linux/arch/x86/include/asm/percpu.h
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   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         this_cpu_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 arch_raw_cpu_ptr(ptr)                           \
  56({                                                      \
  57        unsigned long tcp_ptr__;                        \
  58        asm volatile("add " __percpu_arg(1) ", %0"      \
  59                     : "=r" (tcp_ptr__)                 \
  60                     : "m" (this_cpu_off), "0" (ptr));  \
  61        (typeof(*(ptr)) __kernel __force *)tcp_ptr__;   \
  62})
  63#else
  64#define __percpu_prefix         ""
  65#endif
  66
  67#define __percpu_arg(x)         __percpu_prefix "%" #x
  68
  69/*
  70 * Initialized pointers to per-cpu variables needed for the boot
  71 * processor need to use these macros to get the proper address
  72 * offset from __per_cpu_load on SMP.
  73 *
  74 * There also must be an entry in vmlinux_64.lds.S
  75 */
  76#define DECLARE_INIT_PER_CPU(var) \
  77       extern typeof(var) init_per_cpu_var(var)
  78
  79#ifdef CONFIG_X86_64_SMP
  80#define init_per_cpu_var(var)  init_per_cpu__##var
  81#else
  82#define init_per_cpu_var(var)  var
  83#endif
  84
  85/* For arch-specific code, we can use direct single-insn ops (they
  86 * don't give an lvalue though). */
  87extern void __bad_percpu_size(void);
  88
  89#define percpu_to_op(op, var, val)                      \
  90do {                                                    \
  91        typedef typeof(var) pto_T__;                    \
  92        if (0) {                                        \
  93                pto_T__ pto_tmp__;                      \
  94                pto_tmp__ = (val);                      \
  95                (void)pto_tmp__;                        \
  96        }                                               \
  97        switch (sizeof(var)) {                          \
  98        case 1:                                         \
  99                asm(op "b %1,"__percpu_arg(0)           \
 100                    : "+m" (var)                        \
 101                    : "qi" ((pto_T__)(val)));           \
 102                break;                                  \
 103        case 2:                                         \
 104                asm(op "w %1,"__percpu_arg(0)           \
 105                    : "+m" (var)                        \
 106                    : "ri" ((pto_T__)(val)));           \
 107                break;                                  \
 108        case 4:                                         \
 109                asm(op "l %1,"__percpu_arg(0)           \
 110                    : "+m" (var)                        \
 111                    : "ri" ((pto_T__)(val)));           \
 112                break;                                  \
 113        case 8:                                         \
 114                asm(op "q %1,"__percpu_arg(0)           \
 115                    : "+m" (var)                        \
 116                    : "re" ((pto_T__)(val)));           \
 117                break;                                  \
 118        default: __bad_percpu_size();                   \
 119        }                                               \
 120} while (0)
 121
 122/*
 123 * Generate a percpu add to memory instruction and optimize code
 124 * if one is added or subtracted.
