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 typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t; 15 16 /** 17 * cpumask_bits - get the bits in a cpumask 18 * @maskp: the struct cpumask * 19 * 20 * You should only assume nr_cpu_ids bits of this mask are valid. This is 21 * a macro so it's const-correct. 22 */ 23 #define cpumask_bits(maskp) ((maskp)->bits) 24 25 #if NR_CPUS == 1 26 #define nr_cpu_ids 1 27 #else 28 extern int nr_cpu_ids; 29 #endif 30 31 #ifdef CONFIG_CPUMASK_OFFSTACK 32 /* Assuming NR_CPUS is huge, a runtime limit is more efficient. Also, 33 * not all bits may be allocated. */ 34 #define nr_cpumask_bits nr_cpu_ids 35 #else 36 #define nr_cpumask_bits NR_CPUS 37 #endif 38 39 /* 40 * The following particular system cpumasks and operations manage 41 * possible, present, active and online cpus. 42 * 43 * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable 44 * cpu_present_mask - has bit 'cpu' set iff cpu is populated 45 * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler 46 * cpu_active_mask - has bit 'cpu' set iff cpu available to migration 47 * 48 * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online. 49 * 50 * The cpu_possible_mask is fixed at boot time, as the set of CPU id's 51 * that it is possible might ever be plugged in at anytime during the 52 * life of that system boot. The cpu_present_mask is dynamic(*), 53 * representing which CPUs are currently plugged in. And 54 * cpu_online_mask is the dynamic subset of cpu_present_mask, 55 * indicating those CPUs available for scheduling. 56 * 57 * If HOTPLUG is enabled, then cpu_possible_mask is forced to have 58 * all NR_CPUS bits set, otherwise it is just the set of CPUs that 59 * ACPI reports present at boot. 60 * 61 * If HOTPLUG is enabled, then cpu_present_mask varies dynamically, 62 * depending on what ACPI reports as currently plugged in, otherwise 63 * cpu_present_mask is just a copy of cpu_possible_mask. 64 * 65 * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not 66 * hotplug, it's a copy of cpu_possible_mask, hence fixed at boot. 67 * 68 * Subtleties: 69 * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode 70 * assumption that their single CPU is online. The UP 71 * cpu_{online,possible,present}_masks are placebos. Changing them 72 * will have no useful affect on the following num_*_cpus() 73 * and cpu_*() macros in the UP case. This ugliness is a UP 74 * optimization - don't waste any instructions or memory references 75 * asking if you're online or how many CPUs there are if there is 76 * only one CPU. 77 */ 78 79 extern const struct cpumask *const cpu_possible_mask; 80 extern const struct cpumask *const cpu_online_mask; 81 extern const struct cpumask *const cpu_present_mask; 82 extern const struct cpumask *const cpu_active_mask; 83 84 #if NR_CPUS > 1 85 #define num_online_cpus() cpumask_weight(cpu_online_mask) 86 #define num_possible_cpus() cpumask_weight(cpu_possible_mask) 87 #define num_present_cpus() cpumask_weight(cpu_present_mask) 88 #define num_active_cpus() cpumask_weight(cpu_active_mask) 89 #define cpu_online(cpu) cpumask_test_cpu((cpu), cpu_online_mask) 90 #define cpu_possible(cpu) cpumask_test_cpu((cpu), cpu_possible_mask) 91 #define cpu_present(cpu) cpumask_test_cpu((cpu), cpu_present_mask) 92 #define cpu_active(cpu) cpumask_test_cpu((cpu), cpu_active_mask) 93 #else 94 #define num_online_cpus() 1U 95 #define num_possible_cpus() 1U 96 #define num_present_cpus() 1U 97 #define num_active_cpus() 1U 98 #define cpu_online(cpu) ((cpu) == 0) 99 #define cpu_possible(cpu) ((cpu) == 0) 100 #define cpu_present(cpu) ((cpu) == 0) 101 #define cpu_active(cpu) ((cpu) == 0) 102 #endif 103 104 /* verify cpu argument to cpumask_* operators */ 105 static inline unsigned int cpumask_check(unsigned int cpu) 106 { 107 #ifdef CONFIG_DEBUG_PER_CPU_MAPS 