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_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 #include <asm/bug.h> 88 89 typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t; 90 extern cpumask_t _unused_cpumask_arg_; 91 92 #define cpu_set(cpu, dst) __cpu_set((cpu), &(dst)) 93 static inline void __cpu_set(int cpu, volatile cpumask_t *dstp) 94 { 95 set_bit(cpu, dstp->bits); 96 } 97 98 #define cpu_clear(cpu, dst) __cpu_clear((cpu), &(dst)) 99 static inline void __cpu_clear(int cpu, volatile cpumask_t *dstp) 100 { 101 clear_bit(cpu, dstp->bits); 102 } 103 104 #define cpus_setall(dst) __cpus_setall(&(dst), NR_CPUS) 105 static inline void __cpus_setall(cpumask_t *dstp, int nbits) 106 { 107 bitmap_fill(dstp->bits, nbits); 108 } 109 110 #define cpus_clear(dst) __cpus_clear(&(dst), NR_CPUS) 111 static inline void __cpus_clear(cpumask_t *dstp, int nbits) 112 { 113 bitmap_zero(dstp->bits, nbits); 114 } 115 116 /* No static inline type checking - see Subtlety (1) above. */ 117 #define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask).bits) 118 119 #define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), &(cpumask)) 120 static inline int __cpu_test_and_set(int cpu, cpumask_t *addr) 121 { 122 return test_and_set_bit(cpu, addr->bits); 123 } 124 125 #define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS) 126 static inline void __cpus_and(cpumask_t *dstp, const cpumask_t *src1p, 127 const cpumask_t *src2p, int nbits) 128 { 129 bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits); 130 } 131 132 #define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS) 133 static inline void __cpus_or(cpumask_t *dstp, const cpumask_t *src1p, 134 const cpumask_t *src2p, int nbits) 135 { 136 bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits); 137 } 138 139 #define cpus_xor(dst, src1, src2) __cpus_xor(&(dst), &(src1), &(src2), NR_CPUS) 140 static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p, 141 const cpumask_t *src2p, int nbits) 142 { 143 bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits); 144 } 145 146 #define cpus_andnot(dst, src1, src2) \ 147 __cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS) 148 static inline void __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p, 149 const cpumask_t *src2p, int nbits) 150 { 151 bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits); 152 } 153 154 #define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS) 155 static inline void __cpus_complement(cpumask_t *dstp, 156 const cpumask_t *srcp, int nbits) 157 { 158 bitmap_complement(dstp->bits, srcp->bits, nbits); 159 } 160 161 #define cpus_equal(src1, src2) __cpus_equal(&(src1), &(src2), NR_CPUS) 162 static inline int __cpus_equal(const cpumask_t *src1p, 163 const cpumask_t *src2p, int nbits) 164 { 165 return bitmap_equal(src1p->bits, src2p->bits, nbits); 166 } 167 168 #define cpus_intersects(src1, src2) __cpus_intersects(&(src1), &(src2), NR_CPUS) 169 static inline int __cpus_intersects(const cpumask_t *src1p, 170 const cpumask_t *src2p, int nbits) 171 { 172 return bitmap_intersects(src1p->bits, src2p->bits, nbits); 173 } 174 175 #define cpus_subset(src1, src2) __cpus_subset(&(src1), &(src2), NR_CPUS) 176 static inline int __cpus_subset(const cpumask_t *src1p, 177 const cpumask_t *src2p, int nbits) 178 { 179 return bitmap_subset(src1p->bits, src2p->bits, nbits); 180 } 181 182 #define cpus_empty(src) __cpus_empty(&(src), NR_CPUS) 183 static inline int __cpus_empty(const cpumask_t *srcp, int nbits) 184 { 185 return bitmap_empty(srcp->bits, nbits); 186 } 187 188 #define cpus_full(cpumask) __cpus_full(&(cpumask), NR_CPUS) 189 static inline int __cpus_full(const cpumask_t *srcp, int nbits) 190 { 191 return bitmap_full(srcp->bits, nbits); 192 } 193 194 #define cpus_weight(cpumask) __cpus_weight(&(cpumask), NR_CPUS) 195 static inline int __cpus_weight(const cpumask_t *srcp, int nbits) 196 { 197 return bitmap_weight(srcp->bits, nbits); 