1#ifndef _ASM_X86_PERCPU_H 2#define _ASM_X86_PERCPU_H 3 4#ifdef CONFIG_X86_64 5#define __percpu_seg gs 6#define __percpu_mov_op movq 7#else 8#define __percpu_seg fs 9#define __percpu_mov_op movl 10#endif 11 12#ifdef __ASSEMBLY__ 13 14/* 15 * PER_CPU finds an address of a per-cpu variable. 16 * 17 * Args: 18 * var - variable name 19 * reg - 32bit register 20 * 21 * The resulting address is stored in the "reg" argument. 22 * 23 * Example: 24 * PER_CPU(cpu_gdt_descr, %ebx) 25 */ 26#ifdef CONFIG_SMP 27#define PER_CPU(var, reg) \ 28 __percpu_mov_op %__percpu_seg:this_cpu_off, reg; \ 29 lea var(reg), reg 30#define PER_CPU_VAR(var) %__percpu_seg:var 31#else /* ! SMP */ 32#define PER_CPU(var, reg) __percpu_mov_op $var, reg 33#define PER_CPU_VAR(var) var 34#endif /* SMP */ 35 36#ifdef CONFIG_X86_64_SMP 37#define INIT_PER_CPU_VAR(var) init_per_cpu__##var 38#else 39#define INIT_PER_CPU_VAR(var) var 40#endif 41 42#else /* ...!ASSEMBLY */ 43 44#include <linux/kernel.h> 45#include <linux/stringify.h> 46 47#ifdef CONFIG_SMP 48#define __percpu_prefix "%%"__stringify(__percpu_seg)":" 49#define __my_cpu_offset percpu_read(this_cpu_off) 50 51/* 52 * Compared to the generic __my_cpu_offset version, the following 53 * saves one instruction and avoids clobbering a temp register. 54 */ 55#define __this_cpu_ptr(ptr) \ 56({ \ 57 unsigned long tcp_ptr__; \ 58 __verify_pcpu_ptr(ptr); \ 59 asm volatile("add " __percpu_arg(1) ", %0" \ 60 : "=r" (tcp_ptr__) \ 61 : "m" (this_cpu_off), "0" (ptr)); \ 62 (typeof(*(ptr)) __kernel __force *)tcp_ptr__; \ 63}) 64#else 65#define __percpu_prefix "" 66#endif 67 68#define __percpu_arg(x) __percpu_prefix "%P" #x 69 70/* 71 * Initialized pointers to per-cpu variables needed for the boot 72 * processor need to use these macros to get the proper address 73 * offset from __per_cpu_load on SMP. 74 * 75 * There also must be an entry in vmlinux_64.lds.S 76 */ 77#define DECLARE_INIT_PER_CPU(var) \ 78 extern typeof(var) init_per_cpu_var(var) 79 80#ifdef CONFIG_X86_64_SMP 81#define init_per_cpu_var(var) init_per_cpu__##var 82#else 83#define init_per_cpu_var(var) var 84#endif 85 86/* For arch-specific code, we can use direct single-insn ops (they 87 * don't give an lvalue though). */ 88extern void __bad_percpu_size(void); 89 90#define percpu_to_op(op, var, val) \ 91do { \ 92 typedef typeof(var) pto_T__; \ 93 if (0) { \ 94 pto_T__ pto_tmp__; \ 95 pto_tmp__ = (val); \ 96 (void)pto_tmp__; \ 97 } \ 98 switch (sizeof(var)) { \ 99 case 1: \ 100 asm(op "b %1,"__percpu_arg(0) \ 101 : "+m" (var) \ 102 : "qi" ((pto_T__)(val))); \ 103 break; \ 104 case 2: \ 105 asm(op "w %1,"__percpu_arg(0) \ 106 : "+m" (var) \ 107 : "ri" ((pto_T__)(val))); \ 108 break; \ 109 case 4: \ 110 asm(op "l %1,"__percpu_arg(0) \ 111 : "+m" (var) \ 112 : "ri" ((pto_T__)(val))); \ 113 break; \ 114 case 8: \ 115 asm(op "q %1,"__percpu_arg(0) \ 116 : "+m" (var) \ 117 : "re" ((pto_T__)(val))); \ 118 break; \ 119 default: __bad_percpu_size(); \ 120 } \ 121} while (0) 122 123/* 124 * Generate a percpu add to memory instruction and optimize code 125 * if one is added or subtracted. 