1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __LINUX_CPUMASK_H 3 #define __LINUX_CPUMASK_H 4 5 /* 6 * Cpumasks provide a bitmap suitable for representing the 7 * set of CPU's in a system, one bit position per CPU number. In general, 8 * only nr_cpu_ids (<= NR_CPUS) bits are valid. 9 */ 10 #include <linux/kernel.h> 11 #include <linux/threads.h> 12 #include <linux/bitmap.h> 13 #include <linux/atomic.h> 14 #include <linux/bug.h> 15 16 /* Don't assign or return these: may not be this big! */ 17 typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t; 18 19 /** 20 * cpumask_bits - get the bits in a cpumask 21 * @maskp: the struct cpumask * 22 * 23 * You should only assume nr_cpu_ids bits of this mask are valid. This is 24 * a macro so it's const-correct. 25 */ 26 #define cpumask_bits(maskp) ((maskp)->bits) 27 28 /** 29 * cpumask_pr_args - printf args to output a cpumask 30 * @maskp: cpumask to be printed 31 * 32 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask. 33 */ 34 #define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp) 35 36 #if NR_CPUS == 1 37 #define nr_cpu_ids 1U 38 #else 39 extern unsigned int nr_cpu_ids; 40 #endif 41 42 #ifdef CONFIG_CPUMASK_OFFSTACK 43 /* Assuming NR_CPUS is huge, a runtime limit is more efficient. Also, 44 * not all bits may be allocated. */ 45 #define nr_cpumask_bits nr_cpu_ids 46 #else 47 #define nr_cpumask_bits ((unsigned int)NR_CPUS) 48 #endif 49 50 /* 51 * The following particular system cpumasks and operations manage 52 * possible, present, active and online cpus. 53 * 54 * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable 55 * cpu_present_mask - has bit 'cpu' set iff cpu is populated 56 * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler 57 * cpu_active_mask - has bit 'cpu' set iff cpu available to migration 58 * 59 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online. 60 * 61 * The cpu_possible_mask is fixed at boot time, as the set of CPU id's 62 * that it is possible might ever be plugged in at anytime during the 63 * life of that system boot. The cpu_present_mask is dynamic(*), 64 * representing which CPUs are currently plugged in. And 65 * cpu_online_mask is the dynamic subset of cpu_present_mask, 66 * indicating those CPUs available for scheduling. 67 * 68 * If HOTPLUG is enabled, then cpu_possible_mask is forced to have 69 * all NR_CPUS bits set, otherwise it is just the set of CPUs that 70 * ACPI reports present at boot. 71 * 72 * If HOTPLUG is enabled, then cpu_present_mask varies dynamically, 73 * depending on what ACPI reports as currently plugged in, otherwise 74 * cpu_present_mask is just a copy of cpu_possible_mask. 75 * 76 * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not 77 * hotplug, it's a copy of cpu_possible_mask, hence fixed at boot. 78 * 79 * Subtleties: 80 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode 81 * assumption that their single CPU is online. The UP 82 * cpu_{online,possible,present}_masks are placebos. Changing them 83 * will have no useful affect on the following num_*_cpus() 84 * and cpu_*() macros in the UP case. This ugliness is a UP 85 * optimization - don't waste any instructions or memory references 86 * asking if you're online or how many CPUs there are if there is 87 * only one CPU. 88 */ 89 90 extern struct cpumask __cpu_possible_mask; 91 extern struct cpumask __cpu_online_mask; 92 extern struct cpumask __cpu_present_mask; 93 extern struct cpumask __cpu_active_mask; 94 #define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask) 95 #define cpu_online_mask ((const struct cpumask *)&__cpu_online_mask) 96 #define cpu_present_mask ((const struct cpumask *)&__cpu_present_mask) 97 #define cpu_active_mask ((const struct cpumask *)&__cpu_active_mask) 98 99 extern atomic_t __num_online_cpus; 100 101 #if NR_CPUS > 1 102 /** 103 * num_online_cpus() - Read the number of online CPUs 104 * 105 * Despite the fact that __num_online_cpus is of type atomic_t, this 106 * interface gives only a momentary snapshot and is not protected against 107 * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held 108 * region. 