xref: /linux/include/linux/cpumask.h (revision ba220b42c05561761b764089b27a34fd2c6cdc19)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_CPUMASK_H
3 #define __LINUX_CPUMASK_H
4 
5 /*
6  * Cpumasks provide a bitmap suitable for representing the
7  * set of CPUs in a system, one bit position per CPU number.  In general,
8  * only nr_cpu_ids (<= NR_CPUS) bits are valid.
9  */
10 #include <linux/atomic.h>
11 #include <linux/bitmap.h>
12 #include <linux/cleanup.h>
13 #include <linux/cpumask_types.h>
14 #include <linux/gfp_types.h>
15 #include <linux/numa.h>
16 #include <linux/sprintf.h>
17 #include <linux/threads.h>
18 #include <linux/types.h>
19 #include <vdso/page.h>
20 
21 #include <asm/bug.h>
22 
23 /**
24  * cpumask_pr_args - printf args to output a cpumask
25  * @maskp: cpumask to be printed
26  *
27  * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
28  */
29 #define cpumask_pr_args(maskp)		nr_cpu_ids, cpumask_bits(maskp)
30 
31 #if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
32 #define nr_cpu_ids ((unsigned int)NR_CPUS)
33 #else
34 extern unsigned int nr_cpu_ids;
35 #endif
36 
37 static __always_inline void set_nr_cpu_ids(unsigned int nr)
38 {
39 #if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
40 	WARN_ON(nr != nr_cpu_ids);
41 #else
42 	nr_cpu_ids = nr;
43 #endif
44 }
45 
46 /*
47  * We have several different "preferred sizes" for the cpumask
48  * operations, depending on operation.
49  *
50  * For example, the bitmap scanning and operating operations have
51  * optimized routines that work for the single-word case, but only when
52  * the size is constant. So if NR_CPUS fits in one single word, we are
53  * better off using that small constant, in order to trigger the
54  * optimized bit finding. That is 'small_cpumask_size'.
55  *
56  * The clearing and copying operations will similarly perform better
57  * with a constant size, but we limit that size arbitrarily to four
58  * words. We call this 'large_cpumask_size'.
59  *
60  * Finally, some operations just want the exact limit, either because
61  * they set bits or just don't have any faster fixed-sized versions. We
62  * call this just 'nr_cpumask_bits'.
63  *
64  * Note that these optional constants are always guaranteed to be at
65  * least as big as 'nr_cpu_ids' itself is, and all our cpumask
66  * allocations are at least that size (see cpumask_size()). The
67  * optimization comes from being able to potentially use a compile-time
68  * constant instead of a run-time generated exact number of CPUs.
69  */
70 #if NR_CPUS <= BITS_PER_LONG
71   #define small_cpumask_bits ((unsigned int)NR_CPUS)
72   #define large_cpumask_bits ((unsigned int)NR_CPUS)
73 #elif NR_CPUS <= 4*BITS_PER_LONG
74   #define small_cpumask_bits nr_cpu_ids
75   #define large_cpumask_bits ((unsigned int)NR_CPUS)
76 #else
77   #define small_cpumask_bits nr_cpu_ids
78   #define large_cpumask_bits nr_cpu_ids
79 #endif
80 #define nr_cpumask_bits nr_cpu_ids
81 
82 /*
83  * The following particular system cpumasks and operations manage
84  * possible, present, active and online cpus.
85  *
86  *     cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
87  *     cpu_present_mask - has bit 'cpu' set iff cpu is populated
88  *     cpu_enabled_mask - has bit 'cpu' set iff cpu can be brought online
89  *     cpu_online_mask  - has bit 'cpu' set iff cpu available to scheduler
90  *     cpu_active_mask  - has bit 'cpu' set iff cpu available to migration
91  *
92  *  If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
93  *
94  *  The cpu_possible_mask is fixed at boot time, as the set of CPU IDs
95  *  that it is possible might ever be plugged in at anytime during the
96  *  life of that system boot.  The cpu_present_mask is dynamic(*),
97  *  representing which CPUs are currently plugged in.  And
98  *  cpu_online_mask is the dynamic subset of cpu_present_mask,
99  *  indicating those CPUs available for scheduling.
100  *
101  *  If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
102  *  depending on what ACPI reports as currently plugged in, otherwise
103  *  cpu_present_mask is just a copy of cpu_possible_mask.
104  *
105  *  (*) Well, cpu_present_mask is dynamic in the hotplug case.  If not
106  *      hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
107  *
108  * Subtleties:
109  * 1) UP ARCHes (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
110  *    assumption that their single CPU is online.  The UP
111  *    cpu_{online,possible,present}_masks are placebos.  Changing them
112  *    will have no useful affect on the following num_*_cpus()
113  *    and cpu_*() macros in the UP case.  This ugliness is a UP
114  *    optimization - don't waste any instructions or memory references
115  *    asking if you're online or how many CPUs there are if there is
116  *    only one CPU.
117  */
118 
119 extern struct cpumask __cpu_possible_mask;
120 extern struct cpumask __cpu_online_mask;
121 extern struct cpumask __cpu_enabled_mask;
122 extern struct cpumask __cpu_present_mask;
123 extern struct cpumask __cpu_active_mask;
124 extern struct cpumask __cpu_dying_mask;
125 #define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask)
126 #define cpu_online_mask   ((const struct cpumask *)&__cpu_online_mask)
127 #define cpu_enabled_mask   ((const struct cpumask *)&__cpu_enabled_mask)
128 #define cpu_present_mask  ((const struct cpumask *)&__cpu_present_mask)
129 #define cpu_active_mask   ((const struct cpumask *)&__cpu_active_mask)
130 #define cpu_dying_mask    ((const struct cpumask *)&__cpu_dying_mask)
131 
132 extern atomic_t __num_online_cpus;
133 extern unsigned int __num_possible_cpus;
134 
135 extern cpumask_t cpus_booted_once_mask;
136 
137 static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits)
138 {
139 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
140 	WARN_ON_ONCE(cpu >= bits);
141 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
142 }
143 
144 /* verify cpu argument to cpumask_* operators */
145 static __always_inline unsigned int cpumask_check(unsigned int cpu)
146 {
147 	cpu_max_bits_warn(cpu, small_cpumask_bits);
148 	return cpu;
149 }
150 
151 /**
152  * cpumask_first - get the first cpu in a cpumask
153  * @srcp: the cpumask pointer
154  *
155  * Return: >= nr_cpu_ids if no cpus set.
