Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 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 | * |
| 16 | * The available cpumask operations are: |
| 17 | * |
| 18 | * void cpu_set(cpu, mask) turn on bit 'cpu' in mask |
| 19 | * void cpu_clear(cpu, mask) turn off bit 'cpu' in mask |
| 20 | * void cpus_setall(mask) set all bits |
| 21 | * void cpus_clear(mask) clear all bits |
| 22 | * int cpu_isset(cpu, mask) true iff bit 'cpu' set in mask |
| 23 | * int cpu_test_and_set(cpu, mask) test and set bit 'cpu' in mask |
| 24 | * |
| 25 | * void cpus_and(dst, src1, src2) dst = src1 & src2 [intersection] |
| 26 | * void cpus_or(dst, src1, src2) dst = src1 | src2 [union] |
| 27 | * void cpus_xor(dst, src1, src2) dst = src1 ^ src2 |
| 28 | * void cpus_andnot(dst, src1, src2) dst = src1 & ~src2 |
| 29 | * void cpus_complement(dst, src) dst = ~src |
| 30 | * |
| 31 | * int cpus_equal(mask1, mask2) Does mask1 == mask2? |
| 32 | * int cpus_intersects(mask1, mask2) Do mask1 and mask2 intersect? |
| 33 | * int cpus_subset(mask1, mask2) Is mask1 a subset of mask2? |
| 34 | * int cpus_empty(mask) Is mask empty (no bits sets)? |
| 35 | * int cpus_full(mask) Is mask full (all bits sets)? |
| 36 | * int cpus_weight(mask) Hamming weigh - number of set bits |
| 37 | * |
| 38 | * void cpus_shift_right(dst, src, n) Shift right |
| 39 | * void cpus_shift_left(dst, src, n) Shift left |
| 40 | * |
| 41 | * int first_cpu(mask) Number lowest set bit, or NR_CPUS |
| 42 | * int next_cpu(cpu, mask) Next cpu past 'cpu', or NR_CPUS |
| 43 | * |
| 44 | * cpumask_t cpumask_of_cpu(cpu) Return cpumask with bit 'cpu' set |
| 45 | * CPU_MASK_ALL Initializer - all bits set |
| 46 | * CPU_MASK_NONE Initializer - no bits set |
| 47 | * unsigned long *cpus_addr(mask) Array of unsigned long's in mask |
| 48 | * |
| 49 | * int cpumask_scnprintf(buf, len, mask) Format cpumask for printing |
| 50 | * int cpumask_parse(ubuf, ulen, mask) Parse ascii string as cpumask |
| 51 | * int cpulist_scnprintf(buf, len, mask) Format cpumask as list for printing |
| 52 | * int cpulist_parse(buf, map) Parse ascii string as cpulist |
| 53 | * |
| 54 | * for_each_cpu_mask(cpu, mask) for-loop cpu over mask |
| 55 | * |
| 56 | * int num_online_cpus() Number of online CPUs |
| 57 | * int num_possible_cpus() Number of all possible CPUs |
| 58 | * int num_present_cpus() Number of present CPUs |
| 59 | * |
| 60 | * int cpu_online(cpu) Is some cpu online? |
| 61 | * int cpu_possible(cpu) Is some cpu possible? |
| 62 | * int cpu_present(cpu) Is some cpu present (can schedule)? |
| 63 | * |
| 64 | * int any_online_cpu(mask) First online cpu in mask |
| 65 | * |
| 66 | * for_each_cpu(cpu) for-loop cpu over cpu_possible_map |
| 67 | * for_each_online_cpu(cpu) for-loop cpu over cpu_online_map |
| 68 | * for_each_present_cpu(cpu) for-loop cpu over cpu_present_map |
| 69 | * |
| 70 | * Subtlety: |
| 71 | * 1) The 'type-checked' form of cpu_isset() causes gcc (3.3.2, anyway) |
| 72 | * to generate slightly worse code. Note for example the additional |
| 73 | * 40 lines of assembly code compiling the "for each possible cpu" |
| 74 | * loops buried in the disk_stat_read() macros calls when compiling |
| 75 | * drivers/block/genhd.c (arch i386, CONFIG_SMP=y). So use a simple |
