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)) 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)) 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) 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) 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)) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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) 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
