summaryrefslogtreecommitdiff
path: root/include/linux/cpumask.h
blob: e8ad12b5b9d235782ea1fd33b575dc665914d32e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_CPUMASK_H
#define __LINUX_CPUMASK_H

/*
 * Cpumasks provide a bitmap suitable for representing the
 * set of CPU's in a system, one bit position per CPU number.  In general,
 * only nr_cpu_ids (<= NR_CPUS) bits are valid.
 */
#include <linux/kernel.h>
#include <linux/threads.h>
#include <linux/bitmap.h>
#include <linux/atomic.h>
#include <linux/bug.h>
#include <linux/gfp_types.h>
#include <linux/numa.h>

/* Don't assign or return these: may not be this big! */
typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;

/**
 * cpumask_bits - get the bits in a cpumask
 * @maskp: the struct cpumask *
 *
 * You should only assume nr_cpu_ids bits of this mask are valid.  This is
 * a macro so it's const-correct.
 */
#define cpumask_bits(maskp) ((maskp)->bits)

/**
 * cpumask_pr_args - printf args to output a cpumask
 * @maskp: cpumask to be printed
 *
 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
 */
#define cpumask_pr_args(maskp)		nr_cpu_ids, cpumask_bits(maskp)

#if NR_CPUS == 1
#define nr_cpu_ids		1U
#else
extern unsigned int nr_cpu_ids;
#endif

#ifdef CONFIG_CPUMASK_OFFSTACK
/* Assuming NR_CPUS is huge, a runtime limit is more efficient.  Also,
 * not all bits may be allocated. */
#define nr_cpumask_bits	nr_cpu_ids
#else
#define nr_cpumask_bits	((unsigned int)NR_CPUS)
#endif

/*
 * The following particular system cpumasks and operations manage
 * possible, present, active and online cpus.
 *
 *     cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
 *     cpu_present_mask - has bit 'cpu' set iff cpu is populated
 *     cpu_online_mask  - has bit 'cpu' set iff cpu available to scheduler
 *     cpu_active_mask  - has bit 'cpu' set iff cpu available to migration
 *
 *  If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
 *
 *  The cpu_possible_mask is fixed at boot time, as the set of CPU id's
 *  that it is possible might ever be plugged in at anytime during the
 *  life of that system boot.  The cpu_present_mask is dynamic(*),
 *  representing which CPUs are currently plugged in.  And
 *  cpu_online_mask is the dynamic subset of cpu_present_mask,
 *  indicating those CPUs available for scheduling.
 *
 *  If HOTPLUG is enabled, then cpu_possible_mask is forced to have
 *  all NR_CPUS bits set, otherwise it is just the set of CPUs that
 *  ACPI reports present at boot.
 *
 *  If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
 *  depending on what ACPI reports as currently plugged in, otherwise
 *  cpu_present_mask is just a copy of cpu_possible_mask.
 *
 *  (*) Well, cpu_present_mask is dynamic in the hotplug case.  If not
 *      hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
 *
 * Subtleties:
 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
 *    assumption that their single CPU is online.  The UP
 *    cpu_{online,possible,present}_masks are placebos.  Changing them
 *    will have no useful affect on the following num_*_cpus()
 *    and cpu_*() macros in the UP case.  This ugliness is a UP
 *    optimization - don't waste any instructions or memory references
 *    asking if you're online or how many CPUs there are if there is
 *    only one CPU.
 */

extern struct cpumask __cpu_possible_mask;
extern struct cpumask __cpu_online_mask;
extern struct cpumask __cpu_present_mask;
extern struct cpumask __cpu_active_mask;
extern struct cpumask __cpu_dying_mask;
#define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask)
#define cpu_online_mask   ((const struct cpumask *)&__cpu_online_mask)
#define cpu_present_mask  ((const struct cpumask *)&__cpu_present_mask)
#define cpu_active_mask   ((const struct cpumask *)&__cpu_active_mask)
#define cpu_dying_mask    ((const struct cpumask *)&__cpu_dying_mask)

extern atomic_t __num_online_cpus;

extern cpumask_t cpus_booted_once_mask;

static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits)
{
#ifdef CONFIG_DEBUG_PER_CPU_MAPS
	WARN_ON_ONCE(cpu >= bits);
#endif /* CONFIG_DEBUG_PER_CPU_MAPS */
}

