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 #include <linux/gfp_types.h> 16 #include <linux/numa.h> 17 18 /* Don't assign or return these: may not be this big! */ 19 typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t; 20 21 /** 22 * cpumask_bits - get the bits in a cpumask 23 * @maskp: the struct cpumask * 24 * 25 * You should only assume nr_cpu_ids bits of this mask are valid. This is 26 * a macro so it's const-correct. 27 */ 28 #define cpumask_bits(maskp) ((maskp)->bits) 29 30 /** 31 * cpumask_pr_args - printf args to output a cpumask 32 * @maskp: cpumask to be printed 33 * 34 * Can be used to provide arguments for '%*pb[l]' when printing a cpumask. 35 */ 36 #define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp) 37 38 #if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS) 39 #define nr_cpu_ids ((unsigned int)NR_CPUS) 40 #else 41 extern unsigned int nr_cpu_ids; 42 #endif 43 44 static inline void set_nr_cpu_ids(unsigned int nr) 45 { 46 #if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS) 47 WARN_ON(nr != nr_cpu_ids); 48 #else 49 nr_cpu_ids = nr; 50 #endif 51 } 52 53 /* Deprecated. Always use nr_cpu_ids. */ 54 #define nr_cpumask_bits nr_cpu_ids 55 56 /* 57 * The following particular system cpumasks and operations manage 58 * possible, present, active and online cpus. 59 * 60 * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable 61 * cpu_present_mask - has bit 'cpu' set iff cpu is populated 62 * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler 63 * cpu_active_mask - has bit 'cpu' set iff cpu available to migration 64 * 65 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online. 66 * 67 * The cpu_possible_mask is fixed at boot time, as the set of CPU id's 68 * that it is possible might ever be plugged in at anytime during the 69 * life of that system boot. The cpu_present_mask is dynamic(*), 70 * representing which CPUs are currently plugged in. And 71 * cpu_online_mask is the dynamic subset of cpu_present_mask, 72 * indicating those CPUs available for scheduling. 73 * 74 * If HOTPLUG is enabled, then cpu_present_mask varies dynamically, 75 * depending on what ACPI reports as currently plugged in, otherwise 76 * cpu_present_mask is just a copy of cpu_possible_mask. 77 * 78 * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not 79 * hotplug, it's a copy of cpu_possible_mask, hence fixed at boot. 80 * 81 * Subtleties: 82 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode 83 * assumption that their single CPU is online. The UP 84 * cpu_{online,possible,present}_masks are placebos. Changing them 85 * will have no useful affect on the following num_*_cpus() 86 * and cpu_*() macros in the UP case. This ugliness is a UP 87 * optimization - don't waste any instructions or memory references 88 * asking if you're online or how many CPUs there are if there is 89 * only one CPU. 90 */ 91 92 extern struct cpumask __cpu_possible_mask; 93 extern struct cpumask __cpu_online_mask; 94 extern struct cpumask __cpu_present_mask; 95 extern struct cpumask __cpu_active_mask; 96 extern struct cpumask __cpu_dying_mask; 97 #define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask) 98 #define cpu_online_mask ((const struct cpumask *)&__cpu_online_mask) 99 #define cpu_present_mask ((const struct cpumask *)&__cpu_present_mask) 100 #define cpu_active_mask ((const struct cpumask *)&__cpu_active_mask) 101 #define cpu_dying_mask ((const struct cpumask *)&__cpu_dying_mask) 102 103 extern atomic_t __num_online_cpus; 104 105 extern cpumask_t cpus_booted_once_mask; 106 107 static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits) 108 { 109 #ifdef CONFIG_DEBUG_PER_CPU_MAPS 110 WARN_ON_ONCE(cpu >= bits); 111 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */ 112 } 113 114 /* verify cpu argument to cpumask_* operators */ 115 static __always_inline unsigned int cpumask_check(unsigned int cpu) 116 { 117 cpu_max_bits_warn(cpu, nr_cpumask_bits); 118 return cpu; 119 } 120 121 /** 122 * cpumask_first - get the first cpu in a cpumask 123 * @srcp: the cpumask pointer 124 * 125 * Returns >= nr_cpu_ids if no cpus set. 126 */ 127 static inline unsigned int cpumask_first(const struct cpumask *srcp) 128 { 129 return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits); 130 } 131 132 /** 133 * cpumask_first_zero - get the first unset cpu in a cpumask 134 * @srcp: the cpumask pointer 135 * 136 * Returns >= nr_cpu_ids if all cpus are set. 137 */ 138 static inline unsigned int cpumask_first_zero(const struct cpumask *srcp) 139 { 140 return find_first_zero_bit(cpumask_bits(srcp), nr_cpumask_bits); 141 } 142 143 /** 144 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2 145 * @src1p: the first input 146 * @src2p: the second input 147 * 148 * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and(). 