156  */
157 static __always_inline unsigned int cpumask_first(const struct cpumask *srcp)
158 {
159 	return find_first_bit(cpumask_bits(srcp), small_cpumask_bits);
160 }
161 
162 /**
163  * cpumask_first_zero - get the first unset cpu in a cpumask
164  * @srcp: the cpumask pointer
165  *
166  * Return: >= nr_cpu_ids if all cpus are set.
167  */
168 static __always_inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
169 {
170 	return find_first_zero_bit(cpumask_bits(srcp), small_cpumask_bits);
171 }
172 
173 /**
174  * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
175  * @srcp1: the first input
176  * @srcp2: the second input
177  *
178  * Return: >= nr_cpu_ids if no cpus set in both.  See also cpumask_next_and().
179  */
180 static __always_inline
181 unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
182 {
183 	return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
184 }
185 
186 /**
187  * cpumask_first_andnot - return the first cpu from *srcp1 & ~*srcp2
188  * @srcp1: the first input
189  * @srcp2: the second input
190  *
191  * Return: >= nr_cpu_ids if no such cpu found.
192  */
193 static __always_inline
194 unsigned int cpumask_first_andnot(const struct cpumask *srcp1, const struct cpumask *srcp2)
195 {
196 	return find_first_andnot_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
197 }
198 
199 /**
200  * cpumask_first_and_and - return the first cpu from *srcp1 & *srcp2 & *srcp3
201  * @srcp1: the first input
202  * @srcp2: the second input
203  * @srcp3: the third input
204  *
205  * Return: >= nr_cpu_ids if no cpus set in all.
206  */
207 static __always_inline
208 unsigned int cpumask_first_and_and(const struct cpumask *srcp1,
209 				   const struct cpumask *srcp2,
210 				   const struct cpumask *srcp3)
211 {
212 	return find_first_and_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
213 				      cpumask_bits(srcp3), small_cpumask_bits);
214 }
215 
216 /**
217  * cpumask_last - get the last CPU in a cpumask
218  * @srcp:	- the cpumask pointer
219  *
220  * Return:	>= nr_cpumask_bits if no CPUs set.
221  */
222 static __always_inline unsigned int cpumask_last(const struct cpumask *srcp)
223 {
224 	return find_last_bit(cpumask_bits(srcp), small_cpumask_bits);
225 }
226 
227 /**
228  * cpumask_next - get the next cpu in a cpumask
229  * @n: the cpu prior to the place to search (i.e. return will be > @n)
230  * @srcp: the cpumask pointer
231  *
232  * Return: >= nr_cpu_ids if no further cpus set.
233  */
234 static __always_inline
235 unsigned int cpumask_next(int n, const struct cpumask *srcp)
236 {
237 	/* -1 is a legal arg here. */
238 	if (n != -1)
239 		cpumask_check(n);
240 	return find_next_bit(cpumask_bits(srcp), small_cpumask_bits, n + 1);
241 }
242 
243 /**
244  * cpumask_next_zero - get the next unset cpu in a cpumask
245  * @n: the cpu prior to the place to search (i.e. return will be > @n)
246  * @srcp: the cpumask pointer
247  *
248  * Return: >= nr_cpu_ids if no further cpus unset.
249  */
250 static __always_inline
251 unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
252 {
253 	/* -1 is a legal arg here. */
254 	if (n != -1)
255 		cpumask_check(n);
256 	return find_next_zero_bit(cpumask_bits(srcp), small_cpumask_bits, n+1);
257 }
258 
259 #if NR_CPUS == 1
260 /* Uniprocessor: there is only one valid CPU */
261 static __always_inline
262 unsigned int cpumask_local_spread(unsigned int i, int node)
263 {
264 	return 0;
265 }
266 
267 static __always_inline
268 unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
269 					const struct cpumask *src2p)
270 {
271 	return cpumask_first_and(src1p, src2p);
272 }
273 
274 static __always_inline
275 unsigned int cpumask_any_distribute(const struct cpumask *srcp)
276 {
277 	return cpumask_first(srcp);
278 }
279 #else
280 unsigned int cpumask_local_spread(unsigned int i, int node);
281 unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
282 			       const struct cpumask *src2p);
283 unsigned int cpumask_any_distribute(const struct cpumask *srcp);
284 #endif /* NR_CPUS */
285 
286 /**
287  * cpumask_next_and - get the next cpu in *src1p & *src2p
288  * @n: the cpu prior to the place to search (i.e. return will be > @n)
289  * @src1p: the first cpumask pointer
290  * @src2p: the second cpumask pointer
291  *
292  * Return: >= nr_cpu_ids if no further cpus set in both.
293  */
294 static __always_inline
295 unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
296 			      const struct cpumask *src2p)
297 {
298 	/* -1 is a legal arg here. */
299 	if (n != -1)
300 		cpumask_check(n);
301 	return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p),
302 		small_cpumask_bits, n + 1);
303 }
304 
305 /**
306  * cpumask_next_andnot - get the next cpu in *src1p & ~*src2p
307  * @n: the cpu prior to the place to search (i.e. return will be > @n)
308  * @src1p: the first cpumask pointer
309  * @src2p: the second cpumask pointer
310  *
311  * Return: >= nr_cpu_ids if no further cpus set in both.
312  */
313 static __always_inline
314 unsigned int cpumask_next_andnot(int n, const struct cpumask *src1p,
315 				 const struct cpumask *src2p)
316 {
317 	/* -1 is a legal arg here. */
318 	if (n != -1)
319 		cpumask_check(n);
320 	return find_next_andnot_bit(cpumask_bits(src1p), cpumask_bits(src2p),
321 		small_cpumask_bits, n + 1);
322 }
323 
324 /**
325  * cpumask_next_and_wrap - get the next cpu in *src1p & *src2p, starting from
326  *			   @n+1. If nothing found, wrap around and start from
327  *			   the beginning
328  * @n: the cpu prior to the place to search (i.e. search starts from @n+1)
329  * @src1p: the first cpumask pointer
330  * @src2p: the second cpumask pointer
331  *
332  * Return: next set bit, wrapped if needed, or >= nr_cpu_ids if @src1p & @src2p is empty.