 125 */
 126#define percpu_add_op(var, val)                                         \
 127do {                                                                    \
 128        typedef typeof(var) pao_T__;                                    \
 129        const int pao_ID__ = (__builtin_constant_p(val) &&              \
 130                              ((val) == 1 || (val) == -1)) ?            \
 131                                (int)(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)                         \
 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                    : "m" (var));                       \
 190                break;                                  \
 191        case 2:                                         \
 192                asm(op "w "__percpu_arg(1)",%0"         \
 193                    : "=r" (pfo_ret__)                  \
 194                    : "m" (var));                       \
 195                break;                                  \
 196        case 4:                                         \
 197                asm(op "l "__percpu_arg(1)",%0"         \
 198                    : "=r" (pfo_ret__)                  \
 199                    : "m" (var));                       \
 200                break;                                  \
 201        case 8:                                         \
 202                asm(op "q "__percpu_arg(1)",%0"         \
 203                    : "=r" (pfo_ret__)                  \
 204                    : "m" (var));                       \
 205                break;                                  \
 206        default: __bad_percpu_size();                   \
 207        }                                               \
 208        pfo_ret__;                                      \
 209})
 210
 211#define percpu_stable_op(op, var)                       \
 212({                                                      \
 213        typeof(var) pfo_ret__;                          \
 214        switch (sizeof(var)) {                          \
 215        case 1:                                         \
 216                asm(op "b "__percpu_arg(P1)",%0"        \
 217                    : "=q" (pfo_ret__)                  \
 218                    : "p" (&(var)));                    \
 219                break;                                  \
 220        case 2:                                         \
 221                asm(op "w "__percpu_arg(P1)",%0"        \
 222                    : "=r" (pfo_ret__)                  \
 223                    : "p" (&(var)));                    \
 224                break;                                  \
 225        case 4:                                         \
 226                asm(op "l "__percpu_arg(P1)",%0"        \
 227                    : "=r" (pfo_ret__)                  \
 228                    : "p" (&(var)));                    \
 229                break;                                  \
 230        case 8:                                         \
 231                asm(op "q "__percpu_arg(P1)",%0"        \
 232                    : "=r" (pfo_ret__)                  \
 233                    : "p" (&(var)));                    \
 234                break;                                  \
 235        default: __bad_percpu_size();                   \
 236        }                                               \
 237        pfo_ret__;                                      \
 238})
 239
 240#define percpu_unary_op(op, var)                        \
 241({                                                      \
 242        switch (sizeof(var)) {                          \
 243        case 1:                                         \
 244                asm(op "b "__percpu_arg(0)              \
 245                    : "+m" (var));                      \
 246                break;                                  \
 247        case 2:                                         \
 248                asm(op "w "__percpu_arg(0)              \
 249                    : "+m" (var));                      \
 250                break;                                  \
 251        case 4:                                         \
 252                asm(op "l "__percpu_arg(0)              \
 253                    : "+m" (var));                      \
 254                break;                                  \
 255        case 8:                                         \
 256                asm(op "q "__percpu_arg(0)              \
 257                    : "+m" (var));                      \
 258                break;                                  \
 259        default: __bad_percpu_size();                   \
 260        }                                               \
 261})
 262
 263/*
 264 * Add return operation
 265 */
 266#define percpu_add_return_op(var, val)                                  \
 267({                                                                      \
 268        typeof(var) paro_ret__ = val;                                   \
 269        switch (sizeof(var)) {                                          \
 270        case 1:                                                         \
 271                asm("xaddb %0, "__percpu_arg(1)                         \
 272                            : "+q" (paro_ret__), "+m" (var)             \
 273                            : : "memory");                              \
 274                break;                                                  \
 275        case 2:                                                         \
 276                asm("xaddw %0, "__percpu_arg(1)                         \
 277                            : "+r" (paro_ret__), "+m" (var)             \
 278                            : : "memory");                              \
 279                break;                                                  \
 280        case 4:                                                         \
 281                asm("xaddl %0, "__percpu_arg(1)                         \
 282                            : "+r" (paro_ret__), "+m" (var)             \
 283                            : : "memory");                              \
 284                break;                                                  \
 285        case 8:                                                         \
 286                asm("xaddq %0, "__percpu_arg(1)                         \
 287                            : "+re" (paro_ret__), "+m" (var)            \
 288                            : : "memory");                              \
 289                break;                                                  \
 290        default: __bad_percpu_size();                                   \
 291        }                                                               \
 292        paro_ret__ += val;                                              \
 293        paro_ret__;                                                     \
 294})
 295
 296/*
 297 * xchg is implemented using cmpxchg without a lock prefix. xchg is
 298 * expensive due to the implied lock prefix.  The processor cannot prefetch
 299 * cachelines if xchg is used.