126 */ 127#define percpu_add_op(var, val) \ 128do { \ 129 typedef typeof(var) pao_T__; \ 130 const int pao_ID__ = (__builtin_constant_p(val) && \ 131 ((val) == 1 || (val) == -1)) ? (val) : 0; \ 132 if (0) { \ 133 pao_T__ pao_tmp__; \ 134 pao_tmp__ = (val); \ 135 (void)pao_tmp__; \ 136 } \ 137 switch (sizeof(var)) { \ 138 case 1: \ 139 if (pao_ID__ == 1) \ 140 asm("incb "__percpu_arg(0) : "+m" (var)); \ 141 else if (pao_ID__ == -1) \ 142 asm("decb "__percpu_arg(0) : "+m" (var)); \ 143 else \ 144 asm("addb %1, "__percpu_arg(0) \ 145 : "+m" (var) \ 146 : "qi" ((pao_T__)(val))); \ 147 break; \ 148 case 2: \ 149 if (pao_ID__ == 1) \ 150 asm("incw "__percpu_arg(0) : "+m" (var)); \ 151 else if (pao_ID__ == -1) \ 152 asm("decw "__percpu_arg(0) : "+m" (var)); \ 153 else \ 154 asm("addw %1, "__percpu_arg(0) \ 155 : "+m" (var) \ 156 : "ri" ((pao_T__)(val))); \ 157 break; \ 158 case 4: \ 159 if (pao_ID__ == 1) \ 160 asm("incl "__percpu_arg(0) : "+m" (var)); \ 161 else if (pao_ID__ == -1) \ 162 asm("decl "__percpu_arg(0) : "+m" (var)); \ 163 else \ 164 asm("addl %1, "__percpu_arg(0) \ 165 : "+m" (var) \ 166 : "ri" ((pao_T__)(val))); \ 167 break; \ 168 case 8: \ 169 if (pao_ID__ == 1) \ 170 asm("incq "__percpu_arg(0) : "+m" (var)); \ 171 else if (pao_ID__ == -1) \ 172 asm("decq "__percpu_arg(0) : "+m" (var)); \ 173 else \ 174 asm("addq %1, "__percpu_arg(0) \ 175 : "+m" (var) \ 176 : "re" ((pao_T__)(val))); \ 177 break; \ 178 default: __bad_percpu_size(); \ 179 } \ 180} while (0) 181 182#define percpu_from_op(op, var, constraint) \ 183({ \ 184 typeof(var) pfo_ret__; \ 185 switch (sizeof(var)) { \ 186 case 1: \ 187 asm(op "b "__percpu_arg(1)",%0" \ 188 : "=q" (pfo_ret__) \ 189 : constraint); \ 190 break; \ 191 case 2: \ 192 asm(op "w "__percpu_arg(1)",%0" \ 193 : "=r" (pfo_ret__) \ 194 : constraint); \ 195 break; \ 196 case 4: \ 197 asm(op "l "__percpu_arg(1)",%0" \ 198 : "=r" (pfo_ret__) \ 199 : constraint); \ 200 break; \ 201 case 8: \ 202 asm(op "q "__percpu_arg(1)",%0" \ 203 : "=r" (pfo_ret__) \ 204 : constraint); \ 205 break; \ 206 default: __bad_percpu_size(); \ 207 } \ 208 pfo_ret__; \ 209}) 210 211#define percpu_unary_op(op, var) \ 212({ \ 213 switch (sizeof(var)) { \ 214 case 1: \ 215 asm(op "b "__percpu_arg(0) \ 216 : "+m" (var)); \ 217 break; \ 218 case 2: \ 219 asm(op "w "__percpu_arg(0) \ 220 : "+m" (var)); \ 221 break; \ 222 case 4: \ 223 asm(op "l "__percpu_arg(0) \ 224 : "+m" (var)); \ 225 break; \ 226 case 8: \ 227 asm(op "q "__percpu_arg(0) \ 228 : "+m" (var)); \ 229 break; \ 230 default: __bad_percpu_size(); \ 231 } \ 232}) 233 234/* 235 * Add return operation 236 */ 237#define percpu_add_return_op(var, val) \ 238({ \ 239 typeof(var) paro_ret__ = val; \ 240 switch (sizeof(var)) { \ 241 case 1: \ 242 asm("xaddb %0, "__percpu_arg(1) \ 243 : "+q" (paro_ret__), "+m" (var) \ 244 : : "memory"); \ 245 break; \ 246 case 2: \ 247 asm("xaddw %0, "__percpu_arg(1) \ 248 : "+r" (paro_ret__), "+m" (var) \ 249 : : "memory"); \ 250 break; \ 251 case 4: \ 252 asm("xaddl %0, "__percpu_arg(1) \ 253 : "+r" (paro_ret__), "+m" (var) \ 254 : : "memory"); \ 255 break; \ 256 case 8: \ 257 asm("xaddq %0, "__percpu_arg(1) \ 258 : "+re" (paro_ret__), "+m" (var) \ 259 : : "memory"); \ 260 break; \ 261 default: __bad_percpu_size(); \ 262 } \ 263 paro_ret__ += val; \ 264 paro_ret__; \ 265}) 266 267/* 268 * xchg is implemented using cmpxchg without a lock prefix. xchg