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>
16 /* Don't assign or return these: may not be this big! */
17 typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
20 * cpumask_bits - get the bits in a cpumask
21 * @maskp: the struct cpumask *
23 * You should only assume nr_cpu_ids bits of this mask are valid. This is
24 * a macro so it's const-correct.
26 #define cpumask_bits(maskp) ((maskp)->bits)
29 * cpumask_pr_args - printf args to output a cpumask
30 * @maskp: cpumask to be printed
32 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
34 #define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp)
39 extern unsigned int nr_cpu_ids;
42 #ifdef CONFIG_CPUMASK_OFFSTACK
43 /* Assuming NR_CPUS is huge, a runtime limit is more efficient. Also,
44 * not all bits may be allocated. */
45 #define nr_cpumask_bits nr_cpu_ids
47 #define nr_cpumask_bits ((unsigned int)NR_CPUS)
51 * The following particular system cpumasks and operations manage
52 * possible, present, active and online cpus.
54 * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
55 * cpu_present_mask - has bit 'cpu' set iff cpu is populated
56 * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler
57 * cpu_active_mask - has bit 'cpu' set iff cpu available to migration
59 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
61 * The cpu_possible_mask is fixed at boot time, as the set of CPU id's
62 * that it is possible might ever be plugged in at anytime during the
63 * life of that system boot. The cpu_present_mask is dynamic(*),
64 * representing which CPUs are currently plugged in. And
65 * cpu_online_mask is the dynamic subset of cpu_present_mask,
66 * indicating those CPUs available for scheduling.
68 * If HOTPLUG is enabled, then cpu_possible_mask is forced to have
69 * all NR_CPUS bits set, otherwise it is just the set of CPUs that
70 * ACPI reports present at boot.
72 * If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
73 * depending on what ACPI reports as currently plugged in, otherwise
74 * cpu_present_mask is just a copy of cpu_possible_mask.
76 * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not
77 * hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
80 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
81 * assumption that their single CPU is online. The UP
82 * cpu_{online,possible,present}_masks are placebos. Changing them
83 * will have no useful affect on the following num_*_cpus()
84 * and cpu_*() macros in the UP case. This ugliness is a UP
85 * optimization - don't waste any instructions or memory references
86 * asking if you're online or how many CPUs there are if there is
90 extern struct cpumask __cpu_possible_mask;
91 extern struct cpumask __cpu_online_mask;
92 extern struct cpumask __cpu_present_mask;
93 extern struct cpumask __cpu_active_mask;
94 extern struct cpumask __cpu_dying_mask;
95 #define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask)
96 #define cpu_online_mask ((const struct cpumask *)&__cpu_online_mask)
97 #define cpu_present_mask ((const struct cpumask *)&__cpu_present_mask)
98 #define cpu_active_mask ((const struct cpumask *)&__cpu_active_mask)
99 #define cpu_dying_mask ((const struct cpumask *)&__cpu_dying_mask)
101 extern atomic_t __num_online_cpus;
103 extern cpumask_t cpus_booted_once_mask;
105 static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits)
107 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
108 WARN_ON_ONCE(cpu >= bits);
109 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
112 /* verify cpu argument to cpumask_* operators */
113 static __always_inline unsigned int cpumask_check(unsigned int cpu)
115 cpu_max_bits_warn(cpu, nr_cpumask_bits);
120 * cpumask_first - get the first cpu in a cpumask
121 * @srcp: the cpumask pointer
123 * Returns >= nr_cpu_ids if no cpus set.
125 static inline unsigned int cpumask_first(const struct cpumask *srcp)
127 return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
131 * cpumask_first_zero - get the first unset cpu in a cpumask
132 * @srcp: the cpumask pointer
134 * Returns >= nr_cpu_ids if all cpus are set.
