1 #ifndef __LINUX_PERCPU_H 2 #define __LINUX_PERCPU_H 3 4 #include <linux/preempt.h> 5 #include <linux/smp.h> 6 #include <linux/cpumask.h> 7 #include <linux/pfn.h> 8 #include <linux/init.h> 9 10 #include <asm/percpu.h> 11 12 /* enough to cover all DEFINE_PER_CPUs in modules */ 13 #ifdef CONFIG_MODULES 14 #define PERCPU_MODULE_RESERVE (8 << 10) 15 #else 16 #define PERCPU_MODULE_RESERVE 0 17 #endif 18 19 #ifndef PERCPU_ENOUGH_ROOM 20 #define PERCPU_ENOUGH_ROOM \ 21 (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \ 22 PERCPU_MODULE_RESERVE) 23 #endif 24 25 /* 26 * Must be an lvalue. Since @var must be a simple identifier, 27 * we force a syntax error here if it isn't. 28 */ 29 #define get_cpu_var(var) (*({ \ 30 preempt_disable(); \ 31 &__get_cpu_var(var); })) 32 33 /* 34 * The weird & is necessary because sparse considers (void)(var) to be 35 * a direct dereference of percpu variable (var). 36 */ 37 #define put_cpu_var(var) do { \ 38 (void)&(var); \ 39 preempt_enable(); \ 40 } while (0) 41 42 #define get_cpu_ptr(var) ({ \ 43 preempt_disable(); \ 44 this_cpu_ptr(var); }) 45 46 #define put_cpu_ptr(var) do { \ 47 (void)(var); \ 48 preempt_enable(); \ 49 } while (0) 50 51 /* minimum unit size, also is the maximum supported allocation size */ 52 #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10) 53 54 /* 55 * Percpu allocator can serve percpu allocations before slab is 56 * initialized which allows slab to depend on the percpu allocator. 57 * The following two parameters decide how much resource to 58 * preallocate for this. Keep PERCPU_DYNAMIC_RESERVE equal to or 59 * larger than PERCPU_DYNAMIC_EARLY_SIZE. 60 */ 61 #define PERCPU_DYNAMIC_EARLY_SLOTS 128 62 #define PERCPU_DYNAMIC_EARLY_SIZE (12 << 10) 63 64 /* 65 * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy 66 * back on the first chunk for dynamic percpu allocation if arch is 67 * manually allocating and mapping it for faster access (as a part of 68 * large page mapping for example). 69 * 70 * The following values give between one and two pages of free space 71 * after typical minimal boot (2-way SMP, single disk and NIC) with 72 * both defconfig and a distro config on x86_64 and 32. More 73 * intelligent way to determine this would be nice. 74 */ 75 #if BITS_PER_LONG > 32 76 #define PERCPU_DYNAMIC_RESERVE (20 << 10) 77 #else 78 #define PERCPU_DYNAMIC_RESERVE (12 << 10) 79 #endif 80 81 extern void *pcpu_base_addr; 82 extern const unsigned long *pcpu_unit_offsets; 83 84 struct pcpu_group_info { 85 int nr_units; /* aligned # of units */ 86 unsigned long base_offset; /* base address offset */ 87 unsigned int *cpu_map; /* unit->cpu map, empty 88 * entries contain NR_CPUS */ 89 }; 90 91 struct pcpu_alloc_info { 92 size_t static_size; 93 size_t reserved_size; 94 size_t dyn_size; 95 size_t unit_size; 96 size_t atom_size; 97 size_t alloc_size; 98 size_t __ai_size; /* internal, don't use */ 99 int nr_groups; /* 0 if grouping unnecessary */ 100 struct pcpu_group_info groups[]; 101 }; 102 103 enum pcpu_fc { 104 PCPU_FC_AUTO, 105 PCPU_FC_EMBED, 106 PCPU_FC_PAGE, 107 108 PCPU_FC_NR, 109 }; 110 extern const char *pcpu_fc_names[PCPU_FC_NR]; 111 112 extern enum pcpu_fc pcpu_chosen_fc; 113 114 typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size, 115 size_t align); 116 typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size); 117 typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr); 118 typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to); 119 120 extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups, 121 int nr_units); 122 extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai); 123 124 extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai, 125 void *base_addr); 126 127 #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK 128 extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size, 129 size_t atom_size, 130 pcpu_fc_cpu_distance_fn_t cpu_distance_fn, 131 pcpu_fc_alloc_fn_t alloc_fn, 132 pcpu_fc_free_fn_t free_fn); 133 #endif 134 135 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK 136 extern int __init pcpu_page_first_chunk(size_t reserved_size, 137 pcpu_fc_alloc_fn_t alloc_fn, 138 pcpu_fc_free_fn_t free_fn, 139 pcpu_fc_populate_pte_fn_t populate_pte_fn); 140 #endif 141 142 /* 143 * Use this to get to a cpu's version of the per-cpu object 144 * dynamically allocated. Non-atomic access to the current CPU's 145 * version should probably be combined with get_cpu()/put_cpu(). 