149 */ 150 static inline 151 unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2) 152 { 153 return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), nr_cpumask_bits); 154 } 155 156 /** 157 * cpumask_last - get the last CPU in a cpumask 158 * @srcp: - the cpumask pointer 159 * 160 * Returns >= nr_cpumask_bits if no CPUs set. 161 */ 162 static inline unsigned int cpumask_last(const struct cpumask *srcp) 163 { 164 return find_last_bit(cpumask_bits(srcp), nr_cpumask_bits); 165 } 166 167 /** 168 * cpumask_next - get the next cpu in a cpumask 169 * @n: the cpu prior to the place to search (ie. return will be > @n) 170 * @srcp: the cpumask pointer 171 * 172 * Returns >= nr_cpu_ids if no further cpus set. 173 */ 174 static inline 175 unsigned int cpumask_next(int n, const struct cpumask *srcp) 176 { 177 /* -1 is a legal arg here. */ 178 if (n != -1) 179 cpumask_check(n); 180 return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1); 181 } 182 183 /** 184 * cpumask_next_zero - get the next unset cpu in a cpumask 185 * @n: the cpu prior to the place to search (ie. return will be > @n) 186 * @srcp: the cpumask pointer 187 * 188 * Returns >= nr_cpu_ids if no further cpus unset. 189 */ 190 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) 191 { 192 /* -1 is a legal arg here. */ 193 if (n != -1) 194 cpumask_check(n); 195 return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1); 196 } 197 198 #if NR_CPUS == 1 199 /* Uniprocessor: there is only one valid CPU */ 200 static inline unsigned int cpumask_local_spread(unsigned int i, int node) 201 { 202 return 0; 203 } 204 205 static inline unsigned int cpumask_any_and_distribute(const struct cpumask *src1p, 206 const struct cpumask *src2p) 207 { 208 return cpumask_first_and(src1p, src2p); 209 } 210 211 static inline unsigned int cpumask_any_distribute(const struct cpumask *srcp) 212 { 213 return cpumask_first(srcp); 214 } 215 #else 216 unsigned int cpumask_local_spread(unsigned int i, int node); 217 unsigned int cpumask_any_and_distribute(const struct cpumask *src1p, 218 const struct cpumask *src2p); 219 unsigned int cpumask_any_distribute(const struct cpumask *srcp); 220 #endif /* NR_CPUS */ 221 222 /** 223 * cpumask_next_and - get the next cpu in *src1p & *src2p 224 * @n: the cpu prior to the place to search (ie. return will be > @n) 225 * @src1p: the first cpumask pointer 226 * @src2p: the second cpumask pointer 227 * 228 * Returns >= nr_cpu_ids if no further cpus set in both. 229 */ 230 static inline 231 unsigned int cpumask_next_and(int n, const struct cpumask *src1p, 232 const struct cpumask *src2p) 233 { 234 /* -1 is a legal arg here. */ 235 if (n != -1) 236 cpumask_check(n); 237 return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p), 238 nr_cpumask_bits, n + 1); 239 } 240 241 /** 242 * for_each_cpu - iterate over every cpu in a mask 243 * @cpu: the (optionally unsigned) integer iterator 244 * @mask: the cpumask pointer 245 * 246 * After the loop, cpu is >= nr_cpu_ids. 247 */ 248 #define for_each_cpu(cpu, mask) \ 249 for_each_set_bit(cpu, cpumask_bits(mask), nr_cpumask_bits) 250 251 /** 252 * for_each_cpu_not - iterate over every cpu in a complemented mask 253 * @cpu: the (optionally unsigned) integer iterator 254 * @mask: the cpumask pointer 255 * 256 * After the loop, cpu is >= nr_cpu_ids. 257 */ 258 #define for_each_cpu_not(cpu, mask) \ 259 for_each_clear_bit(cpu, cpumask_bits(mask), nr_cpumask_bits) 260 261 #if NR_CPUS == 1 262 static inline 263 unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap) 264 { 265 cpumask_check(start); 266 if (n != -1) 267 cpumask_check(n); 268 269 /* 270 * Return the first available CPU when wrapping, or when starting before cpu0, 271 * since there is only one valid option. 272 */ 273 if (wrap && n >= 0) 274 return nr_cpumask_bits; 275 276 return cpumask_first(mask); 277 } 278 #else 279 unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap); 280 #endif 281 282 /** 283 * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location 284 * @cpu: the (optionally unsigned) integer iterator 285 * @mask: the cpumask pointer 286 * @start: the start location 287 * 288 * The implementation does not assume any bit in @mask is set (including @start). 