109 */ 110 static inline unsigned int num_online_cpus(void) 111 { 112 return atomic_read(&__num_online_cpus); 113 } 114 #define num_possible_cpus() cpumask_weight(cpu_possible_mask) 115 #define num_present_cpus() cpumask_weight(cpu_present_mask) 116 #define num_active_cpus() cpumask_weight(cpu_active_mask) 117 #define cpu_online(cpu) cpumask_test_cpu((cpu), cpu_online_mask) 118 #define cpu_possible(cpu) cpumask_test_cpu((cpu), cpu_possible_mask) 119 #define cpu_present(cpu) cpumask_test_cpu((cpu), cpu_present_mask) 120 #define cpu_active(cpu) cpumask_test_cpu((cpu), cpu_active_mask) 121 #else 122 #define num_online_cpus() 1U 123 #define num_possible_cpus() 1U 124 #define num_present_cpus() 1U 125 #define num_active_cpus() 1U 126 #define cpu_online(cpu) ((cpu) == 0) 127 #define cpu_possible(cpu) ((cpu) == 0) 128 #define cpu_present(cpu) ((cpu) == 0) 129 #define cpu_active(cpu) ((cpu) == 0) 130 #endif 131 132 extern cpumask_t cpus_booted_once_mask; 133 134 static inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits) 135 { 136 #ifdef CONFIG_DEBUG_PER_CPU_MAPS 137 WARN_ON_ONCE(cpu >= bits); 138 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */ 139 } 140 141 /* verify cpu argument to cpumask_* operators */ 142 static inline unsigned int cpumask_check(unsigned int cpu) 143 { 144 cpu_max_bits_warn(cpu, nr_cpumask_bits); 145 return cpu; 146 } 147 148 #if NR_CPUS == 1 149 /* Uniprocessor. Assume all masks are "1". */ 150 static inline unsigned int cpumask_first(const struct cpumask *srcp) 151 { 152 return 0; 153 } 154 155 static inline unsigned int cpumask_last(const struct cpumask *srcp) 156 { 157 return 0; 158 } 159 160 /* Valid inputs for n are -1 and 0. */ 161 static inline unsigned int cpumask_next(int n, const struct cpumask *srcp) 162 { 163 return n+1; 164 } 165 166 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) 167 { 168 return n+1; 169 } 170 171 static inline unsigned int cpumask_next_and(int n, 172 const struct cpumask *srcp, 173 const struct cpumask *andp) 174 { 175 return n+1; 176 } 177 178 static inline unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, 179 int start, bool wrap) 180 { 181 /* cpu0 unless stop condition, wrap and at cpu0, then nr_cpumask_bits */ 182 return (wrap && n == 0); 183 } 184 185 /* cpu must be a valid cpu, ie 0, so there's no other choice. */ 186 static inline unsigned int cpumask_any_but(const struct cpumask *mask, 187 unsigned int cpu) 188 { 189 return 1; 190 } 191 192 static inline unsigned int cpumask_local_spread(unsigned int i, int node) 193 { 194 return 0; 195 } 196 197 static inline int cpumask_any_and_distribute(const struct cpumask *src1p, 198 const struct cpumask *src2p) { 199 return cpumask_next_and(-1, src1p, src2p); 200 } 201 202 static inline int cpumask_any_distribute(const struct cpumask *srcp) 203 { 204 return cpumask_first(srcp); 205 } 206 207 #define for_each_cpu(cpu, mask) \ 208 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) 209 #define for_each_cpu_not(cpu, mask) \ 210 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) 211 #define for_each_cpu_wrap(cpu, mask, start) \ 212 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)(start)) 213 #define for_each_cpu_and(cpu, mask1, mask2) \ 214 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask1, (void)mask2) 215 #else 216 /** 217 * cpumask_first - get the first cpu in a cpumask 218 * @srcp: the cpumask pointer 219 * 220 * Returns >= nr_cpu_ids if no cpus set. 221 */ 222 static inline unsigned int cpumask_first(const struct cpumask *srcp) 223 { 224 return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits); 225 } 226 227 /** 228 * cpumask_last - get the last CPU in a cpumask 229 * @srcp: - the cpumask pointer 230 * 231 * Returns >= nr_cpumask_bits if no CPUs set. 232 */ 233 static inline unsigned int cpumask_last(const struct cpumask *srcp) 234 { 235 return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits); 236 } 237 238 unsigned int cpumask_next(int n, const struct cpumask *srcp); 239 240 /** 241 * cpumask_next_zero - get the next unset cpu in a cpumask 242 * @n: the cpu prior to the place to search (ie. return will be > @n) 243 * @srcp: the cpumask pointer 244 * 245 * Returns >= nr_cpu_ids if no further cpus unset. 