108 WARN_ON_ONCE(cpu >= nr_cpumask_bits); 109 #endif /* CONFIG_DEBUG_PER_CPU_MAPS */ 110 return cpu; 111 } 112 113 #if NR_CPUS == 1 114 /* Uniprocessor. Assume all masks are "1". */ 115 static inline unsigned int cpumask_first(const struct cpumask *srcp) 116 { 117 return 0; 118 } 119 120 /* Valid inputs for n are -1 and 0. */ 121 static inline unsigned int cpumask_next(int n, const struct cpumask *srcp) 122 { 123 return n+1; 124 } 125 126 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) 127 { 128 return n+1; 129 } 130 131 static inline unsigned int cpumask_next_and(int n, 132 const struct cpumask *srcp, 133 const struct cpumask *andp) 134 { 135 return n+1; 136 } 137 138 /* cpu must be a valid cpu, ie 0, so there's no other choice. */ 139 static inline unsigned int cpumask_any_but(const struct cpumask *mask, 140 unsigned int cpu) 141 { 142 return 1; 143 } 144 145 static inline int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp) 146 { 147 set_bit(0, cpumask_bits(dstp)); 148 149 return 0; 150 } 151 152 #define for_each_cpu(cpu, mask) \ 153 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) 154 #define for_each_cpu_not(cpu, mask) \ 155 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) 156 #define for_each_cpu_and(cpu, mask, and) \ 157 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)and) 158 #else 159 /** 160 * cpumask_first - get the first cpu in a cpumask 161 * @srcp: the cpumask pointer 162 * 163 * Returns >= nr_cpu_ids if no cpus set. 164 */ 165 static inline unsigned int cpumask_first(const struct cpumask *srcp) 166 { 167 return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits); 168 } 169 170 /** 171 * cpumask_next - get the next cpu in a cpumask 172 * @n: the cpu prior to the place to search (ie. return will be > @n) 173 * @srcp: the cpumask pointer 174 * 175 * Returns >= nr_cpu_ids if no further cpus set. 176 */ 177 static inline unsigned int cpumask_next(int n, const struct cpumask *srcp) 178 { 179 /* -1 is a legal arg here. */ 180 if (n != -1) 181 cpumask_check(n); 182 return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1); 183 } 184 185 /** 186 * cpumask_next_zero - get the next unset cpu in a cpumask 187 * @n: the cpu prior to the place to search (ie. return will be > @n) 188 * @srcp: the cpumask pointer 189 * 190 * Returns >= nr_cpu_ids if no further cpus unset. 191 */ 192 static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp) 193 { 194 /* -1 is a legal arg here. */ 195 if (n != -1) 196 cpumask_check(n); 197 return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1); 198 } 199 200 int cpumask_next_and(int n, const struct cpumask *, const struct cpumask *); 201 int cpumask_any_but(const struct cpumask *mask, unsigned int cpu); 202 int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp); 203 204 /** 205 * for_each_cpu - iterate over every cpu in a mask 206 * @cpu: the (optionally unsigned) integer iterator 207 * @mask: the cpumask pointer 208 * 209 * After the loop, cpu is >= nr_cpu_ids. 210 */ 211 #define for_each_cpu(cpu, mask) \ 212 for ((cpu) = -1; \ 213 (cpu) = cpumask_next((cpu), (mask)), \ 214 (cpu) < nr_cpu_ids;) 215 216 /** 217 * for_each_cpu_not - iterate over every cpu in a complemented mask 218 * @cpu: the (optionally unsigned) integer iterator 219 * @mask: the cpumask pointer 220 * 221 * After the loop, cpu is >= nr_cpu_ids. 222 */ 223 #define for_each_cpu_not(cpu, mask) \ 224 for ((cpu) = -1; \ 225 (cpu) = cpumask_next_zero((cpu), (mask)), \ 226 (cpu) < nr_cpu_ids;) 227 228 /** 229 * for_each_cpu_and - iterate over every cpu in both masks 230 * @cpu: the (optionally unsigned) integer iterator 231 * @mask: the first cpumask pointer 232 * @and: the second cpumask pointer 233 * 234 * This saves a temporary CPU mask in many places. It is equivalent to: 235 * struct cpumask tmp; 236 * cpumask_and(&tmp, &mask, &and); 237 * for_each_cpu(cpu, &tmp) 238 * ... 