]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - include/linux/cpumask.h
powerpc/perf: Add thread IMC PMU support
[mirror_ubuntu-artful-kernel.git] / include / linux / cpumask.h
1 #ifndef __LINUX_CPUMASK_H
2 #define __LINUX_CPUMASK_H
3
4 /*
5 * Cpumasks provide a bitmap suitable for representing the
6 * set of CPU's in a system, one bit position per CPU number. In general,
7 * only nr_cpu_ids (<= NR_CPUS) bits are valid.
8 */
9 #include <linux/kernel.h>
10 #include <linux/threads.h>
11 #include <linux/bitmap.h>
12 #include <linux/bug.h>
13
14 /* Don't assign or return these: may not be this big! */
15 typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
16
17 /**
18 * cpumask_bits - get the bits in a cpumask
19 * @maskp: the struct cpumask *
20 *
21 * You should only assume nr_cpu_ids bits of this mask are valid. This is
22 * a macro so it's const-correct.
23 */
24 #define cpumask_bits(maskp) ((maskp)->bits)
25
26 /**
27 * cpumask_pr_args - printf args to output a cpumask
28 * @maskp: cpumask to be printed
29 *
30 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
31 */
32 #define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp)
33
34 #if NR_CPUS == 1
35 #define nr_cpu_ids 1
36 #else
37 extern int nr_cpu_ids;
38 #endif
39
40 #ifdef CONFIG_CPUMASK_OFFSTACK
41 /* Assuming NR_CPUS is huge, a runtime limit is more efficient. Also,
42 * not all bits may be allocated. */
43 #define nr_cpumask_bits ((unsigned int)nr_cpu_ids)
44 #else
45 #define nr_cpumask_bits ((unsigned int)NR_CPUS)
46 #endif
47
48 /*
49 * The following particular system cpumasks and operations manage
50 * possible, present, active and online cpus.
51 *
52 * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
53 * cpu_present_mask - has bit 'cpu' set iff cpu is populated
54 * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler
55 * cpu_active_mask - has bit 'cpu' set iff cpu available to migration
56 *
57 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
58 *
59 * The cpu_possible_mask is fixed at boot time, as the set of CPU id's
60 * that it is possible might ever be plugged in at anytime during the
61 * life of that system boot. The cpu_present_mask is dynamic(*),
62 * representing which CPUs are currently plugged in. And
63 * cpu_online_mask is the dynamic subset of cpu_present_mask,
64 * indicating those CPUs available for scheduling.
65 *
66 * If HOTPLUG is enabled, then cpu_possible_mask is forced to have
67 * all NR_CPUS bits set, otherwise it is just the set of CPUs that
68 * ACPI reports present at boot.
69 *
70 * If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
71 * depending on what ACPI reports as currently plugged in, otherwise
72 * cpu_present_mask is just a copy of cpu_possible_mask.
73 *
74 * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not
75 * hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
76 *
77 * Subtleties:
78 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
79 * assumption that their single CPU is online. The UP
80 * cpu_{online,possible,present}_masks are placebos. Changing them
81 * will have no useful affect on the following num_*_cpus()
82 * and cpu_*() macros in the UP case. This ugliness is a UP
83 * optimization - don't waste any instructions or memory references
84 * asking if you're online or how many CPUs there are if there is
85 * only one CPU.