146 */ 147 #ifdef CONFIG_SMP 148 #define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu))) 149 #else 150 #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); }) 151 #endif 152 153 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align); 154 extern bool is_kernel_percpu_address(unsigned long addr); 155 156 #if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA) 157 extern void __init setup_per_cpu_areas(void); 158 #endif 159 extern void __init percpu_init_late(void); 160 161 extern void __percpu *__alloc_percpu(size_t size, size_t align); 162 extern void free_percpu(void __percpu *__pdata); 163 extern phys_addr_t per_cpu_ptr_to_phys(void *addr); 164 165 #define alloc_percpu(type) \ 166 (typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type)) 167 168 /* 169 * Optional methods for optimized non-lvalue per-cpu variable access. 170 * 171 * @var can be a percpu variable or a field of it and its size should 172 * equal char, int or long. percpu_read() evaluates to a lvalue and 173 * all others to void. 174 * 175 * These operations are guaranteed to be atomic w.r.t. preemption. 176 * The generic versions use plain get/put_cpu_var(). Archs are 177 * encouraged to implement single-instruction alternatives which don't 178 * require preemption protection. 179 */ 180 #ifndef percpu_read 181 # define percpu_read(var) \ 182 ({ \ 183 typeof(var) *pr_ptr__ = &(var); \ 184 typeof(var) pr_ret__; \ 185 pr_ret__ = get_cpu_var(*pr_ptr__); \ 186 put_cpu_var(*pr_ptr__); \ 187 pr_ret__; \ 188 }) 189 #endif 190 191 #define __percpu_generic_to_op(var, val, op) \ 192 do { \ 193 typeof(var) *pgto_ptr__ = &(var); \ 194 get_cpu_var(*pgto_ptr__) op val; \ 195 put_cpu_var(*pgto_ptr__); \ 196 } while (0) 197 198 #ifndef percpu_write 199 # define percpu_write(var, val) __percpu_generic_to_op(var, (val), =) 200 #endif 201 202 #ifndef percpu_add 203 # define percpu_add(var, val) __percpu_generic_to_op(var, (val), +=) 204 #endif 205 206 #ifndef percpu_sub 207 # define percpu_sub(var, val) __percpu_generic_to_op(var, (val), -=) 208 #endif 209 210 #ifndef percpu_and 211 # define percpu_and(var, val) __percpu_generic_to_op(var, (val), &=) 212 #endif 213 214 #ifndef percpu_or 215 # define percpu_or(var, val) __percpu_generic_to_op(var, (val), |=) 216 #endif 217 218 #ifndef percpu_xor 219 # define percpu_xor(var, val) __percpu_generic_to_op(var, (val), ^=) 220 #endif 221 222 /* 223 * Branching function to split up a function into a set of functions that 224 * are called for different scalar sizes of the objects handled. 225 */ 226 227 extern void __bad_size_call_parameter(void); 228 229 #define __pcpu_size_call_return(stem, variable) \ 230 ({ typeof(variable) pscr_ret__; \ 231 __verify_pcpu_ptr(&(variable)); \ 232 switch(sizeof(variable)) { \ 233 case 1: pscr_ret__ = stem##1(variable);break; \ 234 case 2: pscr_ret__ = stem##2(variable);break; \ 235 case 4: pscr_ret__ = stem##4(variable);break; \ 236 case 8: pscr_ret__ = stem##8(variable);break; \ 237 default: \ 238 __bad_size_call_parameter();break; \ 239 } \ 240 pscr_ret__; \ 241 }) 242 243 #define __pcpu_size_call_return2(stem, variable, ...) \ 244 ({ \ 245 typeof(variable) pscr2_ret__; \ 246 __verify_pcpu_ptr(&(variable)); \ 247 switch(sizeof(variable)) { \ 248 case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \ 249 case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break; \ 250 case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break; \ 251 case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break; \ 252 default: \ 253 __bad_size_call_parameter(); break; \ 254 } \ 255 pscr2_ret__; \ 256 }) 257 258 /* 259 * Special handling for cmpxchg_double. cmpxchg_double is passed two 260 * percpu variables. The first has to be aligned to a double word 261 * boundary and the second has to follow directly thereafter. 262 * We enforce this on all architectures even if they don't support 263 * a double cmpxchg instruction, since it's a cheap requirement, and it 264 * avoids breaking the requirement for architectures with the instruction. 