246 */ 247 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) 248 { 249 /* -1 is a legal arg here. */ 250 if (n != -1) 251 cpumask_check(n); 252 return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1); 253 } 254 255 int cpumask_next_and(int n, const struct cpumask *, const struct cpumask *); 256 int cpumask_any_but(const struct cpumask *mask, unsigned int cpu); 257 unsigned int cpumask_local_spread(unsigned int i, int node); 258 int cpumask_any_and_distribute(const struct cpumask *src1p, 259 const struct cpumask *src2p); 260 int cpumask_any_distribute(const struct cpumask *srcp); 261 262 /** 263 * for_each_cpu - iterate over every cpu in a mask 264 * @cpu: the (optionally unsigned) integer iterator 265 * @mask: the cpumask pointer 266 * 267 * After the loop, cpu is >= nr_cpu_ids. 268 */ 269 #define for_each_cpu(cpu, mask) \ 270 for ((cpu) = -1; \ 271 (cpu) = cpumask_next((cpu), (mask)), \ 272 (cpu) < nr_cpu_ids;) 273 274 /** 275 * for_each_cpu_not - iterate over every cpu in a complemented mask 276 * @cpu: the (optionally unsigned) integer iterator 277 * @mask: the cpumask pointer 278 * 279 * After the loop, cpu is >= nr_cpu_ids. 280 */ 281 #define for_each_cpu_not(cpu, mask) \ 282 for ((cpu) = -1; \ 283 (cpu) = cpumask_next_zero((cpu), (mask)), \ 284 (cpu) < nr_cpu_ids;) 285 286 extern int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap); 287 288 /** 289 * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location 290 * @cpu: the (optionally unsigned) integer iterator 291 * @mask: the cpumask poiter 292 * @start: the start location 293 * 294 * The implementation does not assume any bit in @mask is set (including @start). 295 * 296 * After the loop, cpu is >= nr_cpu_ids. 297 */ 298 #define for_each_cpu_wrap(cpu, mask, start) \ 299 for ((cpu) = cpumask_next_wrap((start)-1, (mask), (start), false); \ 300 (cpu) < nr_cpumask_bits; \ 301 (cpu) = cpumask_next_wrap((cpu), (mask), (start), true)) 302 303 /** 304 * for_each_cpu_and - iterate over every cpu in both masks 305 * @cpu: the (optionally unsigned) integer iterator 306 * @mask1: the first cpumask pointer 307 * @mask2: the second cpumask pointer 308 * 309 * This saves a temporary CPU mask in many places. It is equivalent to: 310 * struct cpumask tmp; 311 * cpumask_and(&tmp, &mask1, &mask2); 312 * for_each_cpu(cpu, &tmp) 313 * ... 314 * 315 * After the loop, cpu is >= nr_cpu_ids. 316 */ 317 #define for_each_cpu_and(cpu, mask1, mask2) \ 318 for ((cpu) = -1; \ 319 (cpu) = cpumask_next_and((cpu), (mask1), (mask2)), \ 320 (cpu) < nr_cpu_ids;) 321 #endif /* SMP */ 322 323 #define CPU_BITS_NONE \ 324 { \ 325 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 326 } 327 328 #define CPU_BITS_CPU0 \ 329 { \ 330 [0] = 1UL \ 331 } 332 333 /** 334 * cpumask_set_cpu - set a cpu in a cpumask 335 * @cpu: cpu number (< nr_cpu_ids) 336 * @dstp: the cpumask pointer 337 */ 338 static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 339 { 340 set_bit(cpumask_check(cpu), cpumask_bits(dstp)); 341 } 342 343 static inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 344 { 345 __set_bit(cpumask_check(cpu), cpumask_bits(dstp)); 346 } 347 348 349 /** 350 * cpumask_clear_cpu - clear a cpu in a cpumask 351 * @cpu: cpu number (< nr_cpu_ids) 352 * @dstp: the cpumask pointer 353 */ 354 static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp) 355 { 356 clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); 357 } 358 359 static inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp) 360 { 361 __clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); 362 } 363 364 /** 365 * cpumask_test_cpu - test for a cpu in a cpumask 366 * @cpu: cpu number (< nr_cpu_ids) 367 * @cpumask: the cpumask pointer 368 * 369 * Returns 1 if @cpu is set in @cpumask, else returns 0 370 */ 371 static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask) 372 { 373 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask))); 374 } 375 376 /** 377 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask 378 * @cpu: cpu number (< nr_cpu_ids) 379 * @cpumask: the cpumask pointer 380 * 381 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0 382 * 383 * test_and_set_bit wrapper for cpumasks. 