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.
7 *
8 * See detailed comments in the file linux/bitmap.h describing the
9 * data type on which these cpumasks are based.
10 *
11 * For details of cpumask_scnprintf() and cpumask_parse(),
12 * see bitmap_scnprintf() and bitmap_parse() in lib/bitmap.c.
13 * For details of cpulist_scnprintf() and cpulist_parse(), see
14 * bitmap_scnlistprintf() and bitmap_parselist(), also in bitmap.c.
15 * For details of cpu_remap(), see bitmap_bitremap in lib/bitmap.c
16 * For details of cpus_remap(), see bitmap_remap in lib/bitmap.c.
17 *
18 * The available cpumask operations are:
19 *
20 * void cpu_set(cpu, mask) turn on bit 'cpu' in mask
21 * void cpu_clear(cpu, mask) turn off bit 'cpu' in mask
22 * void cpus_setall(mask) set all bits
23 * void cpus_clear(mask) clear all bits
24 * int cpu_isset(cpu, mask) true iff bit 'cpu' set in mask
25 * int cpu_test_and_set(cpu, mask) test and set bit 'cpu' in mask
26 *
27 * void cpus_and(dst, src1, src2) dst = src1 & src2 [intersection]
28 * void cpus_or(dst, src1, src2) dst = src1 | src2 [union]
29 * void cpus_xor(dst, src1, src2) dst = src1 ^ src2
30 * void cpus_andnot(dst, src1, src2) dst = src1 & ~src2
31 * void cpus_complement(dst, src) dst = ~src
32 *
33 * int cpus_equal(mask1, mask2) Does mask1 == mask2?
34 * int cpus_intersects(mask1, mask2) Do mask1 and mask2 intersect?
35 * int cpus_subset(mask1, mask2) Is mask1 a subset of mask2?
36 * int cpus_empty(mask) Is mask empty (no bits sets)?
37 * int cpus_full(mask) Is mask full (all bits sets)?
38 * int cpus_weight(mask) Hamming weigh - number of set bits
39 *
40 * void cpus_shift_right(dst, src, n) Shift right
41 * void cpus_shift_left(dst, src, n) Shift left
42 *
43 * int first_cpu(mask) Number lowest set bit, or NR_CPUS
44 * int next_cpu(cpu, mask) Next cpu past 'cpu', or NR_CPUS
45 *
46 * cpumask_t cpumask_of_cpu(cpu) Return cpumask with bit 'cpu' set
47 * CPU_MASK_ALL Initializer - all bits set
48 * CPU_MASK_NONE Initializer - no bits set
49 * unsigned long *cpus_addr(mask) Array of unsigned long's in mask
50 *
51 * int cpumask_scnprintf(buf, len, mask) Format cpumask for printing
52 * int cpumask_parse(ubuf, ulen, mask) Parse ascii string as cpumask
53 * int cpulist_scnprintf(buf, len, mask) Format cpumask as list for printing
54 * int cpulist_parse(buf, map) Parse ascii string as cpulist
55 * int cpu_remap(oldbit, old, new) newbit = map(old, new)(oldbit)
56 * int cpus_remap(dst, src, old, new) *dst = map(old, new)(src)
57 *
58 * for_each_cpu_mask(cpu, mask) for-loop cpu over mask
59 *
60 * int num_online_cpus() Number of online CPUs
61 * int num_possible_cpus() Number of all possible CPUs
62 * int num_present_cpus() Number of present CPUs
63 *
64 * int cpu_online(cpu) Is some cpu online?
65 * int cpu_possible(cpu) Is some cpu possible?
66 * int cpu_present(cpu) Is some cpu present (can schedule)?
