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