265 */ 266 #define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \ 267 ({ \ 268 bool pdcrb_ret__; \ 269 __verify_pcpu_ptr(&pcp1); \ 270 BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \ 271 VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1))); \ 272 VM_BUG_ON((unsigned long)(&pcp2) != \ 273 (unsigned long)(&pcp1) + sizeof(pcp1)); \ 274 switch(sizeof(pcp1)) { \ 275 case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \ 276 case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \ 277 case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \ 278 case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \ 279 default: \ 280 __bad_size_call_parameter(); break; \ 281 } \ 282 pdcrb_ret__; \ 283 }) 284 285 #define __pcpu_size_call(stem, variable, ...) \ 286 do { \ 287 __verify_pcpu_ptr(&(variable)); \ 288 switch(sizeof(variable)) { \ 289 case 1: stem##1(variable, __VA_ARGS__);break; \ 290 case 2: stem##2(variable, __VA_ARGS__);break; \ 291 case 4: stem##4(variable, __VA_ARGS__);break; \ 292 case 8: stem##8(variable, __VA_ARGS__);break; \ 293 default: \ 294 __bad_size_call_parameter();break; \ 295 } \ 296 } while (0) 297 298 /* 299 * Optimized manipulation for memory allocated through the per cpu 300 * allocator or for addresses of per cpu variables. 301 * 302 * These operation guarantee exclusivity of access for other operations 303 * on the *same* processor. The assumption is that per cpu data is only 304 * accessed by a single processor instance (the current one). 305 * 306 * The first group is used for accesses that must be done in a 307 * preemption safe way since we know that the context is not preempt 308 * safe. Interrupts may occur. If the interrupt modifies the variable 309 * too then RMW actions will not be reliable. 310 * 311 * The arch code can provide optimized functions in two ways: 312 * 313 * 1. Override the function completely. F.e. define this_cpu_add(). 314 * The arch must then ensure that the various scalar format passed 315 * are handled correctly. 316 * 317 * 2. Provide functions for certain scalar sizes. F.e. provide 318 * this_cpu_add_2() to provide per cpu atomic operations for 2 byte 319 * sized RMW actions. If arch code does not provide operations for 320 * a scalar size then the fallback in the generic code will be 321 * used. 322 */ 323 324 #define _this_cpu_generic_read(pcp) \ 325 ({ typeof(pcp) ret__; \ 326 preempt_disable(); \ 327 ret__ = *this_cpu_ptr(&(pcp)); \ 328 preempt_enable(); \ 329 ret__; \ 330 }) 331 332 #ifndef this_cpu_read 333 # ifndef this_cpu_read_1 334 # define this_cpu_read_1(pcp) _this_cpu_generic_read(pcp) 335 # endif 336 # ifndef this_cpu_read_2 337 # define this_cpu_read_2(pcp) _this_cpu_generic_read(pcp) 338 # endif 339 # ifndef this_cpu_read_4 340 # define this_cpu_read_4(pcp) _this_cpu_generic_read(pcp) 341 # endif 342 # ifndef this_cpu_read_8 343 # define this_cpu_read_8(pcp) _this_cpu_generic_read(pcp) 344 # endif 345 # define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp)) 346 #endif 347 348 #define _this_cpu_generic_to_op(pcp, val, op) \ 349 do { \ 350 preempt_disable(); \ 351 *__this_cpu_ptr(&(pcp)) op val; \ 352 preempt_enable(); \ 353 } while (0) 354 355 #ifndef this_cpu_write 356 # ifndef this_cpu_write_1 357 # define this_cpu_write_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), =) 358 # endif 359 # ifndef this_cpu_write_2 360 # define this_cpu_write_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), =) 361 # endif 362 # ifndef this_cpu_write_4 363 # define this_cpu_write_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), =) 364 # endif 365 # ifndef this_cpu_write_8 366 # define this_cpu_write_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), =) 367 # endif 368 # define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val)) 369 #endif 370 371 #ifndef this_cpu_add 372 # ifndef this_cpu_add_1 373 # define this_cpu_add_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=) 374 # endif 375 # ifndef this_cpu_add_2 376 # define this_cpu_add_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=) 377 # endif 378 # ifndef this_cpu_add_4 379 # define this_cpu_add_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=) 