xref: /linux/include/linux/cpumask.h (revision f468cf53c5240bf5063d0c6fe620b5ae2de37801)
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/threads.h>
17 #include <linux/types.h>
18 
19 #include <asm/bug.h>
20 
21 /**
22  * cpumask_pr_args - printf args to output a cpumask
23  * @maskp: cpumask to be printed
24  *
25  * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
26  */
27 #define cpumask_pr_args(maskp)		nr_cpu_ids, cpumask_bits(maskp)
28 
29 #if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
30 #define nr_cpu_ids ((unsigned int)NR_CPUS)
31 #else
32 extern unsigned int nr_cpu_ids;
33 #endif
34 
set_nr_cpu_ids(unsigned int nr)35 static __always_inline void set_nr_cpu_ids(unsigned int nr)
36 {
37 #if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS)
38 	WARN_ON(nr != nr_cpu_ids);
39 #else
40 	nr_cpu_ids = nr;
41 #endif
42 }
43 
44 /*
45  * We have several different "preferred sizes" for the cpumask
46  * operations, depending on operation.
47  *
48  * For example, the bitmap scanning and operating operations have
49  * optimized routines that work for the single-word case, but only when
50  * the size is constant. So if NR_CPUS fits in one single word, we are
51  * better off using that small constant, in order to trigger the
52  * optimized bit finding. That is 'small_cpumask_size'.
53  *
54  * The clearing and copying operations will similarly perform better
55  * with a constant size, but we limit that size arbitrarily to four
56  * words. We call this 'large_cpumask_size'.
57  *
58  * Finally, some operations just want the exact limit, either because
59  * they set bits or just don't have any faster fixed-sized versions. We
60  * call this just 'nr_cpumask_bits'.
61  *
62  * Note that these optional constants are always guaranteed to be at
63  * least as big as 'nr_cpu_ids' itself is, and all our cpumask
64  * allocations are at least that size (see cpumask_size()). The
65  * optimization comes from being able to potentially use a compile-time
66  * constant instead of a run-time generated exact number of CPUs.
67  */
68 #if NR_CPUS <= BITS_PER_LONG
69   #define small_cpumask_bits ((unsigned int)NR_CPUS)
70   #define large_cpumask_bits ((unsigned int)NR_CPUS)
71 #elif NR_CPUS <= 4*BITS_PER_LONG
72   #define small_cpumask_bits nr_cpu_ids
73   #define large_cpumask_bits ((unsigned int)NR_CPUS)
74 #else
75   #define small_cpumask_bits nr_cpu_ids
76   #define large_cpumask_bits nr_cpu_ids
77 #endif
78 #define nr_cpumask_bits nr_cpu_ids
79 
80 /*
81  * The following particular system cpumasks and operations manage
82  * possible, present, active and online cpus.
83  *
84  *     cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
85  *     cpu_present_mask - has bit 'cpu' set iff cpu is populated
86  *     cpu_enabled_mask - has bit 'cpu' set iff cpu can be brought online
87  *     cpu_online_mask  - has bit 'cpu' set iff cpu available to scheduler
88  *     cpu_active_mask  - has bit 'cpu' set iff cpu available to migration
89  *
90  *  If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
91  *
92  *  The cpu_possible_mask is fixed at boot time, as the set of CPU IDs
93  *  that it is possible might ever be plugged in at anytime during the
94  *  life of that system boot.  The cpu_present_mask is dynamic(*),
95  *  representing which CPUs are currently plugged in.  And
96  *  cpu_online_mask is the dynamic subset of cpu_present_mask,
97  *  indicating those CPUs available for scheduling.
98  *
99  *  If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
100  *  depending on what ACPI reports as currently plugged in, otherwise
101  *  cpu_present_mask is just a copy of cpu_possible_mask.
102  *
103  *  (*) Well, cpu_present_mask is dynamic in the hotplug case.  If not
104  *      hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
105  *
106  * Subtleties:
107  * 1) UP ARCHes (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
108  *    assumption that their single CPU is online.  The UP
109  *    cpu_{online,possible,present}_masks are placebos.  Changing them
110  *    will have no useful affect on the following num_*_cpus()
111  *    and cpu_*() macros in the UP case.  This ugliness is a UP
112  *    optimization - don't waste any instructions or memory references
113  *    asking if you're online or how many CPUs there are if there is
114  *    only one CPU.
115  */
116 
117 extern struct cpumask __cpu_possible_mask;
118 extern struct cpumask __cpu_online_mask;
119 extern struct cpumask __cpu_enabled_mask;
120 extern struct cpumask __cpu_present_mask;
121 extern struct cpumask __cpu_active_mask;
122 extern struct cpumask __cpu_dying_mask;
123 #define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask)
124 #define cpu_online_mask   ((const struct cpumask *)&__cpu_online_mask)
125 #define cpu_enabled_mask   ((const struct cpumask *)&__cpu_enabled_mask)
126 #define cpu_present_mask  ((const struct cpumask *)&__cpu_present_mask)
127 #define cpu_active_mask   ((const struct cpumask *)&__cpu_active_mask)
128 #define cpu_dying_mask    ((const struct cpumask *)&__cpu_dying_mask)
129 
130 extern atomic_t __num_online_cpus;
131 extern unsigned int __num_possible_cpus;
132 
133 extern cpumask_t cpus_booted_once_mask;
134 
cpu_max_bits_warn(unsigned int cpu,unsigned int bits)135 static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits)
136 {
137 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
138 	WARN_ON_ONCE(cpu >= bits);
139 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
140 }
141 
142 /* verify cpu argument to cpumask_* operators */
cpumask_check(unsigned int cpu)143 static __always_inline unsigned int cpumask_check(unsigned int cpu)
144 {
145 	cpu_max_bits_warn(cpu, small_cpumask_bits);
146 	return cpu;
147 }
148 
149 /**
150  * cpumask_first - get the first cpu in a cpumask
151  * @srcp: the cpumask pointer
152  *
153  * Return: >= nr_cpu_ids if no cpus set.
154  */
cpumask_first(const struct cpumask * srcp)155 static __always_inline unsigned int cpumask_first(const struct cpumask *srcp)
156 {
157 	return find_first_bit(cpumask_bits(srcp), small_cpumask_bits);
158 }
159 
160 /**
161  * cpumask_first_zero - get the first unset cpu in a cpumask
162  * @srcp: the cpumask pointer
163  *
164  * Return: >= nr_cpu_ids if all cpus are set.
165  */
cpumask_first_zero(const struct cpumask * srcp)166 static __always_inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
167 {
168 	return find_first_zero_bit(cpumask_bits(srcp), small_cpumask_bits);
169 }
170 
171 /**
172  * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
173  * @srcp1: the first input
174  * @srcp2: the second input
175  *
176  * Return: >= nr_cpu_ids if no cpus set in both.  See also cpumask_next_and().
