1 #ifndef __LINUX_CPUMASK_H
2 #define __LINUX_CPUMASK_H
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.
9 #include <linux/kernel.h>
10 #include <linux/threads.h>
11 #include <linux/bitmap.h>
12 #include <linux/bug.h>
14 /* Don't assign or return these: may not be this big! */
15 typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
18 * cpumask_bits - get the bits in a cpumask
19 * @maskp: the struct cpumask *
21 * You should only assume nr_cpu_ids bits of this mask are valid. This is
22 * a macro so it's const-correct.
24 #define cpumask_bits(maskp) ((maskp)->bits)
27 * cpumask_pr_args - printf args to output a cpumask
28 * @maskp: cpumask to be printed
30 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask.
32 #define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp)
37 extern int nr_cpu_ids;
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 nr_cpu_ids
45 #define nr_cpumask_bits NR_CPUS
49 * The following particular system cpumasks and operations manage
50 * possible, present, active and online cpus.
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
57 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
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.
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.
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.
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.
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
88 extern const struct cpumask *const cpu_possible_mask;
89 extern const struct cpumask *const cpu_online_mask;
90 extern const struct cpumask *const cpu_present_mask;
91 extern const struct cpumask *const cpu_active_mask;
94 #define num_online_cpus() cpumask_weight(cpu_online_mask)
95 #define num_possible_cpus() cpumask_weight(cpu_possible_mask)
96 #define num_present_cpus() cpumask_weight(cpu_present_mask)
97 #define num_active_cpus() cpumask_weight(cpu_active_mask)
98 #define cpu_online(cpu) cpumask_test_cpu((cpu), cpu_online_mask)
99 #define cpu_possible(cpu) cpumask_test_cpu((cpu), cpu_possible_mask)
100 #define cpu_present(cpu) cpumask_test_cpu((cpu), cpu_present_mask)
101 #define cpu_active(cpu) cpumask_test_cpu((cpu), cpu_active_mask)
103 #define num_online_cpus() 1U
104 #define num_possible_cpus() 1U
105 #define num_present_cpus() 1U
106 #define num_active_cpus() 1U
107 #define cpu_online(cpu) ((cpu) == 0)
108 #define cpu_possible(cpu) ((cpu) == 0)
109 #define cpu_present(cpu) ((cpu) == 0)
110 #define cpu_active(cpu) ((cpu) == 0)
113 /* verify cpu argument to cpumask_* operators */
114 static inline unsigned int cpumask_check(unsigned int cpu)
116 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
117 WARN_ON_ONCE(cpu >= nr_cpumask_bits);
118 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
123 /* Uniprocessor. Assume all masks are "1". */
124 static inline unsigned int cpumask_first(const struct cpumask *srcp)
129 /* Valid inputs for n are -1 and 0. */
130 static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
135 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
140 static inline unsigned int cpumask_next_and(int n,
141 const struct cpumask *srcp,
142 const struct cpumask *andp)
147 /* cpu must be a valid cpu, ie 0, so there's no other choice. */
148 static inline unsigned int cpumask_any_but(const struct cpumask *mask,
154 static inline int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp)
156 set_bit(0, cpumask_bits(dstp));
161 #define for_each_cpu(cpu, mask) \
162 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
163 #define for_each_cpu_not(cpu, mask) \
164 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
165 #define for_each_cpu_and(cpu, mask, and) \
166 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)and)
169 * cpumask_first - get the first cpu in a cpumask
170 * @srcp: the cpumask pointer
172 * Returns >= nr_cpu_ids if no cpus set.
174 static inline unsigned int cpumask_first(const struct cpumask *srcp)
176 return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
180 * cpumask_next - get the next cpu in a cpumask
181 * @n: the cpu prior to the place to search (ie. return will be > @n)
182 * @srcp: the cpumask pointer
184 * Returns >= nr_cpu_ids if no further cpus set.
186 static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
188 /* -1 is a legal arg here. */
191 return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
195 * cpumask_next_zero - get the next unset cpu in a cpumask
196 * @n: the cpu prior to the place to search (ie. return will be > @n)
197 * @srcp: the cpumask pointer
199 * Returns >= nr_cpu_ids if no further cpus unset.
201 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
203 /* -1 is a legal arg here. */
206 return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
209 int cpumask_next_and(int n, const struct cpumask *, const struct cpumask *);
210 int cpumask_any_but(const struct cpumask *mask, unsigned int cpu);
211 int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp);
214 * for_each_cpu - iterate over every cpu in a mask
215 * @cpu: the (optionally unsigned) integer iterator
216 * @mask: the cpumask pointer
218 * After the loop, cpu is >= nr_cpu_ids.