86 */
87
88 extern struct cpumask __cpu_possible_mask;
89 extern struct cpumask __cpu_online_mask;
90 extern struct cpumask __cpu_present_mask;
91 extern struct cpumask __cpu_active_mask;
92 #define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask)
93 #define cpu_online_mask ((const struct cpumask *)&__cpu_online_mask)
94 #define cpu_present_mask ((const struct cpumask *)&__cpu_present_mask)
95 #define cpu_active_mask ((const struct cpumask *)&__cpu_active_mask)
96
97 #if NR_CPUS > 1
98 #define num_online_cpus() cpumask_weight(cpu_online_mask)
99 #define num_possible_cpus() cpumask_weight(cpu_possible_mask)
100 #define num_present_cpus() cpumask_weight(cpu_present_mask)
101 #define num_active_cpus() cpumask_weight(cpu_active_mask)
102 #define cpu_online(cpu) cpumask_test_cpu((cpu), cpu_online_mask)
103 #define cpu_possible(cpu) cpumask_test_cpu((cpu), cpu_possible_mask)
104 #define cpu_present(cpu) cpumask_test_cpu((cpu), cpu_present_mask)
105 #define cpu_active(cpu) cpumask_test_cpu((cpu), cpu_active_mask)
106 #else
107 #define num_online_cpus() 1U
108 #define num_possible_cpus() 1U
109 #define num_present_cpus() 1U
110 #define num_active_cpus() 1U
111 #define cpu_online(cpu) ((cpu) == 0)
112 #define cpu_possible(cpu) ((cpu) == 0)
113 #define cpu_present(cpu) ((cpu) == 0)
114 #define cpu_active(cpu) ((cpu) == 0)
115 #endif
116
117 /* verify cpu argument to cpumask_* operators */
118 static inline unsigned int cpumask_check(unsigned int cpu)
119 {
120 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
121 WARN_ON_ONCE(cpu >= nr_cpumask_bits);
122 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
123 return cpu;
124 }
125
126 #if NR_CPUS == 1
127 /* Uniprocessor. Assume all masks are "1". */
128 static inline unsigned int cpumask_first(const struct cpumask *srcp)
129 {
130 return 0;
131 }
132
133 /* Valid inputs for n are -1 and 0. */
134 static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
135 {
136 return n+1;
137 }
138
139 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
140 {
141 return n+1;
142 }
143
144 static inline unsigned int cpumask_next_and(int n,
145 const struct cpumask *srcp,
146 const struct cpumask *andp)
147 {
148 return n+1;
149 }
150
151 /* cpu must be a valid cpu, ie 0, so there's no other choice. */
152 static inline unsigned int cpumask_any_but(const struct cpumask *mask,
153 unsigned int cpu)
154 {
155 return 1;
156 }
157
158 static inline unsigned int cpumask_local_spread(unsigned int i, int node)
159 {
160 return 0;
161 }
162
163 #define for_each_cpu(cpu, mask) \
164 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
165 #define for_each_cpu_not(cpu, mask) \
166 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
167 #define for_each_cpu_and(cpu, mask, and) \
168 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)and)
169 #else
170 /**
171 * cpumask_first - get the first cpu in a cpumask
172 * @srcp: the cpumask pointer
173 *
174 * Returns >= nr_cpu_ids if no cpus set.
175 */
176 static inline unsigned int cpumask_first(const struct cpumask *srcp)
177 {
178 return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
179 }
180
181 /**
182 * cpumask_next - get the next cpu in a cpumask
183 * @n: the cpu prior to the place to search (ie. return will be > @n)
184 * @srcp: the cpumask pointer
185 *
186 * Returns >= nr_cpu_ids if no further cpus set.
187 */
188 static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
189 {
190 /* -1 is a legal arg here. */
191 if (n != -1)
192 cpumask_check(n);
193 return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
194 }
195
196 /**
197 * cpumask_next_zero - get the next unset cpu in a cpumask
198 * @n: the cpu prior to the place to search (ie. return will be > @n)
199 * @srcp: the cpumask pointer
200 *
201 * Returns >= nr_cpu_ids if no further cpus unset.
202 */
203 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
204 {
205 /* -1 is a legal arg here. */
206 if (n != -1)
207 cpumask_check(n);
208 return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
209 }
210
211 int cpumask_next_and(int n, const struct cpumask *, const struct cpumask *);
212 int cpumask_any_but(const struct cpumask *mask, unsigned int cpu);
213 unsigned int cpumask_local_spread(unsigned int i, int node);
214
215 /**
216 * for_each_cpu - iterate over every cpu in a mask
217 * @cpu: the (optionally unsigned) integer iterator
218 * @mask: the cpumask pointer
219 *
220 * After the loop, cpu is >= nr_cpu_ids.
221 */
222 #define for_each_cpu(cpu, mask) \
223 for ((cpu) = -1; \
224 (cpu) = cpumask_next((cpu), (mask)), \
225 (cpu) < nr_cpu_ids;)
226
227 /**
228 * for_each_cpu_not - iterate over every cpu in a complemented mask
229 * @cpu: the (optionally unsigned) integer iterator
230 * @mask: the cpumask pointer
231 *
232 * After the loop, cpu is >= nr_cpu_ids.
233 */
234 #define for_each_cpu_not(cpu, mask) \
235 for ((cpu) = -1; \
236 (cpu) = cpumask_next_zero((cpu), (mask)), \
237 (cpu) < nr_cpu_ids;)
238
239 extern int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap);
240
241 /**
242 * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location
243 * @cpu: the (optionally unsigned) integer iterator
244 * @mask: the cpumask poiter
245 * @start: the start location
246 *
247 * The implementation does not assume any bit in @mask is set (including @start).