is 269 * expensive due to the implied lock prefix. The processor cannot prefetch 270 * cachelines if xchg is used. 271 */ 272#define percpu_xchg_op(var, nval) \ 273({ \ 274 typeof(var) pxo_ret__; \ 275 typeof(var) pxo_new__ = (nval); \ 276 switch (sizeof(var)) { \ 277 case 1: \ 278 asm("\n\tmov "__percpu_arg(1)",%%al" \ 279 "\n1:\tcmpxchgb %2, "__percpu_arg(1) \ 280 "\n\tjnz 1b" \ 281 : "=&a" (pxo_ret__), "+m" (var) \ 282 : "q" (pxo_new__) \ 283 : "memory"); \ 284 break; \ 285 case 2: \ 286 asm("\n\tmov "__percpu_arg(1)",%%ax" \ 287 "\n1:\tcmpxchgw %2, "__percpu_arg(1) \ 288 "\n\tjnz 1b" \ 289 : "=&a" (pxo_ret__), "+m" (var) \ 290 : "r" (pxo_new__) \ 291 : "memory"); \ 292 break; \ 293 case 4: \ 294 asm("\n\tmov "__percpu_arg(1)",%%eax" \ 295 "\n1:\tcmpxchgl %2, "__percpu_arg(1) \ 296 "\n\tjnz 1b" \ 297 : "=&a" (pxo_ret__), "+m" (var) \ 298 : "r" (pxo_new__) \ 299 : "memory"); \ 300 break; \ 301 case 8: \ 302 asm("\n\tmov "__percpu_arg(1)",%%rax" \ 303 "\n1:\tcmpxchgq %2, "__percpu_arg(1) \ 304 "\n\tjnz 1b" \ 305 : "=&a" (pxo_ret__), "+m" (var) \ 306 : "r" (pxo_new__) \ 307 : "memory"); \ 308 break; \ 309 default: __bad_percpu_size(); \ 310 } \ 311 pxo_ret__; \ 312}) 313 314/* 315 * cmpxchg has no such implied lock semantics as a result it is much 316 * more efficient for cpu local operations. 317 */ 318#define percpu_cmpxchg_op(var, oval, nval) \ 319({ \ 320 typeof(var) pco_ret__; \ 321 typeof(var) pco_old__ = (oval); \ 322 typeof(var) pco_new__ = (nval); \ 323 switch (sizeof(var)) { \ 324 case 1: \ 325 asm("cmpxchgb %2, "__percpu_arg(1) \ 326 : "=a" (pco_ret__), "+m" (var) \ 327 : "q" (pco_new__), "0" (pco_old__) \ 328 : "memory"); \ 329 break; \ 330 case 2: \ 331 asm("cmpxchgw %2, "__percpu_arg(1) \ 332 : "=a" (pco_ret__), "+m" (var) \ 333 : "r" (pco_new__), "0" (pco_old__) \ 334 : "memory"); \ 335 break; \ 336 case 4: \ 337 asm("cmpxchgl %2, "__percpu_arg(1) \ 338 : "=a" (pco_ret__), "+m" (var) \ 339 : "r" (pco_new__), "0" (pco_old__) \ 340 : "memory"); \ 341 break; \ 342 case 8: \ 343 asm("cmpxchgq %2, "__percpu_arg(1) \ 344 : "=a" (pco_ret__), "+m" (var) \ 345 : "r" (pco_new__), "0" (pco_old__) \ 346 : "memory"); \ 347 break; \ 348 default: __bad_percpu_size(); \ 349 } \ 350 pco_ret__; \ 351}) 352 353/* 354 * percpu_read() makes gcc load the percpu variable every time it is 355 * accessed while percpu_read_stable() allows the value to be cached. 356 * percpu_read_stable() is more efficient and can be used if its value 357 * is guaranteed to be valid across cpus. The current users include 358 * get_current() and get_thread_info() both of which are actually 359 * per-thread variables implemented as per-cpu variables and thus 360 * stable for the duration of the respective task. 361 */ 362#define percpu_read(var) percpu_from_op("mov", var, "m" (var)) 363#define percpu_read_stable(var) percpu_from_op("mov", var, "p" (&(var))) 364#define percpu_write(var, val) percpu_to_op("mov", var, val) 365#define percpu_add(var, val) percpu_add_op(var, val) 366#define percpu_sub(var, val) percpu_add_op(var, -(val)) 367#define percpu_and(var, val) percpu_to_op("and", var, val) 368#define percpu_or(var, val) percpu_to_op("or", var, val) 369#define percpu_xor(var, val) percpu_to_op("xor", var, val) 