289 * 290 * After the loop, cpu is >= nr_cpu_ids. 291 */ 292 #define for_each_cpu_wrap(cpu, mask, start) \ 293 for_each_set_bit_wrap(cpu, cpumask_bits(mask), nr_cpumask_bits, start) 294 295 /** 296 * for_each_cpu_and - iterate over every cpu in both masks 297 * @cpu: the (optionally unsigned) integer iterator 298 * @mask1: the first cpumask pointer 299 * @mask2: the second cpumask pointer 300 * 301 * This saves a temporary CPU mask in many places. It is equivalent to: 302 * struct cpumask tmp; 303 * cpumask_and(&tmp, &mask1, &mask2); 304 * for_each_cpu(cpu, &tmp) 305 * ... 306 * 307 * After the loop, cpu is >= nr_cpu_ids. 308 */ 309 #define for_each_cpu_and(cpu, mask1, mask2) \ 310 for_each_and_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), nr_cpumask_bits) 311 312 /** 313 * for_each_cpu_andnot - iterate over every cpu present in one mask, excluding 314 * those present in another. 315 * @cpu: the (optionally unsigned) integer iterator 316 * @mask1: the first cpumask pointer 317 * @mask2: the second cpumask pointer 318 * 319 * This saves a temporary CPU mask in many places. It is equivalent to: 320 * struct cpumask tmp; 321 * cpumask_andnot(&tmp, &mask1, &mask2); 322 * for_each_cpu(cpu, &tmp) 323 * ... 324 * 325 * After the loop, cpu is >= nr_cpu_ids. 326 */ 327 #define for_each_cpu_andnot(cpu, mask1, mask2) \ 328 for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), nr_cpumask_bits) 329 330 /** 331 * cpumask_any_but - return a "random" in a cpumask, but not this one. 332 * @mask: the cpumask to search 333 * @cpu: the cpu to ignore. 334 * 335 * Often used to find any cpu but smp_processor_id() in a mask. 336 * Returns >= nr_cpu_ids if no cpus set. 337 */ 338 static inline 339 unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu) 340 { 341 unsigned int i; 342 343 cpumask_check(cpu); 344 for_each_cpu(i, mask) 345 if (i != cpu) 346 break; 347 return i; 348 } 349 350 /** 351 * cpumask_nth - get the first cpu in a cpumask 352 * @srcp: the cpumask pointer 353 * @cpu: the N'th cpu to find, starting from 0 354 * 355 * Returns >= nr_cpu_ids if such cpu doesn't exist. 356 */ 357 static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp) 358 { 359 return find_nth_bit(cpumask_bits(srcp), nr_cpumask_bits, cpumask_check(cpu)); 360 } 361 362 /** 363 * cpumask_nth_and - get the first cpu in 2 cpumasks 364 * @srcp1: the cpumask pointer 365 * @srcp2: the cpumask pointer 366 * @cpu: the N'th cpu to find, starting from 0 367 * 368 * Returns >= nr_cpu_ids if such cpu doesn't exist. 369 */ 370 static inline 371 unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1, 372 const struct cpumask *srcp2) 373 { 374 return find_nth_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), 375 nr_cpumask_bits, cpumask_check(cpu)); 376 } 377 378 /** 379 * cpumask_nth_andnot - get the first cpu set in 1st cpumask, and clear in 2nd. 380 * @srcp1: the cpumask pointer 381 * @srcp2: the cpumask pointer 382 * @cpu: the N'th cpu to find, starting from 0 383 * 384 * Returns >= nr_cpu_ids if such cpu doesn't exist. 385 */ 386 static inline 387 unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1, 388 const struct cpumask *srcp2) 389 { 390 return find_nth_andnot_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), 391 nr_cpumask_bits, cpumask_check(cpu)); 392 } 393 394 /** 395 * cpumask_nth_and_andnot - get the Nth cpu set in 1st and 2nd cpumask, and clear in 3rd. 396 * @srcp1: the cpumask pointer 397 * @srcp2: the cpumask pointer 398 * @srcp3: the cpumask pointer 399 * @cpu: the N'th cpu to find, starting from 0 400 * 401 * Returns >= nr_cpu_ids if such cpu doesn't exist. 402 */ 403 static __always_inline 404 unsigned int cpumask_nth_and_andnot(unsigned int cpu, const struct cpumask *srcp1, 405 const struct cpumask *srcp2, 406 const struct cpumask *srcp3) 407 { 408 return find_nth_and_andnot_bit(cpumask_bits(srcp1), 409 cpumask_bits(srcp2), 410 cpumask_bits(srcp3), 411 nr_cpumask_bits, cpumask_check(cpu)); 412 } 413 414 #define CPU_BITS_NONE \ 415 { \ 416 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 417 } 418 419 #define CPU_BITS_CPU0 \ 420 { \ 421 [0] = 1UL \ 422 } 423 424 /** 425 * cpumask_set_cpu - set a cpu in a cpumask 426 * @cpu: cpu number (< nr_cpu_ids) 427 * @dstp: the cpumask pointer 428 */ 429 static __always_inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 430 { 431 set_bit(cpumask_check(cpu), cpumask_bits(dstp)); 432 } 433 434 static __always_inline void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 435 { 436 __set_bit(cpumask_check(cpu), cpumask_bits(dstp)); 437 } 438 439 440 /** 441 * cpumask_clear_cpu - clear a cpu in a cpumask 442 * @cpu: cpu number (< nr_cpu_ids) 443 * @dstp: the cpumask pointer 444 */ 445 static __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp) 446 { 447 clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); 