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.
8 * See detailed comments in the file linux/bitmap.h describing the
9 * data type on which these cpumasks are based.
11 * For details of cpumask_scnprintf() and cpumask_parse(),
12 * see bitmap_scnprintf() and bitmap_parse() in lib/bitmap.c.
14 * The available cpumask operations are:
16 * void cpu_set(cpu, mask) turn on bit 'cpu' in mask
17 * void cpu_clear(cpu, mask) turn off bit 'cpu' in mask
18 * void cpus_setall(mask) set all bits
19 * void cpus_clear(mask) clear all bits
20 * int cpu_isset(cpu, mask) true iff bit 'cpu' set in mask
21 * int cpu_test_and_set(cpu, mask) test and set bit 'cpu' in mask
23 * void cpus_and(dst, src1, src2) dst = src1 & src2 [intersection]
24 * void cpus_or(dst, src1, src2) dst = src1 | src2 [union]
25 * void cpus_xor(dst, src1, src2) dst = src1 ^ src2
26 * void cpus_andnot(dst, src1, src2) dst = src1 & ~src2
27 * void cpus_complement(dst, src) dst = ~src
29 * int cpus_equal(mask1, mask2) Does mask1 == mask2?
30 * int cpus_intersects(mask1, mask2) Do mask1 and mask2 intersect?
31 * int cpus_subset(mask1, mask2) Is mask1 a subset of mask2?
32 * int cpus_empty(mask) Is mask empty (no bits sets)?
33 * int cpus_full(mask) Is mask full (all bits sets)?
34 * int cpus_weight(mask) Hamming weigh - number of set bits
36 * void cpus_shift_right(dst, src, n) Shift right
37 * void cpus_shift_left(dst, src, n) Shift left
39 * int first_cpu(mask) Number lowest set bit, or NR_CPUS
40 * int next_cpu(cpu, mask) Next cpu past 'cpu', or NR_CPUS
42 * cpumask_t cpumask_of_cpu(cpu) Return cpumask with bit 'cpu' set
43 * CPU_MASK_ALL Initializer - all bits set
44 * CPU_MASK_NONE Initializer - no bits set
45 * unsigned long *cpus_addr(mask) Array of unsigned long's in mask
47 * int cpumask_scnprintf(buf, len, mask) Format cpumask for printing
48 * int cpumask_parse(ubuf, ulen, mask) Parse ascii string as cpumask
50 * for_each_cpu_mask(cpu, mask) for-loop cpu over mask
52 * int num_online_cpus() Number of online CPUs
53 * int num_possible_cpus() Number of all possible CPUs
54 * int num_present_cpus() Number of present CPUs
56 * int cpu_online(cpu) Is some cpu online?
57 * int cpu_possible(cpu) Is some cpu possible?
58 * int cpu_present(cpu) Is some cpu present (can schedule)?
60 * int any_online_cpu(mask) First online cpu in mask
62 * for_each_cpu(cpu) for-loop cpu over cpu_possible_map
63 * for_each_online_cpu(cpu) for-loop cpu over cpu_online_map
64 * for_each_present_cpu(cpu) for-loop cpu over cpu_present_map
67 * 1) The 'type-checked' form of cpu_isset() causes gcc (3.3.2, anyway)
68 * to generate slightly worse code. Note for example the additional
69 * 40 lines of assembly code compiling the "for each possible cpu"
70 * loops buried in the disk_stat_read() macros calls when compiling
71 * drivers/block/genhd.c (arch i386, CONFIG_SMP=y). So use a simple
72 * one-line #define for cpu_isset(), instead of wrapping an inline
73 * inside a macro, the way we do the other calls.