380 # endif 381 # ifndef this_cpu_add_8 382 # define this_cpu_add_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=) 383 # endif 384 # define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val)) 385 #endif 386 387 #ifndef this_cpu_sub 388 # define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(val)) 389 #endif 390 391 #ifndef this_cpu_inc 392 # define this_cpu_inc(pcp) this_cpu_add((pcp), 1) 393 #endif 394 395 #ifndef this_cpu_dec 396 # define this_cpu_dec(pcp) this_cpu_sub((pcp), 1) 397 #endif 398 399 #ifndef this_cpu_and 400 # ifndef this_cpu_and_1 401 # define this_cpu_and_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=) 402 # endif 403 # ifndef this_cpu_and_2 404 # define this_cpu_and_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=) 405 # endif 406 # ifndef this_cpu_and_4 407 # define this_cpu_and_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=) 408 # endif 409 # ifndef this_cpu_and_8 410 # define this_cpu_and_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=) 411 # endif 412 # define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val)) 413 #endif 414 415 #ifndef this_cpu_or 416 # ifndef this_cpu_or_1 417 # define this_cpu_or_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=) 418 # endif 419 # ifndef this_cpu_or_2 420 # define this_cpu_or_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=) 421 # endif 422 # ifndef this_cpu_or_4 423 # define this_cpu_or_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=) 424 # endif 425 # ifndef this_cpu_or_8 426 # define this_cpu_or_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=) 427 # endif 428 # define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val)) 429 #endif 430 431 #ifndef this_cpu_xor 432 # ifndef this_cpu_xor_1 433 # define this_cpu_xor_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=) 434 # endif 435 # ifndef this_cpu_xor_2 436 # define this_cpu_xor_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=) 437 # endif 438 # ifndef this_cpu_xor_4 439 # define this_cpu_xor_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=) 440 # endif 441 # ifndef this_cpu_xor_8 442 # define this_cpu_xor_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=) 443 # endif 444 # define this_cpu_xor(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val)) 445 #endif 446 447 #define _this_cpu_generic_add_return(pcp, val) \ 448 ({ \ 449 typeof(pcp) ret__; \ 450 preempt_disable(); \ 451 __this_cpu_add(pcp, val); \ 452 ret__ = __this_cpu_read(pcp); \ 453 preempt_enable(); \ 454 ret__; \ 455 }) 456 457 #ifndef this_cpu_add_return 458 # ifndef this_cpu_add_return_1 459 # define this_cpu_add_return_1(pcp, val) _this_cpu_generic_add_return(pcp, val) 460 # endif 461 # ifndef this_cpu_add_return_2 462 # define this_cpu_add_return_2(pcp, val) _this_cpu_generic_add_return(pcp, val) 463 # endif 464 # ifndef this_cpu_add_return_4 465 # define this_cpu_add_return_4(pcp, val) _this_cpu_generic_add_return(pcp, val) 466 # endif 467 # ifndef this_cpu_add_return_8 468 # define this_cpu_add_return_8(pcp, val) _this_cpu_generic_add_return(pcp, val) 469 # endif 470 # define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val) 471 #endif 472 473 #define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(val)) 474 #define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1) 475 #define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1) 476 477 #define _this_cpu_generic_xchg(pcp, nval) \ 478 ({ typeof(pcp) ret__; \ 479 preempt_disable(); \ 480 ret__ = __this_cpu_read(pcp); \ 481 __this_cpu_write(pcp, nval); \ 482 preempt_enable(); \ 483 ret__; \ 484 }) 485 486 #ifndef this_cpu_xchg 487 # ifndef this_cpu_xchg_1 488 # define this_cpu_xchg_1(pcp, nval) _this_cpu_generic_xchg(pcp, nval) 489 # endif 490 # ifndef this_cpu_xchg_2 491 # define this_cpu_xchg_2(pcp, nval) _this_cpu_generic_xchg(pcp, nval) 492 # endif 493 # ifndef this_cpu_xchg_4 494 # define this_cpu_xchg_4(pcp, nval) _this_cpu_generic_xchg(pcp, nval) 495 # endif 496 # ifndef this_cpu_xchg_8 497 # define this_cpu_xchg_8(pcp, nval) _this_cpu_generic_xchg(pcp, nval) 498 # endif 499 # define this_cpu_xchg(pcp, nval) \ 500 __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval) 