448 } 449 450 static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp) 451 { 452 __clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); 453 } 454 455 /** 456 * cpumask_test_cpu - test for a cpu in a cpumask 457 * @cpu: cpu number (< nr_cpu_ids) 458 * @cpumask: the cpumask pointer 459 * 460 * Returns true if @cpu is set in @cpumask, else returns false 461 */ 462 static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask) 463 { 464 return test_bit(cpumask_check(cpu), cpumask_bits((cpumask))); 465 } 466 467 /** 468 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask 469 * @cpu: cpu number (< nr_cpu_ids) 470 * @cpumask: the cpumask pointer 471 * 472 * Returns true if @cpu is set in old bitmap of @cpumask, else returns false 473 * 474 * test_and_set_bit wrapper for cpumasks. 475 */ 476 static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask) 477 { 478 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 479 } 480 481 /** 482 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask 483 * @cpu: cpu number (< nr_cpu_ids) 484 * @cpumask: the cpumask pointer 485 * 486 * Returns true if @cpu is set in old bitmap of @cpumask, else returns false 487 * 488 * test_and_clear_bit wrapper for cpumasks. 489 */ 490 static __always_inline bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask) 491 { 492 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 493 } 494 495 /** 496 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask 497 * @dstp: the cpumask pointer 498 */ 499 static inline void cpumask_setall(struct cpumask *dstp) 500 { 501 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits); 502 } 503 504 /** 505 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask 506 * @dstp: the cpumask pointer 507 */ 508 static inline void cpumask_clear(struct cpumask *dstp) 509 { 510 bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits); 511 } 512 513 /** 514 * cpumask_and - *dstp = *src1p & *src2p 515 * @dstp: the cpumask result 516 * @src1p: the first input 517 * @src2p: the second input 518 * 519 * If *@dstp is empty, returns false, else returns true 520 */ 521 static inline bool cpumask_and(struct cpumask *dstp, 522 const struct cpumask *src1p, 523 const struct cpumask *src2p) 524 { 525 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p), 526 cpumask_bits(src2p), nr_cpumask_bits); 527 } 528 529 /** 530 * cpumask_or - *dstp = *src1p | *src2p 531 * @dstp: the cpumask result 532 * @src1p: the first input 533 * @src2p: the second input 534 */ 535 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p, 536 const struct cpumask *src2p) 537 { 538 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p), 539 cpumask_bits(src2p), nr_cpumask_bits); 540 } 541 542 /** 543 * cpumask_xor - *dstp = *src1p ^ *src2p 544 * @dstp: the cpumask result 545 * @src1p: the first input 546 * @src2p: the second input 547 */ 548 static inline void cpumask_xor(struct cpumask *dstp, 549 const struct cpumask *src1p, 550 const struct cpumask *src2p) 551 { 552 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p), 553 cpumask_bits(src2p), nr_cpumask_bits); 554 } 555 556 /** 557 * cpumask_andnot - *dstp = *src1p & ~*src2p 558 * @dstp: the cpumask result 559 * @src1p: the first input 560 * @src2p: the second input 561 * 562 * If *@dstp is empty, returns false, else returns true 563 */ 564 static inline bool cpumask_andnot(struct cpumask *dstp, 565 const struct cpumask *src1p, 566 const struct cpumask *src2p) 567 { 568 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p), 569 cpumask_bits(src2p), nr_cpumask_bits); 570 } 571 572 /** 573 * cpumask_complement - *dstp = ~*srcp 574 * @dstp: the cpumask result 575 * @srcp: the input to invert 576 */ 577 static inline void cpumask_complement(struct cpumask *dstp, 578 const struct cpumask *srcp) 579 { 580 bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp), 581 nr_cpumask_bits); 582 } 583 584 /** 585 * cpumask_equal - *src1p == *src2p 586 * @src1p: the first input 587 * @src2p: the second input 588 */ 589 static inline bool cpumask_equal(const struct cpumask *src1p, 590 const struct cpumask *src2p) 591 { 592 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p), 593 nr_cpumask_bits); 594 } 595 596 /** 597 * cpumask_or_equal - *src1p | *src2p == *src3p 598 * @src1p: the first input 599 * @src2p: the second input 600 * @src3p: the third input 601 */ 602 static inline bool cpumask_or_equal(const struct cpumask *src1p, 603 const struct cpumask *src2p, 604 const struct cpumask *src3p) 605 { 606 return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p), 607 cpumask_bits(src3p), nr_cpumask_bits); 608 } 609 