239 * 240 * After the loop, cpu is >= nr_cpu_ids. 241 */ 242 #define for_each_cpu_and(cpu, mask, and) \ 243 for ((cpu) = -1; \ 244 (cpu) = cpumask_next_and((cpu), (mask), (and)), \ 245 (cpu) < nr_cpu_ids;) 246 #endif /* SMP */ 247 248 #define CPU_BITS_NONE \ 249 { \ 250 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 251 } 252 253 #define CPU_BITS_CPU0 \ 254 { \ 255 [0] = 1UL \ 256 } 257 258 /** 259 * cpumask_set_cpu - set a cpu in a cpumask 260 * @cpu: cpu number (< nr_cpu_ids) 261 * @dstp: the cpumask pointer 262 */ 263 static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 264 { 265 set_bit(cpumask_check(cpu), cpumask_bits(dstp)); 266 } 267 268 /** 269 * cpumask_clear_cpu - clear a cpu in a cpumask 270 * @cpu: cpu number (< nr_cpu_ids) 271 * @dstp: the cpumask pointer 272 */ 273 static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp) 274 { 275 clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); 276 } 277 278 /** 279 * cpumask_test_cpu - test for a cpu in a cpumask 280 * @cpu: cpu number (< nr_cpu_ids) 281 * @cpumask: the cpumask pointer 282 * 283 * Returns 1 if @cpu is set in @cpumask, else returns 0 284 * 285 * No static inline type checking - see Subtlety (1) above. 286 */ 287 #define cpumask_test_cpu(cpu, cpumask) \ 288 test_bit(cpumask_check(cpu), cpumask_bits((cpumask))) 289 290 /** 291 * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask 292 * @cpu: cpu number (< nr_cpu_ids) 293 * @cpumask: the cpumask pointer 294 * 295 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0 296 * 297 * test_and_set_bit wrapper for cpumasks. 298 */ 299 static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask) 300 { 301 return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 302 } 303 304 /** 305 * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask 306 * @cpu: cpu number (< nr_cpu_ids) 307 * @cpumask: the cpumask pointer 308 * 309 * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0 310 * 311 * test_and_clear_bit wrapper for cpumasks. 312 */ 313 static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask) 314 { 315 return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask)); 316 } 317 318 /** 319 * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask 320 * @dstp: the cpumask pointer 321 */ 322 static inline void cpumask_setall(struct cpumask *dstp) 323 { 324 bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits); 325 } 326 327 /** 328 * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask 329 * @dstp: the cpumask pointer 330 */ 331 static inline void cpumask_clear(struct cpumask *dstp) 332 { 333 bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits); 334 } 335 336 /** 337 * cpumask_and - *dstp = *src1p & *src2p 338 * @dstp: the cpumask result 339 * @src1p: the first input 340 * @src2p: the second input 341 * 342 * If *@dstp is empty, returns 0, else returns 1 343 */ 344 static inline int cpumask_and(struct cpumask *dstp, 345 const struct cpumask *src1p, 346 const struct cpumask *src2p) 347 { 348 return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p), 349 cpumask_bits(src2p), nr_cpumask_bits); 350 } 351 352 /** 353 * cpumask_or - *dstp = *src1p | *src2p 354 * @dstp: the cpumask result 355 * @src1p: the first input 356 * @src2p: the second input 357 */ 358 static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p, 359 const struct cpumask *src2p) 360 { 361 bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p), 362 cpumask_bits(src2p), nr_cpumask_bits); 363 } 364 365 /** 366 * cpumask_xor - *dstp = *src1p ^ *src2p 367 * @dstp: the cpumask result 368 * @src1p: the first input 369 * @src2p: the second input 370 */ 371 static inline void cpumask_xor(struct cpumask *dstp, 372 const struct cpumask *src1p, 373 const struct cpumask *src2p) 374 { 375 bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p), 376 cpumask_bits(src2p), nr_cpumask_bits); 377 } 378 379 /** 380 * cpumask_andnot - *dstp = *src1p & ~*src2p 381 * @dstp: the cpumask result 382 * @src1p: the first input 383 * @src2p: the second input 384 * 385 * If *@dstp is empty, returns 0, else returns 1 386 */ 387 static inline int cpumask_andnot(struct cpumask *dstp, 388 const struct cpumask *src1p, 389 const struct cpumask *src2p) 390 { 391 return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p), 392 cpumask_bits(src2p), nr_cpumask_bits); 393 } 394 395 /** 396 * cpumask_complement - *dstp = ~*srcp 397 * @dstp: the cpumask result 398 * @srcp: the input to invert 399 */ 400 static inline void cpumask_complement(struct cpumask *dstp, 401 const struct cpumask *srcp) 402 { 403 bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp), 404 nr_cpumask_bits); 405 } 406 407 /** 408 * cpumask_equal - *src1p == *src2p 409 * @src1p: the first input 410 * @src2p: the second input 411 */ 412 static inline bool cpumask_equal(const struct cpumask *src1p, 413 const struct cpumask *src2p) 414 { 415 return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p), 416 nr_cpumask_bits); 417 } 418 419 /** 420 * cpumask_intersects - (*src1p & *src2p) != 0 421 * @src1p: the first input 422 * @src2p: the second input 423 */ 424 static inline bool cpumask_intersects(const struct cpumask *src1p, 425 const struct cpumask *src2p) 426 { 427 return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p), 428 nr_cpumask_bits); 429 } 430 431 /** 432 * cpumask_subset - (*src1p & ~*src2p) == 0 433 * @src1p: the first input 434 * @src2p: the second input 435 * 436 * Returns 1 if *@src1p is a subset of *@src2p, else returns 0 437 */ 438 static inline int cpumask_subset(const struct cpumask *src1p, 439 const struct cpumask *src2p) 440 { 441 return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p), 442 nr_cpumask_bits); 443 } 444 445 /** 446 * cpumask_empty - *srcp == 0 447 * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear. 448 */ 449 static inline bool cpumask_empty(const struct cpumask *srcp) 450 { 451 return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits); 452 } 453 454 /** 455 * cpumask_full - *srcp == 0xFFFFFFFF... 456 * @srcp: the cpumask to that all cpus < nr_cpu_ids are set. 457 */ 458 static inline bool cpumask_full(const struct cpumask *srcp) 459 { 460 return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits); 461 } 462 463 /** 464 * cpumask_weight - Count of bits in *srcp 465 * @srcp: the cpumask to count bits (< nr_cpu_ids) in. 466 */ 467 static inline unsigned int cpumask_weight(const struct cpumask *srcp) 468 { 469 return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits); 470 } 471 472 /** 473 * cpumask_shift_right - *dstp = *srcp >> n 474 * @dstp: the cpumask result 475 * @srcp: the input to shift 476 * @n: the number of bits to shift by 477 */ 478 static inline void cpumask_shift_right(struct cpumask *dstp, 479 const struct cpumask *srcp, int n) 480 { 481 bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n, 482 nr_cpumask_bits); 483 } 484 485 /** 486 * cpumask_shift_left - *dstp = *srcp << n 487 * @dstp: the cpumask result 488 * @srcp: the input to shift 489 * @n: the number of bits to shift by 490 */ 491 static inline void cpumask_shift_left(struct cpumask *dstp, 492 const struct cpumask *srcp, int n) 493 { 494 bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n, 495 nr_cpumask_bits); 496 } 497 498 /** 499 * cpumask_copy - *dstp = *srcp 500 * @dstp: the result 501 * @srcp: the input cpumask 502 */ 503 static inline void cpumask_copy(struct cpumask *dstp, 504 const struct cpumask *srcp) 505 { 506 bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits); 507 } 508 509 /** 510 * cpumask_any - pick a "random" cpu from *srcp 511 * @srcp: the input cpumask 512 * 513 * Returns >= nr_cpu_ids if no cpus set. 514 */ 515 #define cpumask_any(srcp) cpumask_first(srcp) 516 517 /** 518 * cpumask_first_and - return the first cpu from *srcp1 & *srcp2 519 * @src1p: the first input 520 * @src2p: the second input 521 * 522 * Returns >= nr_cpu_ids if no cpus set in both. See also cpumask_next_and(). 