76 #include <linux/threads.h>
77 #include <linux/bitmap.h>
80 typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
81 extern cpumask_t _unused_cpumask_arg_;
83 #define cpu_set(cpu, dst) __cpu_set((cpu), &(dst))
84 static inline void __cpu_set(int cpu, volatile cpumask_t *dstp)
86 set_bit(cpu, dstp->bits);
89 #define cpu_clear(cpu, dst) __cpu_clear((cpu), &(dst))
90 static inline void __cpu_clear(int cpu, volatile cpumask_t *dstp)
92 clear_bit(cpu, dstp->bits);
95 #define cpus_setall(dst) __cpus_setall(&(dst), NR_CPUS)
96 static inline void __cpus_setall(cpumask_t *dstp, int nbits)
98 bitmap_fill(dstp->bits, nbits);
101 #define cpus_clear(dst) __cpus_clear(&(dst), NR_CPUS)
102 static inline void __cpus_clear(cpumask_t *dstp, int nbits)
104 bitmap_zero(dstp->bits, nbits);
107 /* No static inline type checking - see Subtlety (1) above. */
108 #define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask).bits)
110 #define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), &(cpumask))
111 static inline int __cpu_test_and_set(int cpu, cpumask_t *addr)
113 return test_and_set_bit(cpu, addr->bits);
116 #define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS)
117 static inline void __cpus_and(cpumask_t *dstp, const cpumask_t *src1p,
118 const cpumask_t *src2p, int nbits)
120 bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
123 #define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS)
124 static inline void __cpus_or(cpumask_t *dstp, const cpumask_t *src1p,
125 const cpumask_t *src2p, int nbits)
127 bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits);
130 #define cpus_xor(dst, src1, src2) __cpus_xor(&(dst), &(src1), &(src2), NR_CPUS)
131 static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p,
132 const cpumask_t *src2p, int nbits)
134 bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits);
137 #define cpus_andnot(dst, src1, src2) \
138 __cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS)
139 static inline void __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p,
140 const cpumask_t *src2p, int nbits)
142 bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
145 #define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS)
146 static inline void __cpus_complement(cpumask_t *dstp,
147 const cpumask_t *srcp, int nbits)
149 bitmap_complement(dstp->bits, srcp->bits, nbits);
152 #define cpus_equal(src1, src2) __cpus_equal(&(src1), &(src2), NR_CPUS)
153 static inline int __cpus_equal(const cpumask_t *src1p,
154 const cpumask_t *src2p, int nbits)
156 return bitmap_equal(src1p->bits, src2p->bits, nbits);
159 #define cpus_intersects(src1, src2) __cpus_intersects(&(src1), &(src2), NR_CPUS)
160 static inline int __cpus_intersects(const cpumask_t *src1p,
161 const cpumask_t *src2p, int nbits)
163 return bitmap_intersects(src1p->bits, src2p->bits, nbits);
166 #define cpus_subset(src1, src2) __cpus_subset(&(src1), &(src2), NR_CPUS)
167 static inline int __cpus_subset(const cpumask_t *src1p,
168 const cpumask_t *src2p, int nbits)
170 return bitmap_subset(src1p->bits, src2p->bits, nbits);
173 #define cpus_empty(src) __cpus_empty(&(src), NR_CPUS)
174 static inline int __cpus_empty(const cpumask_t *srcp, int nbits)
176 return bitmap_empty(srcp->bits, nbits);
179 #define cpus_full(cpumask) __cpus_full(&(cpumask), NR_CPUS)
180 static inline int __cpus_full(const cpumask_t *srcp, int nbits)
182 return bitmap_full(srcp->bits, nbits);
185 #define cpus_weight(cpumask) __cpus_weight(&(cpumask), NR_CPUS)
186 static inline int __cpus_weight(const cpumask_t *srcp, int nbits)
188 return bitmap_weight(srcp->bits, nbits);
191 #define cpus_shift_right(dst, src, n) \
192 __cpus_shift_right(&(dst), &(src), (n), NR_CPUS)
193 static inline void __cpus_shift_right(cpumask_t *dstp,
194 const cpumask_t *srcp, int n, int nbits)
196 bitmap_shift_right(dstp->bits, srcp->bits, n, nbits);
199 #define cpus_shift_left(dst, src, n) \
200 __cpus_shift_left(&(dst), &(src), (n), NR_CPUS)
201 static inline void __cpus_shift_left(cpumask_t *dstp,
202 const cpumask_t *srcp, int n, int nbits)
204 bitmap_shift_left(dstp->bits, srcp->bits, n, nbits);
207 #define first_cpu(src) __first_cpu(&(src), NR_CPUS)
208 static inline int __first_cpu(const cpumask_t *srcp, int nbits)
210 return find_first_bit(srcp->bits, nbits);
213 #define next_cpu(n, src) __next_cpu((n), &(src), NR_CPUS)
214 static inline int __next_cpu(int n, const cpumask_t *srcp, int nbits)
216 return find_next_bit(srcp->bits, nbits, n+1);
219 #define cpumask_of_cpu(cpu) \
221 typeof(_unused_cpumask_arg_) m; \
222 if (sizeof(m) == sizeof(unsigned long)) { \
223 m.bits[0] = 1UL<<(cpu); \
231 #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS)
233 #if NR_CPUS <= BITS_PER_LONG
235 #define CPU_MASK_ALL \
237 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \
242 #define CPU_MASK_ALL \
244 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
245 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \
250 #define CPU_MASK_NONE \
252 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
255 #define CPU_MASK_CPU0 \
260 #define cpus_addr(src) ((src).bits)
262 #define cpumask_scnprintf(buf, len, src) \
263 __cpumask_scnprintf((buf), (len), &(src), NR_CPUS)
264 static inline int __cpumask_scnprintf(char *buf, int len,
265 const cpumask_t *srcp, int nbits)
267 return bitmap_scnprintf(buf, len, srcp->bits, nbits);
270 #define cpumask_parse(ubuf, ulen, src) \
271 __cpumask_parse((ubuf), (ulen), &(src), NR_CPUS)
272 static inline int __cpumask_parse(const char __user *buf, int len,
273 cpumask_t *dstp, int nbits)
275 return bitmap_parse(buf, len, dstp->bits, nbits);
279 #define for_each_cpu_mask(cpu, mask) \
280 for ((cpu) = first_cpu(mask); \
282 (cpu) = next_cpu((cpu), (mask)))
283 #else /* NR_CPUS == 1 */
284 #define for_each_cpu_mask(cpu, mask) for ((cpu) = 0; (cpu) < 1; (cpu)++)
288 * The following particular system cpumasks and operations manage
289 * possible, present and online cpus. Each of them is a fixed size
290 * bitmap of size NR_CPUS.
