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 extern struct cpumask __cpu_dying_mask; 95 #define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask) 96 #define cpu_online_mask ((const struct cpumask *)&__cpu_online_mask) 97 #define cpu_present_mask ((const struct cpumask *)&__cpu_present_mask) 98 #define cpu_active_mask ((const struct cpumask *)&__cpu_active_mask) 99 #define cpu_dying_mask ((const struct cpumask *)&__cpu_dying_mask) 100 101 extern atomic_t __num_online_cpus; 102 103 extern cpumask_t cpus_booted_once_mask; 104 105 static inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits) 106 { 107 #ifdef CONFIG_DEBUG_PER_CPU_MAPS 108 WARN_ON_ONCE(cpu >= bits); 109 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */ 110 } 111 112 /* verify cpu argument to cpumask_* operators */ 113 static inline unsigned int cpumask_check(unsigned int cpu) 114 { 115 cpu_max_bits_warn(cpu, nr_cpumask_bits); 116 return cpu; 117 } 118 119 #if NR_CPUS == 1 120 /* Uniprocessor. Assume all masks are "1". */ 121 static inline unsigned int cpumask_first(const struct cpumask *srcp) 122 { 123 return 0; 124 } 125 126 static inline unsigned int cpumask_first_zero(const struct cpumask *srcp) 127 { 128 return 0; 129 } 130 131 static inline unsigned int cpumask_first_and(const struct cpumask *srcp1, 132 const struct cpumask *srcp2) 133 { 134 return 0; 135 } 136 137 static inline unsigned int cpumask_last(const struct cpumask *srcp) 138 { 139 return 0; 140 } 141 142 /* Valid inputs for n are -1 and 0. */ 143 static inline unsigned int cpumask_next(int n, const struct cpumask *srcp) 144 { 145 return n+1; 146 } 147 148 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) 149 { 150 return n+1; 151 } 152 153 static inline unsigned int cpumask_next_and(int n, 154 const struct cpumask *srcp, 155 const struct cpumask *andp) 156 { 157 return n+1; 158 } 159 160 static inline unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, 161 int start, bool wrap) 162 { 163 /* cpu0 unless stop condition, wrap and at cpu0, then nr_cpumask_bits */ 164 return (wrap && n == 0); 165 } 166 167 /* cpu must be a valid cpu, ie 0, so there's no other choice. */ 168 static inline unsigned int cpumask_any_but(const struct cpumask *mask, 169 unsigned int cpu) 170 { 171 return 1; 172 } 173 174 static inline unsigned int cpumask_local_spread(unsigned int i, int node) 175 { 176 return 0; 177 } 178 179 static inline int cpumask_any_and_distribute(const struct cpumask *src1p, 180 const struct cpumask *src2p) { 181 return cpumask_first_and(src1p, src2p); 182 } 183 184 static inline int cpumask_any_distribute(const struct cpumask *srcp) 185 { 186 return cpumask_first(srcp); 187 } 188 189 #define for_each_cpu(cpu, mask) \ 190 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) 191 #define for_each_cpu_not(cpu, mask) \ 192 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) 193 #define for_each_cpu_wrap(cpu, mask, start) \ 194 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)(start)) 195 #define for_each_cpu_and(cpu, mask1, mask2) \ 196 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask1, (void)mask2) 197 #else 198 /** 199 * cpumask_first - get the first cpu in a cpumask 200 * @srcp: the cpumask pointer 201 * 202 * Returns >= nr_cpu_ids if no cpus set. 203 */ 204 static inline unsigned int cpumask_first(const struct cpumask *srcp) 205 { 206 return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits); 207 } 208 209 /** 210 * cpumask_first_zero - get the first unset cpu in a cpumask 211 * @srcp: the cpumask pointer 212 * 213 * Returns >= nr_cpu_ids if all cpus are set. 214 */ 215 static inline unsigned int cpumask_first_zero(const struct cpumask *srcp) 216 { 217 return find_first_zero_bit(cpumask_bits(srcp), nr_cpumask_bits); 218 } 219 220 /** 221 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2 222 * @src1p: the first input 223 * @src2p: the second input 224 * 225 * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and(). 