333  */
334 static __always_inline
335 unsigned int cpumask_next_and_wrap(int n, const struct cpumask *src1p,
336 			      const struct cpumask *src2p)
337 {
338 	/* -1 is a legal arg here. */
339 	if (n != -1)
340 		cpumask_check(n);
341 	return find_next_and_bit_wrap(cpumask_bits(src1p), cpumask_bits(src2p),
342 		small_cpumask_bits, n + 1);
343 }
344 
345 /**
346  * cpumask_next_wrap - get the next cpu in *src, starting from @n+1. If nothing
347  *		       found, wrap around and start from the beginning
348  * @n: the cpu prior to the place to search (i.e. search starts from @n+1)
349  * @src: cpumask pointer
350  *
351  * Return: next set bit, wrapped if needed, or >= nr_cpu_ids if @src is empty.
352  */
353 static __always_inline
354 unsigned int cpumask_next_wrap(int n, const struct cpumask *src)
355 {
356 	/* -1 is a legal arg here. */
357 	if (n != -1)
358 		cpumask_check(n);
359 	return find_next_bit_wrap(cpumask_bits(src), small_cpumask_bits, n + 1);
360 }
361 
362 /**
363  * cpumask_random - get random cpu in *src.
364  * @src: cpumask pointer
365  *
366  * Return: random set bit, or >= nr_cpu_ids if @src is empty.
367  */
368 static __always_inline
369 unsigned int cpumask_random(const struct cpumask *src)
370 {
371 	return find_random_bit(cpumask_bits(src), nr_cpu_ids);
372 }
373 
374 /**
375  * for_each_cpu - iterate over every cpu in a mask
376  * @cpu: the (optionally unsigned) integer iterator
377  * @mask: the cpumask pointer
378  *
379  * After the loop, cpu is >= nr_cpu_ids.
380  */
381 #define for_each_cpu(cpu, mask)				\
382 	for_each_set_bit(cpu, cpumask_bits(mask), small_cpumask_bits)
383 
384 /**
385  * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location
386  * @cpu: the (optionally unsigned) integer iterator
387  * @mask: the cpumask pointer
388  * @start: the start location
389  *
390  * The implementation does not assume any bit in @mask is set (including @start).
391  *
392  * After the loop, cpu is >= nr_cpu_ids.
393  */
394 #define for_each_cpu_wrap(cpu, mask, start)				\
395 	for_each_set_bit_wrap(cpu, cpumask_bits(mask), small_cpumask_bits, start)
396 
397 /**
398  * for_each_cpu_and - iterate over every cpu in both masks
399  * @cpu: the (optionally unsigned) integer iterator
400  * @mask1: the first cpumask pointer
401  * @mask2: the second cpumask pointer
402  *
403  * This saves a temporary CPU mask in many places.  It is equivalent to:
404  *	struct cpumask tmp;
405  *	cpumask_and(&tmp, &mask1, &mask2);
406  *	for_each_cpu(cpu, &tmp)
407  *		...
408  *
409  * After the loop, cpu is >= nr_cpu_ids.
410  */
411 #define for_each_cpu_and(cpu, mask1, mask2)				\
412 	for_each_and_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
413 
414 /**
415  * for_each_cpu_andnot - iterate over every cpu present in one mask, excluding
416  *			 those present in another.
417  * @cpu: the (optionally unsigned) integer iterator
418  * @mask1: the first cpumask pointer
419  * @mask2: the second cpumask pointer
420  *
421  * This saves a temporary CPU mask in many places.  It is equivalent to:
422  *	struct cpumask tmp;
423  *	cpumask_andnot(&tmp, &mask1, &mask2);
424  *	for_each_cpu(cpu, &tmp)
425  *		...
426  *
427  * After the loop, cpu is >= nr_cpu_ids.
428  */
429 #define for_each_cpu_andnot(cpu, mask1, mask2)				\
430 	for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
431 
432 /**
433  * for_each_cpu_or - iterate over every cpu present in either mask
434  * @cpu: the (optionally unsigned) integer iterator
435  * @mask1: the first cpumask pointer
436  * @mask2: the second cpumask pointer
437  *
438  * This saves a temporary CPU mask in many places.  It is equivalent to:
439  *	struct cpumask tmp;
440  *	cpumask_or(&tmp, &mask1, &mask2);
441  *	for_each_cpu(cpu, &tmp)
442  *		...
443  *
444  * After the loop, cpu is >= nr_cpu_ids.
445  */
446 #define for_each_cpu_or(cpu, mask1, mask2)				\
447 	for_each_or_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
448 
449 /**
450  * for_each_cpu_from - iterate over CPUs present in @mask, from @cpu to the end of @mask.
451  * @cpu: the (optionally unsigned) integer iterator
452  * @mask: the cpumask pointer
453  *
454  * After the loop, cpu is >= nr_cpu_ids.
455  */
456 #define for_each_cpu_from(cpu, mask)				\
457 	for_each_set_bit_from(cpu, cpumask_bits(mask), small_cpumask_bits)
458 
459 /**
460  * cpumask_any_but - return an arbitrary cpu in a cpumask, but not this one.
461  * @mask: the cpumask to search
462  * @cpu: the cpu to ignore.
463  *
464  * Often used to find any cpu but smp_processor_id() in a mask.
465  * If @cpu == -1, the function is equivalent to cpumask_any().
466  * Return: >= nr_cpu_ids if no cpus set.
467  */
468 static __always_inline
469 unsigned int cpumask_any_but(const struct cpumask *mask, int cpu)
470 {
471 	unsigned int i;
472 
473 	/* -1 is a legal arg here. */
474 	if (cpu != -1)
475 		cpumask_check(cpu);
476 
477 	for_each_cpu(i, mask)
478 		if (i != cpu)
479 			break;
480 	return i;
481 }
482 
483 /**
484  * cpumask_any_and_but - pick an arbitrary cpu from *mask1 & *mask2, but not this one.
485  * @mask1: the first input cpumask
486  * @mask2: the second input cpumask
487  * @cpu: the cpu to ignore
488  *
489  * If @cpu == -1, the function is equivalent to cpumask_any_and().
490  * Returns >= nr_cpu_ids if no cpus set.