177  */
178 static __always_inline
cpumask_first_and(const struct cpumask * srcp1,const struct cpumask * srcp2)179 unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
180 {
181 	return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
182 }
183 
184 /**
185  * cpumask_first_andnot - return the first cpu from *srcp1 & ~*srcp2
186  * @srcp1: the first input
187  * @srcp2: the second input
188  *
189  * Return: >= nr_cpu_ids if no such cpu found.
190  */
191 static __always_inline
cpumask_first_andnot(const struct cpumask * srcp1,const struct cpumask * srcp2)192 unsigned int cpumask_first_andnot(const struct cpumask *srcp1, const struct cpumask *srcp2)
193 {
194 	return find_first_andnot_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
195 }
196 
197 /**
198  * cpumask_first_and_and - return the first cpu from *srcp1 & *srcp2 & *srcp3
199  * @srcp1: the first input
200  * @srcp2: the second input
201  * @srcp3: the third input
202  *
203  * Return: >= nr_cpu_ids if no cpus set in all.
204  */
205 static __always_inline
cpumask_first_and_and(const struct cpumask * srcp1,const struct cpumask * srcp2,const struct cpumask * srcp3)206 unsigned int cpumask_first_and_and(const struct cpumask *srcp1,
207 				   const struct cpumask *srcp2,
208 				   const struct cpumask *srcp3)
209 {
210 	return find_first_and_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
211 				      cpumask_bits(srcp3), small_cpumask_bits);
212 }
213 
214 /**
215  * cpumask_last - get the last CPU in a cpumask
216  * @srcp:	- the cpumask pointer
217  *
218  * Return:	>= nr_cpumask_bits if no CPUs set.
219  */
cpumask_last(const struct cpumask * srcp)220 static __always_inline unsigned int cpumask_last(const struct cpumask *srcp)
221 {
222 	return find_last_bit(cpumask_bits(srcp), small_cpumask_bits);
223 }
224 
225 /**
226  * cpumask_next - get the next cpu in a cpumask
227  * @n: the cpu prior to the place to search (i.e. return will be > @n)
228  * @srcp: the cpumask pointer
229  *
230  * Return: >= nr_cpu_ids if no further cpus set.
231  */
232 static __always_inline
cpumask_next(int n,const struct cpumask * srcp)233 unsigned int cpumask_next(int n, const struct cpumask *srcp)
234 {
235 	/* -1 is a legal arg here. */
236 	if (n != -1)
237 		cpumask_check(n);
238 	return find_next_bit(cpumask_bits(srcp), small_cpumask_bits, n + 1);
239 }
240 
241 /**
242  * cpumask_next_zero - get the next unset cpu in a cpumask
243  * @n: the cpu prior to the place to search (i.e. return will be > @n)
244  * @srcp: the cpumask pointer
245  *
246  * Return: >= nr_cpu_ids if no further cpus unset.
247  */
248 static __always_inline
cpumask_next_zero(int n,const struct cpumask * srcp)249 unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
250 {
251 	/* -1 is a legal arg here. */
252 	if (n != -1)
253 		cpumask_check(n);
254 	return find_next_zero_bit(cpumask_bits(srcp), small_cpumask_bits, n+1);
255 }
256 
257 #if NR_CPUS == 1
258 /* Uniprocessor: there is only one valid CPU */
259 static __always_inline
cpumask_local_spread(unsigned int i,int node)260 unsigned int cpumask_local_spread(unsigned int i, int node)
261 {
262 	return 0;
263 }
264 
265 static __always_inline
cpumask_any_and_distribute(const struct cpumask * src1p,const struct cpumask * src2p)266 unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
267 					const struct cpumask *src2p)
268 {
269 	return cpumask_first_and(src1p, src2p);
270 }
271 
272 static __always_inline
cpumask_any_distribute(const struct cpumask * srcp)273 unsigned int cpumask_any_distribute(const struct cpumask *srcp)
274 {
275 	return cpumask_first(srcp);
276 }
277 #else
278 unsigned int cpumask_local_spread(unsigned int i, int node);
279 unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
280 			       const struct cpumask *src2p);
281 unsigned int cpumask_any_distribute(const struct cpumask *srcp);
282 #endif /* NR_CPUS */
283 
284 /**
285  * cpumask_next_and - get the next cpu in *src1p & *src2p
286  * @n: the cpu prior to the place to search (i.e. return will be > @n)
287  * @src1p: the first cpumask pointer
288  * @src2p: the second cpumask pointer
289  *
290  * Return: >= nr_cpu_ids if no further cpus set in both.
291  */
292 static __always_inline
cpumask_next_and(int n,const struct cpumask * src1p,const struct cpumask * src2p)293 unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
294 			      const struct cpumask *src2p)
295 {
296 	/* -1 is a legal arg here. */
297 	if (n != -1)
298 		cpumask_check(n);
299 	return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p),
300 		small_cpumask_bits, n + 1);
301 }
302 
303 /**
304  * cpumask_next_andnot - get the next cpu in *src1p & ~*src2p
305  * @n: the cpu prior to the place to search (i.e. return will be > @n)
306  * @src1p: the first cpumask pointer
307  * @src2p: the second cpumask pointer
308  *
309  * Return: >= nr_cpu_ids if no further cpus set in both.
310  */
311 static __always_inline
cpumask_next_andnot(int n,const struct cpumask * src1p,const struct cpumask * src2p)312 unsigned int cpumask_next_andnot(int n, const struct cpumask *src1p,
313 				 const struct cpumask *src2p)
314 {
315 	/* -1 is a legal arg here. */
316 	if (n != -1)
317 		cpumask_check(n);
318 	return find_next_andnot_bit(cpumask_bits(src1p), cpumask_bits(src2p),
319 		small_cpumask_bits, n + 1);
320 }
321 
322 /**
323  * cpumask_next_and_wrap - get the next cpu in *src1p & *src2p, starting from
324  *			   @n+1. If nothing found, wrap around and start from
325  *			   the beginning
326  * @n: the cpu prior to the place to search (i.e. search starts from @n+1)
327  * @src1p: the first cpumask pointer
328  * @src2p: the second cpumask pointer
329  *
330  * Return: next set bit, wrapped if needed, or >= nr_cpu_ids if @src1p & @src2p is empty.
331  */
332 static __always_inline
cpumask_next_and_wrap(int n,const struct cpumask * src1p,const struct cpumask * src2p)333 unsigned int cpumask_next_and_wrap(int n, const struct cpumask *src1p,
334 			      const struct cpumask *src2p)
335 {
336 	/* -1 is a legal arg here. */
337 	if (n != -1)
338 		cpumask_check(n);
339 	return find_next_and_bit_wrap(cpumask_bits(src1p), cpumask_bits(src2p),
340 		small_cpumask_bits, n + 1);
341 }
342 
343 /**
344  * cpumask_next_wrap - get the next cpu in *src, starting from @n+1. If nothing
345  *		       found, wrap around and start from the beginning
346  * @n: the cpu prior to the place to search (i.e. search starts from @n+1)
347  * @src: cpumask pointer
348  *
349  * Return: next set bit, wrapped if needed, or >= nr_cpu_ids if @src is empty.