198 } 199 200 #define cpus_shift_right(dst, src, n) \ 201 __cpus_shift_right(&(dst), &(src), (n), NR_CPUS) 202 static inline void __cpus_shift_right(cpumask_t *dstp, 203 const cpumask_t *srcp, int n, int nbits) 204 { 205 bitmap_shift_right(dstp->bits, srcp->bits, n, nbits); 206 } 207 208 #define cpus_shift_left(dst, src, n) \ 209 __cpus_shift_left(&(dst), &(src), (n), NR_CPUS) 210 static inline void __cpus_shift_left(cpumask_t *dstp, 211 const cpumask_t *srcp, int n, int nbits) 212 { 213 bitmap_shift_left(dstp->bits, srcp->bits, n, nbits); 214 } 215 216 #define first_cpu(src) __first_cpu(&(src), NR_CPUS) 217 static inline int __first_cpu(const cpumask_t *srcp, int nbits) 218 { 219 return min_t(int, nbits, find_first_bit(srcp->bits, nbits)); 220 } 221 222 #define next_cpu(n, src) __next_cpu((n), &(src), NR_CPUS) 223 static inline int __next_cpu(int n, const cpumask_t *srcp, int nbits) 224 { 225 return min_t(int, nbits, find_next_bit(srcp->bits, nbits, n+1)); 226 } 227 228 #define cpumask_of_cpu(cpu) \ 229 ({ \ 230 typeof(_unused_cpumask_arg_) m; \ 231 if (sizeof(m) == sizeof(unsigned long)) { \ 232 m.bits[0] = 1UL<<(cpu); \ 233 } else { \ 234 cpus_clear(m); \ 235 cpu_set((cpu), m); \ 236 } \ 237 m; \ 238 }) 239 240 #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS) 241 242 #if NR_CPUS <= BITS_PER_LONG 243 244 #define CPU_MASK_ALL \ 245 (cpumask_t) { { \ 246 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ 247 } } 248 249 #else 250 251 #define CPU_MASK_ALL \ 252 (cpumask_t) { { \ 253 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 254 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ 255 } } 256 257 #endif 258 259 #define CPU_MASK_NONE \ 260 (cpumask_t) { { \ 261 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 262 } } 263 264 #define CPU_MASK_CPU0 \ 265 (cpumask_t) { { \ 266 [0] = 1UL \ 267 } } 268 269 #define cpus_addr(src) ((src).bits) 270 271 #define cpumask_scnprintf(buf, len, src) \ 272 __cpumask_scnprintf((buf), (len), &(src), NR_CPUS) 273 static inline int __cpumask_scnprintf(char *buf, int len, 274 const cpumask_t *srcp, int nbits) 275 { 276 return bitmap_scnprintf(buf, len, srcp->bits, nbits); 277 } 278 279 #define cpumask_parse(ubuf, ulen, dst) \ 280 __cpumask_parse((ubuf), (ulen), &(dst), NR_CPUS) 281 static inline int __cpumask_parse(const char __user *buf, int len, 282 cpumask_t *dstp, int nbits) 283 { 284 return bitmap_parse(buf, len, dstp->bits, nbits); 285 } 286 287 #define cpulist_scnprintf(buf, len, src) \ 288 __cpulist_scnprintf((buf), (len), &(src), NR_CPUS) 289 static inline int __cpulist_scnprintf(char *buf, int len, 290 const cpumask_t *srcp, int nbits) 291 { 292 return bitmap_scnlistprintf(buf, len, srcp->bits, nbits); 293 } 294 295 #define cpulist_parse(buf, dst) __cpulist_parse((buf), &(dst), NR_CPUS) 296 static inline int __cpulist_parse(const char *buf, cpumask_t *dstp, int nbits) 297 { 298 return bitmap_parselist(buf, dstp->bits, nbits); 299 } 300 301 #define cpu_remap(oldbit, old, new) \ 302 __cpu_remap((oldbit), &(old), &(new), NR_CPUS) 303 static inline int __cpu_remap(int oldbit, 304 const cpumask_t *oldp, const cpumask_t *newp, int nbits) 305 { 306 return bitmap_bitremap(oldbit, oldp->bits, newp->bits, nbits); 307 } 308 309 #define cpus_remap(dst, src, old, new) \ 310 __cpus_remap(&(dst), &(src), &(old), &(new), NR_CPUS) 311 static inline void __cpus_remap(cpumask_t *dstp, const cpumask_t *srcp, 312 const cpumask_t *oldp, const cpumask_t *newp, int nbits) 313 { 314 bitmap_remap(dstp->bits, srcp->bits, oldp->bits, newp->bits, nbits); 315 } 316 317 #if NR_CPUS > 1 318 #define for_each_cpu_mask(cpu, mask) \ 319 for ((cpu) = first_cpu(mask); \ 320 (cpu) < NR_CPUS; \ 321 (cpu) = next_cpu((cpu), (mask))) 322 #else /* NR_CPUS == 1 */ 323 #define for_each_cpu_mask(cpu, mask) for ((cpu) = 0; (cpu) < 1; (cpu)++) 324 #endif /* NR_CPUS */ 325 326 /* 327 * The following particular system cpumasks and operations manage 328 * possible, present and online cpus. Each of them is a fixed size 329 * bitmap of size NR_CPUS. 330 * 331 * #ifdef CONFIG_HOTPLUG_CPU 332 * cpu_possible_map - all NR_CPUS bits set 333 * cpu_present_map - has bit 'cpu' set iff cpu is populated 334 * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler 335 * #else 336 * cpu_possible_map - has bit 'cpu' set iff cpu is populated 337 * cpu_present_map - copy of cpu_possible_map 338 * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler 339 * #endif 340 * 341 * In either case, NR_CPUS is fixed at compile time, as the static 342 * size of these bitmaps. The cpu_possible_map is fixed at boot 343 * time, as the set of CPU id's that it is possible might ever 344 * be plugged in at anytime during the life of that system boot. 345 * The cpu_present_map is dynamic(*), representing which CPUs 346 * are currently plugged in. And cpu_online_map is the dynamic 347 * subset of cpu_present_map, indicating those CPUs available 348 * for scheduling. 349 * 350 * If HOTPLUG is enabled, then cpu_possible_map is forced to have 351 * all NR_CPUS bits set, otherwise it is just the set of CPUs that 352 * ACPI reports present at boot. 353 * 354 * If HOTPLUG is enabled, then cpu_present_map varies dynamically, 355 * depending on what ACPI reports as currently plugged in, otherwise 356 * cpu_present_map is just a copy of cpu_possible_map. 357 * 358 * (*) Well, cpu_present_map is dynamic in the hotplug case. If not 359 * hotplug, it's a copy of cpu_possible_map, hence fixed at boot. 360 * 361 * Subtleties: 362 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode 363 * assumption that their single CPU is online. The UP 364 * cpu_{online,possible,present}_maps are placebos. Changing them 365 * will have no useful affect on the following num_*_cpus() 366 * and cpu_*() macros in the UP case. This ugliness is a UP 367 * optimization - don't waste any instructions or memory references 368 * asking if you're online or how many CPUs there are if there is 369 * only one CPU. 370 * 2) Most SMP arch's #define some of these maps to be some 371 * other map specific to that arch. Therefore, the following 372 * must be #define macros, not inlines. To see why, examine 373 * the assembly code produced by the following. Note that 374 * set1() writes phys_x_map, but set2() writes x_map: 375 * int x_map, phys_x_map; 376 * #define set1(a) x_map = a 377 * inline void set2(int a) { x_map = a; } 378 * #define x_map phys_x_map 379 * main(){ set1(3); set2(5); } 380 */ 381 382 extern cpumask_t cpu_possible_map; 383 extern cpumask_t cpu_online_map; 384 extern cpumask_t cpu_present_map; 385 386 #if NR_CPUS > 1 387 #define num_online_cpus() cpus_weight(cpu_online_map) 388 #define num_possible_cpus() cpus_weight(cpu_possible_map) 389 #define num_present_cpus() cpus_weight(cpu_present_map) 390 #define cpu_online(cpu) cpu_isset((cpu), cpu_online_map) 391 #define cpu_possible(cpu) cpu_isset((cpu), cpu_possible_map) 392 #define cpu_present(cpu) cpu_isset((cpu), cpu_present_map) 393 #else 394 #define num_online_cpus() 1 395 #define num_possible_cpus() 1 396 #define num_present_cpus() 1 397 #define cpu_online(cpu) ((cpu) == 0) 398 #define cpu_possible(cpu) ((cpu) == 0) 399 #define cpu_present(cpu) ((cpu) == 0) 400 #endif 401 402 #define any_online_cpu(mask) \ 403 ({ \ 404 int cpu; \ 405 for_each_cpu_mask(cpu, (mask)) \ 406 if (cpu_online(cpu)) \ 407 break; \ 408 cpu; \ 409 }) 410 411 #define for_each_cpu(cpu) for_each_cpu_mask((cpu), cpu_possible_map) 412 #define for_each_online_cpu(cpu) for_each_cpu_mask((cpu), cpu_online_map) 413 #define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map) 414 415 /* Find the highest possible smp_processor_id() */ 416 #define highest_possible_processor_id() \ 417 ({ \ 418 unsigned int cpu, highest = 0; \ 419 for_each_cpu_mask(cpu, cpu_possible_map) \ 420 highest = cpu; \ 421 highest; \ 422 }) 423 424 425 #endif /* __LINUX_CPUMASK_H */ 426