 300 */
 301#define percpu_xchg_op(var, nval)                                       \
 302({                                                                      \
 303        typeof(var) pxo_ret__;                                          \
 304        typeof(var) pxo_new__ = (nval);                                 \
 305        switch (sizeof(var)) {                                          \
 306        case 1:                                                         \
 307                asm("\n\tmov "__percpu_arg(1)",%%al"                    \
 308                    "\n1:\tcmpxchgb %2, "__percpu_arg(1)                \
 309                    "\n\tjnz 1b"                                        \
 310                            : "=&a" (pxo_ret__), "+m" (var)             \
 311                            : "q" (pxo_new__)                           \
 312                            : "memory");                                \
 313                break;                                                  \
 314        case 2:                                                         \
 315                asm("\n\tmov "__percpu_arg(1)",%%ax"                    \
 316                    "\n1:\tcmpxchgw %2, "__percpu_arg(1)                \
 317                    "\n\tjnz 1b"                                        \
 318                            : "=&a" (pxo_ret__), "+m" (var)             \
 319                            : "r" (pxo_new__)                           \
 320                            : "memory");                                \
 321                break;                                                  \
 322        case 4:                                                         \
 323                asm("\n\tmov "__percpu_arg(1)",%%eax"                   \
 324                    "\n1:\tcmpxchgl %2, "__percpu_arg(1)                \
 325                    "\n\tjnz 1b"                                        \
 326                            : "=&a" (pxo_ret__), "+m" (var)             \
 327                            : "r" (pxo_new__)                           \
 328                            : "memory");                                \
 329                break;                                                  \
 330        case 8:                                                         \
 331                asm("\n\tmov "__percpu_arg(1)",%%rax"                   \
 332                    "\n1:\tcmpxchgq %2, "__percpu_arg(1)                \
 333                    "\n\tjnz 1b"                                        \
 334                            : "=&a" (pxo_ret__), "+m" (var)             \
 335                            : "r" (pxo_new__)                           \
 336                            : "memory");                                \
 337                break;                                                  \
 338        default: __bad_percpu_size();                                   \
 339        }                                                               \
 340        pxo_ret__;                                                      \
 341})
 342
 343/*
 344 * cmpxchg has no such implied lock semantics as a result it is much
 345 * more efficient for cpu local operations.
 346 */
 347#define percpu_cmpxchg_op(var, oval, nval)                              \
 348({                                                                      \
 349        typeof(var) pco_ret__;                                          \
 350        typeof(var) pco_old__ = (oval);                                 \
 351        typeof(var) pco_new__ = (nval);                                 \
 352        switch (sizeof(var)) {                                          \
 353        case 1:                                                         \
 354                asm("cmpxchgb %2, "__percpu_arg(1)                      \
 355                            : "=a" (pco_ret__), "+m" (var)              \
 356                            : "q" (pco_new__), "0" (pco_old__)          \
 357                            : "memory");                                \
 358                break;                                                  \
 359        case 2:                                                         \
 360                asm("cmpxchgw %2, "__percpu_arg(1)                      \
 361                            : "=a" (pco_ret__), "+m" (var)              \
 362                            : "r" (pco_new__), "0" (pco_old__)          \
 363                            : "memory");                                \
 364                break;                                                  \
 365        case 4:                                                         \
 366                asm("cmpxchgl %2, "__percpu_arg(1)                      \
 367                            : "=a" (pco_ret__), "+m" (var)              \
 368                            : "r" (pco_new__), "0" (pco_old__)          \
 369                            : "memory");                                \
 370                break;                                                  \
 371        case 8:                                                         \
 372                asm("cmpxchgq %2, "__percpu_arg(1)                      \
 373                            : "=a" (pco_ret__), "+m" (var)              \
 374                            : "r" (pco_new__), "0" (pco_old__)          \
 375                            : "memory");                                \
 376                break;                                                  \
 377        default: __bad_percpu_size();                                   \
 378        }                                                               \
 379        pco_ret__;                                                      \
 380})
 381
 382/*
 383 * this_cpu_read() makes gcc load the percpu variable every time it is
 384 * accessed while this_cpu_read_stable() allows the value to be cached.