226 */ 227 static inline 228 unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2) 229 { 230 return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), nr_cpumask_bits); 231 } 232 233 /** 234 * cpumask_last - get the last CPU in a cpumask 235 * @srcp: - the cpumask pointer 236 * 237 * Returns >= nr_cpumask_bits if no CPUs set. 238 */ 239 static inline unsigned int cpumask_last(const struct cpumask *srcp) 240 { 241 return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits); 242 } 243 244 unsigned int __pure cpumask_next(int n, const struct cpumask *srcp); 245 246 /** 247 * cpumask_next_zero - get the next unset cpu in a cpumask 248 * @n: the cpu prior to the place to search (ie. return will be > @n) 249 * @srcp: the cpumask pointer 250 * 251 * Returns >= nr_cpu_ids if no further cpus unset. 252 */ 253 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) 254 { 255 /* -1 is a legal arg here. */ 256 if (n != -1) 257 cpumask_check(n); 258 return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1); 259 } 260 261 int __pure cpumask_next_and(int n, const struct cpumask *, const struct cpumask *); 262 int __pure cpumask_any_but(const struct cpumask *mask, unsigned int cpu); 263 unsigned int cpumask_local_spread(unsigned int i, int node); 264 int cpumask_any_and_distribute(const struct cpumask *src1p, 265 const struct cpumask *src2p); 266 int cpumask_any_distribute(const struct cpumask *srcp); 267 268 /** 269 * for_each_cpu - iterate over every cpu in a mask 270 * @cpu: the (optionally unsigned) integer iterator 271 * @mask: the cpumask pointer 272 * 273 * After the loop, cpu is >= nr_cpu_ids. 274 */ 275 #define for_each_cpu(cpu, mask) \ 276 for ((cpu) = -1; \ 277 (cpu) = cpumask_next((cpu), (mask)), \ 278 (cpu) < nr_cpu_ids;) 279 280 /** 281 * for_each_cpu_not - iterate over every cpu in a complemented mask 282 * @cpu: the (optionally unsigned) integer iterator 283 * @mask: the cpumask pointer 284 * 285 * After the loop, cpu is >= nr_cpu_ids. 286 */ 287 #define for_each_cpu_not(cpu, mask) \ 288 for ((cpu) = -1; \ 289 (cpu) = cpumask_next_zero((cpu), (mask)), \ 290 (cpu) < nr_cpu_ids;) 291 292 extern int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap); 293 294 /** 295 * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location 296 * @cpu: the (optionally unsigned) integer iterator 297 * @mask: the cpumask pointer 298 * @start: the start location 299 * 300 * The implementation does not assume any bit in @mask is set (including @start). 301 * 302 * After the loop, cpu is >= nr_cpu_ids. 303 */ 304 #define for_each_cpu_wrap(cpu, mask, start) \ 305 for ((cpu) = cpumask_next_wrap((start)-1, (mask), (start), false); \ 306 (cpu) < nr_cpumask_bits; \ 307 (cpu) = cpumask_next_wrap((cpu), (mask), (start), true)) 308 309 /** 310 * for_each_cpu_and - iterate over every cpu in both masks 311 * @cpu: the (optionally unsigned) integer iterator 312 * @mask1: the first cpumask pointer 313 * @mask2: the second cpumask pointer 314 * 315 * This saves a temporary CPU mask in many places. It is equivalent to: 316 * struct cpumask tmp; 317 * cpumask_and(&tmp, &mask1, &mask2); 318 * for_each_cpu(cpu, &tmp) 319 * ... 320 * 321 * After the loop, cpu is >= nr_cpu_ids. 322 */ 323 #define for_each_cpu_and(cpu, mask1, mask2) \ 324 for ((cpu) = -1; \ 325 (cpu) = cpumask_next_and((cpu), (mask1), (mask2)), \ 326 (cpu) < nr_cpu_ids;) 327 #endif /* SMP */ 328 329 #define CPU_BITS_NONE \ 330 { \ 331 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 332 } 333 334 #define CPU_BITS_CPU0 \ 335 { \ 336 [0] = 1UL \ 337 } 338 339 /** 340 * cpumask_set_cpu - set a cpu in a cpumask 341 * @cpu: cpu number (< nr_cpu_ids) 342 * @dstp: the cpumask pointer 343 */ 344 static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 345 { 346 set_bit(cpumask_check(cpu), cpumask_bits(dstp)); 347 } 348 349 static inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 350 { 351 __set_bit(cpumask_check(cpu), cpumask_bits(dstp)); 352 } 353 354 355 /** 356 * cpumask_clear_cpu - clear a cpu in a cpumask 357 * @cpu: cpu number (< nr_cpu_ids) 358 * @dstp: the cpumask pointer 359 */ 360 static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp) 361 { 362 clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); 363 } 364 365 static inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp) 366 { 367 __clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); 368 } 369 370 /** 371 * cpumask_test_cpu - test for a cpu in a cpumask 372 * @cpu: cpu number (< nr_cpu_ids) 373 * @cpumask: the cpumask pointer 374 * 375 * Returns 1 if @cpu is set in @cpumask, else returns 0 376 */ 377 static inline int cpumask_test_cpu(int cpu, const struct cpumask *cpumask) 378 { 379 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask))); 380 } 381 382 /** 383 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask 384 * @cpu: cpu number (< nr_cpu_ids) 385 * @cpumask: the cpumask pointer 386 * 387 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0 388 * 389 * test_and_set_bit wrapper for cpumasks. 390 */ 391 static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask) 392 { 393 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 394 } 395 396 /** 397 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask 398 * @cpu: cpu number (< nr_cpu_ids) 399 * @cpumask: the cpumask pointer 400 * 401 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0 402 * 403 * test_and_clear_bit wrapper for cpumasks. 404 */ 405 static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask) 406 { 407 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 408 } 409 410 /** 411 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask 412 * @dstp: the cpumask pointer 413 */ 414 static inline void cpumask_setall(struct cpumask *dstp) 415 { 416 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits); 417 } 418 419 /** 420 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask 421 * @dstp: the cpumask pointer 422 */ 423 static inline void cpumask_clear(struct cpumask *dstp) 424 { 425 bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits); 426 } 427 428 /** 429 * cpumask_and - *dstp = *src1p & *src2p 430 * @dstp: the cpumask result 431 * @src1p: the first input 432 * @src2p: the second input 433 * 434 * If *@dstp is empty, returns 0, else returns 1 435 */ 436 static inline int cpumask_and(struct cpumask *dstp, 437 const struct cpumask *src1p, 438 const struct cpumask *src2p) 439 { 440 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p), 441 cpumask_bits(src2p), nr_cpumask_bits); 442 } 443 444 /** 445 * cpumask_or - *dstp = *src1p | *src2p 446 * @dstp: the cpumask result 447 * @src1p: the first input 448 * @src2p: the second input 449 */ 450 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p, 451 const struct cpumask *src2p) 452 { 453 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p), 454 cpumask_bits(src2p), nr_cpumask_bits); 455 } 456 457 /** 458 * cpumask_xor - *dstp = *src1p ^ *src2p 459 * @dstp: the cpumask result 460 * @src1p: the first input 461 * @src2p: the second input 462 */ 463 static inline void cpumask_xor(struct cpumask *dstp, 464 const struct cpumask *src1p, 465 const struct cpumask *src2p) 466 { 467 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p), 468 cpumask_bits(src2p), nr_cpumask_bits); 469 } 470 471 /** 472 * cpumask_andnot - *dstp = *src1p & ~*src2p 473 * @dstp: the cpumask result 474 * @src1p: the first input 475 * @src2p: the second input 476 * 477 * If *@dstp is empty, returns 0, else returns 1 478 */ 479 static inline int cpumask_andnot(struct cpumask *dstp, 480 const struct cpumask *src1p, 481 const struct cpumask *src2p) 482 { 483 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p), 484 cpumask_bits(src2p), nr_cpumask_bits); 485 } 486 487 /** 488 * cpumask_complement - *dstp = ~*srcp 489 * @dstp: the cpumask result 490 * @srcp: the input to invert 491 */ 492 static inline void cpumask_complement(struct cpumask *dstp, 493 const struct cpumask *srcp) 494 { 495 bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp), 496 nr_cpumask_bits); 497 } 498 499 /** 500 * cpumask_equal - *src1p == *src2p 501 * @src1p: the first input 502 * @src2p: the second input 503 */ 504 static inline bool cpumask_equal(const struct cpumask *src1p, 505 const struct cpumask *src2p) 506 { 507 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p), 508 nr_cpumask_bits); 509 } 510 511 /** 512 * cpumask_or_equal - *src1p | *src2p == *src3p 513 * @src1p: the first input 514 * @src2p: the second input 515 * @src3p: the third input 516 */ 517 static inline bool cpumask_or_equal(const struct cpumask *src1p, 518 const struct cpumask *src2p, 519 const struct cpumask *src3p) 520 { 521 return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p), 522 cpumask_bits(src3p), nr_cpumask_bits); 523 } 524 525 /** 526 * cpumask_intersects - (*src1p & *src2p) != 0 527 * @src1p: the first input 528 * @src2p: the second input 529 */ 530 static inline bool cpumask_intersects(const struct cpumask *src1p, 531 const struct cpumask *src2p) 532 { 533 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p), 534 nr_cpumask_bits); 535 } 536 537 /** 538 * cpumask_subset - (*src1p & ~*src2p) == 0 539 * @src1p: the first input 540 * @src2p: the second input 541 * 542 * Returns 1 if *@src1p is a subset of *@src2p, else returns 0 543 */ 544 static inline int cpumask_subset(const struct cpumask *src1p, 545 const struct cpumask *src2p) 546 { 547 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p), 548 nr_cpumask_bits); 549 } 550 551 /** 552 * cpumask_empty - *srcp == 0 553 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear. 554 */ 555 static inline bool cpumask_empty(const struct cpumask *srcp) 556 { 557 return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits); 558 } 559 560 /** 561 * cpumask_full - *srcp == 0xFFFFFFFF... 562 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set. 563 */ 564 static inline bool cpumask_full(const struct cpumask *srcp) 565 { 566 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits); 567 } 568 569 /** 570 * cpumask_weight - Count of bits in *srcp 571 * @srcp: the cpumask to count bits (< nr_cpu_ids) in. 572 */ 573 static inline unsigned int cpumask_weight(const struct cpumask *srcp) 574 { 575 return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits); 576 } 577 578 /** 579 * cpumask_shift_right - *dstp = *srcp >> n 580 * @dstp: the cpumask result 581 * @srcp: the input to shift 582 * @n: the number of bits to shift by 583 */ 584 static inline void cpumask_shift_right(struct cpumask *dstp, 585 const struct cpumask *srcp, int n) 586 { 587 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n, 588 nr_cpumask_bits); 589 } 590 591 /** 592 * cpumask_shift_left - *dstp = *srcp << n 593 * @dstp: the cpumask result 594 * @srcp: the input to shift 595 * @n: the number of bits to shift by 596 */ 597 static inline void cpumask_shift_left(struct cpumask *dstp, 598 const struct cpumask *srcp, int n) 599 { 600 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n, 601 nr_cpumask_bits); 602 } 603 604 /** 605 * cpumask_copy - *dstp = *srcp 606 * @dstp: the result 607 * @srcp: the input cpumask 608 */ 609 static inline void cpumask_copy(struct cpumask *dstp, 610 const struct cpumask *srcp) 611 { 612 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits); 613 } 614 615 /** 616 * cpumask_any - pick a "random" cpu from *srcp 617 * @srcp: the input cpumask 618 * 619 * Returns >= nr_cpu_ids if no cpus set. 620 */ 621 #define cpumask_any(srcp) cpumask_first(srcp) 622 623 /** 624 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2 625 * @mask1: the first input cpumask 626 * @mask2: the second input cpumask 627 * 628 * Returns >= nr_cpu_ids if no cpus set. 629 */ 630 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2)) 631 632 /** 633 * cpumask_of - the cpumask containing just a given cpu 634 * @cpu: the cpu (<= nr_cpu_ids) 635 */ 636 #define cpumask_of(cpu) (get_cpu_mask(cpu)) 637 638 /** 639 * cpumask_parse_user - extract a cpumask from a user string 640 * @buf: the buffer to extract from 641 * @len: the length of the buffer 642 * @dstp: the cpumask to set. 643 * 644 * Returns -errno, or 0 for success. 645 */ 646 static inline int cpumask_parse_user(const char __user *buf, int len, 647 struct cpumask *dstp) 648 { 649 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits); 650 } 651 652 /** 653 * cpumask_parselist_user - extract a cpumask from a user string 654 * @buf: the buffer to extract from 655 * @len: the length of the buffer 656 * @dstp: the cpumask to set. 657 * 658 * Returns -errno, or 0 for success. 