/* verify cpu argument to cpumask_* operators */
static __always_inline unsigned int cpumask_check(unsigned int cpu)
{
	cpu_max_bits_warn(cpu, nr_cpumask_bits);
	return cpu;
}

/**
 * cpumask_first - get the first cpu in a cpumask
 * @srcp: the cpumask pointer
 *
 * Returns >= nr_cpu_ids if no cpus set.
 */
static inline unsigned int cpumask_first(const struct cpumask *srcp)
{
	return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
}

/**
 * cpumask_first_zero - get the first unset cpu in a cpumask
 * @srcp: the cpumask pointer
 *
 * Returns >= nr_cpu_ids if all cpus are set.
 */
static inline unsigned int cpumask_first_zero(const struct cpumask *srcp)
{
	return find_first_zero_bit(cpumask_bits(srcp), nr_cpumask_bits);
}

/**
 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
 * @src1p: the first input
 * @src2p: the second input
 *
 * Returns >= nr_cpu_ids if no cpus set in both.  See also cpumask_next_and().
 */
static inline
unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2)
{
	return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), nr_cpumask_bits);
}

/**
 * cpumask_last - get the last CPU in a cpumask
 * @srcp:	- the cpumask pointer
 *
 * Returns	>= nr_cpumask_bits if no CPUs set.
 */
static inline unsigned int cpumask_last(const struct cpumask *srcp)
{
	return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits);
}

/**
 * cpumask_next - get the next cpu in a cpumask
 * @n: the cpu prior to the place to search (ie. return will be > @n)
 * @srcp: the cpumask pointer
 *
 * Returns >= nr_cpu_ids if no further cpus set.
 */
static inline
unsigned int cpumask_next(int n, const struct cpumask *srcp)
{
	/* -1 is a legal arg here. */
	if (n != -1)
		cpumask_check(n);
	return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1);
}

/**
 * cpumask_next_zero - get the next unset cpu in a cpumask
 * @n: the cpu prior to the place to search (ie. return will be > @n)
 * @srcp: the cpumask pointer
 *
 * Returns >= nr_cpu_ids if no further cpus unset.
 */
static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
{
	/* -1 is a legal arg here. */
	if (n != -1)
		cpumask_check(n);
	return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
}

#if NR_CPUS == 1
/* Uniprocessor: there is only one valid CPU */
static inline unsigned int cpumask_local_spread(unsigned int i, int node)
{
	return 0;
}

static inline unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
						      const struct cpumask *src2p)
{
	return cpumask_first_and(src1p, src2p);
}

static inline unsigned int cpumask_any_distribute(const struct cpumask *srcp)
{
	return cpumask_first(srcp);
}
#else
unsigned int cpumask_local_spread(unsigned int i, int node);
unsigned int cpumask_any_and_distribute(const struct cpumask *src1p,
			       const struct cpumask *src2p);
unsigned int cpumask_any_distribute(const struct cpumask *srcp);
#endif /* NR_CPUS */

/**
 * cpumask_next_and - get the next cpu in *src1p & *src2p
 * @n: the cpu prior to the place to search (ie. return will be > @n)
 * @src1p: the first cpumask pointer
 * @src2p: the second cpumask pointer
 *
 * Returns >= nr_cpu_ids if no further cpus set in both.
 */
static inline
unsigned int cpumask_next_and(int n, const struct cpumask *src1p,
		     const struct cpumask *src2p)
{
	/* -1 is a legal arg here. */
	if (n != -1)
		cpumask_check(n);
	return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p),
		nr_cpumask_bits, n + 1);
}