610 /** 611 * cpumask_intersects - (*src1p & *src2p) != 0 612 * @src1p: the first input 613 * @src2p: the second input 614 */ 615 static inline bool cpumask_intersects(const struct cpumask *src1p, 616 const struct cpumask *src2p) 617 { 618 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p), 619 nr_cpumask_bits); 620 } 621 622 /** 623 * cpumask_subset - (*src1p & ~*src2p) == 0 624 * @src1p: the first input 625 * @src2p: the second input 626 * 627 * Returns true if *@src1p is a subset of *@src2p, else returns false 628 */ 629 static inline bool cpumask_subset(const struct cpumask *src1p, 630 const struct cpumask *src2p) 631 { 632 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p), 633 nr_cpumask_bits); 634 } 635 636 /** 637 * cpumask_empty - *srcp == 0 638 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear. 639 */ 640 static inline bool cpumask_empty(const struct cpumask *srcp) 641 { 642 return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits); 643 } 644 645 /** 646 * cpumask_full - *srcp == 0xFFFFFFFF... 647 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set. 648 */ 649 static inline bool cpumask_full(const struct cpumask *srcp) 650 { 651 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits); 652 } 653 654 /** 655 * cpumask_weight - Count of bits in *srcp 656 * @srcp: the cpumask to count bits (< nr_cpu_ids) in. 657 */ 658 static inline unsigned int cpumask_weight(const struct cpumask *srcp) 659 { 660 return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits); 661 } 662 663 /** 664 * cpumask_weight_and - Count of bits in (*srcp1 & *srcp2) 665 * @srcp1: the cpumask to count bits (< nr_cpu_ids) in. 666 * @srcp2: the cpumask to count bits (< nr_cpu_ids) in. 667 */ 668 static inline unsigned int cpumask_weight_and(const struct cpumask *srcp1, 669 const struct cpumask *srcp2) 670 { 671 return bitmap_weight_and(cpumask_bits(srcp1), cpumask_bits(srcp2), nr_cpumask_bits); 672 } 673 674 /** 675 * cpumask_shift_right - *dstp = *srcp >> n 676 * @dstp: the cpumask result 677 * @srcp: the input to shift 678 * @n: the number of bits to shift by 679 */ 680 static inline void cpumask_shift_right(struct cpumask *dstp, 681 const struct cpumask *srcp, int n) 682 { 683 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n, 684 nr_cpumask_bits); 685 } 686 687 /** 688 * cpumask_shift_left - *dstp = *srcp << n 689 * @dstp: the cpumask result 690 * @srcp: the input to shift 691 * @n: the number of bits to shift by 692 */ 693 static inline void cpumask_shift_left(struct cpumask *dstp, 694 const struct cpumask *srcp, int n) 695 { 696 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n, 697 nr_cpumask_bits); 698 } 699 700 /** 701 * cpumask_copy - *dstp = *srcp 702 * @dstp: the result 703 * @srcp: the input cpumask 704 */ 705 static inline void cpumask_copy(struct cpumask *dstp, 706 const struct cpumask *srcp) 707 { 708 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits); 709 } 710 711 /** 712 * cpumask_any - pick a "random" cpu from *srcp 713 * @srcp: the input cpumask 714 * 715 * Returns >= nr_cpu_ids if no cpus set. 716 */ 717 #define cpumask_any(srcp) cpumask_first(srcp) 718 719 /** 720 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2 721 * @mask1: the first input cpumask 722 * @mask2: the second input cpumask 723 * 724 * Returns >= nr_cpu_ids if no cpus set. 725 */ 726 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2)) 727 728 /** 729 * cpumask_of - the cpumask containing just a given cpu 730 * @cpu: the cpu (<= nr_cpu_ids) 731 */ 732 #define cpumask_of(cpu) (get_cpu_mask(cpu)) 733 734 /** 735 * cpumask_parse_user - extract a cpumask from a user string 736 * @buf: the buffer to extract from 737 * @len: the length of the buffer 738 * @dstp: the cpumask to set. 739 * 740 * Returns -errno, or 0 for success. 741 */ 742 static inline int cpumask_parse_user(const char __user *buf, int len, 743 struct cpumask *dstp) 744 { 745 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits); 746 } 747 748 /** 749 * cpumask_parselist_user - extract a cpumask from a user string 750 * @buf: the buffer to extract from 751 * @len: the length of the buffer 752 * @dstp: the cpumask to set. 753 * 754 * Returns -errno, or 0 for success. 755 */ 756 static inline int cpumask_parselist_user(const char __user *buf, int len, 757 struct cpumask *dstp) 758 { 759 return bitmap_parselist_user(buf, len, cpumask_bits(dstp), 760 nr_cpumask_bits); 761 } 762 763 /** 764 * cpumask_parse - extract a cpumask from a string 765 * @buf: the buffer to extract from 766 * @dstp: the cpumask to set. 767 * 768 * Returns -errno, or 0 for success. 