491  */
492 static __always_inline
493 unsigned int cpumask_any_and_but(const struct cpumask *mask1,
494 				 const struct cpumask *mask2,
495 				 int cpu)
496 {
497 	unsigned int i;
498 
499 	/* -1 is a legal arg here. */
500 	if (cpu != -1)
501 		cpumask_check(cpu);
502 
503 	i = cpumask_first_and(mask1, mask2);
504 	if (i != cpu)
505 		return i;
506 
507 	return cpumask_next_and(cpu, mask1, mask2);
508 }
509 
510 /**
511  * cpumask_any_andnot_but - pick an arbitrary cpu from *mask1 & ~*mask2, but not this one.
512  * @mask1: the first input cpumask
513  * @mask2: the second input cpumask
514  * @cpu: the cpu to ignore
515  *
516  * If @cpu == -1, the function returns the first matching cpu.
517  * Returns >= nr_cpu_ids if no cpus set.
518  */
519 static __always_inline
520 unsigned int cpumask_any_andnot_but(const struct cpumask *mask1,
521 				    const struct cpumask *mask2,
522 				    int cpu)
523 {
524 	unsigned int i;
525 
526 	/* -1 is a legal arg here. */
527 	if (cpu != -1)
528 		cpumask_check(cpu);
529 
530 	i = cpumask_first_andnot(mask1, mask2);
531 	if (i != cpu)
532 		return i;
533 
534 	return cpumask_next_andnot(cpu, mask1, mask2);
535 }
536 
537 /**
538  * cpumask_nth - get the Nth cpu in a cpumask
539  * @srcp: the cpumask pointer
540  * @cpu: the Nth cpu to find, starting from 0
541  *
542  * Return: >= nr_cpu_ids if such cpu doesn't exist.
543  */
544 static __always_inline
545 unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp)
546 {
547 	return find_nth_bit(cpumask_bits(srcp), small_cpumask_bits, cpumask_check(cpu));
548 }
549 
550 /**
551  * cpumask_nth_and - get the Nth cpu in 2 cpumasks
552  * @srcp1: the cpumask pointer
553  * @srcp2: the cpumask pointer
554  * @cpu: the Nth cpu to find, starting from 0
555  *
556  * Return: >= nr_cpu_ids if such cpu doesn't exist.
557  */
558 static __always_inline
559 unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1,
560 							const struct cpumask *srcp2)
561 {
562 	return find_nth_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
563 				small_cpumask_bits, cpumask_check(cpu));
564 }
565 
566 /**
567  * cpumask_nth_and_andnot - get the Nth cpu set in 1st and 2nd cpumask, and clear in 3rd.
568  * @srcp1: the cpumask pointer
569  * @srcp2: the cpumask pointer
570  * @srcp3: the cpumask pointer
571  * @cpu: the Nth cpu to find, starting from 0
572  *
573  * Return: >= nr_cpu_ids if such cpu doesn't exist.
574  */
575 static __always_inline
576 unsigned int cpumask_nth_and_andnot(unsigned int cpu, const struct cpumask *srcp1,
577 							const struct cpumask *srcp2,
578 							const struct cpumask *srcp3)
579 {
580 	return find_nth_and_andnot_bit(cpumask_bits(srcp1),
581 					cpumask_bits(srcp2),
582 					cpumask_bits(srcp3),
583 					small_cpumask_bits, cpumask_check(cpu));
584 }
585 
586 #define CPU_BITS_NONE						\
587 {								\
588 	[0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL			\
589 }
590 
591 #define CPU_BITS_CPU0						\
592 {								\
593 	[0] =  1UL						\
594 }
595 
596 /**
597  * cpumask_set_cpu - set a cpu in a cpumask
598  * @cpu: cpu number (< nr_cpu_ids)
599  * @dstp: the cpumask pointer
600  */
601 static __always_inline
602 void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
603 {
604 	set_bit(cpumask_check(cpu), cpumask_bits(dstp));
605 }
606 
607 static __always_inline
608 void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
609 {
610 	__set_bit(cpumask_check(cpu), cpumask_bits(dstp));
611 }
612 
613 /**
614  * cpumask_clear_cpus - clear cpus in a cpumask
615  * @dstp:  the cpumask pointer
616  * @cpu:   cpu number (< nr_cpu_ids)
617  * @ncpus: number of cpus to clear (< nr_cpu_ids)
618  */
619 static __always_inline void cpumask_clear_cpus(struct cpumask *dstp,
620 						unsigned int cpu, unsigned int ncpus)
621 {
622 	cpumask_check(cpu + ncpus - 1);
623 	bitmap_clear(cpumask_bits(dstp), cpumask_check(cpu), ncpus);
624 }
625 
626 /**
627  * cpumask_clear_cpu - clear a cpu in a cpumask
628  * @cpu: cpu number (< nr_cpu_ids)
629  * @dstp: the cpumask pointer
630  */
631 static __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
632 {
633 	clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
634 }
635 
636 static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp)
637 {
638 	__clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
639 }
640 
641 /**
642  * cpumask_test_cpu - test for a cpu in a cpumask
643  * @cpu: cpu number (< nr_cpu_ids)
644  * @cpumask: the cpumask pointer
645  *
646  * Return: true if @cpu is set in @cpumask, else returns false
647  */
648 static __always_inline
649 bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
650 {
651 	return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
652 }
653 
654 /**
655  * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
656  * @cpu: cpu number (< nr_cpu_ids)
657  * @cpumask: the cpumask pointer
658  *
659  * test_and_set_bit wrapper for cpumasks.
660  *
661  * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
662  */
663 static __always_inline
664 bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
665 {
666 	return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
667 }
668 
669 /**
670  * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
671  * @cpu: cpu number (< nr_cpu_ids)
672  * @cpumask: the cpumask pointer
673  *
674  * test_and_clear_bit wrapper for cpumasks.