/**
 * for_each_cpu - iterate over every cpu in a mask
 * @cpu: the (optionally unsigned) integer iterator
 * @mask: the cpumask pointer
 *
 * After the loop, cpu is >= nr_cpu_ids.
 */
#define for_each_cpu(cpu, mask)				\
	for ((cpu) = -1;				\
		(cpu) = cpumask_next((cpu), (mask)),	\
		(cpu) < nr_cpu_ids;)

/**
 * for_each_cpu_not - iterate over every cpu in a complemented mask
 * @cpu: the (optionally unsigned) integer iterator
 * @mask: the cpumask pointer
 *
 * After the loop, cpu is >= nr_cpu_ids.
 */
#define for_each_cpu_not(cpu, mask)				\
	for ((cpu) = -1;					\
		(cpu) = cpumask_next_zero((cpu), (mask)),	\
		(cpu) < nr_cpu_ids;)

#if NR_CPUS == 1
static inline
unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap)
{
	cpumask_check(start);
	if (n != -1)
		cpumask_check(n);

	/*
	 * Return the first available CPU when wrapping, or when starting before cpu0,
	 * since there is only one valid option.
	 */
	if (wrap && n >= 0)
		return nr_cpumask_bits;

	return cpumask_first(mask);
}
#else
unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap);
#endif

/**
 * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location
 * @cpu: the (optionally unsigned) integer iterator
 * @mask: the cpumask pointer
 * @start: the start location
 *
 * The implementation does not assume any bit in @mask is set (including @start).
 *
 * After the loop, cpu is >= nr_cpu_ids.
 */
#define for_each_cpu_wrap(cpu, mask, start)					\
	for ((cpu) = cpumask_next_wrap((start)-1, (mask), (start), false);	\
	     (cpu) < nr_cpumask_bits;						\
	     (cpu) = cpumask_next_wrap((cpu), (mask), (start), true))

/**
 * for_each_cpu_and - iterate over every cpu in both masks
 * @cpu: the (optionally unsigned) integer iterator
 * @mask1: the first cpumask pointer
 * @mask2: the second cpumask pointer
 *
 * This saves a temporary CPU mask in many places.  It is equivalent to:
 *	struct cpumask tmp;
 *	cpumask_and(&tmp, &mask1, &mask2);
 *	for_each_cpu(cpu, &tmp)
 *		...
 *
 * After the loop, cpu is >= nr_cpu_ids.
 */
#define for_each_cpu_and(cpu, mask1, mask2)				\
	for ((cpu) = -1;						\
		(cpu) = cpumask_next_and((cpu), (mask1), (mask2)),	\
		(cpu) < nr_cpu_ids;)

/**
 * cpumask_any_but - return a "random" in a cpumask, but not this one.
 * @mask: the cpumask to search
 * @cpu: the cpu to ignore.
 *
 * Often used to find any cpu but smp_processor_id() in a mask.
 * Returns >= nr_cpu_ids if no cpus set.
 */
static inline
unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu)
{
	unsigned int i;

	cpumask_check(cpu);
	for_each_cpu(i, mask)
		if (i != cpu)
			break;
	return i;
}

#define CPU_BITS_NONE						\
{								\
	[0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL			\
}

#define CPU_BITS_CPU0						\
{								\
	[0] =  1UL						\
}

/**
 * cpumask_set_cpu - set a cpu in a cpumask
 * @cpu: cpu number (< nr_cpu_ids)
 * @dstp: the cpumask pointer
 */
static __always_inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
{
	set_bit(cpumask_check(cpu), cpumask_bits(dstp));
}

static __always_inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
{
	__set_bit(cpumask_check(cpu), cpumask_bits(dstp));
}


/**
 * cpumask_clear_cpu - clear a cpu in a cpumask
 * @cpu: cpu number (< nr_cpu_ids)
 * @dstp: the cpumask pointer
 */
static __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
{
	clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
}

static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp)
{
	__clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
}