501 #endif 502 503 #define _this_cpu_generic_cmpxchg(pcp, oval, nval) \ 504 ({ typeof(pcp) ret__; \ 505 preempt_disable(); \ 506 ret__ = __this_cpu_read(pcp); \ 507 if (ret__ == (oval)) \ 508 __this_cpu_write(pcp, nval); \ 509 preempt_enable(); \ 510 ret__; \ 511 }) 512 513 #ifndef this_cpu_cmpxchg 514 # ifndef this_cpu_cmpxchg_1 515 # define this_cpu_cmpxchg_1(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval) 516 # endif 517 # ifndef this_cpu_cmpxchg_2 518 # define this_cpu_cmpxchg_2(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval) 519 # endif 520 # ifndef this_cpu_cmpxchg_4 521 # define this_cpu_cmpxchg_4(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval) 522 # endif 523 # ifndef this_cpu_cmpxchg_8 524 # define this_cpu_cmpxchg_8(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval) 525 # endif 526 # define this_cpu_cmpxchg(pcp, oval, nval) \ 527 __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval) 528 #endif 529 530 /* 531 * cmpxchg_double replaces two adjacent scalars at once. The first 532 * two parameters are per cpu variables which have to be of the same 533 * size. A truth value is returned to indicate success or failure 534 * (since a double register result is difficult to handle). There is 535 * very limited hardware support for these operations, so only certain 536 * sizes may work. 537 */ 538 #define _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 539 ({ \ 540 int ret__; \ 541 preempt_disable(); \ 542 ret__ = __this_cpu_generic_cmpxchg_double(pcp1, pcp2, \ 543 oval1, oval2, nval1, nval2); \ 544 preempt_enable(); \ 545 ret__; \ 546 }) 547 548 #ifndef this_cpu_cmpxchg_double 549 # ifndef this_cpu_cmpxchg_double_1 550 # define this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 551 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 552 # endif 553 # ifndef this_cpu_cmpxchg_double_2 554 # define this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 555 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 556 # endif 557 # ifndef this_cpu_cmpxchg_double_4 558 # define this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 559 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 560 # endif 561 # ifndef this_cpu_cmpxchg_double_8 562 # define this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 563 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 564 # endif 565 # define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 566 __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) 567 #endif 568 569 /* 570 * Generic percpu operations that do not require preemption handling. 571 * Either we do not care about races or the caller has the 572 * responsibility of handling preemptions issues. Arch code can still 573 * override these instructions since the arch per cpu code may be more 574 * efficient and may actually get race freeness for free (that is the 575 * case for x86 for example). 576 * 577 * If there is no other protection through preempt disable and/or 578 * disabling interupts then one of these RMW operations can show unexpected 579 * behavior because the execution thread was rescheduled on another processor 580 * or an interrupt occurred and the same percpu variable was modified from 581 * the interrupt context. 582 */ 583 #ifndef __this_cpu_read 584 # ifndef __this_cpu_read_1 585 # define __this_cpu_read_1(pcp) (*__this_cpu_ptr(&(pcp))) 586 # endif 587 # ifndef __this_cpu_read_2 588 # define __this_cpu_read_2(pcp) (*__this_cpu_ptr(&(pcp))) 589 # endif 590 # ifndef __this_cpu_read_4 591 # define __this_cpu_read_4(pcp) (*__this_cpu_ptr(&(pcp))) 592 # endif 593 # ifndef __this_cpu_read_8 594 # define __this_cpu_read_8(pcp) (*__this_cpu_ptr(&(pcp))) 595 # endif 596 # define __this_cpu_read(pcp) __pcpu_size_call_return(__this_cpu_read_, (pcp)) 597 #endif 598 599 #define __this_cpu_generic_to_op(pcp, val, op) \ 600 do { \ 601 *__this_cpu_ptr(&(pcp)) op val; \ 602 } while (0) 603 604 #ifndef __this_cpu_write 605 # ifndef __this_cpu_write_1 606 # define __this_cpu_write_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), =) 607 # endif 608 # ifndef __this_cpu_write_2 609 # define __this_cpu_write_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), =) 610 # endif 611 # ifndef __this_cpu_write_4 612 # define __this_cpu_write_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), =) 613 # endif 614 # ifndef __this_cpu_write_8 615 # define __this_cpu_write_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), =) 616 # endif 617 # define __this_cpu_write(pcp, val) __pcpu_size_call(__this_cpu_write_, (pcp), (val)) 618 #endif 619 620 #ifndef __this_cpu_add 621 # ifndef __this_cpu_add_1 622 # define __this_cpu_add_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=) 623 # endif 624 # ifndef __this_cpu_add_2 625 # define __this_cpu_add_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=) 626 # endif 627 # ifndef __this_cpu_add_4 628 # define __this_cpu_add_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=) 629 # endif 630 # ifndef __this_cpu_add_8 631 # define __this_cpu_add_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=) 632 # endif 633 # define __this_cpu_add(pcp, val) __pcpu_size_call(__this_cpu_add_, (pcp), (val)) 634 #endif 635 636 #ifndef __this_cpu_sub 637 # define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(val)) 638 #endif 639 640 #ifndef __this_cpu_inc 641 # define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1) 642 #endif 643 644 #ifndef __this_cpu_dec 645 # define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1) 646 #endif 647 648 #ifndef __this_cpu_and 649 # ifndef __this_cpu_and_1 650 # define __this_cpu_and_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=) 651 # endif 652 # ifndef __this_cpu_and_2 653 # define __this_cpu_and_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=) 654 # endif 655 # ifndef __this_cpu_and_4 656 # define __this_cpu_and_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=) 657 # endif 658 # ifndef __this_cpu_and_8 659 # define __this_cpu_and_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=) 660 # endif 661 # define __this_cpu_and(pcp, val) __pcpu_size_call(__this_cpu_and_, (pcp), (val)) 662 #endif 663 664 #ifndef __this_cpu_or 665 # ifndef __this_cpu_or_1 666 # define __this_cpu_or_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=) 667 # endif 668 # ifndef __this_cpu_or_2 669 # define __this_cpu_or_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=) 670 # endif 671 # ifndef __this_cpu_or_4 672 # define __this_cpu_or_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=) 673 # endif 674 # ifndef __this_cpu_or_8 675 # define __this_cpu_or_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=) 676 # endif 677 # define __this_cpu_or(pcp, val) __pcpu_size_call(__this_cpu_or_, (pcp), (val)) 678 #endif 679 680 #ifndef __this_cpu_xor 681 # ifndef __this_cpu_xor_1 682 # define __this_cpu_xor_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=) 683 # endif 684 # ifndef __this_cpu_xor_2 685 # define __this_cpu_xor_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=) 686 # endif 687 # ifndef __this_cpu_xor_4 688 # define __this_cpu_xor_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=) 689 # endif 690 # ifndef __this_cpu_xor_8 691 # define __this_cpu_xor_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=) 692 # endif 693 # define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val)) 694 #endif 695 696 #define __this_cpu_generic_add_return(pcp, val) \ 697 ({ \ 698 __this_cpu_add(pcp, val); \ 699 __this_cpu_read(pcp); \ 700 }) 701 702 #ifndef __this_cpu_add_return 703 # ifndef __this_cpu_add_return_1 704 # define __this_cpu_add_return_1(pcp, val) __this_cpu_generic_add_return(pcp, val) 705 # endif 706 # ifndef __this_cpu_add_return_2 707 # define __this_cpu_add_return_2(pcp, val) __this_cpu_generic_add_return(pcp, val) 708 # endif 709 # ifndef __this_cpu_add_return_4 710 # define __this_cpu_add_return_4(pcp, val) __this_cpu_generic_add_return(pcp, val) 711 # endif 712 # ifndef __this_cpu_add_return_8 713 # define __this_cpu_add_return_8(pcp, val) __this_cpu_generic_add_return(pcp, val) 714 # endif 715 # define __this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val) 716 #endif 717 718 #define __this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(val)) 719 #define __this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1) 720 #define __this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1) 