248 *
249 * After the loop, cpu is >= nr_cpu_ids.
250 */
251 #define for_each_cpu_wrap(cpu, mask, start) \
252 for ((cpu) = cpumask_next_wrap((start)-1, (mask), (start), false); \
253 (cpu) < nr_cpumask_bits; \
254 (cpu) = cpumask_next_wrap((cpu), (mask), (start), true))
255
256 /**
257 * for_each_cpu_and - iterate over every cpu in both masks
258 * @cpu: the (optionally unsigned) integer iterator
259 * @mask: the first cpumask pointer
260 * @and: the second cpumask pointer
261 *
262 * This saves a temporary CPU mask in many places. It is equivalent to:
263 * struct cpumask tmp;
264 * cpumask_and(&tmp, &mask, &and);
265 * for_each_cpu(cpu, &tmp)
266 * ...
267 *
268 * After the loop, cpu is >= nr_cpu_ids.
269 */
270 #define for_each_cpu_and(cpu, mask, and) \
271 for ((cpu) = -1; \
272 (cpu) = cpumask_next_and((cpu), (mask), (and)), \
273 (cpu) < nr_cpu_ids;)
274 #endif /* SMP */
275
276 #define CPU_BITS_NONE \
277 { \
278 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
279 }
280
281 #define CPU_BITS_CPU0 \
282 { \
283 [0] = 1UL \
284 }
285
286 /**
287 * cpumask_set_cpu - set a cpu in a cpumask
288 * @cpu: cpu number (< nr_cpu_ids)
289 * @dstp: the cpumask pointer
290 */
291 static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
292 {
293 set_bit(cpumask_check(cpu), cpumask_bits(dstp));
294 }
295
296 static inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
297 {
298 __set_bit(cpumask_check(cpu), cpumask_bits(dstp));
299 }
300
301
302 /**
303 * cpumask_clear_cpu - clear a cpu in a cpumask
304 * @cpu: cpu number (< nr_cpu_ids)
305 * @dstp: the cpumask pointer
306 */
307 static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
308 {
309 clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
310 }
311
312 static inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp)
313 {
314 __clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
315 }
316
317 /**
318 * cpumask_test_cpu - test for a cpu in a cpumask
319 * @cpu: cpu number (< nr_cpu_ids)
320 * @cpumask: the cpumask pointer
321 *
322 * Returns 1 if @cpu is set in @cpumask, else returns 0
323 */
324 static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
325 {
326 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
327 }
328
329 /**
330 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
331 * @cpu: cpu number (< nr_cpu_ids)
332 * @cpumask: the cpumask pointer
333 *
334 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
335 *
336 * test_and_set_bit wrapper for cpumasks.
337 */
338 static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
339 {
340 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
341 }
342
343 /**
344 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
345 * @cpu: cpu number (< nr_cpu_ids)
346 * @cpumask: the cpumask pointer
347 *
348 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
349 *
350 * test_and_clear_bit wrapper for cpumasks.
351 */
352 static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
353 {
354 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
355 }
356
357 /**
358 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
359 * @dstp: the cpumask pointer
360 */
361 static inline void cpumask_setall(struct cpumask *dstp)
362 {
363 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
364 }
365
366 /**
367 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
368 * @dstp: the cpumask pointer
369 */
370 static inline void cpumask_clear(struct cpumask *dstp)
371 {
372 bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits);
373 }
374
375 /**
376 * cpumask_and - *dstp = *src1p & *src2p
377 * @dstp: the cpumask result
378 * @src1p: the first input
379 * @src2p: the second input
380 *
381 * If *@dstp is empty, returns 0, else returns 1
382 */
383 static inline int cpumask_and(struct cpumask *dstp,
384 const struct cpumask *src1p,
385 const struct cpumask *src2p)
386 {
387 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
388 cpumask_bits(src2p), nr_cpumask_bits);
389 }
390
391 /**
392 * cpumask_or - *dstp = *src1p | *src2p
393 * @dstp: the cpumask result
394 * @src1p: the first input
395 * @src2p: the second input
396 */
397 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
398 const struct cpumask *src2p)
399 {
400 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
401 cpumask_bits(src2p), nr_cpumask_bits);
402 }
403
404 /**
405 * cpumask_xor - *dstp = *src1p ^ *src2p
406 * @dstp: the cpumask result
407 * @src1p: the first input
408 * @src2p: the second input
409 */