384 */ 385 static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask) 386 { 387 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 388 } 389 390 /** 391 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask 392 * @cpu: cpu number (< nr_cpu_ids) 393 * @cpumask: the cpumask pointer 394 * 395 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0 396 * 397 * test_and_clear_bit wrapper for cpumasks. 398 */ 399 static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask) 400 { 401 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 402 } 403 404 /** 405 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask 406 * @dstp: the cpumask pointer 407 */ 408 static inline void cpumask_setall(struct cpumask *dstp) 409 { 410 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits); 411 } 412 413 /** 414 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask 415 * @dstp: the cpumask pointer 416 */ 417 static inline void cpumask_clear(struct cpumask *dstp) 418 { 419 bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits); 420 } 421 422 /** 423 * cpumask_and - *dstp = *src1p & *src2p 424 * @dstp: the cpumask result 425 * @src1p: the first input 426 * @src2p: the second input 427 * 428 * If *@dstp is empty, returns 0, else returns 1 429 */ 430 static inline int cpumask_and(struct cpumask *dstp, 431 const struct cpumask *src1p, 432 const struct cpumask *src2p) 433 { 434 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p), 435 cpumask_bits(src2p), nr_cpumask_bits); 436 } 437 438 /** 439 * cpumask_or - *dstp = *src1p | *src2p 440 * @dstp: the cpumask result 441 * @src1p: the first input 442 * @src2p: the second input 443 */ 444 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p, 445 const struct cpumask *src2p) 446 { 447 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p), 448 cpumask_bits(src2p), nr_cpumask_bits); 449 } 450 451 /** 452 * cpumask_xor - *dstp = *src1p ^ *src2p 453 * @dstp: the cpumask result 454 * @src1p: the first input 455 * @src2p: the second input 456 */ 457 static inline void cpumask_xor(struct cpumask *dstp, 458 const struct cpumask *src1p, 459 const struct cpumask *src2p) 460 { 461 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p), 462 cpumask_bits(src2p), nr_cpumask_bits); 463 } 464 465 /** 466 * cpumask_andnot - *dstp = *src1p & ~*src2p 467 * @dstp: the cpumask result 468 * @src1p: the first input 469 * @src2p: the second input 470 * 471 * If *@dstp is empty, returns 0, else returns 1 472 */ 473 static inline int cpumask_andnot(struct cpumask *dstp, 474 const struct cpumask *src1p, 475 const struct cpumask *src2p) 476 { 477 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p), 478 cpumask_bits(src2p), nr_cpumask_bits); 479 } 480 481 /** 482 * cpumask_complement - *dstp = ~*srcp 483 * @dstp: the cpumask result 484 * @srcp: the input to invert 485 */ 486 static inline void cpumask_complement(struct cpumask *dstp, 487 const struct cpumask *srcp) 488 { 489 bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp), 490 nr_cpumask_bits); 491 } 492 493 /** 494 * cpumask_equal - *src1p == *src2p 495 * @src1p: the first input 496 * @src2p: the second input 497 */ 498 static inline bool cpumask_equal(const struct cpumask *src1p, 499 const struct cpumask *src2p) 500 { 501 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p), 502 nr_cpumask_bits); 503 } 504 505 /** 506 * cpumask_or_equal - *src1p | *src2p == *src3p 507 * @src1p: the first input 508 * @src2p: the second input 509 * @src3p: the third input 510 */ 511 static inline bool cpumask_or_equal(const struct cpumask *src1p, 512 const struct cpumask *src2p, 513 const struct cpumask *src3p) 514 { 515 return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p), 516 cpumask_bits(src3p), nr_cpumask_bits); 517 } 518 519 /** 520 * cpumask_intersects - (*src1p & *src2p) != 0 521 * @src1p: the first input 522 * @src2p: the second input 523 */ 524 static inline bool cpumask_intersects(const struct cpumask *src1p, 525 const struct cpumask *src2p) 526 { 527 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p), 528 nr_cpumask_bits); 529 } 530 531 /** 532 * cpumask_subset - (*src1p & ~*src2p) == 0 533 * @src1p: the first