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 */ 263 #define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \ 264 ({ \ 265 bool pdcrb_ret__; \ 266 __verify_pcpu_ptr(&pcp1); \ 267 BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \ 268 VM_BUG_ON((unsigned long)(&pcp1) % (2 * sizeof(pcp1))); \ 269 VM_BUG_ON((unsigned long)(&pcp2) != \ 270 (unsigned long)(&pcp1) + sizeof(pcp1)); \ 271 switch(sizeof(pcp1)) { \ 272 case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \ 273 case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \ 274 case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \ 275 case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \ 276 default: \ 277 __bad_size_call_parameter(); break; \ 278 } \ 279 pdcrb_ret__; \ 280 }) 281 282 #define __pcpu_size_call(stem, variable, ...) \ 283 do { \ 284 __verify_pcpu_ptr(&(variable)); \ 285 switch(sizeof(variable)) { \ 286 case 1: stem##1(variable, __VA_ARGS__);break; \ 287 case 2: stem##2(variable, __VA_ARGS__);break; \ 288 case 4: stem##4(variable, __VA_ARGS__);break; \ 289 case 8: stem##8(variable, __VA_ARGS__);break; \ 290 default: \ 291 __bad_size_call_parameter();break; \ 292 } \ 293 } while (0) 294 295 /* 296 * Optimized manipulation for memory allocated through the per cpu 297 * allocator or for addresses of per cpu variables. 298 * 299 * These operation guarantee exclusivity of access for other operations 300 * on the *same* processor. The assumption is that per cpu data is only 301 * accessed by a single processor instance (the current one). 302 * 303 * The first group is used for accesses that must be done in a 304 * preemption safe way since we know that the context is not preempt 305 * safe. Interrupts may occur. If the interrupt modifies the variable 306 * too then RMW actions will not be reliable. 307 * 308 * The arch code can provide optimized functions in two ways: 309 * 310 * 1. Override the function completely. F.e. define this_cpu_add(). 311 * The arch must then ensure that the various scalar format passed 312 * are handled correctly. 313 * 314 * 2. Provide functions for certain scalar sizes. F.e. provide 315 * this_cpu_add_2() to provide per cpu atomic operations for 2 byte 316 * sized RMW actions. If arch code does not provide operations for 317 * a scalar size then the fallback in the generic code will be 318 * used. 319 */ 320 321 #define _this_cpu_generic_read(pcp) \ 322 ({ typeof(pcp) ret__; \ 323 preempt_disable(); \ 324 ret__ = *this_cpu_ptr(&(pcp)); \ 325 preempt_enable(); \ 326 ret__; \ 327 }) 328 329 #ifndef this_cpu_read 330 # ifndef this_cpu_read_1 331 # define this_cpu_read_1(pcp) _this_cpu_generic_read(pcp) 332 # endif 333 # ifndef this_cpu_read_2 334 # define this_cpu_read_2(pcp) _this_cpu_generic_read(pcp) 335 # endif 336 # ifndef this_cpu_read_4 337 # define this_cpu_read_4(pcp) _this_cpu_generic_read(pcp) 338 # endif 339 # ifndef this_cpu_read_8 340 # define this_cpu_read_8(pcp) _this_cpu_generic_read(pcp) 341 # endif 342 # define this_cpu_read(pcp) __pcpu_size_call_return(this_cpu_read_, (pcp)) 343 #endif 344 345 #define _this_cpu_generic_to_op(pcp, val, op) \ 346 do { \ 347 preempt_disable(); \ 348 *__this_cpu_ptr(&(pcp)) op val; \ 349 preempt_enable(); \ 350 } while (0) 351 352 #ifndef this_cpu_write 353 # ifndef this_cpu_write_1 354 # define this_cpu_write_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), =) 355 # endif 356 # ifndef this_cpu_write_2 357 # define this_cpu_write_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), =) 358 # endif 359 # ifndef this_cpu_write_4 360 # define this_cpu_write_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), =) 361 # endif 362 # ifndef this_cpu_write_8 363 # define this_cpu_write_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), =) 364 # endif 365 # define this_cpu_write(pcp, val) __pcpu_size_call(this_cpu_write_, (pcp), (val)) 366 #endif 367 368 #ifndef this_cpu_add 369 # ifndef this_cpu_add_1 370 # define this_cpu_add_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=) 371 # endif 372 # ifndef this_cpu_add_2 373 # define this_cpu_add_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=) 374 # endif 375 # ifndef this_cpu_add_4 376 # define this_cpu_add_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=) 