136 static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
138 return find_first_zero_bit(cpumask_bits(srcp), nr_cpumask_bits);
142 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
143 * @src1p: the first input
144 * @src2p: the second input
146 * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
149 unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
151 return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), nr_cpumask_bits);
155 * cpumask_last - get the last CPU in a cpumask
156 * @srcp: - the cpumask pointer
158 * Returns >= nr_cpumask_bits if no CPUs set.
160 static inline unsigned int cpumask_last(const struct cpumask *srcp)
162 return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits);
165 unsigned int __pure cpumask_next(int n, const struct cpumask *srcp);
168 * cpumask_next_zero - get the next unset 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 unset.
174 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
176 /* -1 is a legal arg here. */
179 return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
182 int __pure cpumask_next_and(int n, const struct cpumask *, const struct cpumask *);
183 int __pure cpumask_any_but(const struct cpumask *mask, unsigned int cpu);
186 /* Uniprocessor: there is only one valid CPU */
187 static inline unsigned int cpumask_local_spread(unsigned int i, int node)
192 static inline int cpumask_any_and_distribute(const struct cpumask *src1p,
193 const struct cpumask *src2p) {
194 return cpumask_first_and(src1p, src2p);
197 static inline int cpumask_any_distribute(const struct cpumask *srcp)
199 return cpumask_first(srcp);
202 unsigned int cpumask_local_spread(unsigned int i, int node);
203 int cpumask_any_and_distribute(const struct cpumask *src1p,
204 const struct cpumask *src2p);
205 int cpumask_any_distribute(const struct cpumask *srcp);
209 * for_each_cpu - iterate over every cpu in a mask
210 * @cpu: the (optionally unsigned) integer iterator
211 * @mask: the cpumask pointer
213 * After the loop, cpu is >= nr_cpu_ids.
215 #define for_each_cpu(cpu, mask) \
217 (cpu) = cpumask_next((cpu), (mask)), \
221 * for_each_cpu_not - iterate over every cpu in a complemented mask
222 * @cpu: the (optionally unsigned) integer iterator
223 * @mask: the cpumask pointer
225 * After the loop, cpu is >= nr_cpu_ids.
227 #define for_each_cpu_not(cpu, mask) \
229 (cpu) = cpumask_next_zero((cpu), (mask)), \
232 extern int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap);
235 * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location
236 * @cpu: the (optionally unsigned) integer iterator
237 * @mask: the cpumask pointer
238 * @start: the start location
240 * The implementation does not assume any bit in @mask is set (including @start).
242 * After the loop, cpu is >= nr_cpu_ids.
244 #define for_each_cpu_wrap(cpu, mask, start) \
245 for ((cpu) = cpumask_next_wrap((start)-1, (mask), (start), false); \
246 (cpu) < nr_cpumask_bits; \
247 (cpu) = cpumask_next_wrap((cpu), (mask), (start), true))
250 * for_each_cpu_and - iterate over every cpu in both masks
251 * @cpu: the (optionally unsigned) integer iterator
252 * @mask1: the first cpumask pointer
253 * @mask2: the second cpumask pointer
255 * This saves a temporary CPU mask in many places. It is equivalent to:
256 * struct cpumask tmp;
257 * cpumask_and(&tmp, &mask1, &mask2);
258 * for_each_cpu(cpu, &tmp)
261 * After the loop, cpu is >= nr_cpu_ids.
263 #define for_each_cpu_and(cpu, mask1, mask2) \
265 (cpu) = cpumask_next_and((cpu), (mask1), (mask2)), \
268 #define CPU_BITS_NONE \
270 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
273 #define CPU_BITS_CPU0 \
279 * cpumask_set_cpu - set a cpu in a cpumask
280 * @cpu: cpu number (< nr_cpu_ids)
281 * @dstp: the cpumask pointer
283 static __always_inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
285 set_bit(cpumask_check(cpu), cpumask_bits(dstp));
288 static __always_inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
290 __set_bit(cpumask_check(cpu), cpumask_bits(dstp));
295 * cpumask_clear_cpu - clear a cpu in a cpumask
296 * @cpu: cpu number (< nr_cpu_ids)
297 * @dstp: the cpumask pointer
299 static __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
301 clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
304 static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp)
306 __clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
310 * cpumask_test_cpu - test for a cpu in a cpumask
311 * @cpu: cpu number (< nr_cpu_ids)
312 * @cpumask: the cpumask pointer
314 * Returns 1 if @cpu is set in @cpumask, else returns 0
316 static __always_inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
318 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
322 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
323 * @cpu: cpu number (< nr_cpu_ids)
324 * @cpumask: the cpumask pointer
326 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
328 * test_and_set_bit wrapper for cpumasks.