523 */ 524 #define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p)) 525 526 /** 527 * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2 528 * @mask1: the first input cpumask 529 * @mask2: the second input cpumask 530 * 531 * Returns >= nr_cpu_ids if no cpus set. 532 */ 533 #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2)) 534 535 /** 536 * cpumask_of - the cpumask containing just a given cpu 537 * @cpu: the cpu (<= nr_cpu_ids) 538 */ 539 #define cpumask_of(cpu) (get_cpu_mask(cpu)) 540 541 /** 542 * cpumask_scnprintf - print a cpumask into a string as comma-separated hex 543 * @buf: the buffer to sprintf into 544 * @len: the length of the buffer 545 * @srcp: the cpumask to print 546 * 547 * If len is zero, returns zero. Otherwise returns the length of the 548 * (nul-terminated) @buf string. 549 */ 550 static inline int cpumask_scnprintf(char *buf, int len, 551 const struct cpumask *srcp) 552 { 553 return bitmap_scnprintf(buf, len, cpumask_bits(srcp), nr_cpumask_bits); 554 } 555 556 /** 557 * cpumask_parse_user - extract a cpumask from a user string 558 * @buf: the buffer to extract from 559 * @len: the length of the buffer 560 * @dstp: the cpumask to set. 561 * 562 * Returns -errno, or 0 for success. 563 */ 564 static inline int cpumask_parse_user(const char __user *buf, int len, 565 struct cpumask *dstp) 566 { 567 return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits); 568 } 569 570 /** 571 * cpumask_parselist_user - extract a cpumask from a user string 572 * @buf: the buffer to extract from 573 * @len: the length of the buffer 574 * @dstp: the cpumask to set. 575 * 576 * Returns -errno, or 0 for success. 577 */ 578 static inline int cpumask_parselist_user(const char __user *buf, int len, 579 struct cpumask *dstp) 580 { 581 return bitmap_parselist_user(buf, len, cpumask_bits(dstp), 582 nr_cpumask_bits); 583 } 584 585 /** 586 * cpulist_scnprintf - print a cpumask into a string as comma-separated list 587 * @buf: the buffer to sprintf into 588 * @len: the length of the buffer 589 * @srcp: the cpumask to print 590 * 591 * If len is zero, returns zero. Otherwise returns the length of the 592 * (nul-terminated) @buf string. 593 */ 594 static inline int cpulist_scnprintf(char *buf, int len, 595 const struct cpumask *srcp) 596 { 597 return bitmap_scnlistprintf(buf, len, cpumask_bits(srcp), 598 nr_cpumask_bits); 599 } 600 601 /** 602 * cpumask_parse - extract a cpumask from from a string 603 * @buf: the buffer to extract from 604 * @dstp: the cpumask to set. 605 * 606 * Returns -errno, or 0 for success. 607 */ 608 static inline int cpumask_parse(const char *buf, struct cpumask *dstp) 609 { 610 char *nl = strchr(buf, '\n'); 611 unsigned int len = nl ? (unsigned int)(nl - buf) : strlen(buf); 612 613 return bitmap_parse(buf, len, cpumask_bits(dstp), nr_cpumask_bits); 614 } 615 616 /** 617 * cpulist_parse - extract a cpumask from a user string of ranges 618 * @buf: the buffer to extract from 619 * @dstp: the cpumask to set. 620 * 621 * Returns -errno, or 0 for success. 622 */ 623 static inline int cpulist_parse(const char *buf, struct cpumask *dstp) 624 { 625 return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits); 626 } 627 628 /** 629 * cpumask_size - size to allocate for a 'struct cpumask' in bytes 630 * 631 * This will eventually be a runtime variable, depending on nr_cpu_ids. 632 */ 633 static inline size_t cpumask_size(void) 634 { 635 /* FIXME: Once all cpumask assignments are eliminated, this 636 * can be nr_cpumask_bits */ 637 return BITS_TO_LONGS(NR_CPUS) * sizeof(long); 638 } 639 640 /* 641 * cpumask_var_t: struct cpumask for stack usage. 