675  *
676  * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
677  */
678 static __always_inline
679 bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
680 {
681 	return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
682 }
683 
684 /**
685  * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
686  * @dstp: the cpumask pointer
687  */
688 static __always_inline void cpumask_setall(struct cpumask *dstp)
689 {
690 	if (small_const_nbits(small_cpumask_bits)) {
691 		cpumask_bits(dstp)[0] = BITMAP_LAST_WORD_MASK(nr_cpumask_bits);
692 		return;
693 	}
694 	bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
695 }
696 
697 /**
698  * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
699  * @dstp: the cpumask pointer
700  */
701 static __always_inline void cpumask_clear(struct cpumask *dstp)
702 {
703 	bitmap_zero(cpumask_bits(dstp), large_cpumask_bits);
704 }
705 
706 /**
707  * cpumask_and - *dstp = *src1p & *src2p
708  * @dstp: the cpumask result
709  * @src1p: the first input
710  * @src2p: the second input
711  *
712  * Return: false if *@dstp is empty, else returns true
713  */
714 static __always_inline
715 bool cpumask_and(struct cpumask *dstp, const struct cpumask *src1p,
716 		 const struct cpumask *src2p)
717 {
718 	return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
719 				       cpumask_bits(src2p), small_cpumask_bits);
720 }
721 
722 /**
723  * cpumask_or - *dstp = *src1p | *src2p
724  * @dstp: the cpumask result
725  * @src1p: the first input
726  * @src2p: the second input
727  */
728 static __always_inline
729 void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
730 		const struct cpumask *src2p)
731 {
732 	bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
733 				      cpumask_bits(src2p), small_cpumask_bits);
734 }
735 
736 /**
737  * cpumask_weighted_or - *dstp = *src1p | *src2p and return the weight of the result
738  * @dstp: the cpumask result
739  * @src1p: the first input
740  * @src2p: the second input
741  *
742  * Return: The number of bits set in the resulting cpumask @dstp
743  */
744 static __always_inline
745 unsigned int cpumask_weighted_or(struct cpumask *dstp, const struct cpumask *src1p,
746 				 const struct cpumask *src2p)
747 {
748 	return bitmap_weighted_or(cpumask_bits(dstp), cpumask_bits(src1p),
749 				  cpumask_bits(src2p), small_cpumask_bits);
750 }
751 
752 /**
753  * cpumask_xor - *dstp = *src1p ^ *src2p
754  * @dstp: the cpumask result
755  * @src1p: the first input
756  * @src2p: the second input
757  */
758 static __always_inline
759 void cpumask_xor(struct cpumask *dstp, const struct cpumask *src1p,
760 		 const struct cpumask *src2p)
761 {
762 	bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
763 				       cpumask_bits(src2p), small_cpumask_bits);
764 }
765 
766 /**
767  * cpumask_andnot - *dstp = *src1p & ~*src2p
768  * @dstp: the cpumask result
769  * @src1p: the first input
770  * @src2p: the second input
771  *
772  * Return: false if *@dstp is empty, else returns true
773  */
774 static __always_inline
775 bool cpumask_andnot(struct cpumask *dstp, const struct cpumask *src1p,
776 		    const struct cpumask *src2p)
777 {
778 	return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
779 					  cpumask_bits(src2p), small_cpumask_bits);
780 }
781 
782 /**
783  * cpumask_equal - *src1p == *src2p
784  * @src1p: the first input
785  * @src2p: the second input
786  *
787  * Return: true if the cpumasks are equal, false if not
788  */
789 static __always_inline
790 bool cpumask_equal(const struct cpumask *src1p, const struct cpumask *src2p)
791 {
792 	return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
793 						 small_cpumask_bits);
794 }
795 
796 /**
797  * cpumask_or_equal - *src1p | *src2p == *src3p
798  * @src1p: the first input
799  * @src2p: the second input
800  * @src3p: the third input
801  *
802  * Return: true if first cpumask ORed with second cpumask == third cpumask,
803  *	   otherwise false
804  */
805 static __always_inline
806 bool cpumask_or_equal(const struct cpumask *src1p, const struct cpumask *src2p,
807 		      const struct cpumask *src3p)
808 {
809 	return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p),
810 			       cpumask_bits(src3p), small_cpumask_bits);
811 }
812 
813 /**
814  * cpumask_intersects - (*src1p & *src2p) != 0
815  * @src1p: the first input
816  * @src2p: the second input
817  *
818  * Return: true if first cpumask ANDed with second cpumask is non-empty,
819  *	   otherwise false
820  */
821 static __always_inline
822 bool cpumask_intersects(const struct cpumask *src1p, const struct cpumask *src2p)
823 {
824 	return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
825 						      small_cpumask_bits);
826 }
827 
828 /**
829  * cpumask_subset - (*src1p & ~*src2p) == 0
830  * @src1p: the first input
831  * @src2p: the second input
832  *
833  * Return: true if *@src1p is a subset of *@src2p, else returns false
834  */
835 static __always_inline
836 bool cpumask_subset(const struct cpumask *src1p, const struct cpumask *src2p)
837 {
838 	return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
839 						  small_cpumask_bits);
840 }
841 
842 /**
843  * cpumask_empty - *srcp == 0
844  * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
845  *
846  * Return: true if srcp is empty (has no bits set), else false
847  */
848 static __always_inline bool cpumask_empty(const struct cpumask *srcp)
849 {
850 	return bitmap_empty(cpumask_bits(srcp), small_cpumask_bits);
851 }
852 
853 /**
854  * cpumask_full - *srcp == 0xFFFFFFFF...
855  * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
856  *
857  * Return: true if srcp is full (has all bits set), else false
858  */
859 static __always_inline bool cpumask_full(const struct cpumask *srcp)
860 {
861 	return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
862 }
863 
864 /**
865  * cpumask_weight - Count of bits in *srcp
866  * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
867  *
868  * Return: count of bits set in *srcp
869  */
870 static __always_inline unsigned int cpumask_weight(const struct cpumask *srcp)
871 {
872 	return bitmap_weight(cpumask_bits(srcp), small_cpumask_bits);
873 }
874 
875 /**
876  * cpumask_weight_and - Count of bits in (*srcp1 & *srcp2)
877  * @srcp1: the cpumask to count bits (< nr_cpu_ids) in.
878  * @srcp2: the cpumask to count bits (< nr_cpu_ids) in.
879  *
880  * Return: count of bits set in both *srcp1 and *srcp2
881  */
882 static __always_inline
883 unsigned int cpumask_weight_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
884 {
885 	return bitmap_weight_and(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
886 }
887 
888 /**
889  * cpumask_weight_andnot - Count of bits in (*srcp1 & ~*srcp2)
890  * @srcp1: the cpumask to count bits (< nr_cpu_ids) in.
891  * @srcp2: the cpumask to count bits (< nr_cpu_ids) in.