350  */
351 static __always_inline
cpumask_next_wrap(int n,const struct cpumask * src)352 unsigned int cpumask_next_wrap(int n, const struct cpumask *src)
353 {
354 	/* -1 is a legal arg here. */
355 	if (n != -1)
356 		cpumask_check(n);
357 	return find_next_bit_wrap(cpumask_bits(src), small_cpumask_bits, n + 1);
358 }
359 
360 /**
361  * cpumask_random - get random cpu in *src.
362  * @src: cpumask pointer
363  *
364  * Return: random set bit, or >= nr_cpu_ids if @src is empty.
365  */
366 static __always_inline
cpumask_random(const struct cpumask * src)367 unsigned int cpumask_random(const struct cpumask *src)
368 {
369 	return find_random_bit(cpumask_bits(src), nr_cpu_ids);
370 }
371 
372 /**
373  * for_each_cpu - iterate over every cpu in a mask
374  * @cpu: the (optionally unsigned) integer iterator
375  * @mask: the cpumask pointer
376  *
377  * After the loop, cpu is >= nr_cpu_ids.
378  */
379 #define for_each_cpu(cpu, mask)				\
380 	for_each_set_bit(cpu, cpumask_bits(mask), small_cpumask_bits)
381 
382 /**
383  * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location
384  * @cpu: the (optionally unsigned) integer iterator
385  * @mask: the cpumask pointer
386  * @start: the start location
387  *
388  * The implementation does not assume any bit in @mask is set (including @start).
389  *
390  * After the loop, cpu is >= nr_cpu_ids.
391  */
392 #define for_each_cpu_wrap(cpu, mask, start)				\
393 	for_each_set_bit_wrap(cpu, cpumask_bits(mask), small_cpumask_bits, start)
394 
395 /**
396  * for_each_cpu_and - iterate over every cpu in both masks
397  * @cpu: the (optionally unsigned) integer iterator
398  * @mask1: the first cpumask pointer
399  * @mask2: the second cpumask pointer
400  *
401  * This saves a temporary CPU mask in many places.  It is equivalent to:
402  *	struct cpumask tmp;
403  *	cpumask_and(&tmp, &mask1, &mask2);
404  *	for_each_cpu(cpu, &tmp)
405  *		...
406  *
407  * After the loop, cpu is >= nr_cpu_ids.
408  */
409 #define for_each_cpu_and(cpu, mask1, mask2)				\
410 	for_each_and_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
411 
412 /**
413  * for_each_cpu_andnot - iterate over every cpu present in one mask, excluding
414  *			 those present in another.
415  * @cpu: the (optionally unsigned) integer iterator
416  * @mask1: the first cpumask pointer
417  * @mask2: the second cpumask pointer
418  *
419  * This saves a temporary CPU mask in many places.  It is equivalent to:
420  *	struct cpumask tmp;
421  *	cpumask_andnot(&tmp, &mask1, &mask2);
422  *	for_each_cpu(cpu, &tmp)
423  *		...
424  *
425  * After the loop, cpu is >= nr_cpu_ids.
426  */
427 #define for_each_cpu_andnot(cpu, mask1, mask2)				\
428 	for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
429 
430 /**
431  * for_each_cpu_or - iterate over every cpu present in either mask
432  * @cpu: the (optionally unsigned) integer iterator
433  * @mask1: the first cpumask pointer
434  * @mask2: the second cpumask pointer
435  *
436  * This saves a temporary CPU mask in many places.  It is equivalent to:
437  *	struct cpumask tmp;
438  *	cpumask_or(&tmp, &mask1, &mask2);
439  *	for_each_cpu(cpu, &tmp)
440  *		...
441  *
442  * After the loop, cpu is >= nr_cpu_ids.
443  */
444 #define for_each_cpu_or(cpu, mask1, mask2)				\
445 	for_each_or_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), small_cpumask_bits)
446 
447 /**
448  * for_each_cpu_from - iterate over CPUs present in @mask, from @cpu to the end of @mask.
449  * @cpu: the (optionally unsigned) integer iterator
450  * @mask: the cpumask pointer
451  *
452  * After the loop, cpu is >= nr_cpu_ids.
453  */
454 #define for_each_cpu_from(cpu, mask)				\
455 	for_each_set_bit_from(cpu, cpumask_bits(mask), small_cpumask_bits)
456 
457 /**
458  * cpumask_any_but - return an arbitrary cpu in a cpumask, but not this one.
459  * @mask: the cpumask to search
460  * @cpu: the cpu to ignore.
461  *
462  * Often used to find any cpu but smp_processor_id() in a mask.
463  * If @cpu == -1, the function is equivalent to cpumask_any().
464  * Return: >= nr_cpu_ids if no cpus set.
465  */
466 static __always_inline
cpumask_any_but(const struct cpumask * mask,int cpu)467 unsigned int cpumask_any_but(const struct cpumask *mask, int cpu)
468 {
469 	unsigned int i;
470 
471 	/* -1 is a legal arg here. */
472 	if (cpu != -1)
473 		cpumask_check(cpu);
474 
475 	for_each_cpu(i, mask)
476 		if (i != cpu)
477 			break;
478 	return i;
479 }
480 
481 /**
482  * cpumask_any_and_but - pick an arbitrary cpu from *mask1 & *mask2, but not this one.
483  * @mask1: the first input cpumask
484  * @mask2: the second input cpumask
485  * @cpu: the cpu to ignore
486  *
487  * If @cpu == -1, the function is equivalent to cpumask_any_and().
488  * Returns >= nr_cpu_ids if no cpus set.
489  */
490 static __always_inline
cpumask_any_and_but(const struct cpumask * mask1,const struct cpumask * mask2,int cpu)491 unsigned int cpumask_any_and_but(const struct cpumask *mask1,
492 				 const struct cpumask *mask2,
493 				 int cpu)
494 {
495 	unsigned int i;
496 
497 	/* -1 is a legal arg here. */
498 	if (cpu != -1)
499 		cpumask_check(cpu);
500 
501 	i = cpumask_first_and(mask1, mask2);
502 	if (i != cpu)
503 		return i;
504 
505 	return cpumask_next_and(cpu, mask1, mask2);
506 }
507 
508 /**
509  * cpumask_any_andnot_but - pick an arbitrary cpu from *mask1 & ~*mask2, but not this one.
510  * @mask1: the first input cpumask
511  * @mask2: the second input cpumask
512  * @cpu: the cpu to ignore
513  *
514  * If @cpu == -1, the function returns the first matching cpu.
515  * Returns >= nr_cpu_ids if no cpus set.
516  */
517 static __always_inline
cpumask_any_andnot_but(const struct cpumask * mask1,const struct cpumask * mask2,int cpu)518 unsigned int cpumask_any_andnot_but(const struct cpumask *mask1,
519 				    const struct cpumask *mask2,
520 				    int cpu)
521 {
522 	unsigned int i;
523 
524 	/* -1 is a legal arg here. */
525 	if (cpu != -1)
526 		cpumask_check(cpu);
527 
528 	i = cpumask_first_andnot(mask1, mask2);
529 	if (i != cpu)
530 		return i;
531 
532 	return cpumask_next_andnot(cpu, mask1, mask2);
533 }
534 
535 /**
536  * cpumask_nth - get the Nth cpu in a cpumask
537  * @srcp: the cpumask pointer
538  * @cpu: the Nth cpu to find, starting from 0
539  *
540  * Return: >= nr_cpu_ids if such cpu doesn't exist.