410 static inline void cpumask_xor(struct cpumask *dstp,
411 const struct cpumask *src1p,
412 const struct cpumask *src2p)
413 {
414 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
415 cpumask_bits(src2p), nr_cpumask_bits);
416 }
417
418 /**
419 * cpumask_andnot - *dstp = *src1p & ~*src2p
420 * @dstp: the cpumask result
421 * @src1p: the first input
422 * @src2p: the second input
423 *
424 * If *@dstp is empty, returns 0, else returns 1
425 */
426 static inline int cpumask_andnot(struct cpumask *dstp,
427 const struct cpumask *src1p,
428 const struct cpumask *src2p)
429 {
430 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
431 cpumask_bits(src2p), nr_cpumask_bits);
432 }
433
434 /**
435 * cpumask_complement - *dstp = ~*srcp
436 * @dstp: the cpumask result
437 * @srcp: the input to invert
438 */
439 static inline void cpumask_complement(struct cpumask *dstp,
440 const struct cpumask *srcp)
441 {
442 bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp),
443 nr_cpumask_bits);
444 }
445
446 /**
447 * cpumask_equal - *src1p == *src2p
448 * @src1p: the first input
449 * @src2p: the second input
450 */
451 static inline bool cpumask_equal(const struct cpumask *src1p,
452 const struct cpumask *src2p)
453 {
454 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
455 nr_cpumask_bits);
456 }
457
458 /**
459 * cpumask_intersects - (*src1p & *src2p) != 0
460 * @src1p: the first input
461 * @src2p: the second input
462 */
463 static inline bool cpumask_intersects(const struct cpumask *src1p,
464 const struct cpumask *src2p)
465 {
466 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
467 nr_cpumask_bits);
468 }
469
470 /**
471 * cpumask_subset - (*src1p & ~*src2p) == 0
472 * @src1p: the first input
473 * @src2p: the second input
474 *
475 * Returns 1 if *@src1p is a subset of *@src2p, else returns 0
476 */
477 static inline int cpumask_subset(const struct cpumask *src1p,
478 const struct cpumask *src2p)
479 {
480 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
481 nr_cpumask_bits);
482 }
483
484 /**
485 * cpumask_empty - *srcp == 0
486 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
487 */
488 static inline bool cpumask_empty(const struct cpumask *srcp)
489 {
490 return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits);
491 }
492
493 /**
494 * cpumask_full - *srcp == 0xFFFFFFFF...
495 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
496 */
497 static inline bool cpumask_full(const struct cpumask *srcp)
498 {
499 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
500 }
501
502 /**
503 * cpumask_weight - Count of bits in *srcp
504 * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
505 */
506 static inline unsigned int cpumask_weight(const struct cpumask *srcp)
507 {
508 return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits);
509 }
510
511 /**
512 * cpumask_shift_right - *dstp = *srcp >> n
513 * @dstp: the cpumask result
514 * @srcp: the input to shift
515 * @n: the number of bits to shift by
516 */
517 static inline void cpumask_shift_right(struct cpumask *dstp,
518 const struct cpumask *srcp, int n)
519 {
520 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
521 nr_cpumask_bits);
522 }
523
524 /**
525 * cpumask_shift_left - *dstp = *srcp << n
526 * @dstp: the cpumask result
527 * @srcp: the input to shift
528 * @n: the number of bits to shift by
529 */
530 static inline void cpumask_shift_left(struct cpumask *dstp,
531 const struct cpumask *srcp, int n)
532 {
533 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
534 nr_cpumask_bits);
535 }
536
537 /**
538 * cpumask_copy - *dstp = *srcp
539 * @dstp: the result
540 * @srcp: the input cpumask
541 */
542 static inline void cpumask_copy(struct cpumask *dstp,
543 const struct cpumask *srcp)
544 {
545 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits);
546 }
547
548 /**
549 * cpumask_any - pick a "random" cpu from *srcp
550 * @srcp: the input cpumask
551 *
552 * Returns >= nr_cpu_ids if no cpus set.
553 */
554 #define cpumask_any(srcp) cpumask_first(srcp)
555
556 /**
557 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
558 * @src1p: the first input
559 * @src2p: the second input
560 *
561 * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
562 */
563 #define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p))
564
565 /**
566 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
567 * @mask1: the first input cpumask
568 * @mask2: the second input cpumask
569 *
570 * Returns >= nr_cpu_ids if no cpus set.