/**
 * cpumask_test_cpu - test for a cpu in a cpumask
 * @cpu: cpu number (< nr_cpu_ids)
 * @cpumask: the cpumask pointer
 *
 * Returns true if @cpu is set in @cpumask, else returns false
 */
static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
{
	return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
}

/**
 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
 * @cpu: cpu number (< nr_cpu_ids)
 * @cpumask: the cpumask pointer
 *
 * Returns true if @cpu is set in old bitmap of @cpumask, else returns false
 *
 * test_and_set_bit wrapper for cpumasks.
 */
static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
{
	return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
}

/**
 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
 * @cpu: cpu number (< nr_cpu_ids)
 * @cpumask: the cpumask pointer
 *
 * Returns true if @cpu is set in old bitmap of @cpumask, else returns false
 *
 * test_and_clear_bit wrapper for cpumasks.
 */
static __always_inline bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
{
	return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
}

/**
 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
 * @dstp: the cpumask pointer
 */
static inline void cpumask_setall(struct cpumask *dstp)
{
	bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
}

/**
 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
 * @dstp: the cpumask pointer
 */
static inline void cpumask_clear(struct cpumask *dstp)
{
	bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits);
}

/**
 * cpumask_and - *dstp = *src1p & *src2p
 * @dstp: the cpumask result
 * @src1p: the first input
 * @src2p: the second input
 *
 * If *@dstp is empty, returns false, else returns true
 */
static inline bool cpumask_and(struct cpumask *dstp,
			       const struct cpumask *src1p,
			       const struct cpumask *src2p)
{
	return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
				       cpumask_bits(src2p), nr_cpumask_bits);
}

/**
 * cpumask_or - *dstp = *src1p | *src2p
 * @dstp: the cpumask result
 * @src1p: the first input
 * @src2p: the second input
 */
static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
			      const struct cpumask *src2p)
{
	bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
				      cpumask_bits(src2p), nr_cpumask_bits);
}

/**
 * cpumask_xor - *dstp = *src1p ^ *src2p
 * @dstp: the cpumask result
 * @src1p: the first input
 * @src2p: the second input
 */
static inline void cpumask_xor(struct cpumask *dstp,
			       const struct cpumask *src1p,
			       const struct cpumask *src2p)
{
	bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
				       cpumask_bits(src2p), nr_cpumask_bits);
}

/**
 * cpumask_andnot - *dstp = *src1p & ~*src2p
 * @dstp: the cpumask result
 * @src1p: the first input
 * @src2p: the second input
 *
 * If *@dstp is empty, returns false, else returns true
 */
static inline bool cpumask_andnot(struct cpumask *dstp,
				  const struct cpumask *src1p,
				  const struct cpumask *src2p)
{
	return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
					  cpumask_bits(src2p), nr_cpumask_bits);
}

/**
 * cpumask_complement - *dstp = ~*srcp
 * @dstp: the cpumask result
 * @srcp: the input to invert
 */
static inline void cpumask_complement(struct cpumask *dstp,
				      const struct cpumask *srcp)
{
	bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp),
					      nr_cpumask_bits);
}

/**
 * cpumask_equal - *src1p == *src2p
 * @src1p: the first input
 * @src2p: the second input
 */
static inline bool cpumask_equal(const struct cpumask *src1p,
				const struct cpumask *src2p)
{
	return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
						 nr_cpumask_bits);
}

/**
 * cpumask_or_equal - *src1p | *src2p == *src3p
 * @src1p: the first input
 * @src2p: the second input
 * @src3p: the third input
 */
static inline bool cpumask_or_equal(const struct cpumask *src1p,
				    const struct cpumask *src2p,
				    const struct cpumask *src3p)
{
	return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p),
			       cpumask_bits(src3p), nr_cpumask_bits);
}