541  */
542 static __always_inline
cpumask_nth(unsigned int cpu,const struct cpumask * srcp)543 unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp)
544 {
545 	return find_nth_bit(cpumask_bits(srcp), small_cpumask_bits, cpumask_check(cpu));
546 }
547 
548 /**
549  * cpumask_nth_and - get the Nth cpu in 2 cpumasks
550  * @srcp1: the cpumask pointer
551  * @srcp2: the cpumask pointer
552  * @cpu: the Nth cpu to find, starting from 0
553  *
554  * Return: >= nr_cpu_ids if such cpu doesn't exist.
555  */
556 static __always_inline
cpumask_nth_and(unsigned int cpu,const struct cpumask * srcp1,const struct cpumask * srcp2)557 unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1,
558 							const struct cpumask *srcp2)
559 {
560 	return find_nth_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2),
561 				small_cpumask_bits, cpumask_check(cpu));
562 }
563 
564 /**
565  * cpumask_nth_and_andnot - get the Nth cpu set in 1st and 2nd cpumask, and clear in 3rd.
566  * @srcp1: the cpumask pointer
567  * @srcp2: the cpumask pointer
568  * @srcp3: the cpumask pointer
569  * @cpu: the Nth cpu to find, starting from 0
570  *
571  * Return: >= nr_cpu_ids if such cpu doesn't exist.
572  */
573 static __always_inline
cpumask_nth_and_andnot(unsigned int cpu,const struct cpumask * srcp1,const struct cpumask * srcp2,const struct cpumask * srcp3)574 unsigned int cpumask_nth_and_andnot(unsigned int cpu, const struct cpumask *srcp1,
575 							const struct cpumask *srcp2,
576 							const struct cpumask *srcp3)
577 {
578 	return find_nth_and_andnot_bit(cpumask_bits(srcp1),
579 					cpumask_bits(srcp2),
580 					cpumask_bits(srcp3),
581 					small_cpumask_bits, cpumask_check(cpu));
582 }
583 
584 #define CPU_BITS_NONE						\
585 {								\
586 	[0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL			\
587 }
588 
589 #define CPU_BITS_CPU0						\
590 {								\
591 	[0] =  1UL						\
592 }
593 
594 /**
595  * cpumask_set_cpu - set a cpu in a cpumask
596  * @cpu: cpu number (< nr_cpu_ids)
597  * @dstp: the cpumask pointer
598  */
599 static __always_inline
cpumask_set_cpu(unsigned int cpu,struct cpumask * dstp)600 void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
601 {
602 	set_bit(cpumask_check(cpu), cpumask_bits(dstp));
603 }
604 
605 static __always_inline
__cpumask_set_cpu(unsigned int cpu,struct cpumask * dstp)606 void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
607 {
608 	__set_bit(cpumask_check(cpu), cpumask_bits(dstp));
609 }
610 
611 /**
612  * cpumask_clear_cpus - clear cpus in a cpumask
613  * @dstp:  the cpumask pointer
614  * @cpu:   cpu number (< nr_cpu_ids)
615  * @ncpus: number of cpus to clear (< nr_cpu_ids)
616  */
cpumask_clear_cpus(struct cpumask * dstp,unsigned int cpu,unsigned int ncpus)617 static __always_inline void cpumask_clear_cpus(struct cpumask *dstp,
618 						unsigned int cpu, unsigned int ncpus)
619 {
620 	cpumask_check(cpu + ncpus - 1);
621 	bitmap_clear(cpumask_bits(dstp), cpumask_check(cpu), ncpus);
622 }
623 
624 /**
625  * cpumask_clear_cpu - clear a cpu in a cpumask
626  * @cpu: cpu number (< nr_cpu_ids)
627  * @dstp: the cpumask pointer
628  */
cpumask_clear_cpu(int cpu,struct cpumask * dstp)629 static __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
630 {
631 	clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
632 }
633 
__cpumask_clear_cpu(int cpu,struct cpumask * dstp)634 static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp)
635 {
636 	__clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
637 }
638 
639 /**
640  * cpumask_test_cpu - test for a cpu in a cpumask
641  * @cpu: cpu number (< nr_cpu_ids)
642  * @cpumask: the cpumask pointer
643  *
644  * Return: true if @cpu is set in @cpumask, else returns false
645  */
646 static __always_inline
cpumask_test_cpu(int cpu,const struct cpumask * cpumask)647 bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
648 {
649 	return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
650 }
651 
652 /**
653  * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
654  * @cpu: cpu number (< nr_cpu_ids)
655  * @cpumask: the cpumask pointer
656  *
657  * test_and_set_bit wrapper for cpumasks.
658  *
659  * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
660  */
661 static __always_inline
cpumask_test_and_set_cpu(int cpu,struct cpumask * cpumask)662 bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
663 {
664 	return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
665 }
666 
667 /**
668  * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
669  * @cpu: cpu number (< nr_cpu_ids)
670  * @cpumask: the cpumask pointer
671  *
672  * test_and_clear_bit wrapper for cpumasks.