input 534 * @src2p: the second input 535 * 536 * Returns 1 if *@src1p is a subset of *@src2p, else returns 0 537 */ 538 static inline int cpumask_subset(const struct cpumask *src1p, 539 const struct cpumask *src2p) 540 { 541 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p), 542 nr_cpumask_bits); 543 } 544 545 /** 546 * cpumask_empty - *srcp == 0 547 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear. 548 */ 549 static inline bool cpumask_empty(const struct cpumask *srcp) 550 { 551 return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits); 552 } 553 554 /** 555 * cpumask_full - *srcp == 0xFFFFFFFF... 556 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set. 557 */ 558 static inline bool cpumask_full(const struct cpumask *srcp) 559 { 560 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits); 561 } 562 563 /** 564 * cpumask_weight - Count of bits in *srcp 565 * @srcp: the cpumask to count bits (< nr_cpu_ids) in. 566 */ 567 static inline unsigned int cpumask_weight(const struct cpumask *srcp) 568 { 569 return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits); 570 } 571 572 /** 573 * cpumask_shift_right - *dstp = *srcp >> n 574 * @dstp: the cpumask result 575 * @srcp: the input to shift 576 * @n: the number of bits to shift by 577 */ 578 static inline void cpumask_shift_right(struct cpumask *dstp, 579 const struct cpumask *srcp, int n) 580 { 581 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n, 582 nr_cpumask_bits); 583 } 584 585 /** 586 * cpumask_shift_left - *dstp = *srcp << n 587 * @dstp: the cpumask result 588 * @srcp: the input to shift 589 * @n: the number of bits to shift by 590 */ 591 static inline void cpumask_shift_left(struct cpumask *dstp, 592 const struct cpumask *srcp, int n) 593 { 594 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n, 595 nr_cpumask_bits); 596 } 597 598 /** 599 * cpumask_copy - *dstp = *srcp 600 * @dstp: the result 601 * @srcp: the input cpumask 602 */ 603 static inline void cpumask_copy(struct cpumask *dstp, 604 const struct cpumask *srcp) 605 { 606 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits); 607 } 608 609 /** 610 * cpumask_any - pick a "random" cpu from *srcp 611 * @srcp: the input cpumask 612 * 613 * Returns >= nr_cpu_ids if no cpus set. 614 */ 615 #define cpumask_any(srcp) cpumask_first(srcp) 616 617 /** 618 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2 619 * @src1p: the first input 620 * @src2p: the second input 621 * 622 * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and(). 623 */ 624 #define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p)) 625 626 /** 627 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2 628 * @mask1: the first input cpumask 629 * @mask2: the second input cpumask 630 * 631 * Returns >= nr_cpu_ids if no cpus set. 632 */ 633 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2)) 634 635 /** 636 * cpumask_of - the cpumask containing just a given cpu 637 * @cpu: the cpu (<= nr_cpu_ids) 638 */ 639 #define cpumask_of(cpu) (get_cpu_mask(cpu)) 640 641 /** 642 * cpumask_parse_user - extract a cpumask from a user string 643 * @buf: the buffer to extract from 644 * @len: the length of the buffer 645 * @dstp: the cpumask to set. 646 * 647 * Returns -errno, or 0 for success. 648 */ 649 static inline int cpumask_parse_user(const char __user *buf, int len, 650 struct cpumask *dstp) 651 { 652 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits); 653 } 654 655 /** 656 * cpumask_parselist_user - extract a cpumask from a user string 657 * @buf: the buffer to extract from 658 * @len: the length of the buffer 659 * @dstp: the cpumask to set. 660 * 661 * Returns -errno, or 0 for success. 662 */ 663 static inline int cpumask_parselist_user(const char __user *buf, int len, 664 struct cpumask *dstp) 665 { 666 return bitmap_parselist_user(buf, len, cpumask_bits(dstp), 667 nr_cpumask_bits); 668 } 669 670 /** 671 * cpumask_parse - extract a cpumask from a string 672 * @buf: the buffer to extract from 673 * @dstp: the cpumask to set. 674 * 675 * Returns -errno, or 0 for success. 