377 # endif 378 # ifndef this_cpu_add_8 379 # define this_cpu_add_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), +=) 380 # endif 381 # define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, (pcp), (val)) 382 #endif 383 384 #ifndef this_cpu_sub 385 # define this_cpu_sub(pcp, val) this_cpu_add((pcp), -(val)) 386 #endif 387 388 #ifndef this_cpu_inc 389 # define this_cpu_inc(pcp) this_cpu_add((pcp), 1) 390 #endif 391 392 #ifndef this_cpu_dec 393 # define this_cpu_dec(pcp) this_cpu_sub((pcp), 1) 394 #endif 395 396 #ifndef this_cpu_and 397 # ifndef this_cpu_and_1 398 # define this_cpu_and_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=) 399 # endif 400 # ifndef this_cpu_and_2 401 # define this_cpu_and_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=) 402 # endif 403 # ifndef this_cpu_and_4 404 # define this_cpu_and_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=) 405 # endif 406 # ifndef this_cpu_and_8 407 # define this_cpu_and_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), &=) 408 # endif 409 # define this_cpu_and(pcp, val) __pcpu_size_call(this_cpu_and_, (pcp), (val)) 410 #endif 411 412 #ifndef this_cpu_or 413 # ifndef this_cpu_or_1 414 # define this_cpu_or_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=) 415 # endif 416 # ifndef this_cpu_or_2 417 # define this_cpu_or_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=) 418 # endif 419 # ifndef this_cpu_or_4 420 # define this_cpu_or_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=) 421 # endif 422 # ifndef this_cpu_or_8 423 # define this_cpu_or_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), |=) 424 # endif 425 # define this_cpu_or(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val)) 426 #endif 427 428 #ifndef this_cpu_xor 429 # ifndef this_cpu_xor_1 430 # define this_cpu_xor_1(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=) 431 # endif 432 # ifndef this_cpu_xor_2 433 # define this_cpu_xor_2(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=) 434 # endif 435 # ifndef this_cpu_xor_4 436 # define this_cpu_xor_4(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=) 437 # endif 438 # ifndef this_cpu_xor_8 439 # define this_cpu_xor_8(pcp, val) _this_cpu_generic_to_op((pcp), (val), ^=) 440 # endif 441 # define this_cpu_xor(pcp, val) __pcpu_size_call(this_cpu_or_, (pcp), (val)) 442 #endif 443 444 #define _this_cpu_generic_add_return(pcp, val) \ 445 ({ \ 446 typeof(pcp) ret__; \ 447 preempt_disable(); \ 448 __this_cpu_add(pcp, val); \ 449 ret__ = __this_cpu_read(pcp); \ 450 preempt_enable(); \ 451 ret__; \ 452 }) 453 454 #ifndef this_cpu_add_return 455 # ifndef this_cpu_add_return_1 456 # define this_cpu_add_return_1(pcp, val) _this_cpu_generic_add_return(pcp, val) 457 # endif 458 # ifndef this_cpu_add_return_2 459 # define this_cpu_add_return_2(pcp, val) _this_cpu_generic_add_return(pcp, val) 460 # endif 461 # ifndef this_cpu_add_return_4 462 # define this_cpu_add_return_4(pcp, val) _this_cpu_generic_add_return(pcp, val) 463 # endif 464 # ifndef this_cpu_add_return_8 465 # define this_cpu_add_return_8(pcp, val) _this_cpu_generic_add_return(pcp, val) 466 # endif 467 # define this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val) 468 #endif 469 470 #define this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(val)) 471 #define this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1) 472 #define this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1) 473 474 #define _this_cpu_generic_xchg(pcp, nval) \ 475 ({ typeof(pcp) ret__; \ 476 preempt_disable(); \ 477 ret__ = __this_cpu_read(pcp); \ 478 __this_cpu_write(pcp, nval); \ 479 preempt_enable(); \ 480 ret__; \ 481 }) 482 483 #ifndef this_cpu_xchg 484 # ifndef this_cpu_xchg_1 485 # define this_cpu_xchg_1(pcp, nval) _this_cpu_generic_xchg(pcp, nval) 486 # endif 487 # ifndef this_cpu_xchg_2 488 # define this_cpu_xchg_2(pcp, nval) _this_cpu_generic_xchg(pcp, nval) 489 # endif 490 # ifndef this_cpu_xchg_4 491 # define this_cpu_xchg_4(pcp, nval) _this_cpu_generic_xchg(pcp, nval) 492 # endif 493 # ifndef this_cpu_xchg_8 494 # define this_cpu_xchg_8(pcp, nval) _this_cpu_generic_xchg(pcp, nval) 495 # endif 496 # define this_cpu_xchg(pcp, nval) \ 497 __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval) 