769 */ 770 static inline int cpumask_parse(const char *buf, struct cpumask *dstp) 771 { 772 return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits); 773 } 774 775 /** 776 * cpulist_parse - extract a cpumask from a user string of ranges 777 * @buf: the buffer to extract from 778 * @dstp: the cpumask to set. 779 * 780 * Returns -errno, or 0 for success. 781 */ 782 static inline int cpulist_parse(const char *buf, struct cpumask *dstp) 783 { 784 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits); 785 } 786 787 /** 788 * cpumask_size - size to allocate for a 'struct cpumask' in bytes 789 */ 790 static inline unsigned int cpumask_size(void) 791 { 792 return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long); 793 } 794 795 /* 796 * cpumask_var_t: struct cpumask for stack usage. 797 * 798 * Oh, the wicked games we play! In order to make kernel coding a 799 * little more difficult, we typedef cpumask_var_t to an array or a 800 * pointer: doing &mask on an array is a noop, so it still works. 801 * 802 * ie. 803 * cpumask_var_t tmpmask; 804 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 805 * return -ENOMEM; 806 * 807 * ... use 'tmpmask' like a normal struct cpumask * ... 808 * 809 * free_cpumask_var(tmpmask); 810 * 811 * 812 * However, one notable exception is there. alloc_cpumask_var() allocates 813 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has 814 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t. 815 * 816 * cpumask_var_t tmpmask; 817 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 818 * return -ENOMEM; 819 * 820 * var = *tmpmask; 821 * 822 * This code makes NR_CPUS length memcopy and brings to a memory corruption. 823 * cpumask_copy() provide safe copy functionality. 824 * 825 * Note that there is another evil here: If you define a cpumask_var_t 826 * as a percpu variable then the way to obtain the address of the cpumask 827 * structure differently influences what this_cpu_* operation needs to be 828 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use 829 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the 830 * other type of cpumask_var_t implementation is configured. 831 * 832 * Please also note that __cpumask_var_read_mostly can be used to declare 833 * a cpumask_var_t variable itself (not its content) as read mostly. 834 */ 835 #ifdef CONFIG_CPUMASK_OFFSTACK 836 typedef struct cpumask *cpumask_var_t; 837 838 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x) 839 #define __cpumask_var_read_mostly __read_mostly 840 841 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); 842 843 static inline 844 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node) 845 { 846 return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node); 847 } 848 849 /** 850 * alloc_cpumask_var - allocate a struct cpumask 851 * @mask: pointer to cpumask_var_t where the cpumask is returned 852 * @flags: GFP_ flags 853 * 854 * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is 855 * a nop returning a constant 1 (in <linux/cpumask.h>). 856 * 857 * See alloc_cpumask_var_node. 858 */ 859 static inline 860 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 861 { 862 return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE); 863 } 864 865 static inline 866 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 867 { 868 return alloc_cpumask_var(mask, flags | __GFP_ZERO); 869 } 870 871 void alloc_bootmem_cpumask_var(cpumask_var_t *mask); 872 void free_cpumask_var(cpumask_var_t mask); 873 void free_bootmem_cpumask_var(cpumask_var_t mask); 874 875 static inline bool cpumask_available(cpumask_var_t mask) 876 { 877 return mask != NULL; 878 } 879 880 #else 881 typedef struct cpumask cpumask_var_t[1]; 882 883 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x) 884 #define __cpumask_var_read_mostly 885 886 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 887 { 888 return true; 889 } 890 891 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 892 int node) 893 { 894 return true; 895 } 896 897 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 898 { 899 cpumask_clear(*mask); 900 return true; 901 } 902 903 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 904 int node) 905 { 906 cpumask_clear(*mask); 907 return true; 908 } 909 910 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask) 911 { 912 } 913 914 static inline void free_cpumask_var(cpumask_var_t mask) 915 { 916 } 917 918 static inline void free_bootmem_cpumask_var(cpumask_var_t mask) 919 { 920 } 921 922 static inline bool cpumask_available(cpumask_var_t mask) 923 { 924 return true; 925 } 926 #endif /* CONFIG_CPUMASK_OFFSTACK */ 927 928 /* It's