67 *
68 * int any_online_cpu(mask) First online cpu in mask
69 *
70 * for_each_possible_cpu(cpu) for-loop cpu over cpu_possible_map
71 * for_each_online_cpu(cpu) for-loop cpu over cpu_online_map
72 * for_each_present_cpu(cpu) for-loop cpu over cpu_present_map
73 *
74 * Subtlety:
75 * 1) The 'type-checked' form of cpu_isset() causes gcc (3.3.2, anyway)
76 * to generate slightly worse code. Note for example the additional
77 * 40 lines of assembly code compiling the "for each possible cpu"
78 * loops buried in the disk_stat_read() macros calls when compiling
79 * drivers/block/genhd.c (arch i386, CONFIG_SMP=y). So use a simple
80 * one-line #define for cpu_isset(), instead of wrapping an inline
81 * inside a macro, the way we do the other calls.
82 */
83
84 #include <linux/kernel.h>
85 #include <linux/threads.h>
86 #include <linux/bitmap.h>
87
88 typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
89 extern cpumask_t _unused_cpumask_arg_;
90
91 #define cpu_set(cpu, dst) __cpu_set((cpu), &(dst))
__cpu_set(int cpu,volatile cpumask_t * dstp)92 static inline void __cpu_set(int cpu, volatile cpumask_t *dstp)
93 {
94 set_bit(cpu, dstp->bits);
95 }
96
97 #define cpu_clear(cpu, dst) __cpu_clear((cpu), &(dst))
__cpu_clear(int cpu,volatile cpumask_t * dstp)98 static inline void __cpu_clear(int cpu, volatile cpumask_t *dstp)
99 {
100 clear_bit(cpu, dstp->bits);
101 }
102
103 #define cpus_setall(dst) __cpus_setall(&(dst), NR_CPUS)
__cpus_setall(cpumask_t * dstp,int nbits)104 static inline void __cpus_setall(cpumask_t *dstp, int nbits)
105 {
106 bitmap_fill(dstp->bits, nbits);
107 }
108
109 #define cpus_clear(dst) __cpus_clear(&(dst), NR_CPUS)
__cpus_clear(cpumask_t * dstp,int nbits)110 static inline void __cpus_clear(cpumask_t *dstp, int nbits)
111 {
112 bitmap_zero(dstp->bits, nbits);
113 }
114
115 /* No static inline type checking - see Subtlety (1) above. */
116 #define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask).bits)
117
118 #define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), &(cpumask))
__cpu_test_and_set(int cpu,cpumask_t * addr)119 static inline int __cpu_test_and_set(int cpu, cpumask_t *addr)
120 {
121 return test_and_set_bit(cpu, addr->bits);
122 }
123
124 #define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS)
__cpus_and(cpumask_t * dstp,const cpumask_t * src1p,const cpumask_t * src2p,int nbits)125 static inline void __cpus_and(cpumask_t *dstp, const cpumask_t *src1p,
126 const cpumask_t *src2p, int nbits)
127 {
128 bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
129 }
130
131 #define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS)
__cpus_or(cpumask_t * dstp,const cpumask_t * src1p,const cpumask_t * src2p,int nbits)132 static inline void __cpus_or(cpumask_t *dstp, const cpumask_t *src1p,
133 const cpumask_t *src2p, int nbits)
134 {
135 bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits);
136 }
137
138 #define cpus_xor(dst, src1, src2) __cpus_xor(&(dst), &(src1), &(src2), NR_CPUS)
__cpus_xor(cpumask_t * dstp,const cpumask_t * src1p,const cpumask_t * src2p,int nbits)139 static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p,
140 const cpumask_t *src2p, int nbits)
141 {
142 bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits);
143 }
144
145 #define cpus_andnot(dst, src1, src2) \
146 __cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS)