/**
 * cpumask_intersects - (*src1p & *src2p) != 0
 * @src1p: the first input
 * @src2p: the second input
 */
static inline bool cpumask_intersects(const struct cpumask *src1p,
				     const struct cpumask *src2p)
{
	return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
						      nr_cpumask_bits);
}

/**
 * cpumask_subset - (*src1p & ~*src2p) == 0
 * @src1p: the first input
 * @src2p: the second input
 *
 * Returns true if *@src1p is a subset of *@src2p, else returns false
 */
static inline bool cpumask_subset(const struct cpumask *src1p,
				 const struct cpumask *src2p)
{
	return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
						  nr_cpumask_bits);
}

/**
 * cpumask_empty - *srcp == 0
 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
 */
static inline bool cpumask_empty(const struct cpumask *srcp)
{
	return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits);
}

/**
 * cpumask_full - *srcp == 0xFFFFFFFF...
 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
 */
static inline bool cpumask_full(const struct cpumask *srcp)
{
	return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
}

/**
 * cpumask_weight - Count of bits in *srcp
 * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
 */
static inline unsigned int cpumask_weight(const struct cpumask *srcp)
{
	return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits);
}

/**
 * cpumask_shift_right - *dstp = *srcp >> n
 * @dstp: the cpumask result
 * @srcp: the input to shift
 * @n: the number of bits to shift by
 */
static inline void cpumask_shift_right(struct cpumask *dstp,
				       const struct cpumask *srcp, int n)
{
	bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
					       nr_cpumask_bits);
}

/**
 * cpumask_shift_left - *dstp = *srcp << n
 * @dstp: the cpumask result
 * @srcp: the input to shift
 * @n: the number of bits to shift by
 */
static inline void cpumask_shift_left(struct cpumask *dstp,
				      const struct cpumask *srcp, int n)
{
	bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
					      nr_cpumask_bits);
}

/**
 * cpumask_copy - *dstp = *srcp
 * @dstp: the result
 * @srcp: the input cpumask
 */
static inline void cpumask_copy(struct cpumask *dstp,
				const struct cpumask *srcp)
{
	bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits);
}

/**
 * cpumask_any - pick a "random" cpu from *srcp
 * @srcp: the input cpumask
 *
 * Returns >= nr_cpu_ids if no cpus set.
 */
#define cpumask_any(srcp) cpumask_first(srcp)

/**
 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
 * @mask1: the first input cpumask
 * @mask2: the second input cpumask
 *
 * Returns >= nr_cpu_ids if no cpus set.
 */
#define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))

/**
 * cpumask_of - the cpumask containing just a given cpu
 * @cpu: the cpu (<= nr_cpu_ids)
 */
#define cpumask_of(cpu) (get_cpu_mask(cpu))

/**
 * cpumask_parse_user - extract a cpumask from a user string
 * @buf: the buffer to extract from
 * @len: the length of the buffer
 * @dstp: the cpumask to set.
 *
 * Returns -errno, or 0 for success.
 */
static inline int cpumask_parse_user(const char __user *buf, int len,
				     struct cpumask *dstp)
{
	return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
}

/**
 * cpumask_parselist_user - extract a cpumask from a user string
 * @buf: the buffer to extract from
 * @len: the length of the buffer
 * @dstp: the cpumask to set.
 *
 * Returns -errno, or 0 for success.
 */
static inline int cpumask_parselist_user(const char __user *buf, int len,
				     struct cpumask *dstp)
{
	return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
				     nr_cpumask_bits);
}

/**
 * cpumask_parse - extract a cpumask from a string
 * @buf: the buffer to extract from
 * @dstp: the cpumask to set.
 *
 * Returns -errno, or 0 for success.
 */
static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
{
	return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits);
}

/**
 * cpulist_parse - extract a cpumask from a user string of ranges
 * @buf: the buffer to extract from
 * @dstp: the cpumask to set.
 *
 * Returns -errno, or 0 for success.
 */
static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
{
	return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits);
}

/**
 * cpumask_size - size to allocate for a 'struct cpumask' in bytes
 */
static inline unsigned int cpumask_size(void)
{
	return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
}