220 #define for_each_cpu(cpu, mask) \
222 (cpu) = cpumask_next((cpu), (mask)), \
226 * for_each_cpu_not - iterate over every cpu in a complemented mask
227 * @cpu: the (optionally unsigned) integer iterator
228 * @mask: the cpumask pointer
230 * After the loop, cpu is >= nr_cpu_ids.
232 #define for_each_cpu_not(cpu, mask) \
234 (cpu) = cpumask_next_zero((cpu), (mask)), \
238 * for_each_cpu_and - iterate over every cpu in both masks
239 * @cpu: the (optionally unsigned) integer iterator
240 * @mask: the first cpumask pointer
241 * @and: the second cpumask pointer
243 * This saves a temporary CPU mask in many places. It is equivalent to:
244 * struct cpumask tmp;
245 * cpumask_and(&tmp, &mask, &and);
246 * for_each_cpu(cpu, &tmp)
249 * After the loop, cpu is >= nr_cpu_ids.
251 #define for_each_cpu_and(cpu, mask, and) \
253 (cpu) = cpumask_next_and((cpu), (mask), (and)), \
257 #define CPU_BITS_NONE \
259 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
262 #define CPU_BITS_CPU0 \
268 * cpumask_set_cpu - set a cpu in a cpumask
269 * @cpu: cpu number (< nr_cpu_ids)
270 * @dstp: the cpumask pointer
272 static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
274 set_bit(cpumask_check(cpu), cpumask_bits(dstp));
278 * cpumask_clear_cpu - clear a cpu in a cpumask
279 * @cpu: cpu number (< nr_cpu_ids)
280 * @dstp: the cpumask pointer
282 static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
284 clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
288 * cpumask_test_cpu - test for a cpu in a cpumask
289 * @cpu: cpu number (< nr_cpu_ids)
290 * @cpumask: the cpumask pointer
292 * Returns 1 if @cpu is set in @cpumask, else returns 0
294 static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask)
296 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask)));
300 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
301 * @cpu: cpu number (< nr_cpu_ids)
302 * @cpumask: the cpumask pointer
304 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
306 * test_and_set_bit wrapper for cpumasks.
308 static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
310 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
314 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
315 * @cpu: cpu number (< nr_cpu_ids)
316 * @cpumask: the cpumask pointer
318 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
320 * test_and_clear_bit wrapper for cpumasks.
322 static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
324 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
328 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
329 * @dstp: the cpumask pointer
331 static inline void cpumask_setall(struct cpumask *dstp)
333 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
337 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
338 * @dstp: the cpumask pointer
340 static inline void cpumask_clear(struct cpumask *dstp)
342 bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits);
346 * cpumask_and - *dstp = *src1p & *src2p
347 * @dstp: the cpumask result
348 * @src1p: the first input
349 * @src2p: the second input
351 * If *@dstp is empty, returns 0, else returns 1
353 static inline int cpumask_and(struct cpumask *dstp,
354 const struct cpumask *src1p,
355 const struct cpumask *src2p)
357 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
358 cpumask_bits(src2p), nr_cpumask_bits);
362 * cpumask_or - *dstp = *src1p | *src2p
363 * @dstp: the cpumask result
364 * @src1p: the first input
365 * @src2p: the second input
367 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
368 const struct cpumask *src2p)
370 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
371 cpumask_bits(src2p), nr_cpumask_bits);
375 * cpumask_xor - *dstp = *src1p ^ *src2p
376 * @dstp: the cpumask result
377 * @src1p: the first input
378 * @src2p: the second input
380 static inline void cpumask_xor(struct cpumask *dstp,
381 const struct cpumask *src1p,
382 const struct cpumask *src2p)
384 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
385 cpumask_bits(src2p), nr_cpumask_bits);
389 * cpumask_andnot - *dstp = *src1p & ~*src2p
390 * @dstp: the cpumask result
391 * @src1p: the first input
392 * @src2p: the second input
394 * If *@dstp is empty, returns 0, else returns 1
396 static inline int cpumask_andnot(struct cpumask *dstp,
397 const struct cpumask *src1p,
398 const struct cpumask *src2p)
400 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
401 cpumask_bits(src2p), nr_cpumask_bits);
405 * cpumask_complement - *dstp = ~*srcp
406 * @dstp: the cpumask result
407 * @srcp: the input to invert
409 static inline void cpumask_complement(struct cpumask *dstp,
410 const struct cpumask *srcp)
412 bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp),
417 * cpumask_equal - *src1p == *src2p
418 * @src1p: the first input
419 * @src2p: the second input
421 static inline bool cpumask_equal(const struct cpumask *src1p,
422 const struct cpumask *src2p)
424 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
429 * cpumask_intersects - (*src1p & *src2p) != 0
430 * @src1p: the first input
431 * @src2p: the second input
433 static inline bool cpumask_intersects(const struct cpumask *src1p,
434 const struct cpumask *src2p)
436 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
441 * cpumask_subset - (*src1p & ~*src2p) == 0
442 * @src1p: the first input
443 * @src2p: the second input
445 * Returns 1 if *@src1p is a subset of *@src2p, else returns 0
447 static inline int cpumask_subset(const struct cpumask *src1p,
448 const struct cpumask *src2p)
450 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
455 * cpumask_empty - *srcp == 0
456 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
458 static inline bool cpumask_empty(const struct cpumask *srcp)
460 return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits);
464 * cpumask_full - *srcp == 0xFFFFFFFF...