498 #endif 499 500 #define _this_cpu_generic_cmpxchg(pcp, oval, nval) \ 501 ({ typeof(pcp) ret__; \ 502 preempt_disable(); \ 503 ret__ = __this_cpu_read(pcp); \ 504 if (ret__ == (oval)) \ 505 __this_cpu_write(pcp, nval); \ 506 preempt_enable(); \ 507 ret__; \ 508 }) 509 510 #ifndef this_cpu_cmpxchg 511 # ifndef this_cpu_cmpxchg_1 512 # define this_cpu_cmpxchg_1(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval) 513 # endif 514 # ifndef this_cpu_cmpxchg_2 515 # define this_cpu_cmpxchg_2(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval) 516 # endif 517 # ifndef this_cpu_cmpxchg_4 518 # define this_cpu_cmpxchg_4(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval) 519 # endif 520 # ifndef this_cpu_cmpxchg_8 521 # define this_cpu_cmpxchg_8(pcp, oval, nval) _this_cpu_generic_cmpxchg(pcp, oval, nval) 522 # endif 523 # define this_cpu_cmpxchg(pcp, oval, nval) \ 524 __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval) 525 #endif 526 527 /* 528 * cmpxchg_double replaces two adjacent scalars at once. The first 529 * two parameters are per cpu variables which have to be of the same 530 * size. A truth value is returned to indicate success or failure 531 * (since a double register result is difficult to handle). There is 532 * very limited hardware support for these operations, so only certain 533 * sizes may work. 534 */ 535 #define _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 536 ({ \ 537 int ret__; \ 538 preempt_disable(); \ 539 ret__ = __this_cpu_generic_cmpxchg_double(pcp1, pcp2, \ 540 oval1, oval2, nval1, nval2); \ 541 preempt_enable(); \ 542 ret__; \ 543 }) 544 545 #ifndef this_cpu_cmpxchg_double 546 # ifndef this_cpu_cmpxchg_double_1 547 # define this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 548 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 549 # endif 550 # ifndef this_cpu_cmpxchg_double_2 551 # define this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 552 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 553 # endif 554 # ifndef this_cpu_cmpxchg_double_4 555 # define this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 556 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 557 # endif 558 # ifndef this_cpu_cmpxchg_double_8 559 # define this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 560 _this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 561 # endif 562 # define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 563 __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) 564 #endif 565 566 /* 567 * Generic percpu operations that do not require preemption handling. 568 * Either we do not care about races or the caller has the 569 * responsibility of handling preemptions issues. Arch code can still 570 * override these instructions since the arch per cpu code may be more 571 * efficient and may actually get race freeness for free (that is the 572 * case for x86 for example). 573 * 574 * If there is no other protection through preempt disable and/or 575 * disabling interupts then one of these RMW operations can show unexpected 576 * behavior because the execution thread was rescheduled on another processor 577 * or an interrupt occurred and the same percpu variable was modified from 578 * the interrupt context. 579 */ 580 #ifndef __this_cpu_read 581 # ifndef __this_cpu_read_1 582 # define __this_cpu_read_1(pcp) (*__this_cpu_ptr(&(pcp))) 583 # endif 584 # ifndef __this_cpu_read_2 585 # define __this_cpu_read_2(pcp) (*__this_cpu_ptr(&(pcp))) 586 # endif 587 # ifndef __this_cpu_read_4 588 # define __this_cpu_read_4(pcp) (*__this_cpu_ptr(&(pcp))) 589 # endif 590 # ifndef __this_cpu_read_8 591 # define __this_cpu_read_8(pcp) (*__this_cpu_ptr(&(pcp))) 592 # endif 593 # define __this_cpu_read(pcp) __pcpu_size_call_return(__this_cpu_read_, (pcp)) 594 #endif 595 596 #define __this_cpu_generic_to_op(pcp, val, op) \ 597 do { \ 598 *__this_cpu_ptr(&(pcp)) op val; \ 599 } while (0) 600 601 #ifndef __this_cpu_write 602 # ifndef __this_cpu_write_1 603 # define __this_cpu_write_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), =) 604 # endif 605 # ifndef __this_cpu_write_2 606 # define __this_cpu_write_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), =) 607 # endif 608 # ifndef __this_cpu_write_4 609 # define __this_cpu_write_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), =) 610 # endif 611 # ifndef __this_cpu_write_8 612 # define __this_cpu_write_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), =) 613 # endif 614 # define __this_cpu_write(pcp, val) __pcpu_size_call(__this_cpu_write_, (pcp), (val)) 615 #endif 616 617 #ifndef __this_cpu_add 618 # ifndef __this_cpu_add_1 619 # define __this_cpu_add_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=) 620 # endif 621 # ifndef __this_cpu_add_2 622 # define __this_cpu_add_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=) 623 # endif 624 # ifndef __this_cpu_add_4 625 # define __this_cpu_add_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=) 626 # endif 627 # ifndef __this_cpu_add_8 628 # define __this_cpu_add_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), +=) 629 # endif 630 # define __this_cpu_add(pcp, val) __pcpu_size_call(__this_cpu_add_, (pcp), (val)) 631 #endif 632 633 #ifndef __this_cpu_sub 634 # define __this_cpu_sub(pcp, val) __this_cpu_add((pcp), -(val)) 635 #endif 636 637 #ifndef __this_cpu_inc 638 # define __this_cpu_inc(pcp) __this_cpu_add((pcp), 1) 639 #endif 640 641 #ifndef __this_cpu_dec 642 # define __this_cpu_dec(pcp) __this_cpu_sub((pcp), 1) 643 #endif 644 645 #ifndef __this_cpu_and 646 # ifndef __this_cpu_and_1 647 # define __this_cpu_and_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=) 648 # endif 649 # ifndef __this_cpu_and_2 650 # define __this_cpu_and_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=) 651 # endif 652 # ifndef __this_cpu_and_4 653 # define __this_cpu_and_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=) 654 # endif 655 # ifndef __this_cpu_and_8 656 # define __this_cpu_and_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), &=) 657 # endif 658 # define __this_cpu_and(pcp, val) __pcpu_size_call(__this_cpu_and_, (pcp), (val)) 659 #endif 660 661 #ifndef __this_cpu_or 662 # ifndef __this_cpu_or_1 663 # define __this_cpu_or_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=) 664 # endif 665 # ifndef __this_cpu_or_2 666 # define __this_cpu_or_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=) 667 # endif 668 # ifndef __this_cpu_or_4 669 # define __this_cpu_or_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=) 670 # endif 671 # ifndef __this_cpu_or_8 672 # define __this_cpu_or_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), |=) 673 # endif 674 # define __this_cpu_or(pcp, val) __pcpu_size_call(__this_cpu_or_, (pcp), (val)) 675 #endif 676 677 #ifndef __this_cpu_xor 678 # ifndef __this_cpu_xor_1 679 # define __this_cpu_xor_1(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=) 680 # endif 681 # ifndef __this_cpu_xor_2 682 # define __this_cpu_xor_2(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=) 683 # endif 684 # ifndef __this_cpu_xor_4 685 # define __this_cpu_xor_4(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=) 686 # endif 687 # ifndef __this_cpu_xor_8 688 # define __this_cpu_xor_8(pcp, val) __this_cpu_generic_to_op((pcp), (val), ^=) 689 # endif 690 # define __this_cpu_xor(pcp, val) __pcpu_size_call(__this_cpu_xor_, (pcp), (val)) 691 #endif 692 693 #define __this_cpu_generic_add_return(pcp, val) \ 694 ({ \ 695 __this_cpu_add(pcp, val); \ 696 __this_cpu_read(pcp); \ 697 }) 698 699 #ifndef __this_cpu_add_return 700 # ifndef __this_cpu_add_return_1 701 # define __this_cpu_add_return_1(pcp, val) __this_cpu_generic_add_return(pcp, val) 702 # endif 703 # ifndef __this_cpu_add_return_2 704 # define __this_cpu_add_return_2(pcp, val) __this_cpu_generic_add_return(pcp, val) 705 # endif 706 # ifndef __this_cpu_add_return_4 707 # define __this_cpu_add_return_4(pcp, val) __this_cpu_generic_add_return(pcp, val) 708 # endif 709 # ifndef __this_cpu_add_return_8 710 # define __this_cpu_add_return_8(pcp, val) __this_cpu_generic_add_return(pcp, val) 711 # endif 712 # define __this_cpu_add_return(pcp, val) __pcpu_size_call_return2(this_cpu_add_return_, pcp, val) 713 #endif 714 715 #define __this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(val)) 716 #define __this_cpu_inc_return(pcp) this_cpu_add_return(pcp, 1) 717 #define __this_cpu_dec_return(pcp) this_cpu_add_return(pcp, -1) 718 719 #define __this_cpu_generic_xchg(pcp, nval) \ 