721 722 #define __this_cpu_generic_xchg(pcp, nval) \ 723 ({ typeof(pcp) ret__; \ 724 ret__ = __this_cpu_read(pcp); \ 725 __this_cpu_write(pcp, nval); \ 726 ret__; \ 727 }) 728 729 #ifndef __this_cpu_xchg 730 # ifndef __this_cpu_xchg_1 731 # define __this_cpu_xchg_1(pcp, nval) __this_cpu_generic_xchg(pcp, nval) 732 # endif 733 # ifndef __this_cpu_xchg_2 734 # define __this_cpu_xchg_2(pcp, nval) __this_cpu_generic_xchg(pcp, nval) 735 # endif 736 # ifndef __this_cpu_xchg_4 737 # define __this_cpu_xchg_4(pcp, nval) __this_cpu_generic_xchg(pcp, nval) 738 # endif 739 # ifndef __this_cpu_xchg_8 740 # define __this_cpu_xchg_8(pcp, nval) __this_cpu_generic_xchg(pcp, nval) 741 # endif 742 # define __this_cpu_xchg(pcp, nval) \ 743 __pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval) 744 #endif 745 746 #define __this_cpu_generic_cmpxchg(pcp, oval, nval) \ 747 ({ \ 748 typeof(pcp) ret__; \ 749 ret__ = __this_cpu_read(pcp); \ 750 if (ret__ == (oval)) \ 751 __this_cpu_write(pcp, nval); \ 752 ret__; \ 753 }) 754 755 #ifndef __this_cpu_cmpxchg 756 # ifndef __this_cpu_cmpxchg_1 757 # define __this_cpu_cmpxchg_1(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval) 758 # endif 759 # ifndef __this_cpu_cmpxchg_2 760 # define __this_cpu_cmpxchg_2(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval) 761 # endif 762 # ifndef __this_cpu_cmpxchg_4 763 # define __this_cpu_cmpxchg_4(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval) 764 # endif 765 # ifndef __this_cpu_cmpxchg_8 766 # define __this_cpu_cmpxchg_8(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval) 767 # endif 768 # define __this_cpu_cmpxchg(pcp, oval, nval) \ 769 __pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval) 770 #endif 771 772 #define __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 773 ({ \ 774 int __ret = 0; \ 775 if (__this_cpu_read(pcp1) == (oval1) && \ 776 __this_cpu_read(pcp2) == (oval2)) { \ 777 __this_cpu_write(pcp1, (nval1)); \ 778 __this_cpu_write(pcp2, (nval2)); \ 779 __ret = 1; \ 780 } \ 781 (__ret); \ 782 }) 783 784 #ifndef __this_cpu_cmpxchg_double 785 # ifndef __this_cpu_cmpxchg_double_1 786 # define __this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 787 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 788 # endif 789 # ifndef __this_cpu_cmpxchg_double_2 790 # define __this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 791 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 792 # endif 793 # ifndef __this_cpu_cmpxchg_double_4 794 # define __this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 795 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 796 # endif 797 # ifndef __this_cpu_cmpxchg_double_8 798 # define __this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 799 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 800 # endif 801 # define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 802 __pcpu_double_call_return_bool(__this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) 803 #endif 804 805 /* 806 * IRQ safe versions of the per cpu RMW operations. Note that these operations 807 * are *not* safe against modification of the same variable from another 808 * processors (which one gets when using regular atomic operations) 809 * They are guaranteed to be atomic vs. local interrupts and 810 * preemption only. 811 */ 812 #define irqsafe_cpu_generic_to_op(pcp, val, op) \ 813 do { \ 814 unsigned long flags; \ 815 local_irq_save(flags); \ 816 *__this_cpu_ptr(&(pcp)) op val; \ 817 local_irq_restore(flags); \ 818 } while (0) 819 820 #ifndef irqsafe_cpu_add 821 # ifndef irqsafe_cpu_add_1 822 # define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=) 823 # endif 824 # ifndef irqsafe_cpu_add_2 825 # define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=) 826 # endif 827 # ifndef irqsafe_cpu_add_4 828 # define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=) 829 # endif 830 # ifndef irqsafe_cpu_add_8 831 # define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=) 832 # endif 833 # define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val)) 834 #endif 835 836 #ifndef irqsafe_cpu_sub 837 # define irqsafe_cpu_sub(pcp, val) irqsafe_cpu_add((pcp), -(val)) 838 #endif 839 