571 */
572 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
573
574 /**
575 * cpumask_of - the cpumask containing just a given cpu
576 * @cpu: the cpu (<= nr_cpu_ids)
577 */
578 #define cpumask_of(cpu) (get_cpu_mask(cpu))
579
580 /**
581 * cpumask_parse_user - extract a cpumask from a user string
582 * @buf: the buffer to extract from
583 * @len: the length of the buffer
584 * @dstp: the cpumask to set.
585 *
586 * Returns -errno, or 0 for success.
587 */
588 static inline int cpumask_parse_user(const char __user *buf, int len,
589 struct cpumask *dstp)
590 {
591 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
592 }
593
594 /**
595 * cpumask_parselist_user - extract a cpumask from a user string
596 * @buf: the buffer to extract from
597 * @len: the length of the buffer
598 * @dstp: the cpumask to set.
599 *
600 * Returns -errno, or 0 for success.
601 */
602 static inline int cpumask_parselist_user(const char __user *buf, int len,
603 struct cpumask *dstp)
604 {
605 return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
606 nr_cpumask_bits);
607 }
608
609 /**
610 * cpumask_parse - extract a cpumask from a string
611 * @buf: the buffer to extract from
612 * @dstp: the cpumask to set.
613 *
614 * Returns -errno, or 0 for success.
615 */
616 static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
617 {
618 char *nl = strchr(buf, '\n');
619 unsigned int len = nl ? (unsigned int)(nl - buf) : strlen(buf);
620
621 return bitmap_parse(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
622 }
623
624 /**
625 * cpulist_parse - extract a cpumask from a user string of ranges
626 * @buf: the buffer to extract from
627 * @dstp: the cpumask to set.
628 *
629 * Returns -errno, or 0 for success.
630 */
631 static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
632 {
633 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits);
634 }
635
636 /**
637 * cpumask_size - size to allocate for a 'struct cpumask' in bytes
638 */
639 static inline size_t cpumask_size(void)
640 {
641 return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
642 }
643
644 /*
645 * cpumask_var_t: struct cpumask for stack usage.
646 *
647 * Oh, the wicked games we play! In order to make kernel coding a
648 * little more difficult, we typedef cpumask_var_t to an array or a
649 * pointer: doing &mask on an array is a noop, so it still works.
650 *
651 * ie.
652 * cpumask_var_t tmpmask;
653 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
654 * return -ENOMEM;
655 *
656 * ... use 'tmpmask' like a normal struct cpumask * ...
657 *
658 * free_cpumask_var(tmpmask);
659 *
660 *
661 * However, one notable exception is there. alloc_cpumask_var() allocates
662 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has
663 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t.
664 *
665 * cpumask_var_t tmpmask;
666 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
667 * return -ENOMEM;
668 *
669 * var = *tmpmask;
670 *
671 * This code makes NR_CPUS length memcopy and brings to a memory corruption.
672 * cpumask_copy() provide safe copy functionality.
673 *
674 * Note that there is another evil here: If you define a cpumask_var_t
675 * as a percpu variable then the way to obtain the address of the cpumask
676 * structure differently influences what this_cpu_* operation needs to be
677 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use
678 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the
679 * other type of cpumask_var_t implementation is configured.
680 *
681 * Please also note that __cpumask_var_read_mostly can be used to declare
682 * a cpumask_var_t variable itself (not its content) as read mostly.