common to want to use cpu_all_mask in struct member initializers, 929 * so it has to refer to an address rather than a pointer. */ 930 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS); 931 #define cpu_all_mask to_cpumask(cpu_all_bits) 932 933 /* First bits of cpu_bit_bitmap are in fact unset. */ 934 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0]) 935 936 #if NR_CPUS == 1 937 /* Uniprocessor: the possible/online/present masks are always "1" */ 938 #define for_each_possible_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++) 939 #define for_each_online_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++) 940 #define for_each_present_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++) 941 #else 942 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask) 943 #define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask) 944 #define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask) 945 #endif 946 947 /* Wrappers for arch boot code to manipulate normally-constant masks */ 948 void init_cpu_present(const struct cpumask *src); 949 void init_cpu_possible(const struct cpumask *src); 950 void init_cpu_online(const struct cpumask *src); 951 952 static inline void reset_cpu_possible_mask(void) 953 { 954 bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS); 955 } 956 957 static inline void 958 set_cpu_possible(unsigned int cpu, bool possible) 959 { 960 if (possible) 961 cpumask_set_cpu(cpu, &__cpu_possible_mask); 962 else 963 cpumask_clear_cpu(cpu, &__cpu_possible_mask); 964 } 965 966 static inline void 967 set_cpu_present(unsigned int cpu, bool present) 968 { 969 if (present) 970 cpumask_set_cpu(cpu, &__cpu_present_mask); 971 else 972 cpumask_clear_cpu(cpu, &__cpu_present_mask); 973 } 974 975 void set_cpu_online(unsigned int cpu, bool online); 976 977 static inline void 978 set_cpu_active(unsigned int cpu, bool active) 979 { 980 if (active) 981 cpumask_set_cpu(cpu, &__cpu_active_mask); 982 else 983 cpumask_clear_cpu(cpu, &__cpu_active_mask); 984 } 985 986 static inline void 987 set_cpu_dying(unsigned int cpu, bool dying) 988 { 989 if (dying) 990 cpumask_set_cpu(cpu, &__cpu_dying_mask); 991 else 992 cpumask_clear_cpu(cpu, &__cpu_dying_mask); 993 } 994 995 /** 996 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask * 997 * @bitmap: the bitmap 998 * 999 * There are a few places where cpumask_var_t isn't appropriate and 1000 * static cpumasks must be used (eg. very early boot), yet we don't 1001 * expose the definition of 'struct cpumask'. 1002 * 1003 * This does the conversion, and can be used as a constant initializer. 1004 */ 1005 #define to_cpumask(bitmap) \ 1006 ((struct cpumask *)(1 ? (bitmap) \ 1007 : (void *)sizeof(__check_is_bitmap(bitmap)))) 1008 1009 static inline int __check_is_bitmap(const unsigned long *bitmap) 1010 { 1011 return 1; 1012 } 1013 1014 /* 1015 * Special-case data structure for "single bit set only" constant CPU masks. 1016 * 1017 * We pre-generate all the 64 (or 32) possible bit positions, with enough 1018 * padding to the left and the right, and return the constant pointer 1019 * appropriately offset. 1020 */ 1021 extern const unsigned long 1022 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)]; 1023 1024 static inline const struct cpumask *get_cpu_mask(unsigned int cpu) 1025 { 1026 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; 1027 p -= cpu / BITS_PER_LONG; 1028 return to_cpumask(p); 1029 } 1030 1031 #if NR_CPUS > 1 1032 /** 1033 * num_online_cpus() - Read the number of online CPUs 1034 * 1035 * Despite the fact that __num_online_cpus is of type atomic_t, this 1036 * interface gives only a momentary snapshot and is not protected against 1037 * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held 1038 * region. 1039 */ 1040 static __always_inline unsigned int num_online_cpus(void) 1041 { 1042 return arch_atomic_read(&__num_online_cpus); 1043 } 1044 #define num_possible_cpus() cpumask_weight(cpu_possible_mask) 1045 #define num_present_cpus() cpumask_weight(cpu_present_mask) 1046 #define num_active_cpus() cpumask_weight(cpu_active_mask) 1047 1048 static inline bool cpu_online(unsigned int cpu) 1049 { 1050 return cpumask_test_cpu(cpu, cpu_online_mask); 1051 } 1052 1053 static inline bool cpu_possible(unsigned int cpu) 1054 { 1055 return cpumask_test_cpu(cpu, cpu_possible_mask); 1056 } 1057 1058 static inline bool cpu_present(unsigned int cpu) 1059 { 1060 return cpumask_test_cpu(cpu, cpu_present_mask); 1061 } 1062 1063 static inline bool cpu_active(unsigned int cpu) 1064 { 1065 return cpumask_test_cpu(cpu, cpu_active_mask); 1066 } 1067 1068 static inline bool