465 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
467 static inline bool cpumask_full(const struct cpumask *srcp)
469 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
473 * cpumask_weight - Count of bits in *srcp
474 * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
476 static inline unsigned int cpumask_weight(const struct cpumask *srcp)
478 return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits);
482 * cpumask_shift_right - *dstp = *srcp >> n
483 * @dstp: the cpumask result
484 * @srcp: the input to shift
485 * @n: the number of bits to shift by
487 static inline void cpumask_shift_right(struct cpumask *dstp,
488 const struct cpumask *srcp, int n)
490 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
495 * cpumask_shift_left - *dstp = *srcp << n
496 * @dstp: the cpumask result
497 * @srcp: the input to shift
498 * @n: the number of bits to shift by
500 static inline void cpumask_shift_left(struct cpumask *dstp,
501 const struct cpumask *srcp, int n)
503 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
508 * cpumask_copy - *dstp = *srcp
510 * @srcp: the input cpumask
512 static inline void cpumask_copy(struct cpumask *dstp,
513 const struct cpumask *srcp)
515 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits);
519 * cpumask_any - pick a "random" cpu from *srcp
520 * @srcp: the input cpumask
522 * Returns >= nr_cpu_ids if no cpus set.
524 #define cpumask_any(srcp) cpumask_first(srcp)
527 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
528 * @src1p: the first input
529 * @src2p: the second input
531 * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and().
533 #define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p))
536 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
537 * @mask1: the first input cpumask
538 * @mask2: the second input cpumask
540 * Returns >= nr_cpu_ids if no cpus set.
542 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
545 * cpumask_of - the cpumask containing just a given cpu
546 * @cpu: the cpu (<= nr_cpu_ids)
548 #define cpumask_of(cpu) (get_cpu_mask(cpu))
551 * cpumask_parse_user - extract a cpumask from a user string
552 * @buf: the buffer to extract from
553 * @len: the length of the buffer
554 * @dstp: the cpumask to set.
556 * Returns -errno, or 0 for success.
558 static inline int cpumask_parse_user(const char __user *buf, int len,
559 struct cpumask *dstp)
561 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpu_ids);
565 * cpumask_parselist_user - extract a cpumask from a user string
566 * @buf: the buffer to extract from
567 * @len: the length of the buffer
568 * @dstp: the cpumask to set.
570 * Returns -errno, or 0 for success.
572 static inline int cpumask_parselist_user(const char __user *buf, int len,
573 struct cpumask *dstp)
575 return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
580 * cpumask_parse - extract a cpumask from from a string
581 * @buf: the buffer to extract from
582 * @dstp: the cpumask to set.
584 * Returns -errno, or 0 for success.
586 static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
588 char *nl = strchr(buf, '\n');
589 unsigned int len = nl ? (unsigned int)(nl - buf) : strlen(buf);
591 return bitmap_parse(buf, len, cpumask_bits(dstp), nr_cpu_ids);
595 * cpulist_parse - extract a cpumask from a user string of ranges
596 * @buf: the buffer to extract from
597 * @dstp: the cpumask to set.
599 * Returns -errno, or 0 for success.
601 static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
603 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpu_ids);
607 * cpumask_size - size to allocate for a 'struct cpumask' in bytes
609 * This will eventually be a runtime variable, depending on nr_cpu_ids.
611 static inline size_t cpumask_size(void)
613 return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
617 * cpumask_var_t: struct cpumask for stack usage.