892  *
893  * Return: count of bits set in both *srcp1 and *srcp2
894  */
895 static __always_inline
896 unsigned int cpumask_weight_andnot(const struct cpumask *srcp1,
897 				   const struct cpumask *srcp2)
898 {
899 	return bitmap_weight_andnot(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
900 }
901 
902 /**
903  * cpumask_shift_right - *dstp = *srcp >> n
904  * @dstp: the cpumask result
905  * @srcp: the input to shift
906  * @n: the number of bits to shift by
907  */
908 static __always_inline
909 void cpumask_shift_right(struct cpumask *dstp, const struct cpumask *srcp, int n)
910 {
911 	bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
912 					       small_cpumask_bits);
913 }
914 
915 /**
916  * cpumask_shift_left - *dstp = *srcp << n
917  * @dstp: the cpumask result
918  * @srcp: the input to shift
919  * @n: the number of bits to shift by
920  */
921 static __always_inline
922 void cpumask_shift_left(struct cpumask *dstp, const struct cpumask *srcp, int n)
923 {
924 	bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
925 					      nr_cpumask_bits);
926 }
927 
928 /**
929  * cpumask_copy - *dstp = *srcp
930  * @dstp: the result
931  * @srcp: the input cpumask
932  */
933 static __always_inline
934 void cpumask_copy(struct cpumask *dstp, const struct cpumask *srcp)
935 {
936 	bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), large_cpumask_bits);
937 }
938 
939 /**
940  * cpumask_any - pick an arbitrary cpu from *srcp
941  * @srcp: the input cpumask
942  *
943  * Return: >= nr_cpu_ids if no cpus set.
944  */
945 #define cpumask_any(srcp) cpumask_first(srcp)
946 
947 /**
948  * cpumask_any_and - pick an arbitrary cpu from *mask1 & *mask2
949  * @mask1: the first input cpumask
950  * @mask2: the second input cpumask
951  *
952  * Return: >= nr_cpu_ids if no cpus set.
953  */
954 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
955 
956 /**
957  * cpumask_of - the cpumask containing just a given cpu
958  * @cpu: the cpu (<= nr_cpu_ids)
959  */
960 #define cpumask_of(cpu) (get_cpu_mask(cpu))
961 
962 /**
963  * cpumask_parse_user - extract a cpumask from a user string
964  * @buf: the buffer to extract from
965  * @len: the length of the buffer
966  * @dstp: the cpumask to set.
967  *
968  * Return: -errno, or 0 for success.
969  */
970 static __always_inline
971 int cpumask_parse_user(const char __user *buf, int len, struct cpumask *dstp)
972 {
973 	return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
974 }
975 
976 /**
977  * cpumask_parselist_user - extract a cpumask from a user string
978  * @buf: the buffer to extract from
979  * @len: the length of the buffer
980  * @dstp: the cpumask to set.
981  *
982  * Return: -errno, or 0 for success.
983  */
984 static __always_inline
985 int cpumask_parselist_user(const char __user *buf, int len, struct cpumask *dstp)
986 {
987 	return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
988 				     nr_cpumask_bits);
989 }
990 
991 /**
992  * cpumask_parse - extract a cpumask from a string
993  * @buf: the buffer to extract from
994  * @dstp: the cpumask to set.
995  *
996  * Return: -errno, or 0 for success.
997  */
998 static __always_inline int cpumask_parse(const char *buf, struct cpumask *dstp)
999 {
1000 	return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits);
1001 }
1002 
1003 /**
1004  * cpulist_parse - extract a cpumask from a user string of ranges
1005  * @buf: the buffer to extract from
1006  * @dstp: the cpumask to set.
1007  *
1008  * Return: -errno, or 0 for success.
1009  */
1010 static __always_inline int cpulist_parse(const char *buf, struct cpumask *dstp)
1011 {
1012 	return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits);
1013 }
1014 
1015 /**
1016  * cpumask_size - calculate size to allocate for a 'struct cpumask' in bytes
1017  *
1018  * Return: size to allocate for a &struct cpumask in bytes
1019  */
1020 static __always_inline unsigned int cpumask_size(void)
1021 {
1022 	return bitmap_size(large_cpumask_bits);
1023 }
1024 
1025 #ifdef CONFIG_CPUMASK_OFFSTACK
1026 
1027 #define this_cpu_cpumask_var_ptr(x)	this_cpu_read(x)
1028 #define __cpumask_var_read_mostly	__read_mostly
1029 #define CPUMASK_VAR_NULL		NULL
1030 
1031 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
1032 
1033 static __always_inline
1034 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
1035 {
1036 	return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node);
1037 }
1038 
1039 /**
1040  * alloc_cpumask_var - allocate a struct cpumask
1041  * @mask: pointer to cpumask_var_t where the cpumask is returned
1042  * @flags: GFP_ flags
1043  *
1044  * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
1045  * a nop returning a constant 1 (in <linux/cpumask.h>).
1046  *
1047  * See alloc_cpumask_var_node.