330 static __always_inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
332 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
336 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
337 * @cpu: cpu number (< nr_cpu_ids)
338 * @cpumask: the cpumask pointer
340 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
342 * test_and_clear_bit wrapper for cpumasks.
344 static __always_inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
346 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
350 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
351 * @dstp: the cpumask pointer
353 static inline void cpumask_setall(struct cpumask *dstp)
355 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
359 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
360 * @dstp: the cpumask pointer
362 static inline void cpumask_clear(struct cpumask *dstp)
364 bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits);
368 * cpumask_and - *dstp = *src1p & *src2p
369 * @dstp: the cpumask result
370 * @src1p: the first input
371 * @src2p: the second input
373 * If *@dstp is empty, returns 0, else returns 1
375 static inline int cpumask_and(struct cpumask *dstp,
376 const struct cpumask *src1p,
377 const struct cpumask *src2p)
379 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
380 cpumask_bits(src2p), nr_cpumask_bits);
384 * cpumask_or - *dstp = *src1p | *src2p
385 * @dstp: the cpumask result
386 * @src1p: the first input
387 * @src2p: the second input
389 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
390 const struct cpumask *src2p)
392 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
393 cpumask_bits(src2p), nr_cpumask_bits);
397 * cpumask_xor - *dstp = *src1p ^ *src2p
398 * @dstp: the cpumask result
399 * @src1p: the first input
400 * @src2p: the second input
402 static inline void cpumask_xor(struct cpumask *dstp,
403 const struct cpumask *src1p,
404 const struct cpumask *src2p)
406 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
407 cpumask_bits(src2p), nr_cpumask_bits);
411 * cpumask_andnot - *dstp = *src1p & ~*src2p
412 * @dstp: the cpumask result
413 * @src1p: the first input
414 * @src2p: the second input
416 * If *@dstp is empty, returns 0, else returns 1
418 static inline int cpumask_andnot(struct cpumask *dstp,
419 const struct cpumask *src1p,
420 const struct cpumask *src2p)
422 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
423 cpumask_bits(src2p), nr_cpumask_bits);
427 * cpumask_complement - *dstp = ~*srcp
428 * @dstp: the cpumask result
429 * @srcp: the input to invert
431 static inline void cpumask_complement(struct cpumask *dstp,
432 const struct cpumask *srcp)
434 bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp),
439 * cpumask_equal - *src1p == *src2p
440 * @src1p: the first input
441 * @src2p: the second input
443 static inline bool cpumask_equal(const struct cpumask *src1p,
444 const struct cpumask *src2p)
446 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
451 * cpumask_or_equal - *src1p | *src2p == *src3p
452 * @src1p: the first input
453 * @src2p: the second input
454 * @src3p: the third input
456 static inline bool cpumask_or_equal(const struct cpumask *src1p,
457 const struct cpumask *src2p,
458 const struct cpumask *src3p)
460 return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p),
461 cpumask_bits(src3p), nr_cpumask_bits);
465 * cpumask_intersects - (*src1p & *src2p) != 0
466 * @src1p: the first input
467 * @src2p: the second input
469 static inline bool cpumask_intersects(const struct cpumask *src1p,
470 const struct cpumask *src2p)
472 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
477 * cpumask_subset - (*src1p & ~*src2p) == 0
478 * @src1p: the first input
479 * @src2p: the second input
481 * Returns 1 if *@src1p is a subset of *@src2p, else returns 0
483 static inline int cpumask_subset(const struct cpumask *src1p,
484 const struct cpumask *src2p)
486 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
491 * cpumask_empty - *srcp == 0
492 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
494 static inline bool cpumask_empty(const struct cpumask *srcp)
496 return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits);
500 * cpumask_full - *srcp == 0xFFFFFFFF...
