &tmp)
304 * After the loop, cpu is >= nr_cpu_ids.
306 #define for_each_cpu_and(cpu, mask1, mask2) \
307 for_each_and_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), nr_cpumask_bits)
310 * for_each_cpu_andnot - iterate over every cpu present in one mask, excluding
311 * those present in another.
312 * @cpu: the (optionally unsigned) integer iterator
313 * @mask1: the first cpumask pointer
314 * @mask2: the second cpumask pointer
316 * This saves a temporary CPU mask in many places. It is equivalent to:
317 * struct cpumask tmp;
318 * cpumask_andnot(&tmp, &mask1, &mask2);
319 * for_each_cpu(cpu, &tmp)
322 * After the loop, cpu is >= nr_cpu_ids.
324 #define for_each_cpu_andnot(cpu, mask1, mask2) \
325 for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), nr_cpumask_bits)
328 * cpumask_any_but - return a "random" in a cpumask, but not this one.
329 * @mask: the cpumask to search
330 * @cpu: the cpu to ignore.
332 * Often used to find any cpu but smp_processor_id() in a mask.
333 * Returns >= nr_cpu_ids if no cpus set.
336 unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
341 for_each_cpu(i, mask)
348 * cpumask_nth - get the first cpu in a cpumask
349 * @srcp: the cpumask pointer
350 * @cpu: the N'th cpu to find, starting from 0
352 * Returns >= nr_cpu_ids if such cpu doesn't exist.
354 static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp)
356 return find_nth_bit(cpumask_bits(srcp), nr_cpumask_bits, cpumask_check(cpu));
360 * cpumask_nth_and - get the first cpu in 2 cpumasks
361 * @srcp1: the cpumask pointer
362 * @srcp2: the cpumask pointer
363 * @cpu: the N'th cpu to find, starting from 0
365 * Returns >= nr_cpu_ids if such cpu doesn't exist.
368 unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1,
369 const struct cpumask *srcp2)
371 return find_nth_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
372 nr_cpumask_bits, cpumask_check(cpu));
376 * cpumask_nth_andnot - get the first cpu set in 1st cpumask, and clear in 2nd.
377 * @srcp1: the cpumask pointer
378 * @srcp2: the cpumask pointer
379 * @cpu: the N'th cpu to find, starting from 0
381 * Returns >= nr_cpu_ids if such cpu doesn't exist.
384 unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1,
385 const struct cpumask *srcp2)
387 return find_nth_andnot_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
388 nr_cpumask_bits, cpumask_check(cpu));
391 #define CPU_BITS_NONE \
393 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
396 #define CPU_BITS_CPU0 \
402 * cpumask_set_cpu - set a cpu in a cpumask
403 * @cpu: cpu number (< nr_cpu_ids)
404 * @dstp: the cpumask pointer
406 static __always_inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
408 set_bit(cpumask_check(cpu), cpumask_bits(dstp));
411 static __always_inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
413 __set_bit(cpumask_check(cpu), cpumask_bits(dstp));
418 * cpumask_clear_cpu - clear a cpu in a cpumask
419 * @cpu: cpu number (< nr_cpu_ids)
420 * @dstp: the cpumask pointer
422 static __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
424 clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
427 static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp)
429 __clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
433 * cpumask_test_cpu - test for a cpu in a cpumask
434 * @cpu: cpu number (< nr_cpu_ids)
435 * @cpumask: the cpumask pointer
437 * Returns true if @cpu is set in @cpumask, else returns false
439 static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
441 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
445 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
446 * @cpu: cpu number (< nr_cpu_ids)
447 * @cpumask: the cpumask pointer
449 * Returns true if @cpu is set in old bitmap of @cpumask, else returns false
451 * test_and_set_bit wrapper for cpumasks.
453 static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
455 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
459 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
460 * @cpu: cpu number (< nr_cpu_ids)
461 * @cpumask: the cpumask pointer
463 * Returns true if @cpu is set in old bitmap of @cpumask, else returns false
465 * test_and_clear_bit wrapper for cpumasks.