cpu_dying(unsigned int cpu) 1069 { 1070 return cpumask_test_cpu(cpu, cpu_dying_mask); 1071 } 1072 1073 #else 1074 1075 #define num_online_cpus() 1U 1076 #define num_possible_cpus() 1U 1077 #define num_present_cpus() 1U 1078 #define num_active_cpus() 1U 1079 1080 static inline bool cpu_online(unsigned int cpu) 1081 { 1082 return cpu == 0; 1083 } 1084 1085 static inline bool cpu_possible(unsigned int cpu) 1086 { 1087 return cpu == 0; 1088 } 1089 1090 static inline bool cpu_present(unsigned int cpu) 1091 { 1092 return cpu == 0; 1093 } 1094 1095 static inline bool cpu_active(unsigned int cpu) 1096 { 1097 return cpu == 0; 1098 } 1099 1100 static inline bool cpu_dying(unsigned int cpu) 1101 { 1102 return false; 1103 } 1104 1105 #endif /* NR_CPUS > 1 */ 1106 1107 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu)) 1108 1109 #if NR_CPUS <= BITS_PER_LONG 1110 #define CPU_BITS_ALL \ 1111 { \ 1112 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 1113 } 1114 1115 #else /* NR_CPUS > BITS_PER_LONG */ 1116 1117 #define CPU_BITS_ALL \ 1118 { \ 1119 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 1120 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 1121 } 1122 #endif /* NR_CPUS > BITS_PER_LONG */ 1123 1124 /** 1125 * cpumap_print_to_pagebuf - copies the cpumask into the buffer either 1126 * as comma-separated list of cpus or hex values of cpumask 1127 * @list: indicates whether the cpumap must be list 1128 * @mask: the cpumask to copy 1129 * @buf: the buffer to copy into 1130 * 1131 * Returns the length of the (null-terminated) @buf string, zero if 1132 * nothing is copied. 1133 */ 1134 static inline ssize_t 1135 cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask) 1136 { 1137 return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask), 1138 nr_cpu_ids); 1139 } 1140 1141 /** 1142 * cpumap_print_bitmask_to_buf - copies the cpumask into the buffer as 1143 * hex values of cpumask 1144 * 1145 * @buf: the buffer to copy into 1146 * @mask: the cpumask to copy 1147 * @off: in the string from which we are copying, we copy to @buf 1148 * @count: the maximum number of bytes to print 1149 * 1150 * The function prints the cpumask into the buffer as hex values of 1151 * cpumask; Typically used by bin_attribute to export cpumask bitmask 1152 * ABI. 1153 * 1154 * Returns the length of how many bytes have been copied, excluding 1155 * terminating '\0'. 1156 */ 1157 static inline ssize_t 1158 cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask, 1159 loff_t off, size_t count) 1160 { 1161 return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask), 1162 nr_cpu_ids, off, count) - 1; 1163 } 1164 1165 /** 1166 * cpumap_print_list_to_buf - copies the cpumask into the buffer as 1167 * comma-separated list of cpus 1168 * 1169 * Everything is same with the above cpumap_print_bitmask_to_buf() 1170 * except the print format. 1171 */ 1172 static inline ssize_t 1173 cpumap_print_list_to_buf(char *buf, const struct cpumask *mask, 1174 loff_t off, size_t count) 1175 { 1176 return bitmap_print_list_to_buf(buf, cpumask_bits(mask), 1177 nr_cpu_ids, off, count) - 1; 1178 } 1179 1180 #if NR_CPUS <= BITS_PER_LONG 1181 #define CPU_MASK_ALL \ 1182 (cpumask_t) { { \ 1183 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 1184 } } 1185 #else 1186 #define CPU_MASK_ALL \ 1187 (cpumask_t) { { \ 1188 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 1189 [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ 1190 } } 1191 #endif /* NR_CPUS > BITS_PER_LONG */ 1192 1193 #define CPU_MASK_NONE \ 1194 (cpumask_t) { { \ 1195 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 1196 } } 1197 1198 #define CPU_MASK_CPU0 \ 1199 (cpumask_t) { { \ 1200 [0] = 1UL \ 1201 } } 1202 1203 /* 1204 * Provide a valid theoretical max size for cpumap and cpulist sysfs files 1205 * to avoid breaking userspace which may allocate a buffer based on the size 1206 * reported by e.g. fstat. 1207 * 1208 * for cpumap NR_CPUS * 9/32 - 1 should be an exact length. 1209 * 1210 * For cpulist 7 is (ceil(log10(NR_CPUS)) + 1) allowing for NR_CPUS to be up 1211 * to 2 orders of magnitude larger than 8192. And then we divide by 2 to 1212 * cover a worst-case of every other cpu being on one of two nodes for a 1213 * very large NR_CPUS. 1214 * 1215 * Use PAGE_SIZE as a minimum for smaller configurations while avoiding 1216 * unsigned comparison to -1. 1217 */ 1218 #define CPUMAP_FILE_MAX_BYTES (((NR_CPUS * 9)/32 > PAGE_SIZE) \ 1219 ? (NR_CPUS * 9)/32 - 1 : PAGE_SIZE) 1220 #define CPULIST_FILE_MAX_BYTES (((NR_CPUS * 7)/2 > PAGE_SIZE) ? (NR_CPUS * 7)/2 : PAGE_SIZE) 1221 1222 #endif /* __LINUX_CPUMASK_H */ 1223