840 #ifndef irqsafe_cpu_inc 841 # define irqsafe_cpu_inc(pcp) irqsafe_cpu_add((pcp), 1) 842 #endif 843 844 #ifndef irqsafe_cpu_dec 845 # define irqsafe_cpu_dec(pcp) irqsafe_cpu_sub((pcp), 1) 846 #endif 847 848 #ifndef irqsafe_cpu_and 849 # ifndef irqsafe_cpu_and_1 850 # define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=) 851 # endif 852 # ifndef irqsafe_cpu_and_2 853 # define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=) 854 # endif 855 # ifndef irqsafe_cpu_and_4 856 # define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=) 857 # endif 858 # ifndef irqsafe_cpu_and_8 859 # define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=) 860 # endif 861 # define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val)) 862 #endif 863 864 #ifndef irqsafe_cpu_or 865 # ifndef irqsafe_cpu_or_1 866 # define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=) 867 # endif 868 # ifndef irqsafe_cpu_or_2 869 # define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=) 870 # endif 871 # ifndef irqsafe_cpu_or_4 872 # define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=) 873 # endif 874 # ifndef irqsafe_cpu_or_8 875 # define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=) 876 # endif 877 # define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val)) 878 #endif 879 880 #ifndef irqsafe_cpu_xor 881 # ifndef irqsafe_cpu_xor_1 882 # define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=) 883 # endif 884 # ifndef irqsafe_cpu_xor_2 885 # define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=) 886 # endif 887 # ifndef irqsafe_cpu_xor_4 888 # define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=) 889 # endif 890 # ifndef irqsafe_cpu_xor_8 891 # define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=) 892 # endif 893 # define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val)) 894 #endif 895 896 #define irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) \ 897 ({ \ 898 typeof(pcp) ret__; \ 899 unsigned long flags; \ 900 local_irq_save(flags); \ 901 ret__ = __this_cpu_read(pcp); \ 902 if (ret__ == (oval)) \ 903 __this_cpu_write(pcp, nval); \ 904 local_irq_restore(flags); \ 905 ret__; \ 906 }) 907 908 #ifndef irqsafe_cpu_cmpxchg 909 # ifndef irqsafe_cpu_cmpxchg_1 910 # define irqsafe_cpu_cmpxchg_1(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) 911 # endif 912 # ifndef irqsafe_cpu_cmpxchg_2 913 # define irqsafe_cpu_cmpxchg_2(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) 914 # endif 915 # ifndef irqsafe_cpu_cmpxchg_4 916 # define irqsafe_cpu_cmpxchg_4(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) 917 # endif 918 # ifndef irqsafe_cpu_cmpxchg_8 919 # define irqsafe_cpu_cmpxchg_8(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) 920 # endif 921 # define irqsafe_cpu_cmpxchg(pcp, oval, nval) \ 922 __pcpu_size_call_return2(irqsafe_cpu_cmpxchg_, (pcp), oval, nval) 923 #endif 924 925 #define irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 926 ({ \ 927 int ret__; \ 928 unsigned long flags; \ 929 local_irq_save(flags); \ 930 ret__ = __this_cpu_generic_cmpxchg_double(pcp1, pcp2, \ 931 oval1, oval2, nval1, nval2); \ 932 local_irq_restore(flags); \ 933 ret__; \ 934 }) 935 936 #ifndef irqsafe_cpu_cmpxchg_double 937 # ifndef irqsafe_cpu_cmpxchg_double_1 938 # define irqsafe_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 939 irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 940 # endif 941 # ifndef irqsafe_cpu_cmpxchg_double_2 942 # define irqsafe_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 943 irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 944 # endif 945 # ifndef irqsafe_cpu_cmpxchg_double_4 946 # define irqsafe_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 947 irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 948 # endif 949 # ifndef irqsafe_cpu_cmpxchg_double_8 950 # define irqsafe_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 951 irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 952 # endif 953 # define irqsafe_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 954 __pcpu_double_call_return_bool(irqsafe_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) 955 #endif 956 957 #endif /* __LINUX_PERCPU_H */ 958