467 static __always_inline bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
469 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
473 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
474 * @dstp: the cpumask pointer
476 static inline void cpumask_setall(struct cpumask *dstp)
478 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
482 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
483 * @dstp: the cpumask pointer
485 static inline void cpumask_clear(struct cpumask *dstp)
487 bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits);
491 * cpumask_and - *dstp = *src1p & *src2p
492 * @dstp: the cpumask result
493 * @src1p: the first input
494 * @src2p: the second input
496 * If *@dstp is empty, returns false, else returns true
498 static inline bool cpumask_and(struct cpumask *dstp,
499 const struct cpumask *src1p,
500 const struct cpumask *src2p)
502 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
503 cpumask_bits(src2p), nr_cpumask_bits);
507 * cpumask_or - *dstp = *src1p | *src2p
508 * @dstp: the cpumask result
509 * @src1p: the first input
510 * @src2p: the second input
512 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
513 const struct cpumask *src2p)
515 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
516 cpumask_bits(src2p), nr_cpumask_bits);
520 * cpumask_xor - *dstp = *src1p ^ *src2p
521 * @dstp: the cpumask result
522 * @src1p: the first input
523 * @src2p: the second input
525 static inline void cpumask_xor(struct cpumask *dstp,
526 const struct cpumask *src1p,
527 const struct cpumask *src2p)
529 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
530 cpumask_bits(src2p), nr_cpumask_bits);
534 * cpumask_andnot - *dstp = *src1p & ~*src2p
535 * @dstp: the cpumask result
536 * @src1p: the first input
537 * @src2p: the second input
539 * If *@dstp is empty, returns false, else returns true
541 static inline bool cpumask_andnot(struct cpumask *dstp,
542 const struct cpumask *src1p,
543 const struct cpumask *src2p)
545 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
546 cpumask_bits(src2p), nr_cpumask_bits);
550 * cpumask_complement - *dstp = ~*srcp
551 * @dstp: the cpumask result
552 * @srcp: the input to invert
554 static inline void cpumask_complement(struct cpumask *dstp,
555 const struct cpumask *srcp)
557 bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp),
562 * cpumask_equal - *src1p == *src2p
563 * @src1p: the first input
564 * @src2p: the second input
566 static inline bool cpumask_equal(const struct cpumask *src1p,
567 const struct cpumask *src2p)
569 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
574 * cpumask_or_equal - *src1p | *src2p == *src3p
575 * @src1p: the first input
576 * @src2p: the second input
577 * @src3p: the third input
579 static inline bool cpumask_or_equal(const struct cpumask *src1p,
580 const struct cpumask *src2p,
581 const struct cpumask *src3p)
583 return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p),
584 cpumask_bits(src3p), nr_cpumask_bits);
588 * cpumask_intersects - (*src1p & *src2p) != 0
589 * @src1p: the first input
590 * @src2p: the second input
592 static inline bool cpumask_intersects(const struct cpumask *src1p,
593 const struct cpumask *src2p)
595 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
600 * cpumask_subset - (*src1p & ~*src2p) == 0
601 * @src1p: the first input
602 * @src2p: the second input
604 * Returns true if *@src1p is a subset of *@src2p, else returns false
606 static inline bool cpumask_subset(const struct cpumask *src1p,
607 const struct cpumask *src2p)
609 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
614 * cpumask_empty - *srcp == 0
615 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
617 static inline bool cpumask_empty(const struct cpumask *srcp)
619 return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits);
623 * cpumask_full - *srcp == 0xFFFFFFFF...
624 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
626 static inline bool cpumask_full(const struct cpumask *srcp)
628 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
632 * cpumask_weight - Count of bits in *srcp
633 * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
635 static inline unsigned int cpumask_weight(const struct cpumask *srcp)
637 return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits);
641 * cpumask_weight_and - Count of bits in (*srcp1 & *srcp2)
642 * @srcp1: the cpumask to count bits (< nr_cpu_ids) in.
643 * @srcp2: the cpumask to count bits (< nr_cpu_ids) in.