676 */ 677 static inline int cpumask_parse(const char *buf, struct cpumask *dstp) 678 { 679 return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits); 680 } 681 682 /** 683 * cpulist_parse - extract a cpumask from a user string of ranges 684 * @buf: the buffer to extract from 685 * @dstp: the cpumask to set. 686 * 687 * Returns -errno, or 0 for success. 688 */ 689 static inline int cpulist_parse(const char *buf, struct cpumask *dstp) 690 { 691 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits); 692 } 693 694 /** 695 * cpumask_size - size to allocate for a 'struct cpumask' in bytes 696 */ 697 static inline unsigned int cpumask_size(void) 698 { 699 return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long); 700 } 701 702 /* 703 * cpumask_var_t: struct cpumask for stack usage. 704 * 705 * Oh, the wicked games we play! In order to make kernel coding a 706 * little more difficult, we typedef cpumask_var_t to an array or a 707 * pointer: doing &mask on an array is a noop, so it still works. 708 * 709 * ie. 710 * cpumask_var_t tmpmask; 711 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 712 * return -ENOMEM; 713 * 714 * ... use 'tmpmask' like a normal struct cpumask * ... 715 * 716 * free_cpumask_var(tmpmask); 717 * 718 * 719 * However, one notable exception is there. alloc_cpumask_var() allocates 720 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has 721 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t. 722 * 723 * cpumask_var_t tmpmask; 724 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 725 * return -ENOMEM; 726 * 727 * var = *tmpmask; 728 * 729 * This code makes NR_CPUS length memcopy and brings to a memory corruption. 730 * cpumask_copy() provide safe copy functionality. 731 * 732 * Note that there is another evil here: If you define a cpumask_var_t 733 * as a percpu variable then the way to obtain the address of the cpumask 734 * structure differently influences what this_cpu_* operation needs to be 735 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use 736 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the 737 * other type of cpumask_var_t implementation is configured. 738 * 739 * Please also note that __cpumask_var_read_mostly can be used to declare 740 * a cpumask_var_t variable itself (not its content) as read mostly. 741 */ 742 #ifdef CONFIG_CPUMASK_OFFSTACK 743 typedef struct cpumask *cpumask_var_t; 744 745 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x) 746 #define __cpumask_var_read_mostly __read_mostly 747 748 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); 749 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags); 750 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); 751 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags); 752 void alloc_bootmem_cpumask_var(cpumask_var_t *mask); 753 void free_cpumask_var(cpumask_var_t mask); 754 void free_bootmem_cpumask_var(cpumask_var_t mask); 755 756 static inline bool cpumask_available(cpumask_var_t mask) 757 { 758 return mask != NULL; 759 } 760 761 #else 762 typedef struct cpumask cpumask_var_t[1]; 763 764 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x) 765 #define __cpumask_var_read_mostly 766 767 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 768 { 769 return true; 770 } 771 772 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 773 int node) 774 { 775 return true; 776 } 777 778 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 779 { 780 cpumask_clear(*mask); 781 return true; 782 } 783 784 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 785 int node) 786 { 787 cpumask_clear(*mask); 788 return true; 789 } 790 791 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask) 792 { 793 } 794 795 static inline void free_cpumask_var(cpumask_var_t mask) 796 { 797 } 798 799 static inline void free_bootmem_cpumask_var(cpumask_var_t mask) 800 { 801 } 802 803 static inline bool cpumask_available(cpumask_var_t mask) 804 { 805 return true; 806 } 807 #endif /* CONFIG_CPUMASK_OFFSTACK */ 808 809 /* It's common to want to use cpu_all_mask in struct member initializers, 810 * so it has to refer to an address rather than a pointer. */ 811 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS); 812 #define cpu_all_mask to_cpumask(cpu_all_bits) 813 814 /* First bits of