/*
 * cpumask_var_t: struct cpumask for stack usage.
 *
 * Oh, the wicked games we play!  In order to make kernel coding a
 * little more difficult, we typedef cpumask_var_t to an array or a
 * pointer: doing &mask on an array is a noop, so it still works.
 *
 * ie.
 *	cpumask_var_t tmpmask;
 *	if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
 *		return -ENOMEM;
 *
 *	  ... use 'tmpmask' like a normal struct cpumask * ...
 *
 *	free_cpumask_var(tmpmask);
 *
 *
 * However, one notable exception is there. alloc_cpumask_var() allocates
 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has
 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t.
 *
 *	cpumask_var_t tmpmask;
 *	if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
 *		return -ENOMEM;
 *
 *	var = *tmpmask;
 *
 * This code makes NR_CPUS length memcopy and brings to a memory corruption.
 * cpumask_copy() provide safe copy functionality.
 *
 * Note that there is another evil here: If you define a cpumask_var_t
 * as a percpu variable then the way to obtain the address of the cpumask
 * structure differently influences what this_cpu_* operation needs to be
 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use
 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the
 * other type of cpumask_var_t implementation is configured.
 *
 * Please also note that __cpumask_var_read_mostly can be used to declare
 * a cpumask_var_t variable itself (not its content) as read mostly.
 */
#ifdef CONFIG_CPUMASK_OFFSTACK
typedef struct cpumask *cpumask_var_t;

#define this_cpu_cpumask_var_ptr(x)	this_cpu_read(x)
#define __cpumask_var_read_mostly	__read_mostly

bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);

static inline
bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node)
{
	return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node);
}

/**
 * alloc_cpumask_var - allocate a struct cpumask
 * @mask: pointer to cpumask_var_t where the cpumask is returned
 * @flags: GFP_ flags
 *
 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is
 * a nop returning a constant 1 (in <linux/cpumask.h>).
 *
 * See alloc_cpumask_var_node.
 */
static inline
bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
{
	return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE);
}

static inline
bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
{
	return alloc_cpumask_var(mask, flags | __GFP_ZERO);
}

void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
void free_cpumask_var(cpumask_var_t mask);
void free_bootmem_cpumask_var(cpumask_var_t mask);

static inline bool cpumask_available(cpumask_var_t mask)
{
	return mask != NULL;
}

#else
typedef struct cpumask cpumask_var_t[1];

#define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
#define __cpumask_var_read_mostly

static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
{
	return true;
}

static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
					  int node)
{
	return true;
}

static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
{
	cpumask_clear(*mask);
	return true;
}

static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
					  int node)
{
	cpumask_clear(*mask);
	return true;
}

static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
{
}

static inline void free_cpumask_var(cpumask_var_t mask)
{
}

static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
{
}

static inline bool cpumask_available(cpumask_var_t mask)
{
	return true;
}
#endif /* CONFIG_CPUMASK_OFFSTACK */

/* It's common to want to use cpu_all_mask in struct member initializers,
 * so it has to refer to an address rather than a pointer. */
extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
#define cpu_all_mask to_cpumask(cpu_all_bits)

/* First bits of cpu_bit_bitmap are in fact unset. */
#define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])

#if NR_CPUS == 1
/* Uniprocessor: the possible/online/present masks are always "1" */
#define for_each_possible_cpu(cpu)	for ((cpu) = 0; (cpu) < 1; (cpu)++)
#define for_each_online_cpu(cpu)	for ((cpu) = 0; (cpu) < 1; (cpu)++)
#define for_each_present_cpu(cpu)	for ((cpu) = 0; (cpu) < 1; (cpu)++)
#else
#define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
#define for_each_online_cpu(cpu)   for_each_cpu((cpu), cpu_online_mask)
#define for_each_present_cpu(cpu)  for_each_cpu((cpu), cpu_present_mask)
#endif