 385 * this_cpu_read_stable() is more efficient and can be used if its value
 386 * is guaranteed to be valid across cpus.  The current users include
 387 * get_current() and get_thread_info() both of which are actually
 388 * per-thread variables implemented as per-cpu variables and thus
 389 * stable for the duration of the respective task.
 390 */
 391#define this_cpu_read_stable(var)       percpu_stable_op("mov", var)
 392
 393#define raw_cpu_read_1(pcp)             percpu_from_op("mov", pcp)
 394#define raw_cpu_read_2(pcp)             percpu_from_op("mov", pcp)
 395#define raw_cpu_read_4(pcp)             percpu_from_op("mov", pcp)
 396
 397#define raw_cpu_write_1(pcp, val)       percpu_to_op("mov", (pcp), val)
 398#define raw_cpu_write_2(pcp, val)       percpu_to_op("mov", (pcp), val)
 399#define raw_cpu_write_4(pcp, val)       percpu_to_op("mov", (pcp), val)
 400#define raw_cpu_add_1(pcp, val)         percpu_add_op((pcp), val)
 401#define raw_cpu_add_2(pcp, val)         percpu_add_op((pcp), val)
 402#define raw_cpu_add_4(pcp, val)         percpu_add_op((pcp), val)
 403#define raw_cpu_and_1(pcp, val)         percpu_to_op("and", (pcp), val)
 404#define raw_cpu_and_2(pcp, val)         percpu_to_op("and", (pcp), val)
 405#define raw_cpu_and_4(pcp, val)         percpu_to_op("and", (pcp), val)
 406#define raw_cpu_or_1(pcp, val)          percpu_to_op("or", (pcp), val)
 407#define raw_cpu_or_2(pcp, val)          percpu_to_op("or", (pcp), val)
 408#define raw_cpu_or_4(pcp, val)          percpu_to_op("or", (pcp), val)
 409#define raw_cpu_xchg_1(pcp, val)        percpu_xchg_op(pcp, val)
 410#define raw_cpu_xchg_2(pcp, val)        percpu_xchg_op(pcp, val)
 411#define raw_cpu_xchg_4(pcp, val)        percpu_xchg_op(pcp, val)
 412
 413#define this_cpu_read_1(pcp)            percpu_from_op("mov", pcp)
 414#define this_cpu_read_2(pcp)            percpu_from_op("mov", pcp)
 415#define this_cpu_read_4(pcp)            percpu_from_op("mov", pcp)
 416#define this_cpu_write_1(pcp, val)      percpu_to_op("mov", (pcp), val)
 417#define this_cpu_write_2(pcp, val)      percpu_to_op("mov", (pcp), val)
 418#define this_cpu_write_4(pcp, val)      percpu_to_op("mov", (pcp), val)
 419#define this_cpu_add_1(pcp, val)        percpu_add_op((pcp), val)
 420#define this_cpu_add_2(pcp, val)        percpu_add_op((pcp), val)
 421#define this_cpu_add_4(pcp, val)        percpu_add_op((pcp), val)
 422#define this_cpu_and_1(pcp, val)        percpu_to_op("and", (pcp), val)
 423#define this_cpu_and_2(pcp, val)        percpu_to_op("and", (pcp), val)
 424#define this_cpu_and_4(pcp, val)        percpu_to_op("and", (pcp), val)
 425#define this_cpu_or_1(pcp, val)         percpu_to_op("or", (pcp), val)
 426#define this_cpu_or_2(pcp, val)         percpu_to_op("or", (pcp), val)
 427#define this_cpu_or_4(pcp, val)         percpu_to_op("or", (pcp), val)
 428#define this_cpu_xchg_1(pcp, nval)      percpu_xchg_op(pcp, nval)
 429#define this_cpu_xchg_2(pcp, nval)      percpu_xchg_op(pcp, nval)