370#define percpu_inc(var) percpu_unary_op("inc", var) 371 372#define __this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 373#define __this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 374#define __this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 375 376#define __this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val) 377#define __this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val) 378#define __this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val) 379#define __this_cpu_add_1(pcp, val) percpu_add_op((pcp), val) 380#define __this_cpu_add_2(pcp, val) percpu_add_op((pcp), val) 381#define __this_cpu_add_4(pcp, val) percpu_add_op((pcp), val) 382#define __this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val) 383#define __this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val) 384#define __this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val) 385#define __this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val) 386#define __this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val) 387#define __this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val) 388#define __this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val) 389#define __this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val) 390#define __this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val) 391#define __this_cpu_xchg_1(pcp, val) percpu_xchg_op(pcp, val) 392#define __this_cpu_xchg_2(pcp, val) percpu_xchg_op(pcp, val) 393#define __this_cpu_xchg_4(pcp, val) percpu_xchg_op(pcp, val) 394 395#define this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 396#define this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 397#define this_cpu_read_4(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 398#define this_cpu_write_1(pcp, val) percpu_to_op("mov", (pcp), val) 399#define this_cpu_write_2(pcp, val) percpu_to_op("mov", (pcp), val) 400#define this_cpu_write_4(pcp, val) percpu_to_op("mov", (pcp), val) 401#define this_cpu_add_1(pcp, val) percpu_add_op((pcp), val) 402#define this_cpu_add_2(pcp, val) percpu_add_op((pcp), val) 403#define this_cpu_add_4(pcp, val) percpu_add_op((pcp), val) 404#define this_cpu_and_1(pcp, val) percpu_to_op("and", (pcp), val) 405#define this_cpu_and_2(pcp, val) percpu_to_op("and", (pcp), val) 406#define this_cpu_and_4(pcp, val) percpu_to_op("and", (pcp), val) 407#define this_cpu_or_1(pcp, val) percpu_to_op("or", (pcp), val) 408#define this_cpu_or_2(pcp, val) percpu_to_op("or", (pcp), val) 409#define this_cpu_or_4(pcp, val) percpu_to_op("or", (pcp), val) 410#define this_cpu_xor_1(pcp, val) percpu_to_op("xor", (pcp), val) 411#define this_cpu_xor_2(pcp, val) percpu_to_op("xor", (pcp), val) 412#define this_cpu_xor_4(pcp, val) percpu_to_op("xor", (pcp), val) 413#define this_cpu_xchg_1(pcp, nval) percpu_xchg_op(pcp, nval) 414#define this_cpu_xchg_2(pcp, nval) percpu_xchg_op(pcp, nval) 415#define this_cpu_xchg_4(pcp, nval) percpu_xchg_op(pcp, nval) 416 417#ifndef CONFIG_M386 418#define __this_cpu_add_return_1(pcp, val) percpu_add_return_op(pcp, val) 419#define __this_cpu_add_return_2(pcp, val) percpu_add_return_op(pcp, val) 420#define __this_cpu_add_return_4(pcp, val) percpu_add_return_op(pcp, val) 421#define __this_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval) 422#define __this_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval) 423#define __this_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval) 424 425#define this_cpu_add_return_1(pcp, val) percpu_add_return_op(pcp, val) 426#define this_cpu_add_return_2(pcp, val) percpu_add_return_op(pcp, val) 427#define this_cpu_add_return_4(pcp, val) percpu_add_return_op(pcp, val) 428#define this_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval) 429#define this_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval) 430#define this_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval) 431 432#endif /* !CONFIG_M386 */ 433 434#ifdef CONFIG_X86_CMPXCHG64 435#define percpu_cmpxchg8b_double(pcp1, pcp2, o1, o2, n1, n2) \ 436({ \ 437 bool __ret; \ 438 typeof(pcp1) __o1 = (o1), __n1 = (n1); \ 439 typeof(pcp2) __o2 = (o2), __n2 = (n2); \ 440 asm volatile("cmpxchg8b "__percpu_arg(1)"\n\tsetz %0\n\t" \ 441 : "=a" (__ret), "+m" (pcp1), "+m" (pcp2), "+d" (__o2) \ 442 : "b" (__n1), "c" (__n2), "a" (__o1)); \ 443 __ret; \ 444}) 445 446#define __this_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double 447#define this_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double 448#endif /* CONFIG_X86_CMPXCHG64 */ 449 450/* 451 * Per cpu atomic 64 bit operations are only available under 64 bit. 452 * 32 bit must fall back to generic operations. 453 */ 454#ifdef CONFIG_X86_64 455#define __this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 456#define __this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val) 457#define __this_cpu_add_8(pcp, val) percpu_add_op((pcp), val) 458#define __this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val) 459#define __this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val) 460#define __this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val) 461#define __this_cpu_add_return_8(pcp, val) percpu_add_return_op(pcp, val) 462#define __this_cpu_xchg_8(pcp, nval) percpu_xchg_op(pcp, nval) 463#define __this_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval) 464 465#define this_cpu_read_8(pcp) percpu_from_op("mov", (pcp), "m"(pcp)) 466#define this_cpu_write_8(pcp, val) percpu_to_op("mov", (pcp), val) 467#define this_cpu_add_8(pcp, val) percpu_add_op((pcp), val) 468#define this_cpu_and_8(pcp, val) percpu_to_op("and", (pcp), val) 469#define this_cpu_or_8(pcp, val) percpu_to_op("or", (pcp), val) 470#define this_cpu_xor_8(pcp, val) percpu_to_op("xor", (pcp), val) 471#define this_cpu_add_return_8(pcp, val) percpu_add_return_op(pcp, val) 472#define this_cpu_xchg_8(pcp, nval) percpu_xchg_op(pcp, nval) 473#define this_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(pcp, oval, nval) 474 475/* 476 * Pretty complex macro to generate cmpxchg16 instruction. The instruction 477 * is not supported on early AMD64 processors so we must be able to emulate 478 * it in software. The address used in the cmpxchg16 instruction must be 479 * aligned to a 16 byte boundary. 