673  *
674  * Return: true if @cpu is set in old bitmap of @cpumask, else returns false
675  */
676 static __always_inline
cpumask_test_and_clear_cpu(int cpu,struct cpumask * cpumask)677 bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
678 {
679 	return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
680 }
681 
682 /**
683  * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
684  * @dstp: the cpumask pointer
685  */
cpumask_setall(struct cpumask * dstp)686 static __always_inline void cpumask_setall(struct cpumask *dstp)
687 {
688 	if (small_const_nbits(small_cpumask_bits)) {
689 		cpumask_bits(dstp)[0] = BITMAP_LAST_WORD_MASK(nr_cpumask_bits);
690 		return;
691 	}
692 	bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
693 }
694 
695 /**
696  * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
697  * @dstp: the cpumask pointer
698  */
cpumask_clear(struct cpumask * dstp)699 static __always_inline void cpumask_clear(struct cpumask *dstp)
700 {
701 	bitmap_zero(cpumask_bits(dstp), large_cpumask_bits);
702 }
703 
704 /**
705  * cpumask_and - *dstp = *src1p & *src2p
706  * @dstp: the cpumask result
707  * @src1p: the first input
708  * @src2p: the second input
709  *
710  * Return: false if *@dstp is empty, else returns true
711  */
712 static __always_inline
cpumask_and(struct cpumask * dstp,const struct cpumask * src1p,const struct cpumask * src2p)713 bool cpumask_and(struct cpumask *dstp, const struct cpumask *src1p,
714 		 const struct cpumask *src2p)
715 {
716 	return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
717 				       cpumask_bits(src2p), small_cpumask_bits);
718 }
719 
720 /**
721  * cpumask_or - *dstp = *src1p | *src2p
722  * @dstp: the cpumask result
723  * @src1p: the first input
724  * @src2p: the second input
725  */
726 static __always_inline
cpumask_or(struct cpumask * dstp,const struct cpumask * src1p,const struct cpumask * src2p)727 void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
728 		const struct cpumask *src2p)
729 {
730 	bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
731 				      cpumask_bits(src2p), small_cpumask_bits);
732 }
733 
734 /**
735  * cpumask_weighted_or - *dstp = *src1p | *src2p and return the weight of the result
736  * @dstp: the cpumask result
737  * @src1p: the first input
738  * @src2p: the second input
739  *
740  * Return: The number of bits set in the resulting cpumask @dstp
741  */
742 static __always_inline
cpumask_weighted_or(struct cpumask * dstp,const struct cpumask * src1p,const struct cpumask * src2p)743 unsigned int cpumask_weighted_or(struct cpumask *dstp, const struct cpumask *src1p,
744 				 const struct cpumask *src2p)
745 {
746 	return bitmap_weighted_or(cpumask_bits(dstp), cpumask_bits(src1p),
747 				  cpumask_bits(src2p), small_cpumask_bits);
748 }
749 
750 /**
751  * cpumask_xor - *dstp = *src1p ^ *src2p
752  * @dstp: the cpumask result
753  * @src1p: the first input
754  * @src2p: the second input
755  */
756 static __always_inline
cpumask_xor(struct cpumask * dstp,const struct cpumask * src1p,const struct cpumask * src2p)757 void cpumask_xor(struct cpumask *dstp, const struct cpumask *src1p,
758 		 const struct cpumask *src2p)
759 {
760 	bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
761 				       cpumask_bits(src2p), small_cpumask_bits);
762 }
763 
764 /**
765  * cpumask_andnot - *dstp = *src1p & ~*src2p
766  * @dstp: the cpumask result
767  * @src1p: the first input
768  * @src2p: the second input
769  *
770  * Return: false if *@dstp is empty, else returns true
771  */
772 static __always_inline
cpumask_andnot(struct cpumask * dstp,const struct cpumask * src1p,const struct cpumask * src2p)773 bool cpumask_andnot(struct cpumask *dstp, const struct cpumask *src1p,
774 		    const struct cpumask *src2p)
775 {
776 	return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
777 					  cpumask_bits(src2p), small_cpumask_bits);
778 }
779 
780 /**
781  * cpumask_equal - *src1p == *src2p
782  * @src1p: the first input
783  * @src2p: the second input
784  *
785  * Return: true if the cpumasks are equal, false if not
786  */
787 static __always_inline
cpumask_equal(const struct cpumask * src1p,const struct cpumask * src2p)788 bool cpumask_equal(const struct cpumask *src1p, const struct cpumask *src2p)
789 {
790 	return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
791 						 small_cpumask_bits);
792 }
793 
794 /**
795  * cpumask_or_equal - *src1p | *src2p == *src3p
796  * @src1p: the first input
797  * @src2p: the second input
798  * @src3p: the third input
799  *
800  * Return: true if first cpumask ORed with second cpumask == third cpumask,
801  *	   otherwise false
802  */
803 static __always_inline
cpumask_or_equal(const struct cpumask * src1p,const struct cpumask * src2p,const struct cpumask * src3p)804 bool cpumask_or_equal(const struct cpumask *src1p, const struct cpumask *src2p,
805 		      const struct cpumask *src3p)
806 {
807 	return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p),
808 			       cpumask_bits(src3p), small_cpumask_bits);
809 }
810 
811 /**
812  * cpumask_intersects - (*src1p & *src2p) != 0
813  * @src1p: the first input
814  * @src2p: the second input
815  *
816  * Return: true if first cpumask ANDed with second cpumask is non-empty,
817  *	   otherwise false
818  */
819 static __always_inline
cpumask_intersects(const struct cpumask * src1p,const struct cpumask * src2p)820 bool cpumask_intersects(const struct cpumask *src1p, const struct cpumask *src2p)
821 {
822 	return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
823 						      small_cpumask_bits);
824 }
825 
826 /**
827  * cpumask_subset - (*src1p & ~*src2p) == 0
828  * @src1p: the first input
829  * @src2p: the second input
830  *
831  * Return: true if *@src1p is a subset of *@src2p, else returns false
832  */
833 static __always_inline
cpumask_subset(const struct cpumask * src1p,const struct cpumask * src2p)834 bool cpumask_subset(const struct cpumask *src1p, const struct cpumask *src2p)
835 {
836 	return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
837 						  small_cpumask_bits);
838 }
839 
840 /**
841  * cpumask_empty - *srcp == 0
842  * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
843  *
844  * Return: true if srcp is empty (has no bits set), else false
845  */
cpumask_empty(const struct cpumask * srcp)846 static __always_inline bool cpumask_empty(const struct cpumask *srcp)
847 {
848 	return bitmap_empty(cpumask_bits(srcp), small_cpumask_bits);
849 }
850 
851 /**
852  * cpumask_full - *srcp == 0xFFFFFFFF...
853  * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
854  *
855  * Return: true if srcp is full (has all bits set), else false
856  */
cpumask_full(const struct cpumask * srcp)857 static __always_inline bool cpumask_full(const struct cpumask *srcp)
858 {
859 	return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
860 }
861 
862 /**
863  * cpumask_weight - Count of bits in *srcp
864  * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
865  *
866  * Return: count of bits set in *srcp
867  */
cpumask_weight(const struct cpumask * srcp)868 static __always_inline unsigned int cpumask_weight(const struct cpumask *srcp)
869 {
870 	return bitmap_weight(cpumask_bits(srcp), small_cpumask_bits);
871 }
872 
873 /**
874  * cpumask_weight_and - Count of bits in (*srcp1 & *srcp2)
875  * @srcp1: the cpumask to count bits (< nr_cpu_ids) in.
876  * @srcp2: the cpumask to count bits (< nr_cpu_ids) in.
877  *
878  * Return: count of bits set in both *srcp1 and *srcp2
879  */
880 static __always_inline
cpumask_weight_and(const struct cpumask * srcp1,const struct cpumask * srcp2)881 unsigned int cpumask_weight_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
882 {
883 	return bitmap_weight_and(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
884 }
885 
886 /**
887  * cpumask_weight_andnot - Count of bits in (*srcp1 & ~*srcp2)
888  * @srcp1: the cpumask to count bits (< nr_cpu_ids) in.
889  * @srcp2: the cpumask to count bits (< nr_cpu_ids) in.