| 76 | * one-line #define for cpu_isset(), instead of wrapping an inline |
| 77 | * inside a macro, the way we do the other calls. |
| 78 | */ |
| 79 | |
| 80 | #include <linux/kernel.h> |
| 81 | #include <linux/threads.h> |
| 82 | #include <linux/bitmap.h> |
| 83 | #include <asm/bug.h> |
| 84 | |
| 85 | typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t; |
| 86 | extern cpumask_t _unused_cpumask_arg_; |
| 87 | |
| 88 | #define cpu_set(cpu, dst) __cpu_set((cpu), &(dst)) |
| 89 | static inline void __cpu_set(int cpu, volatile cpumask_t *dstp) |
| 90 | { |
| 91 | set_bit(cpu, dstp->bits); |
| 92 | } |
| 93 | |
| 94 | #define cpu_clear(cpu, dst) __cpu_clear((cpu), &(dst)) |
| 95 | static inline void __cpu_clear(int cpu, volatile cpumask_t *dstp) |
| 96 | { |
| 97 | clear_bit(cpu, dstp->bits); |
| 98 | } |
| 99 | |
| 100 | #define cpus_setall(dst) __cpus_setall(&(dst), NR_CPUS) |
| 101 | static inline void __cpus_setall(cpumask_t *dstp, int nbits) |
| 102 | { |
| 103 | bitmap_fill(dstp->bits, nbits); |
| 104 | } |
| 105 | |
| 106 | #define cpus_clear(dst) __cpus_clear(&(dst), NR_CPUS) |
| 107 | static inline void __cpus_clear(cpumask_t *dstp, int nbits) |
| 108 | { |
| 109 | bitmap_zero(dstp->bits, nbits); |
| 110 | } |
| 111 | |
| 112 | /* No static inline type checking - see Subtlety (1) above. */ |
| 113 | #define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask).bits) |
| 114 | |
| 115 | #define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), &(cpumask)) |
| 116 | static inline int __cpu_test_and_set(int cpu, cpumask_t *addr) |
| 117 | { |
| 118 | return test_and_set_bit(cpu, addr->bits); |
| 119 | } |
| 120 | |
| 121 | #define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS) |
| 122 | static inline void __cpus_and(cpumask_t *dstp, const cpumask_t *src1p, |
| 123 | const cpumask_t *src2p, int nbits) |
| 124 | { |
| 125 | bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits); |
| 126 | } |
| 127 | |
| 128 | #define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS) |
| 129 | static inline void __cpus_or(cpumask_t *dstp, const cpumask_t *src1p, |
| 130 | const cpumask_t *src2p, int nbits) |
| 131 | { |
| 132 | bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits); |
| 133 | } |
| 134 | |
| 135 | #define cpus_xor(dst, src1, src2) __cpus_xor(&(dst), &(src1), &(src2), NR_CPUS) |
| 136 | static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p, |
| 137 | const cpumask_t *src2p, int nbits) |
| 138 | { |
| 139 | bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits); |
| 140 | } |
| 141 | |
| 142 | #define cpus_andnot(dst, src1, src2) \ |
| 143 | __cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS) |
| 144 | static inline void __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p, |
| 145 | const cpumask_t *src2p, int nbits) |
| 146 | { |
| 147 | bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits); |
| 148 | } |
| 149 | |
| 150 | #define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS) |
| 151 | static inline void __cpus_complement(cpumask_t *dstp, |
| 152 | const cpumask_t *srcp, int nbits) |
| 153 | { |
| 154 | bitmap_complement(dstp->bits, srcp->bits, nbits); |
| 155 | } |
| 156 | |