__cpus_andnot(cpumask_t * dstp,const cpumask_t * src1p,const cpumask_t * src2p,int nbits)147 static inline void __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p,
148 const cpumask_t *src2p, int nbits)
149 {
150 bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
151 }
152
153 #define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS)
__cpus_complement(cpumask_t * dstp,const cpumask_t * srcp,int nbits)154 static inline void __cpus_complement(cpumask_t *dstp,
155 const cpumask_t *srcp, int nbits)
156 {
157 bitmap_complement(dstp->bits, srcp->bits, nbits);
158 }
159
160 #define cpus_equal(src1, src2) __cpus_equal(&(src1), &(src2), NR_CPUS)
__cpus_equal(const cpumask_t * src1p,const cpumask_t * src2p,int nbits)161 static inline int __cpus_equal(const cpumask_t *src1p,
162 const cpumask_t *src2p, int nbits)
163 {
164 return bitmap_equal(src1p->bits, src2p->bits, nbits);
165 }
166
167 #define cpus_intersects(src1, src2) __cpus_intersects(&(src1), &(src2), NR_CPUS)
__cpus_intersects(const cpumask_t * src1p,const cpumask_t * src2p,int nbits)168 static inline int __cpus_intersects(const cpumask_t *src1p,
169 const cpumask_t *src2p, int nbits)
170 {
171 return bitmap_intersects(src1p->bits, src2p->bits, nbits);
172 }
173
174 #define cpus_subset(src1, src2) __cpus_subset(&(src1), &(src2), NR_CPUS)
__cpus_subset(const cpumask_t * src1p,const cpumask_t * src2p,int nbits)175 static inline int __cpus_subset(const cpumask_t *src1p,
176 const cpumask_t *src2p, int nbits)
177 {
178 return bitmap_subset(src1p->bits, src2p->bits, nbits);
179 }
180
181 #define cpus_empty(src) __cpus_empty(&(src), NR_CPUS)
__cpus_empty(const cpumask_t * srcp,int nbits)182 static inline int __cpus_empty(const cpumask_t *srcp, int nbits)
183 {
184 return bitmap_empty(srcp->bits, nbits);
185 }
186
187 #define cpus_full(cpumask) __cpus_full(&(cpumask), NR_CPUS)
__cpus_full(const cpumask_t * srcp,int nbits)188 static inline int __cpus_full(const cpumask_t *srcp, int nbits)
189 {
190 return bitmap_full(srcp->bits, nbits);
191 }
192
193 #define cpus_weight(cpumask) __cpus_weight(&(cpumask), NR_CPUS)
__cpus_weight(const cpumask_t * srcp,int nbits)194 static inline int __cpus_weight(const cpumask_t *srcp, int nbits)
195 {
196 return bitmap_weight(srcp->bits, nbits);
197 }
198
199 #define cpus_shift_right(dst, src, n) \
200 __cpus_shift_right(&(dst), &(src), (n), NR_CPUS)
__cpus_shift_right(cpumask_t * dstp,const cpumask_t * srcp,int n,int nbits)201 static inline void __cpus_shift_right(cpumask_t *dstp,
202 const cpumask_t *srcp, int n, int nbits)
203 {
204 bitmap_shift_right(dstp->bits, srcp->bits, n, nbits);
205 }
206
207 #define cpus_shift_left(dst, src, n) \
208 __cpus_shift_left(&(dst), &(src), (n), NR_CPUS)
__cpus_shift_left(cpumask_t * dstp,const cpumask_t * srcp,int n,int nbits)209 static inline void __cpus_shift_left(cpumask_t *dstp,
210 const cpumask_t *srcp, int n, int nbits)
211 {
212 bitmap_shift_left(dstp->bits, srcp->bits, n, nbits);
213 }
214
215 #ifdef CONFIG_SMP
216 int __first_cpu(const cpumask_t *srcp);
217 #define first_cpu(src) __first_cpu(&(src))
218 int __next_cpu(int n, const cpumask_t *srcp);
219 #define next_cpu(n, src) __next_cpu((n), &(src))
220 #else
221 #define first_cpu(src) 0
222 #define next_cpu(n, src) 1
223 #endif
224
225 #define cpumask_of_cpu(cpu) \
226 ({ \
227 typeof(_unused_cpumask_arg_) m; \
228 if (sizeof(m) == sizeof(unsigned long)) { \
229 m.bits[0] = 1UL<<(cpu); \