683 */
684 #ifdef CONFIG_CPUMASK_OFFSTACK
685 typedef struct cpumask *cpumask_var_t;
686
687 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
688 #define __cpumask_var_read_mostly __read_mostly
689
690 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
691 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
692 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
693 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
694 void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
695 void free_cpumask_var(cpumask_var_t mask);
696 void free_bootmem_cpumask_var(cpumask_var_t mask);
697
698 static inline bool cpumask_available(cpumask_var_t mask)
699 {
700 return mask != NULL;
701 }
702
703 #else
704 typedef struct cpumask cpumask_var_t[1];
705
706 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
707 #define __cpumask_var_read_mostly
708
709 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
710 {
711 return true;
712 }
713
714 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
715 int node)
716 {
717 return true;
718 }
719
720 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
721 {
722 cpumask_clear(*mask);
723 return true;
724 }
725
726 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
727 int node)
728 {
729 cpumask_clear(*mask);
730 return true;
731 }
732
733 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
734 {
735 }
736
737 static inline void free_cpumask_var(cpumask_var_t mask)
738 {
739 }
740
741 static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
742 {
743 }
744
745 static inline bool cpumask_available(cpumask_var_t mask)
746 {
747 return true;
748 }
749 #endif /* CONFIG_CPUMASK_OFFSTACK */
750
751 /* It's common to want to use cpu_all_mask in struct member initializers,
752 * so it has to refer to an address rather than a pointer. */
753 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
754 #define cpu_all_mask to_cpumask(cpu_all_bits)
755
756 /* First bits of cpu_bit_bitmap are in fact unset. */
757 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
758
759 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
760 #define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask)
761 #define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask)
762
763 /* Wrappers for arch boot code to manipulate normally-constant masks */
764 void init_cpu_present(const struct cpumask *src);
765 void init_cpu_possible(const struct cpumask *src);
766 void init_cpu_online(const struct cpumask *src);
767
768 static inline void reset_cpu_possible_mask(void)
769 {
770 bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS);
771 }
772
773 static inline void
774 set_cpu_possible(unsigned int cpu, bool possible)
775 {
776 if (possible)
777 cpumask_set_cpu(cpu, &__cpu_possible_mask);
778 else
779 cpumask_clear_cpu(cpu, &__cpu_possible_mask);
780 }
781
782 static inline void
783 set_cpu_present(unsigned int cpu, bool present)
784 {
785 if (present)
786 cpumask_set_cpu(cpu, &__cpu_present_mask);
787 else
788 cpumask_clear_cpu(cpu, &__cpu_present_mask);
789 }
790
791 static inline void
792 set_cpu_online(unsigned int cpu, bool online)
793 {
794 if (online)
795 cpumask_set_cpu(cpu, &__cpu_online_mask);
796 else
797 cpumask_clear_cpu(cpu, &__cpu_online_mask);
798 }
799
800 static inline void
801 set_cpu_active(unsigned int cpu, bool active)
802 {
803 if (active)
804 cpumask_set_cpu(cpu, &__cpu_active_mask);
805 else
806 cpumask_clear_cpu(cpu, &__cpu_active_mask);
807 }
808
809
810 /**
811 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
812 * @bitmap: the bitmap
813 *
814 * There are a few places where cpumask_var_t isn't appropriate and
815 * static cpumasks must be used (eg. very early boot), yet we don't
816 * expose the definition of 'struct cpumask'.
817 *
818 * This does the conversion, and can be used as a constant initializer.
819 */
820 #define to_cpumask(bitmap) \
821 ((struct cpumask *)(1 ? (bitmap) \
822 : (void *)sizeof(__check_is_bitmap(bitmap))))
823
824 static inline int __check_is_bitmap(const unsigned long *bitmap)
825 {
826 return 1;
827 }
828
829 /*
830 * Special-case data structure for "single bit set only" constant CPU masks.
831 *
832 * We pre-generate all the 64 (or 32) possible bit positions, with enough
833 * padding to the left and the right, and return the constant pointer
834 * appropriately offset.
835 */
836 extern const unsigned long
837 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
838
839 static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
840 {
841 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
842 p -= cpu / BITS_PER_LONG;
843 return to_cpumask(p);
844 }
845
846 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))
847
848 #if NR_CPUS <= BITS_PER_LONG
849 #define CPU_BITS_ALL \
850 { \
851 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
852 }
853
854 #else /* NR_CPUS > BITS_PER_LONG */
855
856 #define CPU_BITS_ALL \
857 { \
858 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
859 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
860 }
861 #endif /* NR_CPUS > BITS_PER_LONG */
862
863 /**
864 * cpumap_print_to_pagebuf - copies the cpumask into the buffer either
865 * as comma-separated list of cpus or hex values of cpumask
866 * @list: indicates whether the cpumap must be list
867 * @mask: the cpumask to copy
868 * @buf: the buffer to copy into
869 *
870 * Returns the length of the (null-terminated) @buf string, zero if
871 * nothing is copied.
872 */
873 static inline ssize_t
874 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
875 {
876 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
877 nr_cpu_ids);
878 }
879
880 #if NR_CPUS <= BITS_PER_LONG
881 #define CPU_MASK_ALL \
882 (cpumask_t) { { \
883 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
884 } }
885 #else
886 #define CPU_MASK_ALL \
887 (cpumask_t) { { \
888 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
889 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
890 } }
891 #endif /* NR_CPUS > BITS_PER_LONG */
892
893 #define CPU_MASK_NONE \
894 (cpumask_t) { { \
895 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
896 } }
897
898 #define CPU_MASK_CPU0 \
899 (cpumask_t) { { \
900 [0] = 1UL \
901 } }
902
903 #endif /* __LINUX_CPUMASK_H */