890  *
891  * Return: count of bits set in both *srcp1 and *srcp2
892  */
893 static __always_inline
cpumask_weight_andnot(const struct cpumask * srcp1,const struct cpumask * srcp2)894 unsigned int cpumask_weight_andnot(const struct cpumask *srcp1,
895 				   const struct cpumask *srcp2)
896 {
897 	return bitmap_weight_andnot(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);
898 }
899 
900 /**
901  * cpumask_shift_right - *dstp = *srcp >> n
902  * @dstp: the cpumask result
903  * @srcp: the input to shift
904  * @n: the number of bits to shift by
905  */
906 static __always_inline
cpumask_shift_right(struct cpumask * dstp,const struct cpumask * srcp,int n)907 void cpumask_shift_right(struct cpumask *dstp, const struct cpumask *srcp, int n)
908 {
909 	bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
910 					       small_cpumask_bits);
911 }
912 
913 /**
914  * cpumask_shift_left - *dstp = *srcp << n
915  * @dstp: the cpumask result
916  * @srcp: the input to shift
917  * @n: the number of bits to shift by
918  */
919 static __always_inline
cpumask_shift_left(struct cpumask * dstp,const struct cpumask * srcp,int n)920 void cpumask_shift_left(struct cpumask *dstp, const struct cpumask *srcp, int n)
921 {
922 	bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
923 					      nr_cpumask_bits);
924 }
925 
926 /**
927  * cpumask_copy - *dstp = *srcp
928  * @dstp: the result
929  * @srcp: the input cpumask
930  */
931 static __always_inline
cpumask_copy(struct cpumask * dstp,const struct cpumask * srcp)932 void cpumask_copy(struct cpumask *dstp, const struct cpumask *srcp)
933 {
934 	bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), large_cpumask_bits);
935 }
936 
937 /**
938  * cpumask_any - pick an arbitrary cpu from *srcp
939  * @srcp: the input cpumask
940  *
941  * Return: >= nr_cpu_ids if no cpus set.
942  */
943 #define cpumask_any(srcp) cpumask_first(srcp)
944 
945 /**
946  * cpumask_any_and - pick an arbitrary cpu from *mask1 & *mask2
947  * @mask1: the first input cpumask
948  * @mask2: the second input cpumask
949  *
950  * Return: >= nr_cpu_ids if no cpus set.
951  */
952 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
953 
954 /**
955  * cpumask_of - the cpumask containing just a given cpu
956  * @cpu: the cpu (<= nr_cpu_ids)
957  */
958 #define cpumask_of(cpu) (get_cpu_mask(cpu))
959 
960 /**
961  * cpumask_parse_user - extract a cpumask from a user string
962  * @buf: the buffer to extract from
963  * @len: the length of the buffer
964  * @dstp: the cpumask to set.
965  *
966  * Return: -errno, or 0 for success.
967  */
968 static __always_inline
cpumask_parse_user(const char __user * buf,int len,struct cpumask * dstp)969 int cpumask_parse_user(const char __user *buf, int len, struct cpumask *dstp)
970 {
971 	return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
972 }
973 
974 /**
975  * cpumask_parselist_user - extract a cpumask from a user string
976  * @buf: the buffer to extract from
977  * @len: the length of the buffer
978  * @dstp: the cpumask to set.
979  *
980  * Return: -errno, or 0 for success.
981  */
982 static __always_inline
cpumask_parselist_user(const char __user * buf,int len,struct cpumask * dstp)983 int cpumask_parselist_user(const char __user *buf, int len, struct cpumask *dstp)
984 {
985 	return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
986 				     nr_cpumask_bits);
987 }
988 
989 /**
990  * cpumask_parse - extract a cpumask from a string
991  * @buf: the buffer to extract from
992  * @dstp: the cpumask to set.
993  *
994  * Return: -errno, or 0 for success.
995  */
cpumask_parse(const char * buf,struct cpumask * dstp)996 static __always_inline int cpumask_parse(const char *buf, struct cpumask *dstp)
997 {
998 	return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits);
999 }
1000 
1001 /**
1002  * cpulist_parse - extract a cpumask from a user string of ranges
1003  * @buf: the buffer to extract from
1004  * @dstp: the cpumask to set.
1005  *
1006  * Return: -errno, or 0 for success.
1007  */
cpulist_parse(const char * buf,struct cpumask * dstp)1008 static __always_inline int cpulist_parse(const char *buf, struct cpumask *dstp)
1009 {
1010 	return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits);
1011 }
1012 
1013 /**
1014  * cpumask_size - calculate size to allocate for a 'struct cpumask' in bytes
1015  *
1016  * Return: size to allocate for a &struct cpumask in bytes
1017  */
cpumask_size(void)1018 static __always_inline unsigned int cpumask_size(void)
1019 {
1020 	return bitmap_size(large_cpumask_bits);
1021 }
1022 
1023 #ifdef CONFIG_CPUMASK_OFFSTACK
1024 
1025 #define this_cpu_cpumask_var_ptr(x)	this_cpu_read(x)
1026 #define __cpumask_var_read_mostly	__read_mostly
1027 #define CPUMASK_VAR_NULL		NULL
1028 
1029 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
1030 
1031 static __always_inline
zalloc_cpumask_var_node(cpumask_var_t * mask,gfp_t flags,int node)1032 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
1033 {
1034 	return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node);
1035 }
1036 
1037 /**
1038  * alloc_cpumask_var - allocate a struct cpumask
1039  * @mask: pointer to cpumask_var_t where the cpumask is returned
1040  * @flags: GFP_ flags
1041  *
1042  * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
1043  * a nop returning a constant 1 (in <linux/cpumask.h>).
1044  *
1045  * See alloc_cpumask_var_node.