/* Wrappers for arch boot code to manipulate normally-constant masks */
void init_cpu_present(const struct cpumask *src);
void init_cpu_possible(const struct cpumask *src);
void init_cpu_online(const struct cpumask *src);

static inline void reset_cpu_possible_mask(void)
{
	bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS);
}

static inline void
set_cpu_possible(unsigned int cpu, bool possible)
{
	if (possible)
		cpumask_set_cpu(cpu, &__cpu_possible_mask);
	else
		cpumask_clear_cpu(cpu, &__cpu_possible_mask);
}

static inline void
set_cpu_present(unsigned int cpu, bool present)
{
	if (present)
		cpumask_set_cpu(cpu, &__cpu_present_mask);
	else
		cpumask_clear_cpu(cpu, &__cpu_present_mask);
}

void set_cpu_online(unsigned int cpu, bool online);

static inline void
set_cpu_active(unsigned int cpu, bool active)
{
	if (active)
		cpumask_set_cpu(cpu, &__cpu_active_mask);
	else
		cpumask_clear_cpu(cpu, &__cpu_active_mask);
}

static inline void
set_cpu_dying(unsigned int cpu, bool dying)
{
	if (dying)
		cpumask_set_cpu(cpu, &__cpu_dying_mask);
	else
		cpumask_clear_cpu(cpu, &__cpu_dying_mask);
}

/**
 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
 * @bitmap: the bitmap
 *
 * There are a few places where cpumask_var_t isn't appropriate and
 * static cpumasks must be used (eg. very early boot), yet we don't
 * expose the definition of 'struct cpumask'.
 *
 * This does the conversion, and can be used as a constant initializer.
 */
#define to_cpumask(bitmap)						\
	((struct cpumask *)(1 ? (bitmap)				\
			    : (void *)sizeof(__check_is_bitmap(bitmap))))

static inline int __check_is_bitmap(const unsigned long *bitmap)
{
	return 1;
}

/*
 * Special-case data structure for "single bit set only" constant CPU masks.
 *
 * We pre-generate all the 64 (or 32) possible bit positions, with enough
 * padding to the left and the right, and return the constant pointer
 * appropriately offset.
 */
extern const unsigned long
	cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];

static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
{
	const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
	p -= cpu / BITS_PER_LONG;
	return to_cpumask(p);
}

#if NR_CPUS > 1
/**
 * num_online_cpus() - Read the number of online CPUs
 *
 * Despite the fact that __num_online_cpus is of type atomic_t, this
 * interface gives only a momentary snapshot and is not protected against
 * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held
 * region.
 */
static inline unsigned int num_online_cpus(void)
{
	return atomic_read(&__num_online_cpus);
}
#define num_possible_cpus()	cpumask_weight(cpu_possible_mask)
#define num_present_cpus()	cpumask_weight(cpu_present_mask)
#define num_active_cpus()	cpumask_weight(cpu_active_mask)

static inline bool cpu_online(unsigned int cpu)
{
	return cpumask_test_cpu(cpu, cpu_online_mask);
}

static inline bool cpu_possible(unsigned int cpu)
{
	return cpumask_test_cpu(cpu, cpu_possible_mask);
}

static inline bool cpu_present(unsigned int cpu)
{
	return cpumask_test_cpu(cpu, cpu_present_mask);
}

static inline bool cpu_active(unsigned int cpu)
{
	return cpumask_test_cpu(cpu, cpu_active_mask);
}

static inline bool cpu_dying(unsigned int cpu)
{
	return cpumask_test_cpu(cpu, cpu_dying_mask);
}

#else

#define num_online_cpus()	1U
#define num_possible_cpus()	1U
#define num_present_cpus()	1U
#define num_active_cpus()	1U

static inline bool cpu_online(unsigned int cpu)
{
	return cpu == 0;
}

static inline bool cpu_possible(unsigned int cpu)
{
	return cpu == 0;
}

static inline bool cpu_present(unsigned int cpu)
{
	return cpu == 0;
}

static inline bool cpu_active(unsigned int cpu)
{
	return cpu == 0;
}

static inline bool cpu_dying(unsigned int cpu)
{
	return false;
}

#endif /* NR_CPUS > 1 */

#define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))