645 static inline unsigned int cpumask_weight_and(const struct cpumask *srcp1,
646 const struct cpumask *srcp2)
648 return bitmap_weight_and(cpumask_bits(srcp1), cpumask_bits(srcp2), nr_cpumask_bits);
652 * cpumask_shift_right - *dstp = *srcp >> n
653 * @dstp: the cpumask result
654 * @srcp: the input to shift
655 * @n: the number of bits to shift by
657 static inline void cpumask_shift_right(struct cpumask *dstp,
658 const struct cpumask *srcp, int n)
660 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
665 * cpumask_shift_left - *dstp = *srcp << n
666 * @dstp: the cpumask result
667 * @srcp: the input to shift
668 * @n: the number of bits to shift by
670 static inline void cpumask_shift_left(struct cpumask *dstp,
671 const struct cpumask *srcp, int n)
673 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
678 * cpumask_copy - *dstp = *srcp
680 * @srcp: the input cpumask
682 static inline void cpumask_copy(struct cpumask *dstp,
683 const struct cpumask *srcp)
685 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits);
689 * cpumask_any - pick a "random" cpu from *srcp
690 * @srcp: the input cpumask
692 * Returns >= nr_cpu_ids if no cpus set.
694 #define cpumask_any(srcp) cpumask_first(srcp)
697 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
698 * @mask1: the first input cpumask
699 * @mask2: the second input cpumask
701 * Returns >= nr_cpu_ids if no cpus set.
703 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
706 * cpumask_of - the cpumask containing just a given cpu
707 * @cpu: the cpu (<= nr_cpu_ids)
709 #define cpumask_of(cpu) (get_cpu_mask(cpu))
712 * cpumask_parse_user - extract a cpumask from a user string
713 * @buf: the buffer to extract from
714 * @len: the length of the buffer
715 * @dstp: the cpumask to set.
717 * Returns -errno, or 0 for success.
719 static inline int cpumask_parse_user(const char __user *buf, int len,
720 struct cpumask *dstp)
722 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
726 * cpumask_parselist_user - extract a cpumask from a user string
727 * @buf: the buffer to extract from
728 * @len: the length of the buffer
729 * @dstp: the cpumask to set.
731 * Returns -errno, or 0 for success.
733 static inline int cpumask_parselist_user(const char __user *buf, int len,
734 struct cpumask *dstp)
736 return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
741 * cpumask_parse - extract a cpumask from a string
742 * @buf: the buffer to extract from
743 * @dstp: the cpumask to set.
745 * Returns -errno, or 0 for success.
747 static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
749 return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits);
753 * cpulist_parse - extract a cpumask from a user string of ranges
754 * @buf: the buffer to extract from
755 * @dstp: the cpumask to set.
757 * Returns -errno, or 0 for success.
759 static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
761 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits);
765 * cpumask_size - size to allocate for a 'struct cpumask' in bytes
767 static inline unsigned int cpumask_size(void)
769 return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
773 * cpumask_var_t: struct cpumask for stack usage.
775 * Oh, the wicked games we play! In order to make kernel coding a
776 * little more difficult, we typedef cpumask_var_t to an array or a
777 * pointer: doing &mask on an array is a noop, so it still works.
780 * cpumask_var_t tmpmask;
781 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
784 * ... use 'tmpmask' like a normal struct cpumask * ...
786 * free_cpumask_var(tmpmask);
789 * However, one notable exception is there. alloc_cpumask_var() allocates
790 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has
791 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t.
793 * cpumask_var_t tmpmask;
794 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
799 * This code makes NR_CPUS length memcopy and brings to a memory corruption.
800 * cpumask_copy() provide safe copy functionality.
802 * Note that there is another evil here: If you define a cpumask_var_t
803 * as a percpu variable then the way to obtain the address of the cpumask
804 * structure differently influences what this_cpu_* operation needs to be
805 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use
806 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the
807 * other type of cpumask_var_t implementation is configured.
809 * Please also note that __cpumask_var_read_mostly can be used to declare
810 * a cpumask_var_t variable itself (not its content) as read mostly.
812 #ifdef CONFIG_CPUMASK_OFFSTACK
813 typedef struct cpumask *cpumask_var_t;
815 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
816 #define __cpumask_var_read_mostly __read_mostly
818 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
821 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
823 return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node);
827 * alloc_cpumask_var - allocate a struct cpumask
828 * @mask: pointer to cpumask_var_t where the cpumask is returned
831 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
832 * a nop returning a constant 1 (in <linux/cpumask.h>).
834 * See alloc_cpumask_var_node.