1046  *
1047  * Return: %true if allocation succeeded, %false if not
1048  */
1049 static __always_inline
alloc_cpumask_var(cpumask_var_t * mask,gfp_t flags)1050 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
1051 {
1052 	return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE);
1053 }
1054 
1055 static __always_inline
zalloc_cpumask_var(cpumask_var_t * mask,gfp_t flags)1056 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
1057 {
1058 	return alloc_cpumask_var(mask, flags | __GFP_ZERO);
1059 }
1060 
1061 void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
1062 void free_cpumask_var(cpumask_var_t mask);
1063 void free_bootmem_cpumask_var(cpumask_var_t mask);
1064 
cpumask_available(cpumask_var_t mask)1065 static __always_inline bool cpumask_available(cpumask_var_t mask)
1066 {
1067 	return mask != NULL;
1068 }
1069 
1070 #else
1071 
1072 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
1073 #define __cpumask_var_read_mostly
1074 #define CPUMASK_VAR_NULL {}
1075 
alloc_cpumask_var(cpumask_var_t * mask,gfp_t flags)1076 static __always_inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
1077 {
1078 	return true;
1079 }
1080 
alloc_cpumask_var_node(cpumask_var_t * mask,gfp_t flags,int node)1081 static __always_inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
1082 					  int node)
1083 {
1084 	return true;
1085 }
1086 
zalloc_cpumask_var(cpumask_var_t * mask,gfp_t flags)1087 static __always_inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
1088 {
1089 	cpumask_clear(*mask);
1090 	return true;
1091 }
1092 
zalloc_cpumask_var_node(cpumask_var_t * mask,gfp_t flags,int node)1093 static __always_inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
1094 					  int node)
1095 {
1096 	cpumask_clear(*mask);
1097 	return true;
1098 }
1099 
alloc_bootmem_cpumask_var(cpumask_var_t * mask)1100 static __always_inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
1101 {
1102 }
1103 
free_cpumask_var(cpumask_var_t mask)1104 static __always_inline void free_cpumask_var(cpumask_var_t mask)
1105 {
1106 }
1107 
free_bootmem_cpumask_var(cpumask_var_t mask)1108 static __always_inline void free_bootmem_cpumask_var(cpumask_var_t mask)
1109 {
1110 }
1111 
cpumask_available(cpumask_var_t mask)1112 static __always_inline bool cpumask_available(cpumask_var_t mask)
1113 {
1114 	return true;
1115 }
1116 #endif /* CONFIG_CPUMASK_OFFSTACK */
1117 
1118 DEFINE_FREE(free_cpumask_var, struct cpumask *, if (_T) free_cpumask_var(_T));
1119 
1120 /* It's common to want to use cpu_all_mask in struct member initializers,
1121  * so it has to refer to an address rather than a pointer. */
1122 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
1123 #define cpu_all_mask to_cpumask(cpu_all_bits)
1124 
1125 /* First bits of cpu_bit_bitmap are in fact unset. */
1126 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
1127 
1128 #if NR_CPUS == 1
1129 /* Uniprocessor: the possible/online/present masks are always "1" */
1130 #define for_each_possible_cpu(cpu)	for ((cpu) = 0; (cpu) < 1; (cpu)++)
1131 #define for_each_online_cpu(cpu)	for ((cpu) = 0; (cpu) < 1; (cpu)++)
1132 #define for_each_present_cpu(cpu)	for ((cpu) = 0; (cpu) < 1; (cpu)++)
1133 
1134 #define for_each_possible_cpu_wrap(cpu, start)	\
1135 	for ((void)(start), (cpu) = 0; (cpu) < 1; (cpu)++)
1136 #define for_each_online_cpu_wrap(cpu, start)	\
1137 	for ((void)(start), (cpu) = 0; (cpu) < 1; (cpu)++)
1138 #else
1139 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
1140 #define for_each_online_cpu(cpu)   for_each_cpu((cpu), cpu_online_mask)
1141 #define for_each_enabled_cpu(cpu)   for_each_cpu((cpu), cpu_enabled_mask)
1142 #define for_each_present_cpu(cpu)  for_each_cpu((cpu), cpu_present_mask)
1143 
1144 #define for_each_possible_cpu_wrap(cpu, start)	\
1145 	for_each_cpu_wrap((cpu), cpu_possible_mask, (start))
1146 #define for_each_online_cpu_wrap(cpu, start)	\
1147 	for_each_cpu_wrap((cpu), cpu_online_mask, (start))
1148 #endif
1149 
1150 /* Wrappers for arch boot code to manipulate normally-constant masks */
1151 void init_cpu_present(const struct cpumask *src);
1152 void init_cpu_possible(const struct cpumask *src);
1153 
1154 #define assign_cpu(cpu, mask, val)	\
1155 	assign_bit(cpumask_check(cpu), cpumask_bits(mask), (val))
1156 
1157 #define __assign_cpu(cpu, mask, val)	\
1158 	__assign_bit(cpumask_check(cpu), cpumask_bits(mask), (val))
1159 
1160 #define set_cpu_enabled(cpu, enabled)	assign_cpu((cpu), &__cpu_enabled_mask, (enabled))
1161 #define set_cpu_present(cpu, present)	assign_cpu((cpu), &__cpu_present_mask, (present))
1162 #define set_cpu_active(cpu, active)	assign_cpu((cpu), &__cpu_active_mask, (active))
1163 #define set_cpu_dying(cpu, dying)	assign_cpu((cpu), &__cpu_dying_mask, (dying))
1164 
1165 void set_cpu_online(unsigned int cpu, bool online);
1166 void set_cpu_possible(unsigned int cpu, bool possible);
1167 
1168 /**
1169  * to_cpumask - convert a NR_CPUS bitmap to a struct cpumask *
1170  * @bitmap: the bitmap
1171  *
1172  * There are a few places where cpumask_var_t isn't appropriate and
1173  * static cpumasks must be used (eg. very early boot), yet we don't
1174  * expose the definition of 'struct cpumask'.
1175  *
1176  * This does the conversion, and can be used as a constant initializer.
1177  */
1178 #define to_cpumask(bitmap)						\
1179 	((struct cpumask *)(1 ? (bitmap)				\
1180 			    : (void *)sizeof(__check_is_bitmap(bitmap))))
1181 
__check_is_bitmap(const unsigned long * bitmap)1182 static __always_inline int __check_is_bitmap(const unsigned long *bitmap)
1183 {
1184 	return 1;
1185 }
1186 
1187 /*
1188  * Special-case data structure for "single bit set only" constant CPU masks.
1189  *
1190  * We pre-generate all the 64 (or 32) possible bit positions, with enough
1191  * padding to the left and the right, and return the constant pointer
1192  * appropriately offset.
1193  */
1194 extern const unsigned long
1195 	cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
1196 
get_cpu_mask(unsigned int cpu)1197 static __always_inline const struct cpumask *get_cpu_mask(unsigned int cpu)
1198 {
1199 	const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
1200 	p -= cpu / BITS_PER_LONG;
1201 	return to_cpumask(p);
1202 }
1203 
1204 #if NR_CPUS > 1
1205 /**
1206  * num_online_cpus() - Read the number of online CPUs
1207  *
1208  * Despite the fact that __num_online_cpus is of type atomic_t, this
1209  * interface gives only a momentary snapshot and is not protected against
1210  * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held
1211  * region.