#if NR_CPUS <= BITS_PER_LONG
#define CPU_BITS_ALL						\
{								\
	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
}

#else /* NR_CPUS > BITS_PER_LONG */

#define CPU_BITS_ALL						\
{								\
	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,		\
	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
}
#endif /* NR_CPUS > BITS_PER_LONG */

/**
 * cpumap_print_to_pagebuf  - copies the cpumask into the buffer either
 *	as comma-separated list of cpus or hex values of cpumask
 * @list: indicates whether the cpumap must be list
 * @mask: the cpumask to copy
 * @buf: the buffer to copy into
 *
 * Returns the length of the (null-terminated) @buf string, zero if
 * nothing is copied.
 */
static inline ssize_t
cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
{
	return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
				      nr_cpu_ids);
}

/**
 * cpumap_print_bitmask_to_buf  - copies the cpumask into the buffer as
 *	hex values of cpumask
 *
 * @buf: the buffer to copy into
 * @mask: the cpumask to copy
 * @off: in the string from which we are copying, we copy to @buf
 * @count: the maximum number of bytes to print
 *
 * The function prints the cpumask into the buffer as hex values of
 * cpumask; Typically used by bin_attribute to export cpumask bitmask
 * ABI.
 *
 * Returns the length of how many bytes have been copied, excluding
 * terminating '\0'.
 */
static inline ssize_t
cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask,
		loff_t off, size_t count)
{
	return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask),
				   nr_cpu_ids, off, count) - 1;
}

/**
 * cpumap_print_list_to_buf  - copies the cpumask into the buffer as
 *	comma-separated list of cpus
 *
 * Everything is same with the above cpumap_print_bitmask_to_buf()
 * except the print format.
 */
static inline ssize_t
cpumap_print_list_to_buf(char *buf, const struct cpumask *mask,
		loff_t off, size_t count)
{
	return bitmap_print_list_to_buf(buf, cpumask_bits(mask),
				   nr_cpu_ids, off, count) - 1;
}

#if NR_CPUS <= BITS_PER_LONG
#define CPU_MASK_ALL							\
(cpumask_t) { {								\
	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
} }
#else
#define CPU_MASK_ALL							\
(cpumask_t) { {								\
	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,			\
	[BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS)	\
} }
#endif /* NR_CPUS > BITS_PER_LONG */

#define CPU_MASK_NONE							\
(cpumask_t) { {								\
	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  0UL				\
} }

#define CPU_MASK_CPU0							\
(cpumask_t) { {								\
	[0] =  1UL							\
} }

/*
 * Provide a valid theoretical max size for cpumap and cpulist sysfs files
 * to avoid breaking userspace which may allocate a buffer based on the size
 * reported by e.g. fstat.
 *
 * for cpumap NR_CPUS * 9/32 - 1 should be an exact length.
 *
 * For cpulist 7 is (ceil(log10(NR_CPUS)) + 1) allowing for NR_CPUS to be up
 * to 2 orders of magnitude larger than 8192. And then we divide by 2 to
 * cover a worst-case of every other cpu being on one of two nodes for a
 * very large NR_CPUS.
 *
 *  Use PAGE_SIZE as a minimum for smaller configurations while avoiding
 *  unsigned comparison to -1.
 */
#define CPUMAP_FILE_MAX_BYTES  (((NR_CPUS * 9)/32 > PAGE_SIZE) \
					? (NR_CPUS * 9)/32 - 1 : PAGE_SIZE)
#define CPULIST_FILE_MAX_BYTES  (((NR_CPUS * 7)/2 > PAGE_SIZE) ? (NR_CPUS * 7)/2 : PAGE_SIZE)

#endif /* __LINUX_CPUMASK_H */