230 } else { \
231 cpus_clear(m); \
232 cpu_set((cpu), m); \
233 } \
234 m; \
235 })
236
237 #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS)
238
239 #if NR_CPUS <= BITS_PER_LONG
240
241 #define CPU_MASK_ALL \
242 (cpumask_t) { { \
243 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \
244 } }
245
246 #else
247
248 #define CPU_MASK_ALL \
249 (cpumask_t) { { \
250 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \
251 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \
252 } }
253
254 #endif
255
256 #define CPU_MASK_NONE \
257 (cpumask_t) { { \
258 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
259 } }
260
261 #define CPU_MASK_CPU0 \
262 (cpumask_t) { { \
263 [0] = 1UL \
264 } }
265
266 #define cpus_addr(src) ((src).bits)
267
268 #define cpumask_scnprintf(buf, len, src) \
269 __cpumask_scnprintf((buf), (len), &(src), NR_CPUS)
__cpumask_scnprintf(char * buf,int len,const cpumask_t * srcp,int nbits)270 static inline int __cpumask_scnprintf(char *buf, int len,
271 const cpumask_t *srcp, int nbits)
272 {
273 return bitmap_scnprintf(buf, len, srcp->bits, nbits);
274 }
275
276 #define cpumask_parse(ubuf, ulen, dst) \
277 __cpumask_parse((ubuf), (ulen), &(dst), NR_CPUS)
__cpumask_parse(const char __user * buf,int len,cpumask_t * dstp,int nbits)278 static inline int __cpumask_parse(const char __user *buf, int len,
279 cpumask_t *dstp, int nbits)
280 {
281 return bitmap_parse(buf, len, dstp->bits, nbits);
282 }
283
284 #define cpulist_scnprintf(buf, len, src) \
285 __cpulist_scnprintf((buf), (len), &(src), NR_CPUS)
__cpulist_scnprintf(char * buf,int len,const cpumask_t * srcp,int nbits)286 static inline int __cpulist_scnprintf(char *buf, int len,
287 const cpumask_t *srcp, int nbits)
288 {
289 return bitmap_scnlistprintf(buf, len, srcp->bits, nbits);
290 }
291
292 #define cpulist_parse(buf, dst) __cpulist_parse((buf), &(dst), NR_CPUS)
__cpulist_parse(const char * buf,cpumask_t * dstp,int nbits)293 static inline int __cpulist_parse(const char *buf, cpumask_t *dstp, int nbits)
294 {
295 return bitmap_parselist(buf, dstp->bits, nbits);
296 }
297
298 #define cpu_remap(oldbit, old, new) \
299 __cpu_remap((oldbit), &(old), &(new), NR_CPUS)
__cpu_remap(int oldbit,const cpumask_t * oldp,const cpumask_t * newp,int nbits)300 static inline int __cpu_remap(int oldbit,
301 const cpumask_t *oldp, const cpumask_t *newp, int nbits)
302 {
303 return bitmap_bitremap(oldbit, oldp->bits, newp->bits, nbits);
304 }
305
306 #define cpus_remap(dst, src, old, new) \
307 __cpus_remap(&(dst), &(src), &(old), &(new), NR_CPUS)
__cpus_remap(cpumask_t * dstp,const cpumask_t * srcp,const cpumask_t * oldp,const cpumask_t * newp,int nbits)308 static inline void __cpus_remap(cpumask_t *dstp, const cpumask_t *srcp,
309 const cpumask_t *oldp, const cpumask_t *newp, int nbits)
310 {
311 bitmap_remap(dstp->bits, srcp->bits, oldp->bits, newp->bits, nbits);
312 }
313
314 #if NR_CPUS > 1
315 #define for_each_cpu_mask(cpu, mask) \
316 for ((cpu) = first_cpu(mask); \
317 (cpu) < NR_CPUS; \
318 (cpu) = next_cpu((cpu), (mask)))
319 #else /* NR_CPUS == 1 */
320 #define for_each_cpu_mask(cpu, mask) \
321 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
322 #endif /* NR_CPUS */
323
324 /*
325 * The following particular system cpumasks and operations manage
326 * possible, present and online cpus. Each of them is a fixed size
327 * bitmap of size NR_CPUS.