501 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
503 static inline bool cpumask_full(const struct cpumask *srcp)
505 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
509 * cpumask_weight - Count of bits in *srcp
510 * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
512 static inline unsigned int cpumask_weight(const struct cpumask *srcp)
514 return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits);
518 * cpumask_shift_right - *dstp = *srcp >> n
519 * @dstp: the cpumask result
520 * @srcp: the input to shift
521 * @n: the number of bits to shift by
523 static inline void cpumask_shift_right(struct cpumask *dstp,
524 const struct cpumask *srcp, int n)
526 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
531 * cpumask_shift_left - *dstp = *srcp << n
532 * @dstp: the cpumask result
533 * @srcp: the input to shift
534 * @n: the number of bits to shift by
536 static inline void cpumask_shift_left(struct cpumask *dstp,
537 const struct cpumask *srcp, int n)
539 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
544 * cpumask_copy - *dstp = *srcp
546 * @srcp: the input cpumask
548 static inline void cpumask_copy(struct cpumask *dstp,
549 const struct cpumask *srcp)
551 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits);
555 * cpumask_any - pick a "random" cpu from *srcp
556 * @srcp: the input cpumask
558 * Returns >= nr_cpu_ids if no cpus set.
560 #define cpumask_any(srcp) cpumask_first(srcp)
563 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
564 * @mask1: the first input cpumask
565 * @mask2: the second input cpumask
567 * Returns >= nr_cpu_ids if no cpus set.
569 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
572 * cpumask_of - the cpumask containing just a given cpu
573 * @cpu: the cpu (<= nr_cpu_ids)
575 #define cpumask_of(cpu) (get_cpu_mask(cpu))
578 * cpumask_parse_user - extract a cpumask from a user string
579 * @buf: the buffer to extract from
580 * @len: the length of the buffer
581 * @dstp: the cpumask to set.
583 * Returns -errno, or 0 for success.
585 static inline int cpumask_parse_user(const char __user *buf, int len,
586 struct cpumask *dstp)
588 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
592 * cpumask_parselist_user - extract a cpumask from a user string
593 * @buf: the buffer to extract from
594 * @len: the length of the buffer
595 * @dstp: the cpumask to set.
597 * Returns -errno, or 0 for success.
599 static inline int cpumask_parselist_user(const char __user *buf, int len,
600 struct cpumask *dstp)
602 return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
607 * cpumask_parse - extract a cpumask from a string
608 * @buf: the buffer to extract from
609 * @dstp: the cpumask to set.
611 * Returns -errno, or 0 for success.
613 static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
615 return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits);
619 * cpulist_parse - extract a cpumask from a user string of ranges
620 * @buf: the buffer to extract from
621 * @dstp: the cpumask to set.
623 * Returns -errno, or 0 for success.
625 static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
627 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits);
631 * cpumask_size - size to allocate for a 'struct cpumask' in bytes
633 static inline unsigned int cpumask_size(void)
635 return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
639 * cpumask_var_t: struct cpumask for stack usage.
641 * Oh, the wicked games we play! In order to make kernel coding a
642 * little more difficult, we typedef cpumask_var_t to an array or a
643 * pointer: doing &mask on an array is a noop, so it still works.
646 * cpumask_var_t tmpmask;
647 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
650 * ... use 'tmpmask' like a normal struct cpumask * ...
652 * free_cpumask_var(tmpmask);
655 * However, one notable exception is there. alloc_cpumask_var() allocates
656 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has
657 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t.
659 * cpumask_var_t tmpmask;
660 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
665 * This code makes NR_CPUS length memcopy and brings to a memory corruption.
666 * cpumask_copy() provide safe copy functionality.