642 * 643 * Oh, the wicked games we play! In order to make kernel coding a 644 * little more difficult, we typedef cpumask_var_t to an array or a 645 * pointer: doing &mask on an array is a noop, so it still works. 646 * 647 * ie. 648 * cpumask_var_t tmpmask; 649 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 650 * return -ENOMEM; 651 * 652 * ... use 'tmpmask' like a normal struct cpumask * ... 653 * 654 * free_cpumask_var(tmpmask); 655 * 656 * 657 * However, one notable exception is there. alloc_cpumask_var() allocates 658 * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has 659 * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t. 660 * 661 * cpumask_var_t tmpmask; 662 * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) 663 * return -ENOMEM; 664 * 665 * var = *tmpmask; 666 * 667 * This code makes NR_CPUS length memcopy and brings to a memory corruption. 668 * cpumask_copy() provide safe copy functionality. 669 * 670 * Note that there is another evil here: If you define a cpumask_var_t 671 * as a percpu variable then the way to obtain the address of the cpumask 672 * structure differently influences what this_cpu_* operation needs to be 673 * used. Please use this_cpu_cpumask_var_t in those cases. The direct use 674 * of this_cpu_ptr() or this_cpu_read() will lead to failures when the 675 * other type of cpumask_var_t implementation is configured. 676 */ 677 #ifdef CONFIG_CPUMASK_OFFSTACK 678 typedef struct cpumask *cpumask_var_t; 679 680 #define this_cpu_cpumask_var_ptr(x) this_cpu_read(x) 681 682 bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); 683 bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags); 684 bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); 685 bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags); 686 void alloc_bootmem_cpumask_var(cpumask_var_t *mask); 687 void free_cpumask_var(cpumask_var_t mask); 688 void free_bootmem_cpumask_var(cpumask_var_t mask); 689 690 #else 691 typedef struct cpumask cpumask_var_t[1]; 692 693 #define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x) 694 695 static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 696 { 697 return true; 698 } 699 700 static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 701 int node) 702 { 703 return true; 704 } 705 706 static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) 707 { 708 cpumask_clear(*mask); 709 return true; 710 } 711 712 static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, 713 int node) 714 { 715 cpumask_clear(*mask); 716 return true; 717 } 718 719 static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask) 720 { 721 } 722 723 static inline void free_cpumask_var(cpumask_var_t mask) 724 { 725 } 726 727 static inline void free_bootmem_cpumask_var(cpumask_var_t mask) 728 { 729 } 730 #endif /* CONFIG_CPUMASK_OFFSTACK */ 731 732 /* It's common to want to use cpu_all_mask in struct member initializers, 733 * so it has to refer to an address rather than a pointer. */ 734 extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS); 735 #define cpu_all_mask to_cpumask(cpu_all_bits) 736 737 /* First bits of cpu_bit_bitmap are in fact unset. */ 738 #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0]) 739 740 #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask) 741 #define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask) 742 #define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask) 743 744 /* Wrappers for arch boot code to manipulate normally-constant masks */ 745 void set_cpu_possible(unsigned int cpu, bool possible); 746 