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