668 * Note that there is another evil here: If you define a cpumask_var_t
669 * as a percpu variable then the way to obtain the address of the cpumask
670 * structure differently influences what this_cpu_* operation needs to be
671 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use
672 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the
673 * other type of cpumask_var_t implementation is configured.
675 * Please also note that __cpumask_var_read_mostly can be used to declare
676 * a cpumask_var_t variable itself (not its content) as read mostly.
678 #ifdef CONFIG_CPUMASK_OFFSTACK
679 typedef struct cpumask *cpumask_var_t;
681 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
682 #define __cpumask_var_read_mostly __read_mostly
684 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
685 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
686 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
687 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
688 void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
689 void free_cpumask_var(cpumask_var_t mask);
690 void free_bootmem_cpumask_var(cpumask_var_t mask);
692 static inline bool cpumask_available(cpumask_var_t mask)
698 typedef struct cpumask cpumask_var_t[1];
700 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
701 #define __cpumask_var_read_mostly
703 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
708 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
714 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
716 cpumask_clear(*mask);
720 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
723 cpumask_clear(*mask);
727 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
731 static inline void free_cpumask_var(cpumask_var_t mask)
735 static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
739 static inline bool cpumask_available(cpumask_var_t mask)
743 #endif /* CONFIG_CPUMASK_OFFSTACK */
745 /* It's common to want to use cpu_all_mask in struct member initializers,
746 * so it has to refer to an address rather than a pointer. */
747 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
748 #define cpu_all_mask to_cpumask(cpu_all_bits)
750 /* First bits of cpu_bit_bitmap are in fact unset. */
751 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
754 /* Uniprocessor: the possible/online/present masks are always "1" */
755 #define for_each_possible_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
756 #define for_each_online_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
757 #define for_each_present_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++)
759 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
760 #define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask)
761 #define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask)
764 /* Wrappers for arch boot code to manipulate normally-constant masks */
765 void init_cpu_present(const struct cpumask *src);
766 void init_cpu_possible(const struct cpumask *src);
767 void init_cpu_online(const struct cpumask *src);
769 static inline void reset_cpu_possible_mask(void)
771 bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS);
775 set_cpu_possible(unsigned int cpu, bool possible)
778 cpumask_set_cpu(cpu, &__cpu_possible_mask);
780 cpumask_clear_cpu(cpu, &__cpu_possible_mask);
784 set_cpu_present(unsigned int cpu, bool present)
787 cpumask_set_cpu(cpu, &__cpu_present_mask);
789 cpumask_clear_cpu(cpu, &__cpu_present_mask);
792 void set_cpu_online(unsigned int cpu, bool online);
795 set_cpu_active(unsigned int cpu, bool active)
798 cpumask_set_cpu(cpu, &__cpu_active_mask);
800 cpumask_clear_cpu(cpu, &__cpu_active_mask);
804 set_cpu_dying(unsigned int cpu, bool dying)
807 cpumask_set_cpu(cpu, &__cpu_dying_mask);
809 cpumask_clear_cpu(cpu, &__cpu_dying_mask);
813 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
814 * @bitmap: the bitmap
816 * There are a few places where cpumask_var_t isn't appropriate and
817 * static cpumasks must be used (eg. very early boot), yet we don't
818 * expose the definition of 'struct cpumask'.
820 * This does the conversion, and can be used as a constant initializer.
822 #define to_cpumask(bitmap) \
823 ((struct cpumask *)(1 ? (bitmap) \
824 : (void *)sizeof(__check_is_bitmap(bitmap))))
826 static inline int __check_is_bitmap(const unsigned long *bitmap)
832 * Special-case data structure for "single bit set only" constant CPU masks.
834 * We pre-generate all the 64 (or 32) possible bit positions, with enough
835 * padding to the left and the right, and return the constant pointer
836 * appropriately offset.