837 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
839 return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE);
843 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
845 return alloc_cpumask_var(mask, flags | __GFP_ZERO);
848 void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
849 void free_cpumask_var(cpumask_var_t mask);
850 void free_bootmem_cpumask_var(cpumask_var_t mask);
852 static inline bool cpumask_available(cpumask_var_t mask)
858 typedef struct cpumask cpumask_var_t[1];
860 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
861 #define __cpumask_var_read_mostly
863 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
868 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
874 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
876 cpumask_clear(*mask);
880 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
883 cpumask_clear(*mask);
887 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
891 static inline void free_cpumask_var(cpumask_var_t mask)
895 static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
899 static inline bool cpumask_available(cpumask_var_t mask)
903 #endif /* CONFIG_CPUMASK_OFFSTACK */
905 /* It's common to want to use cpu_all_mask in struct member initializers,
906 * so it has to refer to an address rather than a pointer. */
907 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
908 #define cpu_all_mask to_cpumask(cpu_all_bits)
910 /* First bits of cpu_bit_bitmap are in fact unset. */
911 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
914 /* Uniprocessor: the possible/online/present masks are always "1" */
915 #define for_each_possible_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
916 #define for_each_online_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
917 #define for_each_present_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
919 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
920 #define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask)
921 #define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask)
924 /* Wrappers for arch boot code to manipulate normally-constant masks */
925 void init_cpu_present(const struct cpumask *src);
926 void init_cpu_possible(const struct cpumask *src);
927 void init_cpu_online(const struct cpumask *src);
929 static inline void reset_cpu_possible_mask(void)
931 bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS);
935 set_cpu_possible(unsigned int cpu, bool possible)
938 cpumask_set_cpu(cpu, &__cpu_possible_mask);
940 cpumask_clear_cpu(cpu, &__cpu_possible_mask);
944 set_cpu_present(unsigned int cpu, bool present)
947 cpumask_set_cpu(cpu, &__cpu_present_mask);
949 cpumask_clear_cpu(cpu, &__cpu_present_mask);
952 void set_cpu_online(unsigned int cpu, bool online);
955 set_cpu_active(unsigned int cpu, bool active)
958 cpumask_set_cpu(cpu, &__cpu_active_mask);
960 cpumask_clear_cpu(cpu, &__cpu_active_mask);
964 set_cpu_dying(unsigned int cpu, bool dying)
967 cpumask_set_cpu(cpu, &__cpu_dying_mask);
969 cpumask_clear_cpu(cpu, &__cpu_dying_mask);
973 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
974 * @bitmap: the bitmap
976 * There are a few places where cpumask_var_t isn't appropriate and
977 * static cpumasks must be used (eg. very early boot), yet we don't
978 * expose the definition of 'struct cpumask'.
980 * This does the conversion, and can be used as a constant initializer.
982 #define to_cpumask(bitmap) \
983 ((struct cpumask *)(1 ? (bitmap) \
984 : (void *)sizeof(__check_is_bitmap(bitmap))))
986 static inline int __check_is_bitmap(const unsigned long *bitmap)
992 * Special-case data structure for "single bit set only" constant CPU masks.
994 * We pre-generate all the 64 (or 32) possible bit positions, with enough
995 * padding to the left and the right, and return the constant pointer
996 * appropriately offset.