| 157 | #define cpus_equal(src1, src2) __cpus_equal(&(src1), &(src2), NR_CPUS) |
| 158 | static inline int __cpus_equal(const cpumask_t *src1p, |
| 159 | const cpumask_t *src2p, int nbits) |
| 160 | { |
| 161 | return bitmap_equal(src1p->bits, src2p->bits, nbits); |
| 162 | } |
| 163 | |
| 164 | #define cpus_intersects(src1, src2) __cpus_intersects(&(src1), &(src2), NR_CPUS) |
| 165 | static inline int __cpus_intersects(const cpumask_t *src1p, |
| 166 | const cpumask_t *src2p, int nbits) |
| 167 | { |
| 168 | return bitmap_intersects(src1p->bits, src2p->bits, nbits); |
| 169 | } |
| 170 | |
| 171 | #define cpus_subset(src1, src2) __cpus_subset(&(src1), &(src2), NR_CPUS) |
| 172 | static inline int __cpus_subset(const cpumask_t *src1p, |
| 173 | const cpumask_t *src2p, int nbits) |
| 174 | { |
| 175 | return bitmap_subset(src1p->bits, src2p->bits, nbits); |
| 176 | } |
| 177 | |
| 178 | #define cpus_empty(src) __cpus_empty(&(src), NR_CPUS) |
| 179 | static inline int __cpus_empty(const cpumask_t *srcp, int nbits) |
| 180 | { |
| 181 | return bitmap_empty(srcp->bits, nbits); |
| 182 | } |
| 183 | |
| 184 | #define cpus_full(cpumask) __cpus_full(&(cpumask), NR_CPUS) |
| 185 | static inline int __cpus_full(const cpumask_t *srcp, int nbits) |
| 186 | { |
| 187 | return bitmap_full(srcp->bits, nbits); |
| 188 | } |
| 189 | |
| 190 | #define cpus_weight(cpumask) __cpus_weight(&(cpumask), NR_CPUS) |
| 191 | static inline int __cpus_weight(const cpumask_t *srcp, int nbits) |
| 192 | { |
| 193 | return bitmap_weight(srcp->bits, nbits); |
| 194 | } |
| 195 | |
| 196 | #define cpus_shift_right(dst, src, n) \ |
| 197 | __cpus_shift_right(&(dst), &(src), (n), NR_CPUS) |
| 198 | static inline void __cpus_shift_right(cpumask_t *dstp, |
| 199 | const cpumask_t *srcp, int n, int nbits) |
| 200 | { |
| 201 | bitmap_shift_right(dstp->bits, srcp->bits, n, nbits); |
| 202 | } |
| 203 | |
| 204 | #define cpus_shift_left(dst, src, n) \ |
| 205 | __cpus_shift_left(&(dst), &(src), (n), NR_CPUS) |
| 206 | static inline void __cpus_shift_left(cpumask_t *dstp, |
| 207 | const cpumask_t *srcp, int n, int nbits) |
| 208 | { |
| 209 | bitmap_shift_left(dstp->bits, srcp->bits, n, nbits); |
| 210 | } |
| 211 | |
| 212 | #define first_cpu(src) __first_cpu(&(src), NR_CPUS) |
| 213 | static inline int __first_cpu(const cpumask_t *srcp, int nbits) |
| 214 | { |
| 215 | return min_t(int, nbits, find_first_bit(srcp->bits, nbits)); |
| 216 | } |
| 217 | |
| 218 | #define next_cpu(n, src) __next_cpu((n), &(src), NR_CPUS) |
| 219 | static inline int __next_cpu(int n, const cpumask_t *srcp, int nbits) |
| 220 | { |
| 221 | return min_t(int, nbits, find_next_bit(srcp->bits, nbits, n+1)); |
| 222 | } |
| 223 | |
| 224 | #define cpumask_of_cpu(cpu) \ |
| 225 | ({ \ |
| 226 | typeof(_unused_cpumask_arg_) m; \ |
| 227 | if (sizeof(m) == sizeof(unsigned long)) { \ |
| 228 | m.bits[0] = 1UL<<(cpu); \ |
| 229 | } else { \ |
| 230 | cpus_clear(m); \ |
| 231 | cpu_set((cpu), m); \ |
| 232 | } \ |
| 233 | m; \ |
| 234 | }) |
| 235 | |
| 236 | #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS) |
| 237 | |
| 238 | #if NR_CPUS <= BITS_PER_LONG |
| 239 | |
| 240 | #define CPU_MASK_ALL \ |
| 241 | (cpumask_t) { { \ |
| 242 | [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ |
| 243 | } } |
| 244 | |
| 245 | #else |
| 246 | |
| 247 | #define CPU_MASK_ALL \ |
| 248 | (cpumask_t) { { \ |
| 249 | [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ |
| 250 | [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ |
| 251 | } } |
| 252 | |
| 253 | #endif |
| 254 | |
| 255 | #define CPU_MASK_NONE \ |
| 256 | (cpumask_t) { { \ |
| 257 | [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ |
| 258 | } } |
| 259 | |
| 260 | #define CPU_MASK_CPU0 \ |
| 261 | (cpumask_t) { { \ |
| 262 | [0] = 1UL \ |
| 263 | } } |
| 264 | |
| 265 | #define cpus_addr(src) ((src).bits) |
| 266 | |
| 267 | #define cpumask_scnprintf(buf, len, src) \ |
| 268 | __cpumask_scnprintf((buf), (len), &(src), NR_CPUS) |
| 269 | static inline int __cpumask_scnprintf(char *buf, int len, |
| 270 | const cpumask_t *srcp, int nbits) |
| 271 | { |
| 272 | return bitmap_scnprintf(buf, len, srcp->bits, nbits); |
| 273 | } |
| 274 | |
| 275 | #define cpumask_parse(ubuf, ulen, dst) \ |
| 276 | __cpumask_parse((ubuf), (ulen), &(dst), NR_CPUS) |
| 277 | static inline int __cpumask_parse(const char __user *buf, int len, |
| 278 | cpumask_t *dstp, int nbits) |
| 279 | { |
| 280 | return bitmap_parse(buf, len, dstp->bits, nbits); |
| 281 | } |
| 282 | |
| 283 | #define cpulist_scnprintf(buf, len, src) \ |
| 284 | __cpulist_scnprintf((buf), (len), &(src), NR_CPUS) |
| 285 | static inline int __cpulist_scnprintf(char *buf, int len, |
| 286 | const cpumask_t *srcp, int nbits) |
| 287 | { |
| 288 | return bitmap_scnlistprintf(buf, len, srcp->bits, nbits); |
| 289 | } |
| 290 | |
| 291 | #define cpulist_parse(buf, dst) __cpulist_parse((buf), &(dst), NR_CPUS) |
| 292 | static inline int __cpulist_parse(const char *buf, cpumask_t *dstp, int nbits) |
| 293 | { |
| 294 | return bitmap_parselist(buf, dstp->bits, nbits); |
| 295 | } |
| 296 | |
| 297 | #if NR_CPUS > 1 |
| 298 | #define for_each_cpu_mask(cpu, mask) \ |
| 299 | for ((cpu) = first_cpu(mask); \ |
| 300 | (cpu) < NR_CPUS; \ |
| 301 | (cpu) = next_cpu((cpu), (mask))) |
| 302 | #else /* NR_CPUS == 1 */ |
| 303 | #define for_each_cpu_mask(cpu, mask) for ((cpu) = 0; (cpu) < 1; (cpu)++) |
| 304 | #endif /* NR_CPUS */ |
| 305 | |
| 306 | /* |
| 307 | * The following particular system cpumasks and operations manage |
| 308 | * possible, present and online cpus. Each of them is a fixed size |
| 309 | * bitmap of size NR_CPUS. |
| 310 | * |
| 311 | * #ifdef CONFIG_HOTPLUG_CPU |
| 312 | * cpu_possible_map - all NR_CPUS bits set |
| 313 | * cpu_present_map - has bit 'cpu' set iff cpu is populated |
| 314 | * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler |
| 315 | * #else |
| 316 | * cpu_possible_map - has bit 'cpu' set iff cpu is populated |
| 317 | * cpu_present_map - copy of cpu_possible_map |
| 318 | * cpu_online_map - has bit 'cpu' set iff cpu available to scheduler |
| 319 | * #endif |
| 320 | * |
| 321 | * In either case, NR_CPUS is fixed at compile time, as the static |
| 322 | * size of these bitmaps. The cpu_possible_map is fixed at boot |
| 323 | * time, as the set of CPU id's that it is possible might ever |
| 324 | * be plugged in at anytime during the life of that system boot. |
| 325 | * The cpu_present_map is dynamic(*), representing which CPUs |