1048  *
1049  * Return: %true if allocation succeeded, %false if not
1050  */
1051 static __always_inline
1052 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
1053 {
1054 	return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE);
1055 }
1056 
1057 static __always_inline
1058 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
1059 {
1060 	return alloc_cpumask_var(mask, flags | __GFP_ZERO);
1061 }
1062 
1063 void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
1064 void free_cpumask_var(cpumask_var_t mask);
1065 void free_bootmem_cpumask_var(cpumask_var_t mask);
1066 
1067 static __always_inline bool cpumask_available(cpumask_var_t mask)
1068 {
1069 	return mask != NULL;
1070 }
1071 
1072 #else
1073 
1074 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
1075 #define __cpumask_var_read_mostly
1076 #define CPUMASK_VAR_NULL {}
1077 
1078 static __always_inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
1079 {
1080 	return true;
1081 }
1082 
1083 static __always_inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
1084 					  int node)
1085 {
1086 	return true;
1087 }
1088 
1089 static __always_inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
1090 {
1091 	cpumask_clear(*mask);
1092 	return true;
1093 }
1094 
1095 static __always_inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
1096 					  int node)
1097 {
1098 	cpumask_clear(*mask);
1099 	return true;
1100 }
1101 
1102 static __always_inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
1103 {
1104 }
1105 
1106 static __always_inline void free_cpumask_var(cpumask_var_t mask)
1107 {
1108 }
1109 
1110 static __always_inline void free_bootmem_cpumask_var(cpumask_var_t mask)
1111 {
1112 }
1113 
1114 static __always_inline bool cpumask_available(cpumask_var_t mask)
1115 {
1116 	return true;
1117 }
1118 #endif /* CONFIG_CPUMASK_OFFSTACK */
1119 
1120 DEFINE_FREE(free_cpumask_var, struct cpumask *, if (_T) free_cpumask_var(_T));
1121 
1122 /* It's common to want to use cpu_all_mask in struct member initializers,
1123  * so it has to refer to an address rather than a pointer. */
1124 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
1125 #define cpu_all_mask to_cpumask(cpu_all_bits)
1126 
1127 /* First bits of cpu_bit_bitmap are in fact unset. */
1128 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
1129 
1130 #if NR_CPUS == 1
1131 /* Uniprocessor: the possible/online/present masks are always "1" */
1132 #define for_each_possible_cpu(cpu)	for ((cpu) = 0; (cpu) < 1; (cpu)++)
1133 #define for_each_online_cpu(cpu)	for ((cpu) = 0; (cpu) < 1; (cpu)++)
1134 #define for_each_present_cpu(cpu)	for ((cpu) = 0; (cpu) < 1; (cpu)++)
1135 
1136 #define for_each_possible_cpu_wrap(cpu, start)	\
1137 	for ((void)(start), (cpu) = 0; (cpu) < 1; (cpu)++)
1138 #define for_each_online_cpu_wrap(cpu, start)	\
1139 	for ((void)(start), (cpu) = 0; (cpu) < 1; (cpu)++)
1140 #else
1141 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
1142 #define for_each_online_cpu(cpu)   for_each_cpu((cpu), cpu_online_mask)
1143 #define for_each_enabled_cpu(cpu)   for_each_cpu((cpu), cpu_enabled_mask)
1144 #define for_each_present_cpu(cpu)  for_each_cpu((cpu), cpu_present_mask)
1145 
1146 #define for_each_possible_cpu_wrap(cpu, start)	\
1147 	for_each_cpu_wrap((cpu), cpu_possible_mask, (start))
1148 #define for_each_online_cpu_wrap(cpu, start)	\
1149 	for_each_cpu_wrap((cpu), cpu_online_mask, (start))
1150 #endif
1151 
1152 /* Wrappers for arch boot code to manipulate normally-constant masks */
1153 void init_cpu_present(const struct cpumask *src);
1154 void init_cpu_possible(const struct cpumask *src);
1155 
1156 #define assign_cpu(cpu, mask, val)	\
1157 	assign_bit(cpumask_check(cpu), cpumask_bits(mask), (val))
1158 
1159 #define __assign_cpu(cpu, mask, val)	\
1160 	__assign_bit(cpumask_check(cpu), cpumask_bits(mask), (val))
1161 
1162 #define set_cpu_enabled(cpu, enabled)	assign_cpu((cpu), &__cpu_enabled_mask, (enabled))
1163 #define set_cpu_present(cpu, present)	assign_cpu((cpu), &__cpu_present_mask, (present))
1164 #define set_cpu_active(cpu, active)	assign_cpu((cpu), &__cpu_active_mask, (active))
1165 #define set_cpu_dying(cpu, dying)	assign_cpu((cpu), &__cpu_dying_mask, (dying))
1166 
1167 void set_cpu_online(unsigned int cpu, bool online);
1168 void set_cpu_possible(unsigned int cpu, bool possible);
1169 
1170 /**
1171  * to_cpumask - convert a NR_CPUS bitmap to a struct cpumask *
1172  * @bitmap: the bitmap
1173  *
1174  * There are a few places where cpumask_var_t isn't appropriate and
1175  * static cpumasks must be used (eg. very early boot), yet we don't
1176  * expose the definition of 'struct cpumask'.
1177  *
1178  * This does the conversion, and can be used as a constant initializer.
1179  */
1180 #define to_cpumask(bitmap)						\
1181 	((struct cpumask *)(1 ? (bitmap)				\
1182 			    : (void *)sizeof(__check_is_bitmap(bitmap))))
1183 
1184 static __always_inline int __check_is_bitmap(const unsigned long *bitmap)
1185 {
1186 	return 1;
1187 }
1188 
1189 /*
1190  * Special-case data structure for "single bit set only" constant CPU masks.
1191  *
1192  * We pre-generate all the 64 (or 32) possible bit positions, with enough
1193  * padding to the left and the right, and return the constant pointer
1194  * appropriately offset.
1195  */
1196 extern const unsigned long
1197 	cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
1198 
1199 static __always_inline const struct cpumask *get_cpu_mask(unsigned int cpu)
1200 {
1201 	const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
1202 	p -= cpu / BITS_PER_LONG;
1203 	return to_cpumask(p);
1204 }
1205 
1206 #if NR_CPUS > 1
1207 /**
1208  * num_online_cpus() - Read the number of online CPUs
1209  *
1210  * Despite the fact that __num_online_cpus is of type atomic_t, this
1211  * interface gives only a momentary snapshot and is not protected against
1212  * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held
1213  * region.