void set_cpu_present(unsigned int cpu, bool present); 747 void set_cpu_online(unsigned int cpu, bool online); 748 void set_cpu_active(unsigned int cpu, bool active); 749 void init_cpu_present(const struct cpumask *src); 750 void init_cpu_possible(const struct cpumask *src); 751 void init_cpu_online(const struct cpumask *src); 752 753 /** 754 * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask * 755 * @bitmap: the bitmap 756 * 757 * There are a few places where cpumask_var_t isn't appropriate and 758 * static cpumasks must be used (eg. very early boot), yet we don't 759 * expose the definition of 'struct cpumask'. 760 * 761 * This does the conversion, and can be used as a constant initializer. 762 */ 763 #define to_cpumask(bitmap) \ 764 ((struct cpumask *)(1 ? (bitmap) \ 765 : (void *)sizeof(__check_is_bitmap(bitmap)))) 766 767 static inline int __check_is_bitmap(const unsigned long *bitmap) 768 { 769 return 1; 770 } 771 772 /* 773 * Special-case data structure for "single bit set only" constant CPU masks. 774 * 775 * We pre-generate all the 64 (or 32) possible bit positions, with enough 776 * padding to the left and the right, and return the constant pointer 777 * appropriately offset. 778 */ 779 extern const unsigned long 780 cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)]; 781 782 static inline const struct cpumask *get_cpu_mask(unsigned int cpu) 783 { 784 const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; 785 p -= cpu / BITS_PER_LONG; 786 return to_cpumask(p); 787 } 788 789 #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu)) 790 791 #if NR_CPUS <= BITS_PER_LONG 792 #define CPU_BITS_ALL \ 793 { \ 794 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ 795 } 796 797 #else /* NR_CPUS > BITS_PER_LONG */ 798 799 #define CPU_BITS_ALL \ 800 { \ 801 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 802 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ 803 } 804 #endif /* NR_CPUS > BITS_PER_LONG */ 805 806 /* 807 * 808 * From here down, all obsolete. Use cpumask_ variants! 809 * 810 */ 811 #ifndef CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS 812 #define cpumask_of_cpu(cpu) (*get_cpu_mask(cpu)) 813 814 #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS) 815 816 #if NR_CPUS <= BITS_PER_LONG 817 818 #define CPU_MASK_ALL \ 819 (cpumask_t) { { \ 820 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ 821 } } 822 823 #else 824 825 #define CPU_MASK_ALL \ 826 (cpumask_t) { { \ 827 [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ 828 [BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD \ 829 } } 830 831 #endif 832 833 #define CPU_MASK_NONE \ 834 (cpumask_t) { { \ 835 [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ 836 } } 837 838 #define CPU_MASK_CPU0 \ 839 (cpumask_t) { { \ 840 [0] = 1UL \ 841 } } 842 843 #if NR_CPUS == 1 844 #define first_cpu(src) ({ (void)(src); 0; }) 845 #define next_cpu(n, src) ({ (void)(src); 1; }) 846 #define any_online_cpu(mask) 0 847 #define for_each_cpu_mask(cpu, mask) \ 848 for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask) 849 #else /* NR_CPUS > 1 */ 850 int __first_cpu(const cpumask_t *srcp); 851 int __next_cpu(int n, const cpumask_t *srcp); 852 853 #define first_cpu(src) __first_cpu(&(src)) 854 #define next_cpu(n, src) __next_cpu((n), &(src)) 855 #define any_online_cpu(mask) cpumask_any_and(&mask, cpu_online_mask) 856 #define for_each_cpu_mask(cpu, mask) \ 857 for ((cpu) = -1; \ 858 (cpu) = next_cpu((cpu), (mask)), \ 859 (cpu) < NR_CPUS; ) 860 #endif /* SMP */ 861 862 #if NR_CPUS <= 64 863 864 #define for_each_cpu_mask_nr(cpu, mask) for_each_cpu_mask(cpu, mask) 865 866 #else /* NR_CPUS > 64 */ 867 868 int __next_cpu_nr(int n, const cpumask_t *srcp); 869 #define for_each_cpu_mask_nr(cpu, mask) \ 870 for ((cpu) = -1; \ 871 (cpu) = __next_cpu_nr((cpu), &(mask)), \ 