cpu_bit_bitmap are in fact unset. */ 815 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0]) 816 817 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask) 818 #define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask) 819 #define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask) 820 821 /* Wrappers for arch boot code to manipulate normally-constant masks */ 822 void init_cpu_present(const struct cpumask *src); 823 void init_cpu_possible(const struct cpumask *src); 824 void init_cpu_online(const struct cpumask *src); 825 826 static inline void reset_cpu_possible_mask(void) 827 { 828 bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS); 829 } 830 831 static inline void 832 set_cpu_possible(unsigned int cpu, bool possible) 833 { 834 if (possible) 835 cpumask_set_cpu(cpu, &__cpu_possible_mask); 836 else 837 cpumask_clear_cpu(cpu, &__cpu_possible_mask); 838 } 839 840 static inline void 841 set_cpu_present(unsigned int cpu, bool present) 842 { 843 if (present) 844 cpumask_set_cpu(cpu, &__cpu_present_mask); 845 else 846 cpumask_clear_cpu(cpu, &__cpu_present_mask); 847 } 848 849 void set_cpu_online(unsigned int cpu, bool online); 850 851 static inline void 852 set_cpu_active(unsigned int cpu, bool active) 853 { 854 if (active) 855 cpumask_set_cpu(cpu, &__cpu_active_mask); 856 else 857 cpumask_clear_cpu(cpu, &__cpu_active_mask); 858 } 859 860 861 /** 862 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask * 863 * @bitmap: the bitmap 864 * 865 * There are a few places where cpumask_var_t isn't appropriate and 866 * static cpumasks must be used (eg. very early boot), yet we don't 867 * expose the definition of 'struct cpumask'. 868 * 869 * This does the conversion, and can be used as a constant initializer. 870 */ 871 #define to_cpumask(bitmap) \ 872 ((struct cpumask *)(1 ? (bitmap) \ 873 : (void *)sizeof(__check_is_bitmap(bitmap)))) 874 875 static inline int __check_is_bitmap(const unsigned long *bitmap) 876 { 877 return 1; 878 } 879 880 /* 881 * Special-case data structure for "single bit set only" constant CPU masks. 882 * 883 * We pre-generate all the 64 (or 32) possible bit positions, with enough 884 * padding to the left and the right, and return the constant pointer 885 * appropriately offset. 886 */ 887 extern const unsigned long 888 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)]; 889 890 static inline const struct cpumask *get_cpu_mask(unsigned int cpu) 891 { 892 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; 893 p -= cpu / BITS_PER_LONG; 894 return to_cpumask(p); 895 } 896 897 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu)) 898 899 #if NR_CPUS <= BITS_PER_LONG 900 #define CPU_BITS_ALL \ 901 { \ 902 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 903 } 904 905 #else /* NR_CPUS > BITS_PER_LONG */ 906 907 #define CPU_BITS_ALL \ 908 { \ 909 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 910 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 911 } 912 #endif /* NR_CPUS > BITS_PER_LONG */ 913 914 /** 915 * cpumap_print_to_pagebuf - copies the cpumask into the buffer either 916 * as comma-separated list of cpus or hex values of cpumask 917 * @list: indicates whether the cpumap must be list 918 * @mask: the cpumask to copy 919 * @buf: the buffer to copy into 920 * 921 * Returns the length of the (null-terminated) @buf string, zero if 922 * nothing is copied. 923 */ 924 static inline ssize_t 925 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask) 926 { 927 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask), 928 nr_cpu_ids); 929 } 930 931 #if NR_CPUS <= BITS_PER_LONG 932 #define CPU_MASK_ALL \ 933 (cpumask_t) { { \ 934 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 935 } } 936 #else 937 #define CPU_MASK_ALL \ 938 (cpumask_t) { { \ 939 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 940 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 941 } } 942 #endif /* NR_CPUS > BITS_PER_LONG */ 943 944 #define CPU_MASK_NONE \ 945 (cpumask_t) { { \ 946 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 947 } } 948 949 #define CPU_MASK_CPU0 \ 950 (cpumask_t) { { \ 951 [0] = 1UL \ 952 } } 953 954 #endif /* __LINUX_CPUMASK_H */ 955