619 * Oh, the wicked games we play! In order to make kernel coding a
620 * little more difficult, we typedef cpumask_var_t to an array or a
621 * pointer: doing &mask on an array is a noop, so it still works.
624 * cpumask_var_t tmpmask;
625 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
628 * ... use 'tmpmask' like a normal struct cpumask * ...
630 * free_cpumask_var(tmpmask);
633 * However, one notable exception is there. alloc_cpumask_var() allocates
634 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has
635 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t.
637 * cpumask_var_t tmpmask;
638 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
643 * This code makes NR_CPUS length memcopy and brings to a memory corruption.
644 * cpumask_copy() provide safe copy functionality.
646 * Note that there is another evil here: If you define a cpumask_var_t
647 * as a percpu variable then the way to obtain the address of the cpumask
648 * structure differently influences what this_cpu_* operation needs to be
649 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use
650 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the
651 * other type of cpumask_var_t implementation is configured.
653 #ifdef CONFIG_CPUMASK_OFFSTACK
654 typedef struct cpumask *cpumask_var_t;
656 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
658 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
659 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
660 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
661 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
662 void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
663 void free_cpumask_var(cpumask_var_t mask);
664 void free_bootmem_cpumask_var(cpumask_var_t mask);
667 typedef struct cpumask cpumask_var_t[1];
669 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
671 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
676 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
682 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
684 cpumask_clear(*mask);
688 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
691 cpumask_clear(*mask);
695 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
699 static inline void free_cpumask_var(cpumask_var_t mask)
703 static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
706 #endif /* CONFIG_CPUMASK_OFFSTACK */
708 /* It's common to want to use cpu_all_mask in struct member initializers,
709 * so it has to refer to an address rather than a pointer. */
710 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
711 #define cpu_all_mask to_cpumask(cpu_all_bits)
713 /* First bits of cpu_bit_bitmap are in fact unset. */
714 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
716 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
717 #define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask)
718 #define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask)
720 /* Wrappers for arch boot code to manipulate normally-constant masks */
721 void set_cpu_possible(unsigned int cpu, bool possible);
722 void set_cpu_present(unsigned int cpu, bool present);
723 void set_cpu_online(unsigned int cpu, bool online);
724 void set_cpu_active(unsigned int cpu, bool active);
725 void init_cpu_present(const struct cpumask *src);
726 void init_cpu_possible(const struct cpumask *src);
727 void init_cpu_online(const struct cpumask *src);
730 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
731 * @bitmap: the bitmap
733 * There are a few places where cpumask_var_t isn't appropriate and
734 * static cpumasks must be used (eg. very early boot), yet we don't
735 * expose the definition of 'struct cpumask'.
737 * This does the conversion, and can be used as a constant initializer.
739 #define to_cpumask(bitmap) \
740 ((struct cpumask *)(1 ? (bitmap) \
741 : (void *)sizeof(__check_is_bitmap(bitmap))))
743 static inline int __check_is_bitmap(const unsigned long *bitmap)
749 * Special-case data structure for "single bit set only" constant CPU masks.
751 * We pre-generate all the 64 (or 32) possible bit positions, with enough
752 * padding to the left and the right, and return the constant pointer
753 * appropriately offset.
755 extern const unsigned long
756 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
758 static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
760 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
761 p -= cpu / BITS_PER_LONG;
762 return to_cpumask(p);
765 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))
767 #if NR_CPUS <= BITS_PER_LONG
768 #define CPU_BITS_ALL \
770 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
773 #else /* NR_CPUS > BITS_PER_LONG */
775 #define CPU_BITS_ALL \
777 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
778 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
780 #endif /* NR_CPUS > BITS_PER_LONG */
783 * cpumap_print_to_pagebuf - copies the cpumask into the buffer either
784 * as comma-separated list of cpus or hex values of cpumask
785 * @list: indicates whether the cpumap must be list
786 * @mask: the cpumask to copy
787 * @buf: the buffer to copy into
789 * Returns the length of the (null-terminated) @buf string, zero if
792 static inline ssize_t
793 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask)
795 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask),
799 #if NR_CPUS <= BITS_PER_LONG
800 #define CPU_MASK_ALL \
802 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
805 #define CPU_MASK_ALL \
807 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
808 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \
810 #endif /* NR_CPUS > BITS_PER_LONG */
812 #define CPU_MASK_NONE \
814 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
817 #define CPU_MASK_CPU0 \
822 #endif /* __LINUX_CPUMASK_H */