998 extern const unsigned long
999 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
1001 static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
1003 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
1004 p -= cpu / BITS_PER_LONG;
1005 return to_cpumask(p);
1010 * num_online_cpus() - Read the number of online CPUs
1012 * Despite the fact that __num_online_cpus is of type atomic_t, this
1013 * interface gives only a momentary snapshot and is not protected against
1014 * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held
1017 static inline unsigned int num_online_cpus(void)
1019 return atomic_read(&__num_online_cpus);
1021 #define num_possible_cpus() cpumask_weight(cpu_possible_mask)
1022 #define num_present_cpus() cpumask_weight(cpu_present_mask)
1023 #define num_active_cpus() cpumask_weight(cpu_active_mask)
1025 static inline bool cpu_online(unsigned int cpu)
1027 return cpumask_test_cpu(cpu, cpu_online_mask);
1030 static inline bool cpu_possible(unsigned int cpu)
1032 return cpumask_test_cpu(cpu, cpu_possible_mask);
1035 static inline bool cpu_present(unsigned int cpu)
1037 return cpumask_test_cpu(cpu, cpu_present_mask);
1040 static inline bool cpu_active(unsigned int cpu)
1042 return cpumask_test_cpu(cpu, cpu_active_mask);
1045 static inline bool cpu_dying(unsigned int cpu)
1047 return cpumask_test_cpu(cpu, cpu_dying_mask);
1052 #define num_online_cpus() 1U
1053 #define num_possible_cpus() 1U
1054 #define num_present_cpus() 1U
1055 #define num_active_cpus() 1U
1057 static inline bool cpu_online(unsigned int cpu)
1062 static inline bool cpu_possible(unsigned int cpu)
1067 static inline bool cpu_present(unsigned int cpu)
1072 static inline bool cpu_active(unsigned int cpu)
1077 static inline bool cpu_dying(unsigned int cpu)
1082 #endif /* NR_CPUS > 1 */
1084 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))
1086 #if NR_CPUS <= BITS_PER_LONG
1087 #define CPU_BITS_ALL \
1089 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1092 #else /* NR_CPUS > BITS_PER_LONG */
1094 #define CPU_BITS_ALL \
1096 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
1097 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1099 #endif /* NR_CPUS > BITS_PER_LONG */
1102 * cpumap_print_to_pagebuf - copies the cpumask into the buffer either
1103 * as comma-separated list of cpus or hex values of cpumask
1104 * @list: indicates whether the cpumap must be list
1105 * @mask: the cpumask to copy
1106 * @buf: the buffer to copy into
1108 * Returns the length of the (null-terminated) @buf string, zero if
1109 * nothing is copied.
1111 static inline ssize_t
1112 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
1114 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
1119 * cpumap_print_bitmask_to_buf - copies the cpumask into the buffer as
1120 * hex values of cpumask
1122 * @buf: the buffer to copy into
1123 * @mask: the cpumask to copy
1124 * @off: in the string from which we are copying, we copy to @buf
1125 * @count: the maximum number of bytes to print
1127 * The function prints the cpumask into the buffer as hex values of
1128 * cpumask; Typically used by bin_attribute to export cpumask bitmask
1131 * Returns the length of how many bytes have been copied, excluding
1134 static inline ssize_t
1135 cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask,
1136 loff_t off, size_t count)
1138 return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask),
1139 nr_cpu_ids, off, count) - 1;
1143 * cpumap_print_list_to_buf - copies the cpumask into the buffer as
1144 * comma-separated list of cpus
1146 * Everything is same with the above cpumap_print_bitmask_to_buf()
1147 * except the print format.
1149 static inline ssize_t
1150 cpumap_print_list_to_buf(char *buf, const struct cpumask *mask,
1151 loff_t off, size_t count)
1153 return bitmap_print_list_to_buf(buf, cpumask_bits(mask),
1154 nr_cpu_ids, off, count) - 1;
1157 #if NR_CPUS <= BITS_PER_LONG
1158 #define CPU_MASK_ALL \
1160 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1163 #define CPU_MASK_ALL \
1165 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
1166 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1168 #endif /* NR_CPUS > BITS_PER_LONG */
1170 #define CPU_MASK_NONE \
1172 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
1175 #define CPU_MASK_CPU0 \
1181 * Provide a valid theoretical max size for cpumap and cpulist sysfs files
1182 * to avoid breaking userspace which may allocate a buffer based on the size
1183 * reported by e.g. fstat.
1185 * for cpumap NR_CPUS * 9/32 - 1 should be an exact length.
1187 * For cpulist 7 is (ceil(log10(NR_CPUS)) + 1) allowing for NR_CPUS to be up
1188 * to 2 orders of magnitude larger than 8192. And then we divide by 2 to
1189 * cover a worst-case of every other cpu being on one of two nodes for a
1190 * very large NR_CPUS.
1192 * Use PAGE_SIZE as a minimum for smaller configurations while avoiding
1193 * unsigned comparison to -1.
1195 #define CPUMAP_FILE_MAX_BYTES (((NR_CPUS * 9)/32 > PAGE_SIZE) \
1196 ? (NR_CPUS * 9)/32 - 1 : PAGE_SIZE)
1197 #define CPULIST_FILE_MAX_BYTES (((NR_CPUS * 7)/2 > PAGE_SIZE) ? (NR_CPUS * 7)/2 : PAGE_SIZE)
1199 #endif /* __LINUX_CPUMASK_H */