1212  *
1213  * Return: momentary snapshot of the number of online CPUs
1214  */
num_online_cpus(void)1215 static __always_inline unsigned int num_online_cpus(void)
1216 {
1217 	return raw_atomic_read(&__num_online_cpus);
1218 }
1219 
num_possible_cpus(void)1220 static __always_inline unsigned int num_possible_cpus(void)
1221 {
1222 	return __num_possible_cpus;
1223 }
1224 
1225 #define num_enabled_cpus()	cpumask_weight(cpu_enabled_mask)
1226 #define num_present_cpus()	cpumask_weight(cpu_present_mask)
1227 #define num_active_cpus()	cpumask_weight(cpu_active_mask)
1228 
cpu_online(unsigned int cpu)1229 static __always_inline bool cpu_online(unsigned int cpu)
1230 {
1231 	return cpumask_test_cpu(cpu, cpu_online_mask);
1232 }
1233 
cpu_enabled(unsigned int cpu)1234 static __always_inline bool cpu_enabled(unsigned int cpu)
1235 {
1236 	return cpumask_test_cpu(cpu, cpu_enabled_mask);
1237 }
1238 
cpu_possible(unsigned int cpu)1239 static __always_inline bool cpu_possible(unsigned int cpu)
1240 {
1241 	return cpumask_test_cpu(cpu, cpu_possible_mask);
1242 }
1243 
cpu_present(unsigned int cpu)1244 static __always_inline bool cpu_present(unsigned int cpu)
1245 {
1246 	return cpumask_test_cpu(cpu, cpu_present_mask);
1247 }
1248 
cpu_active(unsigned int cpu)1249 static __always_inline bool cpu_active(unsigned int cpu)
1250 {
1251 	return cpumask_test_cpu(cpu, cpu_active_mask);
1252 }
1253 
cpu_dying(unsigned int cpu)1254 static __always_inline bool cpu_dying(unsigned int cpu)
1255 {
1256 	return cpumask_test_cpu(cpu, cpu_dying_mask);
1257 }
1258 
1259 #else
1260 
1261 #define num_online_cpus()	1U
1262 #define num_possible_cpus()	1U
1263 #define num_enabled_cpus()	1U
1264 #define num_present_cpus()	1U
1265 #define num_active_cpus()	1U
1266 
cpu_online(unsigned int cpu)1267 static __always_inline bool cpu_online(unsigned int cpu)
1268 {
1269 	return cpu == 0;
1270 }
1271 
cpu_possible(unsigned int cpu)1272 static __always_inline bool cpu_possible(unsigned int cpu)
1273 {
1274 	return cpu == 0;
1275 }
1276 
cpu_enabled(unsigned int cpu)1277 static __always_inline bool cpu_enabled(unsigned int cpu)
1278 {
1279 	return cpu == 0;
1280 }
1281 
cpu_present(unsigned int cpu)1282 static __always_inline bool cpu_present(unsigned int cpu)
1283 {
1284 	return cpu == 0;
1285 }
1286 
cpu_active(unsigned int cpu)1287 static __always_inline bool cpu_active(unsigned int cpu)
1288 {
1289 	return cpu == 0;
1290 }
1291 
cpu_dying(unsigned int cpu)1292 static __always_inline bool cpu_dying(unsigned int cpu)
1293 {
1294 	return false;
1295 }
1296 
1297 #endif /* NR_CPUS > 1 */
1298 
1299 #define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))
1300 
1301 #if NR_CPUS <= BITS_PER_LONG
1302 #define CPU_BITS_ALL						\
1303 {								\
1304 	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
1305 }
1306 
1307 #else /* NR_CPUS > BITS_PER_LONG */
1308 
1309 #define CPU_BITS_ALL						\
1310 {								\
1311 	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,		\
1312 	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
1313 }
1314 #endif /* NR_CPUS > BITS_PER_LONG */
1315 
1316 /**
1317  * cpumap_print_to_pagebuf  - copies the cpumask into the buffer either
1318  *	as comma-separated list of cpus or hex values of cpumask
1319  * @list: indicates whether the cpumap must be list
1320  * @mask: the cpumask to copy
1321  * @buf: the buffer to copy into
1322  *
1323  * Return: the length of the (null-terminated) @buf string, zero if
1324  * nothing is copied.
1325  */
1326 static __always_inline ssize_t
cpumap_print_to_pagebuf(bool list,char * buf,const struct cpumask * mask)1327 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
1328 {
1329 	return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
1330 				      nr_cpu_ids);
1331 }
1332 
1333 /**
1334  * cpumap_print_bitmask_to_buf  - copies the cpumask into the buffer as
1335  *	hex values of cpumask
1336  *
1337  * @buf: the buffer to copy into
1338  * @mask: the cpumask to copy
1339  * @off: in the string from which we are copying, we copy to @buf
1340  * @count: the maximum number of bytes to print
1341  *
1342  * The function prints the cpumask into the buffer as hex values of
1343  * cpumask; Typically used by bin_attribute to export cpumask bitmask
1344  * ABI.
1345  *
1346  * Return: the length of how many bytes have been copied, excluding
1347  * terminating '\0'.
1348  */
1349 static __always_inline
cpumap_print_bitmask_to_buf(char * buf,const struct cpumask * mask,loff_t off,size_t count)1350 ssize_t cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask,
1351 				    loff_t off, size_t count)
1352 {
1353 	return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask),
1354 				   nr_cpu_ids, off, count) - 1;
1355 }
1356 
1357 /**
1358  * cpumap_print_list_to_buf  - copies the cpumask into the buffer as
1359  *	comma-separated list of cpus
1360  * @buf: the buffer to copy into
1361  * @mask: the cpumask to copy
1362  * @off: in the string from which we are copying, we copy to @buf
1363  * @count: the maximum number of bytes to print
1364  *
1365  * Everything is same with the above cpumap_print_bitmask_to_buf()
1366  * except the print format.
1367  *
1368  * Return: the length of how many bytes have been copied, excluding
1369  * terminating '\0'.
1370  */
1371 static __always_inline
cpumap_print_list_to_buf(char * buf,const struct cpumask * mask,loff_t off,size_t count)1372 ssize_t cpumap_print_list_to_buf(char *buf, const struct cpumask *mask,
1373 				 loff_t off, size_t count)
1374 {
1375 	return bitmap_print_list_to_buf(buf, cpumask_bits(mask),
1376 				   nr_cpu_ids, off, count) - 1;
1377 }
1378 
1379 #if NR_CPUS <= BITS_PER_LONG
1380 #define CPU_MASK_ALL							\
1381 (cpumask_t) { {								\
1382 	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
1383 } }
1384 #else
1385 #define CPU_MASK_ALL							\
1386 (cpumask_t) { {								\
1387 	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,			\
1388 	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
1389 } }
1390 #endif /* NR_CPUS > BITS_PER_LONG */
1391 
1392 #define CPU_MASK_NONE							\
1393 (cpumask_t) { {								\
1394 	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  0UL				\
1395 } }
1396 
1397 #define CPU_MASK_CPU0							\
1398 (cpumask_t) { {								\
1399 	[0] =  1UL							\
1400 } }
1401 
1402 /*
1403  * Provide a valid theoretical max size for cpumap and cpulist sysfs files
1404  * to avoid breaking userspace which may allocate a buffer based on the size
1405  * reported by e.g. fstat.
1406  *
1407  * for cpumap NR_CPUS * 9/32 - 1 should be an exact length.
1408  *
1409  * For cpulist 7 is (ceil(log10(NR_CPUS)) + 1) allowing for NR_CPUS to be up
1410  * to 2 orders of magnitude larger than 8192. And then we divide by 2 to
1411  * cover a worst-case of every other cpu being on one of two nodes for a
1412  * very large NR_CPUS.
1413  *
1414  *  Use PAGE_SIZE as a minimum for smaller configurations while avoiding
1415  *  unsigned comparison to -1.
1416  */
1417 #define CPUMAP_FILE_MAX_BYTES  (((NR_CPUS * 9)/32 > PAGE_SIZE) \
1418 					? (NR_CPUS * 9)/32 - 1 : PAGE_SIZE)
1419 #define CPULIST_FILE_MAX_BYTES  (((NR_CPUS * 7)/2 > PAGE_SIZE) ? (NR_CPUS * 7)/2 : PAGE_SIZE)
1420 
1421 #endif /* __LINUX_CPUMASK_H */
1422