659 */ 660 static inline int cpumask_parselist_user(const char __user *buf, int len, 661 struct cpumask *dstp) 662 { 663 return bitmap_parselist_user(buf, len, cpumask_bits(dstp), 664 nr_cpumask_bits); 665 } 666 667 /** 668 * cpumask_parse - extract a cpumask from a string 669 * @buf: the buffer to extract from 670 * @dstp: the cpumask to set. 671 * 672 * Returns -errno, or 0 for success. 673 */ 674 static inline int cpumask_parse(const char *buf, struct cpumask *dstp) 675 { 676 return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits); 677 } 678 679 /** 680 * cpulist_parse - extract a cpumask from a user string of ranges 681 * @buf: the buffer to extract from 682 * @dstp: the cpumask to set. 683 * 684 * Returns -errno, or 0 for success. 685 */ 686 static inline int cpulist_parse(const char *buf, struct cpumask *dstp) 687 { 688 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits); 689 } 690 691 /** 692 * cpumask_size - size to allocate for a 'struct cpumask' in bytes 693 */ 694 static inline unsigned int cpumask_size(void) 695 { 696 return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long); 697 } 698 699 /* 700 * cpumask_var_t: struct cpumask for stack usage. 701 * 702 * Oh, the wicked games we play! In order to make kernel coding a 703 * little more difficult, we typedef cpumask_var_t to an array or a 704 * pointer: doing &mask on an array is a noop, so it still works. 705 * 706 * ie. 707 * cpumask_var_t tmpmask; 708 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 709 * return -ENOMEM; 710 * 711 * ... use 'tmpmask' like a normal struct cpumask * ... 712 * 713 * free_cpumask_var(tmpmask); 714 * 715 * 716 * However, one notable exception is there. alloc_cpumask_var() allocates 717 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has 718 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t. 719 * 720 * cpumask_var_t tmpmask; 721 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 722 * return -ENOMEM; 723 * 724 * var = *tmpmask; 725 * 726 * This code makes NR_CPUS length memcopy and brings to a memory corruption. 727 * cpumask_copy() provide safe copy functionality. 728 * 729 * Note that there is another evil here: If you define a cpumask_var_t 730 * as a percpu variable then the way to obtain the address of the cpumask 731 * structure differently influences what this_cpu_* operation needs to be 732 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use 733 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the 734 * other type of cpumask_var_t implementation is configured. 735 * 736 * Please also note that __cpumask_var_read_mostly can be used to declare 737 * a cpumask_var_t variable itself (not its content) as read mostly. 738 */ 739 #ifdef CONFIG_CPUMASK_OFFSTACK 740 typedef struct cpumask *cpumask_var_t; 741 742 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x) 743 #define __cpumask_var_read_mostly __read_mostly 744 745 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); 746 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags); 747 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); 748 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags); 749 void alloc_bootmem_cpumask_var(cpumask_var_t *mask); 750 void free_cpumask_var(cpumask_var_t mask); 751 void free_bootmem_cpumask_var(cpumask_var_t mask); 752 753 static inline bool cpumask_available(cpumask_var_t mask) 754 { 755 return mask != NULL; 756 } 757 758 #else 759 typedef struct cpumask cpumask_var_t[1]; 760 761 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x) 762 #define __cpumask_var_read_mostly 763 764 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 765 { 766 return true; 767 } 768 769 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 770 int node) 771 { 772 return true; 773 } 774 775 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 776 { 777 cpumask_clear(*mask); 778 return true; 779 } 780 781 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 782 int node) 783 { 784 cpumask_clear(*mask); 785 return true; 786 } 