480 */ 481#define percpu_cmpxchg16b_double(pcp1, pcp2, o1, o2, n1, n2) \ 482({ \ 483 bool __ret; \ 484 typeof(pcp1) __o1 = (o1), __n1 = (n1); \ 485 typeof(pcp2) __o2 = (o2), __n2 = (n2); \ 486 alternative_io("leaq %P1,%%rsi\n\tcall this_cpu_cmpxchg16b_emu\n\t", \ 487 "cmpxchg16b " __percpu_arg(1) "\n\tsetz %0\n\t", \ 488 X86_FEATURE_CX16, \ 489 ASM_OUTPUT2("=a" (__ret), "+m" (pcp1), \ 490 "+m" (pcp2), "+d" (__o2)), \ 491 "b" (__n1), "c" (__n2), "a" (__o1) : "rsi"); \ 492 __ret; \ 493}) 494 495#define __this_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double 496#define this_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double 497 498#endif 499 500/* This is not atomic against other CPUs -- CPU preemption needs to be off */ 501#define x86_test_and_clear_bit_percpu(bit, var) \ 502({ \ 503 int old__; \ 504 asm volatile("btr %2,"__percpu_arg(1)"\n\tsbbl %0,%0" \ 505 : "=r" (old__), "+m" (var) \ 506 : "dIr" (bit)); \ 507 old__; \ 508}) 509 510static __always_inline int x86_this_cpu_constant_test_bit(unsigned int nr, 511 const unsigned long __percpu *addr) 512{ 513 unsigned long __percpu *a = (unsigned long *)addr + nr / BITS_PER_LONG; 514 515 return ((1UL << (nr % BITS_PER_LONG)) & percpu_read(*a)) != 0; 516} 517 518static inline int x86_this_cpu_variable_test_bit(int nr, 519 const unsigned long __percpu *addr) 520{ 521 int oldbit; 522 523 asm volatile("bt "__percpu_arg(2)",%1\n\t" 524 "sbb %0,%0" 525 : "=r" (oldbit) 526 : "m" (*(unsigned long *)addr), "Ir" (nr)); 527 528 return oldbit; 529} 530 531#define x86_this_cpu_test_bit(nr, addr) \ 532 (__builtin_constant_p((nr)) \ 533 ? x86_this_cpu_constant_test_bit((nr), (addr)) \ 534 : x86_this_cpu_variable_test_bit((nr), (addr))) 535 536 537#include <asm-generic/percpu.h> 538 539/* We can use this directly for local CPU (faster). */ 540DECLARE_PER_CPU(unsigned long, this_cpu_off); 541 542#endif /* !__ASSEMBLY__ */ 543 544#ifdef CONFIG_SMP 545 546/* 547 * Define the "EARLY_PER_CPU" macros. These are used for some per_cpu 548 * variables that are initialized and accessed before there are per_cpu 549 * areas allocated. 550 */ 551 552#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \ 553 DEFINE_PER_CPU(_type, _name) = _initvalue; \ 554 __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \ 555 { [0 ... NR_CPUS-1] = _initvalue }; \ 556 __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map 557 558#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \ 559 EXPORT_PER_CPU_SYMBOL(_name) 560 561#define DECLARE_EARLY_PER_CPU(_type, _name) \ 562 DECLARE_PER_CPU(_type, _name); \ 563 extern __typeof__(_type) *_name##_early_ptr; \ 564 extern __typeof__(_type) _name##_early_map[] 565 566#define early_per_cpu_ptr(_name) (_name##_early_ptr) 567#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx]) 568#define early_per_cpu(_name, _cpu) \ 569 *(early_per_cpu_ptr(_name) ? \ 570 &early_per_cpu_ptr(_name)[_cpu] : \ 571 &per_cpu(_name, _cpu)) 572 573#else /* !CONFIG_SMP */ 574#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \ 575 DEFINE_PER_CPU(_type, _name) = _initvalue 576 577#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \ 578 EXPORT_PER_CPU_SYMBOL(_name) 579 580#define DECLARE_EARLY_PER_CPU(_type, _name) \ 581 DECLARE_PER_CPU(_type, _name) 582 583#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu) 584#define early_per_cpu_ptr(_name) NULL 585/* no early_per_cpu_map() */ 586 587#endif /* !CONFIG_SMP */ 588 589#endif /* _ASM_X86_PERCPU_H */ 590