328 *
329 * #ifdef CONFIG_HOTPLUG_CPU
330 * cpu_possible_map - has bit 'cpu' set iff cpu is populatable
331 * cpu_present_map - has bit 'cpu' set iff cpu is populated
332 * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
333 * #else
334 * cpu_possible_map - has bit 'cpu' set iff cpu is populated
335 * cpu_present_map - copy of cpu_possible_map
336 * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
337 * #endif
338 *
339 * In either case, NR_CPUS is fixed at compile time, as the static
340 * size of these bitmaps. The cpu_possible_map is fixed at boot
341 * time, as the set of CPU id's that it is possible might ever
342 * be plugged in at anytime during the life of that system boot.
343 * The cpu_present_map is dynamic(*), representing which CPUs
344 * are currently plugged in. And cpu_online_map is the dynamic
345 * subset of cpu_present_map, indicating those CPUs available
346 * for scheduling.
347 *
348 * If HOTPLUG is enabled, then cpu_possible_map is forced to have
349 * all NR_CPUS bits set, otherwise it is just the set of CPUs that
350 * ACPI reports present at boot.
351 *
352 * If HOTPLUG is enabled, then cpu_present_map varies dynamically,
353 * depending on what ACPI reports as currently plugged in, otherwise
354 * cpu_present_map is just a copy of cpu_possible_map.
355 *
356 * (*) Well, cpu_present_map is dynamic in the hotplug case. If not
357 * hotplug, it's a copy of cpu_possible_map, hence fixed at boot.
358 *
359 * Subtleties:
360 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
361 * assumption that their single CPU is online. The UP
362 * cpu_{online,possible,present}_maps are placebos. Changing them
363 * will have no useful affect on the following num_*_cpus()
364 * and cpu_*() macros in the UP case. This ugliness is a UP
365 * optimization - don't waste any instructions or memory references
366 * asking if you're online or how many CPUs there are if there is
367 * only one CPU.
368 * 2) Most SMP arch's #define some of these maps to be some
369 * other map specific to that arch. Therefore, the following
370 * must be #define macros, not inlines. To see why, examine
371 * the assembly code produced by the following. Note that
372 * set1() writes phys_x_map, but set2() writes x_map:
373 * int x_map, phys_x_map;
374 * #define set1(a) x_map = a
375 * inline void set2(int a) { x_map = a; }
376 * #define x_map phys_x_map
377 * main(){ set1(3); set2(5); }
378 */
379
380 extern cpumask_t cpu_possible_map;
381 extern cpumask_t cpu_online_map;
382 extern cpumask_t cpu_present_map;
383
384 #if NR_CPUS > 1
385 #define num_online_cpus() cpus_weight(cpu_online_map)
386 #define num_possible_cpus() cpus_weight(cpu_possible_map)
387 #define num_present_cpus() cpus_weight(cpu_present_map)
388 #define cpu_online(cpu) cpu_isset((cpu), cpu_online_map)
389 #define cpu_possible(cpu) cpu_isset((cpu), cpu_possible_map)
390 #define cpu_present(cpu) cpu_isset((cpu), cpu_present_map)
391 #else
392 #define num_online_cpus() 1
393 #define num_possible_cpus() 1
394 #define num_present_cpus() 1
395 #define cpu_online(cpu) ((cpu) == 0)
396 #define cpu_possible(cpu) ((cpu) == 0)
397 #define cpu_present(cpu) ((cpu) == 0)
398 #endif
399
400 #ifdef CONFIG_SMP
401 int highest_possible_processor_id(void);
402 #define any_online_cpu(mask) __any_online_cpu(&(mask))
403 int __any_online_cpu(const cpumask_t *mask);
404 #else
405 #define highest_possible_processor_id() 0
406 #define any_online_cpu(mask) 0
407 #endif
408
409 #define for_each_possible_cpu(cpu) for_each_cpu_mask((cpu), cpu_possible_map)
410 #define for_each_online_cpu(cpu) for_each_cpu_mask((cpu), cpu_online_map)
411 #define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map)
412
413 #endif /* __LINUX_CPUMASK_H */
414