787 788 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask) 789 { 790 } 791 792 static inline void free_cpumask_var(cpumask_var_t mask) 793 { 794 } 795 796 static inline void free_bootmem_cpumask_var(cpumask_var_t mask) 797 { 798 } 799 800 static inline bool cpumask_available(cpumask_var_t mask) 801 { 802 return true; 803 } 804 #endif /* CONFIG_CPUMASK_OFFSTACK */ 805 806 /* It's common to want to use cpu_all_mask in struct member initializers, 807 * so it has to refer to an address rather than a pointer. */ 808 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS); 809 #define cpu_all_mask to_cpumask(cpu_all_bits) 810 811 /* First bits of cpu_bit_bitmap are in fact unset. */ 812 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0]) 813 814 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask) 815 #define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask) 816 #define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask) 817 818 /* Wrappers for arch boot code to manipulate normally-constant masks */ 819 void init_cpu_present(const struct cpumask *src); 820 void init_cpu_possible(const struct cpumask *src); 821 void init_cpu_online(const struct cpumask *src); 822 823 static inline void reset_cpu_possible_mask(void) 824 { 825 bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS); 826 } 827 828 static inline void 829 set_cpu_possible(unsigned int cpu, bool possible) 830 { 831 if (possible) 832 cpumask_set_cpu(cpu, &__cpu_possible_mask); 833 else 834 cpumask_clear_cpu(cpu, &__cpu_possible_mask); 835 } 836 837 static inline void 838 set_cpu_present(unsigned int cpu, bool present) 839 { 840 if (present) 841 cpumask_set_cpu(cpu, &__cpu_present_mask); 842 else 843 cpumask_clear_cpu(cpu, &__cpu_present_mask); 844 } 845 846 void set_cpu_online(unsigned int cpu, bool online); 847 848 static inline void 849 set_cpu_active(unsigned int cpu, bool active) 850 { 851 if (active) 852 cpumask_set_cpu(cpu, &__cpu_active_mask); 853 else 854 cpumask_clear_cpu(cpu, &__cpu_active_mask); 855 } 856 857 static inline void 858 set_cpu_dying(unsigned int cpu, bool dying) 859 { 860 if (dying) 861 cpumask_set_cpu(cpu, &__cpu_dying_mask); 862 else 863 cpumask_clear_cpu(cpu, &__cpu_dying_mask); 864 } 865 866 /** 867 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask * 868 * @bitmap: the bitmap 869 * 870 * There are a few places where cpumask_var_t isn't appropriate and 871 * static cpumasks must be used (eg. very early boot), yet we don't 872 * expose the definition of 'struct cpumask'. 873 * 874 * This does the conversion, and can be used as a constant initializer. 875 */ 876 #define to_cpumask(bitmap) \ 877 ((struct cpumask *)(1 ? (bitmap) \ 878 : (void *)sizeof(__check_is_bitmap(bitmap)))) 879 880 static inline int __check_is_bitmap(const unsigned long *bitmap) 881 { 882 return 1; 883 } 884 885 /* 886 * Special-case data structure for "single bit set only" constant CPU masks. 887 * 888 * We pre-generate all the 64 (or 32) possible bit positions, with enough 889 * padding to the left and the right, and return the constant pointer 890 * appropriately offset. 891 */ 892 extern const unsigned long 893 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)]; 894 895 static inline const struct cpumask *get_cpu_mask(unsigned int cpu) 896 { 897 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; 898 p -= cpu / BITS_PER_LONG; 899 return to_cpumask(p); 900 } 901 902 #if NR_CPUS > 1 903 /** 904 * num_online_cpus() - Read the number of online CPUs 905 * 906 * Despite the fact that __num_online_cpus is of type atomic_t, this 907 * interface gives only a momentary snapshot and is not protected against 908 * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held 909 * region. 