292 * #ifdef CONFIG_HOTPLUG_CPU
293 * cpu_possible_map - all NR_CPUS bits set
294 * cpu_present_map - has bit 'cpu' set iff cpu is populated
295 * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
297 * cpu_possible_map - has bit 'cpu' set iff cpu is populated
298 * cpu_present_map - copy of cpu_possible_map
299 * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
302 * In either case, NR_CPUS is fixed at compile time, as the static
303 * size of these bitmaps. The cpu_possible_map is fixed at boot
304 * time, as the set of CPU id's that it is possible might ever
305 * be plugged in at anytime during the life of that system boot.
306 * The cpu_present_map is dynamic(*), representing which CPUs
307 * are currently plugged in. And cpu_online_map is the dynamic
308 * subset of cpu_present_map, indicating those CPUs available
311 * If HOTPLUG is enabled, then cpu_possible_map is forced to have
312 * all NR_CPUS bits set, otherwise it is just the set of CPUs that
313 * ACPI reports present at boot.
315 * If HOTPLUG is enabled, then cpu_present_map varies dynamically,
316 * depending on what ACPI reports as currently plugged in, otherwise
317 * cpu_present_map is just a copy of cpu_possible_map.
319 * (*) Well, cpu_present_map is dynamic in the hotplug case. If not
320 * hotplug, it's a copy of cpu_possible_map, hence fixed at boot.
323 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
324 * assumption that their single CPU is online. The UP
325 * cpu_{online,possible,present}_maps are placebos. Changing them
326 * will have no useful affect on the following num_*_cpus()
327 * and cpu_*() macros in the UP case. This ugliness is a UP
328 * optimization - don't waste any instructions or memory references
329 * asking if you're online or how many CPUs there are if there is
331 * 2) Most SMP arch's #define some of these maps to be some
332 * other map specific to that arch. Therefore, the following
333 * must be #define macros, not inlines. To see why, examine
334 * the assembly code produced by the following. Note that
335 * set1() writes phys_x_map, but set2() writes x_map:
336 * int x_map, phys_x_map;
337 * #define set1(a) x_map = a
338 * inline void set2(int a) { x_map = a; }
339 * #define x_map phys_x_map
340 * main(){ set1(3); set2(5); }
343 extern cpumask_t cpu_possible_map;
344 extern cpumask_t cpu_online_map;
345 extern cpumask_t cpu_present_map;
348 #define num_online_cpus() cpus_weight(cpu_online_map)
349 #define num_possible_cpus() cpus_weight(cpu_possible_map)
350 #define num_present_cpus() cpus_weight(cpu_present_map)
351 #define cpu_online(cpu) cpu_isset((cpu), cpu_online_map)
352 #define cpu_possible(cpu) cpu_isset((cpu), cpu_possible_map)
353 #define cpu_present(cpu) cpu_isset((cpu), cpu_present_map)
355 #define num_online_cpus() 1
356 #define num_possible_cpus() 1
357 #define num_present_cpus() 1
358 #define cpu_online(cpu) ((cpu) == 0)
359 #define cpu_possible(cpu) ((cpu) == 0)
360 #define cpu_present(cpu) ((cpu) == 0)
363 #define any_online_cpu(mask) \
366 for_each_cpu_mask(cpu, (mask)) \
367 if (cpu_online(cpu)) \
372 #define for_each_cpu(cpu) for_each_cpu_mask((cpu), cpu_possible_map)
373 #define for_each_online_cpu(cpu) for_each_cpu_mask((cpu), cpu_online_map)
374 #define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map)
376 #endif /* __LINUX_CPUMASK_H */