838 extern const unsigned long
839 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
841 static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
843 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
844 p -= cpu / BITS_PER_LONG;
845 return to_cpumask(p);
850 * num_online_cpus() - Read the number of online CPUs
852 * Despite the fact that __num_online_cpus is of type atomic_t, this
853 * interface gives only a momentary snapshot and is not protected against
854 * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held
857 static inline unsigned int num_online_cpus(void)
859 return atomic_read(&__num_online_cpus);
861 #define num_possible_cpus() cpumask_weight(cpu_possible_mask)
862 #define num_present_cpus() cpumask_weight(cpu_present_mask)
863 #define num_active_cpus() cpumask_weight(cpu_active_mask)
865 static inline bool cpu_online(unsigned int cpu)
867 return cpumask_test_cpu(cpu, cpu_online_mask);
870 static inline bool cpu_possible(unsigned int cpu)
872 return cpumask_test_cpu(cpu, cpu_possible_mask);
875 static inline bool cpu_present(unsigned int cpu)
877 return cpumask_test_cpu(cpu, cpu_present_mask);
880 static inline bool cpu_active(unsigned int cpu)
882 return cpumask_test_cpu(cpu, cpu_active_mask);
885 static inline bool cpu_dying(unsigned int cpu)
887 return cpumask_test_cpu(cpu, cpu_dying_mask);
892 #define num_online_cpus() 1U
893 #define num_possible_cpus() 1U
894 #define num_present_cpus() 1U
895 #define num_active_cpus() 1U
897 static inline bool cpu_online(unsigned int cpu)
902 static inline bool cpu_possible(unsigned int cpu)
907 static inline bool cpu_present(unsigned int cpu)
912 static inline bool cpu_active(unsigned int cpu)
917 static inline bool cpu_dying(unsigned int cpu)
922 #endif /* NR_CPUS > 1 */
924 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))
926 #if NR_CPUS <= BITS_PER_LONG
927 #define CPU_BITS_ALL \
929 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
932 #else /* NR_CPUS > BITS_PER_LONG */
934 #define CPU_BITS_ALL \
936 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
937 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
939 #endif /* NR_CPUS > BITS_PER_LONG */
942 * cpumap_print_to_pagebuf - copies the cpumask into the buffer either
943 * as comma-separated list of cpus or hex values of cpumask
944 * @list: indicates whether the cpumap must be list
945 * @mask: the cpumask to copy
946 * @buf: the buffer to copy into
948 * Returns the length of the (null-terminated) @buf string, zero if
951 static inline ssize_t
952 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
954 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
959 * cpumap_print_bitmask_to_buf - copies the cpumask into the buffer as
960 * hex values of cpumask
962 * @buf: the buffer to copy into
963 * @mask: the cpumask to copy
964 * @off: in the string from which we are copying, we copy to @buf
965 * @count: the maximum number of bytes to print
967 * The function prints the cpumask into the buffer as hex values of
968 * cpumask; Typically used by bin_attribute to export cpumask bitmask
971 * Returns the length of how many bytes have been copied, excluding
974 static inline ssize_t
975 cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask,
976 loff_t off, size_t count)
978 return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask),
979 nr_cpu_ids, off, count) - 1;
983 * cpumap_print_list_to_buf - copies the cpumask into the buffer as
984 * comma-separated list of cpus
986 * Everything is same with the above cpumap_print_bitmask_to_buf()
987 * except the print format.
989 static inline ssize_t
990 cpumap_print_list_to_buf(char *buf, const struct cpumask *mask,
991 loff_t off, size_t count)
993 return bitmap_print_list_to_buf(buf, cpumask_bits(mask),
994 nr_cpu_ids, off, count) - 1;
997 #if NR_CPUS <= BITS_PER_LONG
998 #define CPU_MASK_ALL \
1000 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1003 #define CPU_MASK_ALL \
1005 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
1006 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
1008 #endif /* NR_CPUS > BITS_PER_LONG */
1010 #define CPU_MASK_NONE \
1012 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
1015 #define CPU_MASK_CPU0 \
1020 #endif /* __LINUX_CPUMASK_H */