1214  *
1215  * Return: momentary snapshot of the number of online CPUs
1216  */
1217 static __always_inline unsigned int num_online_cpus(void)
1218 {
1219 	return raw_atomic_read(&__num_online_cpus);
1220 }
1221 
1222 static __always_inline unsigned int num_possible_cpus(void)
1223 {
1224 	return __num_possible_cpus;
1225 }
1226 
1227 #define num_enabled_cpus()	cpumask_weight(cpu_enabled_mask)
1228 #define num_present_cpus()	cpumask_weight(cpu_present_mask)
1229 #define num_active_cpus()	cpumask_weight(cpu_active_mask)
1230 
1231 static __always_inline bool cpu_online(unsigned int cpu)
1232 {
1233 	return cpumask_test_cpu(cpu, cpu_online_mask);
1234 }
1235 
1236 static __always_inline bool cpu_enabled(unsigned int cpu)
1237 {
1238 	return cpumask_test_cpu(cpu, cpu_enabled_mask);
1239 }
1240 
1241 static __always_inline bool cpu_possible(unsigned int cpu)
1242 {
1243 	return cpumask_test_cpu(cpu, cpu_possible_mask);
1244 }
1245 
1246 static __always_inline bool cpu_present(unsigned int cpu)
1247 {
1248 	return cpumask_test_cpu(cpu, cpu_present_mask);
1249 }
1250 
1251 static __always_inline bool cpu_active(unsigned int cpu)
1252 {
1253 	return cpumask_test_cpu(cpu, cpu_active_mask);
1254 }
1255 
1256 static __always_inline bool cpu_dying(unsigned int cpu)
1257 {
1258 	return cpumask_test_cpu(cpu, cpu_dying_mask);
1259 }
1260 
1261 #else
1262 
1263 #define num_online_cpus()	1U
1264 #define num_possible_cpus()	1U
1265 #define num_enabled_cpus()	1U
1266 #define num_present_cpus()	1U
1267 #define num_active_cpus()	1U
1268 
1269 static __always_inline bool cpu_online(unsigned int cpu)
1270 {
1271 	return cpu == 0;
1272 }
1273 
1274 static __always_inline bool cpu_possible(unsigned int cpu)
1275 {
1276 	return cpu == 0;
1277 }
1278 
1279 static __always_inline bool cpu_enabled(unsigned int cpu)
1280 {
1281 	return cpu == 0;
1282 }
1283 
1284 static __always_inline bool cpu_present(unsigned int cpu)
1285 {
1286 	return cpu == 0;
1287 }
1288 
1289 static __always_inline bool cpu_active(unsigned int cpu)
1290 {
1291 	return cpu == 0;
1292 }
1293 
1294 static __always_inline bool cpu_dying(unsigned int cpu)
1295 {
1296 	return false;
1297 }
1298 
1299 #endif /* NR_CPUS > 1 */
1300 
1301 #define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))
1302 
1303 #if NR_CPUS <= BITS_PER_LONG
1304 #define CPU_BITS_ALL						\
1305 {								\
1306 	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
1307 }
1308 
1309 #else /* NR_CPUS > BITS_PER_LONG */
1310 
1311 #define CPU_BITS_ALL						\
1312 {								\
1313 	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,		\
1314 	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
1315 }
1316 #endif /* NR_CPUS > BITS_PER_LONG */
1317 
1318 /**
1319  * cpumap_print_to_pagebuf  - copies the cpumask into the buffer either
1320  *	as comma-separated list of cpus or hex values of cpumask
1321  * @list: indicates whether the cpumap must be list
1322  * @mask: the cpumask to copy
1323  * @buf: the buffer to copy into
1324  *
1325  * Return: the length of the (null-terminated) @buf string, zero if
1326  * nothing is copied.
1327  */
1328 static __always_inline ssize_t
1329 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
1330 {
1331 	/* Opencode offset_in_page(buf) to not include linux/mm.h */
1332 	return scnprintf(buf, PAGE_SIZE - ((unsigned long)buf & ~PAGE_MASK),
1333 			 list ? "%*pbl\n" : "%*pb\n", cpumask_pr_args(mask));
1334 }
1335 
1336 /**
1337  * cpumap_print_bitmask_to_buf  - copies the cpumask into the buffer as
1338  *	hex values of cpumask
1339  *
1340  * @buf: the buffer to copy into
1341  * @mask: the cpumask to copy
1342  * @off: in the string from which we are copying, we copy to @buf
1343  * @count: the maximum number of bytes to print
1344  *
1345  * The function prints the cpumask into the buffer as hex values of
1346  * cpumask; Typically used by bin_attribute to export cpumask bitmask
1347  * ABI.
1348  *
1349  * Return: the length of how many bytes have been copied, excluding
1350  * terminating '\0'.
1351  */
1352 static __always_inline
1353 ssize_t cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask,
1354 				    loff_t off, size_t count)
1355 {
1356 	return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask),
1357 				   nr_cpu_ids, off, count) - 1;
1358 }
1359 
1360 /**
1361  * cpumap_print_list_to_buf  - copies the cpumask into the buffer as
1362  *	comma-separated list of cpus
1363  * @buf: the buffer to copy into
1364  * @mask: the cpumask to copy
1365  * @off: in the string from which we are copying, we copy to @buf
1366  * @count: the maximum number of bytes to print
1367  *
1368  * Everything is same with the above cpumap_print_bitmask_to_buf()
1369  * except the print format.
1370  *
1371  * Return: the length of how many bytes have been copied, excluding
1372  * terminating '\0'.
1373  */
1374 static __always_inline
1375 ssize_t cpumap_print_list_to_buf(char *buf, const struct cpumask *mask,
1376 				 loff_t off, size_t count)
1377 {
1378 	return bitmap_print_list_to_buf(buf, cpumask_bits(mask),
1379 				   nr_cpu_ids, off, count) - 1;
1380 }
1381 
1382 #if NR_CPUS <= BITS_PER_LONG
1383 #define CPU_MASK_ALL							\
1384 (cpumask_t) { {								\
1385 	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
1386 } }
1387 #else
1388 #define CPU_MASK_ALL							\
1389 (cpumask_t) { {								\
1390 	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,			\
1391 	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
1392 } }
1393 #endif /* NR_CPUS > BITS_PER_LONG */
1394 
1395 #define CPU_MASK_NONE							\
1396 (cpumask_t) { {								\
1397 	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  0UL				\
1398 } }
1399 
1400 #define CPU_MASK_CPU0							\
1401 (cpumask_t) { {								\
1402 	[0] =  1UL							\
1403 } }
1404 
1405 /*
1406  * Provide a valid theoretical max size for cpumap and cpulist sysfs files
1407  * to avoid breaking userspace which may allocate a buffer based on the size
1408  * reported by e.g. fstat.
1409  *
1410  * for cpumap NR_CPUS * 9/32 - 1 should be an exact length.
1411  *
1412  * For cpulist 7 is (ceil(log10(NR_CPUS)) + 1) allowing for NR_CPUS to be up
1413  * to 2 orders of magnitude larger than 8192. And then we divide by 2 to
1414  * cover a worst-case of every other cpu being on one of two nodes for a
1415  * very large NR_CPUS.
1416  *
1417  *  Use PAGE_SIZE as a minimum for smaller configurations while avoiding
1418  *  unsigned comparison to -1.
1419  */
1420 #define CPUMAP_FILE_MAX_BYTES  (((NR_CPUS * 9)/32 > PAGE_SIZE) \
1421 					? (NR_CPUS * 9)/32 - 1 : PAGE_SIZE)
1422 #define CPULIST_FILE_MAX_BYTES  (((NR_CPUS * 7)/2 > PAGE_SIZE) ? (NR_CPUS * 7)/2 : PAGE_SIZE)
1423 
1424 #endif /* __LINUX_CPUMASK_H */
1425