910 */ 911 static inline unsigned int num_online_cpus(void) 912 { 913 return atomic_read(&__num_online_cpus); 914 } 915 #define num_possible_cpus() cpumask_weight(cpu_possible_mask) 916 #define num_present_cpus() cpumask_weight(cpu_present_mask) 917 #define num_active_cpus() cpumask_weight(cpu_active_mask) 918 919 static inline bool cpu_online(unsigned int cpu) 920 { 921 return cpumask_test_cpu(cpu, cpu_online_mask); 922 } 923 924 static inline bool cpu_possible(unsigned int cpu) 925 { 926 return cpumask_test_cpu(cpu, cpu_possible_mask); 927 } 928 929 static inline bool cpu_present(unsigned int cpu) 930 { 931 return cpumask_test_cpu(cpu, cpu_present_mask); 932 } 933 934 static inline bool cpu_active(unsigned int cpu) 935 { 936 return cpumask_test_cpu(cpu, cpu_active_mask); 937 } 938 939 static inline bool cpu_dying(unsigned int cpu) 940 { 941 return cpumask_test_cpu(cpu, cpu_dying_mask); 942 } 943 944 #else 945 946 #define num_online_cpus() 1U 947 #define num_possible_cpus() 1U 948 #define num_present_cpus() 1U 949 #define num_active_cpus() 1U 950 951 static inline bool cpu_online(unsigned int cpu) 952 { 953 return cpu == 0; 954 } 955 956 static inline bool cpu_possible(unsigned int cpu) 957 { 958 return cpu == 0; 959 } 960 961 static inline bool cpu_present(unsigned int cpu) 962 { 963 return cpu == 0; 964 } 965 966 static inline bool cpu_active(unsigned int cpu) 967 { 968 return cpu == 0; 969 } 970 971 static inline bool cpu_dying(unsigned int cpu) 972 { 973 return false; 974 } 975 976 #endif /* NR_CPUS > 1 */ 977 978 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu)) 979 980 #if NR_CPUS <= BITS_PER_LONG 981 #define CPU_BITS_ALL \ 982 { \ 983 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 984 } 985 986 #else /* NR_CPUS > BITS_PER_LONG */ 987 988 #define CPU_BITS_ALL \ 989 { \ 990 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 991 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 992 } 993 #endif /* NR_CPUS > BITS_PER_LONG */ 994 995 /** 996 * cpumap_print_to_pagebuf - copies the cpumask into the buffer either 997 * as comma-separated list of cpus or hex values of cpumask 998 * @list: indicates whether the cpumap must be list 999 * @mask: the cpumask to copy 1000 * @buf: the buffer to copy into 1001 * 1002 * Returns the length of the (null-terminated) @buf string, zero if 1003 * nothing is copied. 1004 */ 1005 static inline ssize_t 1006 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask) 1007 { 1008 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask), 1009 nr_cpu_ids); 1010 } 1011 1012 /** 1013 * cpumap_print_bitmask_to_buf - copies the cpumask into the buffer as 1014 * hex values of cpumask 1015 * 1016 * @buf: the buffer to copy into 1017 * @mask: the cpumask to copy 1018 * @off: in the string from which we are copying, we copy to @buf 1019 * @count: the maximum number of bytes to print 1020 * 1021 * The function prints the cpumask into the buffer as hex values of 1022 * cpumask; Typically used by bin_attribute to export cpumask bitmask 1023 * ABI. 1024 * 1025 * Returns the length of how many bytes have been copied, excluding 1026 * terminating '\0'. 1027 */ 1028 static inline ssize_t 1029 cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask, 1030 loff_t off, size_t count) 1031 { 1032 return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask), 1033 nr_cpu_ids, off, count) - 1; 1034 } 1035 1036 /** 1037 * cpumap_print_list_to_buf - copies the cpumask into the buffer as 1038 * comma-separated list of cpus 1039 * 1040 * Everything is same with the above cpumap_print_bitmask_to_buf() 1041 * except the print format. 1042 */ 1043 static inline ssize_t 1044 cpumap_print_list_to_buf(char *buf, const struct cpumask *mask, 1045 loff_t off, size_t count) 1046 { 1047 return bitmap_print_list_to_buf(buf, cpumask_bits(mask), 1048 nr_cpu_ids, off, count) - 1; 1049 } 1050 1051 #if NR_CPUS <= BITS_PER_LONG 1052 #define CPU_MASK_ALL \ 1053 (cpumask_t) { { \ 1054 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 1055 } } 1056 #else 1057 #define CPU_MASK_ALL \ 1058 (cpumask_t) { { \ 1059 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 1060 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 1061 } } 1062 #endif /* NR_CPUS > BITS_PER_LONG */ 1063 1064 #define CPU_MASK_NONE \ 1065 (cpumask_t) { { \ 1066 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 1067 } } 1068 1069 #define CPU_MASK_CPU0 \ 1070 (cpumask_t) { { \ 1071 [0] = 1UL \ 1072 } } 1073 1074 #endif /* __LINUX_CPUMASK_H */ 1075