720 ({ typeof(pcp) ret__; \ 721 ret__ = __this_cpu_read(pcp); \ 722 __this_cpu_write(pcp, nval); \ 723 ret__; \ 724 }) 725 726 #ifndef __this_cpu_xchg 727 # ifndef __this_cpu_xchg_1 728 # define __this_cpu_xchg_1(pcp, nval) __this_cpu_generic_xchg(pcp, nval) 729 # endif 730 # ifndef __this_cpu_xchg_2 731 # define __this_cpu_xchg_2(pcp, nval) __this_cpu_generic_xchg(pcp, nval) 732 # endif 733 # ifndef __this_cpu_xchg_4 734 # define __this_cpu_xchg_4(pcp, nval) __this_cpu_generic_xchg(pcp, nval) 735 # endif 736 # ifndef __this_cpu_xchg_8 737 # define __this_cpu_xchg_8(pcp, nval) __this_cpu_generic_xchg(pcp, nval) 738 # endif 739 # define __this_cpu_xchg(pcp, nval) \ 740 __pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval) 741 #endif 742 743 #define __this_cpu_generic_cmpxchg(pcp, oval, nval) \ 744 ({ \ 745 typeof(pcp) ret__; \ 746 ret__ = __this_cpu_read(pcp); \ 747 if (ret__ == (oval)) \ 748 __this_cpu_write(pcp, nval); \ 749 ret__; \ 750 }) 751 752 #ifndef __this_cpu_cmpxchg 753 # ifndef __this_cpu_cmpxchg_1 754 # define __this_cpu_cmpxchg_1(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval) 755 # endif 756 # ifndef __this_cpu_cmpxchg_2 757 # define __this_cpu_cmpxchg_2(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval) 758 # endif 759 # ifndef __this_cpu_cmpxchg_4 760 # define __this_cpu_cmpxchg_4(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval) 761 # endif 762 # ifndef __this_cpu_cmpxchg_8 763 # define __this_cpu_cmpxchg_8(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval) 764 # endif 765 # define __this_cpu_cmpxchg(pcp, oval, nval) \ 766 __pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval) 767 #endif 768 769 #define __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 770 ({ \ 771 int __ret = 0; \ 772 if (__this_cpu_read(pcp1) == (oval1) && \ 773 __this_cpu_read(pcp2) == (oval2)) { \ 774 __this_cpu_write(pcp1, (nval1)); \ 775 __this_cpu_write(pcp2, (nval2)); \ 776 __ret = 1; \ 777 } \ 778 (__ret); \ 779 }) 780 781 #ifndef __this_cpu_cmpxchg_double 782 # ifndef __this_cpu_cmpxchg_double_1 783 # define __this_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 784 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 785 # endif 786 # ifndef __this_cpu_cmpxchg_double_2 787 # define __this_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 788 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 789 # endif 790 # ifndef __this_cpu_cmpxchg_double_4 791 # define __this_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 792 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 793 # endif 794 # ifndef __this_cpu_cmpxchg_double_8 795 # define __this_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 796 __this_cpu_generic_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 797 # endif 798 # define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 799 __pcpu_double_call_return_bool(__this_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) 800 #endif 801 802 /* 803 * IRQ safe versions of the per cpu RMW operations. Note that these operations 804 * are *not* safe against modification of the same variable from another 805 * processors (which one gets when using regular atomic operations) 806 * They are guaranteed to be atomic vs. local interrupts and 807 * preemption only. 808 */ 809 #define irqsafe_cpu_generic_to_op(pcp, val, op) \ 810 do { \ 811 unsigned long flags; \ 812 local_irq_save(flags); \ 813 *__this_cpu_ptr(&(pcp)) op val; \ 814 local_irq_restore(flags); \ 815 } while (0) 816 817 #ifndef irqsafe_cpu_add 818 # ifndef irqsafe_cpu_add_1 819 # define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=) 820 # endif 821 # ifndef irqsafe_cpu_add_2 822 # define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=) 823 # endif 824 # ifndef irqsafe_cpu_add_4 825 # define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=) 826 # endif 827 # ifndef irqsafe_cpu_add_8 828 # define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=) 829 # endif 830 # define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val)) 831 #endif 832 833 #ifndef irqsafe_cpu_sub 834 # define irqsafe_cpu_sub(pcp, val) irqsafe_cpu_add((pcp), -(val)) 835 #endif 836 837 #ifndef irqsafe_cpu_inc 838 # define irqsafe_cpu_inc(pcp) irqsafe_cpu_add((pcp), 