872 (cpu) < nr_cpu_ids; ) 873 874 #endif /* NR_CPUS > 64 */ 875 876 #define cpus_addr(src) ((src).bits) 877 878 #define cpu_set(cpu, dst) __cpu_set((cpu), &(dst)) 879 static inline void __cpu_set(int cpu, volatile cpumask_t *dstp) 880 { 881 set_bit(cpu, dstp->bits); 882 } 883 884 #define cpu_clear(cpu, dst) __cpu_clear((cpu), &(dst)) 885 static inline void __cpu_clear(int cpu, volatile cpumask_t *dstp) 886 { 887 clear_bit(cpu, dstp->bits); 888 } 889 890 #define cpus_setall(dst) __cpus_setall(&(dst), NR_CPUS) 891 static inline void __cpus_setall(cpumask_t *dstp, int nbits) 892 { 893 bitmap_fill(dstp->bits, nbits); 894 } 895 896 #define cpus_clear(dst) __cpus_clear(&(dst), NR_CPUS) 897 static inline void __cpus_clear(cpumask_t *dstp, int nbits) 898 { 899 bitmap_zero(dstp->bits, nbits); 900 } 901 902 /* No static inline type checking - see Subtlety (1) above. */ 903 #define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask).bits) 904 905 #define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), &(cpumask)) 906 static inline int __cpu_test_and_set(int cpu, cpumask_t *addr) 907 { 908 return test_and_set_bit(cpu, addr->bits); 909 } 910 911 #define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS) 912 static inline int __cpus_and(cpumask_t *dstp, const cpumask_t *src1p, 913 const cpumask_t *src2p, int nbits) 914 { 915 return bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits); 916 } 917 918 #define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS) 919 static inline void __cpus_or(cpumask_t *dstp, const cpumask_t *src1p, 920 const cpumask_t *src2p, int nbits) 921 { 922 bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits); 923 } 924 925 #define cpus_xor(dst, src1, src2) __cpus_xor(&(dst), &(src1), &(src2), NR_CPUS) 926 static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p, 927 const cpumask_t *src2p, int nbits) 928 { 929 bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits); 930 } 931 932 #define cpus_andnot(dst, src1, src2) \ 933 __cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS) 934 static inline int __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p, 935 const cpumask_t *src2p, int nbits) 936 { 937 return bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits); 938 } 939 940 #define cpus_equal(src1, src2) __cpus_equal(&(src1), &(src2), NR_CPUS) 941 static inline int __cpus_equal(const cpumask_t *src1p, 942 const cpumask_t *src2p, int nbits) 943 { 944 return bitmap_equal(src1p->bits, src2p->bits, nbits); 945 } 946 947 #define cpus_intersects(src1, src2) __cpus_intersects(&(src1), &(src2), NR_CPUS) 948 static inline int __cpus_intersects(const cpumask_t *src1p, 949 const cpumask_t *src2p, int nbits) 950 { 951 return bitmap_intersects(src1p->bits, src2p->bits, nbits); 952 } 953 954 #define cpus_subset(src1, src2) __cpus_subset(&(src1), &(src2), NR_CPUS) 955 static inline int __cpus_subset(const cpumask_t *src1p, 956 const cpumask_t *src2p, int nbits) 957 { 958 return bitmap_subset(src1p->bits, src2p->bits, nbits); 959 } 960 961 #define cpus_empty(src) __cpus_empty(&(src), NR_CPUS) 962 static inline int __cpus_empty(const cpumask_t *srcp, int nbits) 963 { 964 return bitmap_empty(srcp->bits, nbits); 965 } 966 967 #define cpus_weight(cpumask) __cpus_weight(&(cpumask), NR_CPUS) 968 static inline int __cpus_weight(const cpumask_t *srcp, int nbits) 969 { 970 return bitmap_weight(srcp->bits, nbits); 971 } 972 973 #define cpus_shift_left(dst, src, n) \ 974 __cpus_shift_left(&(dst), &(src), (n), NR_CPUS) 975 static inline void __cpus_shift_left(cpumask_t *dstp, 976 const cpumask_t *srcp, int n, int nbits) 977 { 978 bitmap_shift_left(dstp->bits, srcp->bits, n, nbits); 979 } 980 #endif /* !CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS */ 981 982 #endif /* __LINUX_CPUMASK_H */ 983