| 326 | * are currently plugged in. And cpu_online_map is the dynamic |
| 327 | * subset of cpu_present_map, indicating those CPUs available |
| 328 | * for scheduling. |
| 329 | * |
| 330 | * If HOTPLUG is enabled, then cpu_possible_map is forced to have |
| 331 | * all NR_CPUS bits set, otherwise it is just the set of CPUs that |
| 332 | * ACPI reports present at boot. |
| 333 | * |
| 334 | * If HOTPLUG is enabled, then cpu_present_map varies dynamically, |
| 335 | * depending on what ACPI reports as currently plugged in, otherwise |
| 336 | * cpu_present_map is just a copy of cpu_possible_map. |
| 337 | * |
| 338 | * (*) Well, cpu_present_map is dynamic in the hotplug case. If not |
| 339 | * hotplug, it's a copy of cpu_possible_map, hence fixed at boot. |
| 340 | * |
| 341 | * Subtleties: |
| 342 | * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode |
| 343 | * assumption that their single CPU is online. The UP |
| 344 | * cpu_{online,possible,present}_maps are placebos. Changing them |
| 345 | * will have no useful affect on the following num_*_cpus() |
| 346 | * and cpu_*() macros in the UP case. This ugliness is a UP |
| 347 | * optimization - don't waste any instructions or memory references |
| 348 | * asking if you're online or how many CPUs there are if there is |
| 349 | * only one CPU. |
| 350 | * 2) Most SMP arch's #define some of these maps to be some |
| 351 | * other map specific to that arch. Therefore, the following |
| 352 | * must be #define macros, not inlines. To see why, examine |
| 353 | * the assembly code produced by the following. Note that |
| 354 | * set1() writes phys_x_map, but set2() writes x_map: |
| 355 | * int x_map, phys_x_map; |
| 356 | * #define set1(a) x_map = a |
| 357 | * inline void set2(int a) { x_map = a; } |
| 358 | * #define x_map phys_x_map |
| 359 | * main(){ set1(3); set2(5); } |
| 360 | */ |
| 361 | |
| 362 | extern cpumask_t cpu_possible_map; |
| 363 | extern cpumask_t cpu_online_map; |
| 364 | extern cpumask_t cpu_present_map; |
| 365 | |
| 366 | #if NR_CPUS > 1 |
| 367 | #define num_online_cpus() cpus_weight(cpu_online_map) |
| 368 | #define num_possible_cpus() cpus_weight(cpu_possible_map) |
| 369 | #define num_present_cpus() cpus_weight(cpu_present_map) |
| 370 | #define cpu_online(cpu) cpu_isset((cpu), cpu_online_map) |
| 371 | #define cpu_possible(cpu) cpu_isset((cpu), cpu_possible_map) |
| 372 | #define cpu_present(cpu) cpu_isset((cpu), cpu_present_map) |
| 373 | #else |
| 374 | #define num_online_cpus() 1 |
| 375 | #define num_possible_cpus() 1 |
| 376 | #define num_present_cpus() 1 |
| 377 | #define cpu_online(cpu) ((cpu) == 0) |
| 378 | #define cpu_possible(cpu) ((cpu) == 0) |
| 379 | #define cpu_present(cpu) ((cpu) == 0) |
| 380 | #endif |
| 381 | |
| 382 | #define any_online_cpu(mask) \ |
| 383 | ({ \ |
| 384 | int cpu; \ |
| 385 | for_each_cpu_mask(cpu, (mask)) \ |
| 386 | if (cpu_online(cpu)) \ |
| 387 | break; \ |
| 388 | cpu; \ |
| 389 | }) |
| 390 | |
| 391 | #define for_each_cpu(cpu) for_each_cpu_mask((cpu), cpu_possible_map) |
| 392 | #define for_each_online_cpu(cpu) for_each_cpu_mask((cpu), cpu_online_map) |
| 393 | #define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map) |
| 394 | |
| 395 | #endif /* __LINUX_CPUMASK_H */ |