1) 839 #endif 840 841 #ifndef irqsafe_cpu_dec 842 # define irqsafe_cpu_dec(pcp) irqsafe_cpu_sub((pcp), 1) 843 #endif 844 845 #ifndef irqsafe_cpu_and 846 # ifndef irqsafe_cpu_and_1 847 # define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=) 848 # endif 849 # ifndef irqsafe_cpu_and_2 850 # define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=) 851 # endif 852 # ifndef irqsafe_cpu_and_4 853 # define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=) 854 # endif 855 # ifndef irqsafe_cpu_and_8 856 # define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=) 857 # endif 858 # define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val)) 859 #endif 860 861 #ifndef irqsafe_cpu_or 862 # ifndef irqsafe_cpu_or_1 863 # define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=) 864 # endif 865 # ifndef irqsafe_cpu_or_2 866 # define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=) 867 # endif 868 # ifndef irqsafe_cpu_or_4 869 # define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=) 870 # endif 871 # ifndef irqsafe_cpu_or_8 872 # define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=) 873 # endif 874 # define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val)) 875 #endif 876 877 #ifndef irqsafe_cpu_xor 878 # ifndef irqsafe_cpu_xor_1 879 # define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=) 880 # endif 881 # ifndef irqsafe_cpu_xor_2 882 # define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=) 883 # endif 884 # ifndef irqsafe_cpu_xor_4 885 # define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=) 886 # endif 887 # ifndef irqsafe_cpu_xor_8 888 # define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=) 889 # endif 890 # define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val)) 891 #endif 892 893 #define irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) \ 894 ({ \ 895 typeof(pcp) ret__; \ 896 unsigned long flags; \ 897 local_irq_save(flags); \ 898 ret__ = __this_cpu_read(pcp); \ 899 if (ret__ == (oval)) \ 900 __this_cpu_write(pcp, nval); \ 901 local_irq_restore(flags); \ 902 ret__; \ 903 }) 904 905 #ifndef irqsafe_cpu_cmpxchg 906 # ifndef irqsafe_cpu_cmpxchg_1 907 # define irqsafe_cpu_cmpxchg_1(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) 908 # endif 909 # ifndef irqsafe_cpu_cmpxchg_2 910 # define irqsafe_cpu_cmpxchg_2(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) 911 # endif 912 # ifndef irqsafe_cpu_cmpxchg_4 913 # define irqsafe_cpu_cmpxchg_4(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) 914 # endif 915 # ifndef irqsafe_cpu_cmpxchg_8 916 # define irqsafe_cpu_cmpxchg_8(pcp, oval, nval) irqsafe_cpu_generic_cmpxchg(pcp, oval, nval) 917 # endif 918 # define irqsafe_cpu_cmpxchg(pcp, oval, nval) \ 919 __pcpu_size_call_return2(irqsafe_cpu_cmpxchg_, (pcp), oval, nval) 920 #endif 921 922 #define irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 923 ({ \ 924 int ret__; \ 925 unsigned long flags; \ 926 local_irq_save(flags); \ 927 ret__ = __this_cpu_generic_cmpxchg_double(pcp1, pcp2, \ 928 oval1, oval2, nval1, nval2); \ 929 local_irq_restore(flags); \ 930 ret__; \ 931 }) 932 933 #ifndef irqsafe_cpu_cmpxchg_double 934 # ifndef irqsafe_cpu_cmpxchg_double_1 935 # define irqsafe_cpu_cmpxchg_double_1(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 936 irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 937 # endif 938 # ifndef irqsafe_cpu_cmpxchg_double_2 939 # define irqsafe_cpu_cmpxchg_double_2(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 940 irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 941 # endif 942 # ifndef irqsafe_cpu_cmpxchg_double_4 943 # define irqsafe_cpu_cmpxchg_double_4(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 944 irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 945 # endif 946 # ifndef irqsafe_cpu_cmpxchg_double_8 947 # define irqsafe_cpu_cmpxchg_double_8(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 948 irqsafe_generic_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) 949 # endif 950 # define irqsafe_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ 951 __pcpu_double_call_return_bool(irqsafe_cpu_cmpxchg_double_, (pcp1), (pcp2), (oval1), (oval2), (nval1), (nval2)) 952 #endif 953 954 #endif /* __LINUX_PERCPU_H */ 955