 430#define this_cpu_xchg_4(pcp, nval)      percpu_xchg_op(pcp, nval)
 431
 432#define raw_cpu_add_return_1(pcp, val)          percpu_add_return_op(pcp, val)
 433#define raw_cpu_add_return_2(pcp, val)          percpu_add_return_op(pcp, val)
 434#define raw_cpu_add_return_4(pcp, val)          percpu_add_return_op(pcp, val)
 435#define raw_cpu_cmpxchg_1(pcp, oval, nval)      percpu_cmpxchg_op(pcp, oval, nval)
 436#define raw_cpu_cmpxchg_2(pcp, oval, nval)      percpu_cmpxchg_op(pcp, oval, nval)
 437#define raw_cpu_cmpxchg_4(pcp, oval, nval)      percpu_cmpxchg_op(pcp, oval, nval)
 438
 439#define this_cpu_add_return_1(pcp, val)         percpu_add_return_op(pcp, val)
 440#define this_cpu_add_return_2(pcp, val)         percpu_add_return_op(pcp, val)
 441#define this_cpu_add_return_4(pcp, val)         percpu_add_return_op(pcp, val)
 442#define this_cpu_cmpxchg_1(pcp, oval, nval)     percpu_cmpxchg_op(pcp, oval, nval)
 443#define this_cpu_cmpxchg_2(pcp, oval, nval)     percpu_cmpxchg_op(pcp, oval, nval)
 444#define this_cpu_cmpxchg_4(pcp, oval, nval)     percpu_cmpxchg_op(pcp, oval, nval)
 445
 446#ifdef CONFIG_X86_CMPXCHG64
 447#define percpu_cmpxchg8b_double(pcp1, pcp2, o1, o2, n1, n2)             \
 448({                                                                      \
 449        bool __ret;                                                     \
 450        typeof(pcp1) __o1 = (o1), __n1 = (n1);                          \
 451        typeof(pcp2) __o2 = (o2), __n2 = (n2);                          \
 452        asm volatile("cmpxchg8b "__percpu_arg(1)"\n\tsetz %0\n\t"       \
 453                    : "=a" (__ret), "+m" (pcp1), "+m" (pcp2), "+d" (__o2) \
 454                    :  "b" (__n1), "c" (__n2), "a" (__o1));             \
 455        __ret;                                                          \
 456})
 457
 458#define raw_cpu_cmpxchg_double_4        percpu_cmpxchg8b_double
 459#define this_cpu_cmpxchg_double_4       percpu_cmpxchg8b_double
 460#endif /* CONFIG_X86_CMPXCHG64 */
 461
 462/*
 463 * Per cpu atomic 64 bit operations are only available under 64 bit.
 464 * 32 bit must fall back to generic operations.
 465 */
 466#ifdef CONFIG_X86_64
 467#define raw_cpu_read_8(pcp)                     percpu_from_op("mov", pcp)
 468#define raw_cpu_write_8(pcp, val)               percpu_to_op("mov", (pcp), val)
 469#define raw_cpu_add_8(pcp, val)                 percpu_add_op((pcp), val)
 470#define raw_cpu_and_8(pcp, val)                 percpu_to_op("and", (pcp), val)
 471#define raw_cpu_or_8(pcp, val)                  percpu_to_op("or", (pcp), val)
 472#define raw_cpu_add_return_8(pcp, val)          percpu_add_return_op(pcp, val)
 473#define raw_cpu_xchg_8(pcp, nval)               percpu_xchg_op(pcp, nval)
 474#define raw_cpu_cmpxchg_8(pcp, oval, nval)      percpu_cmpxchg_op(pcp, oval, nval)
 475
 476#define this_cpu_read_8(pcp)                    percpu_from_op("mov", pcp)
 477#define this_cpu_write_8(pcp, val)              percpu_to_op("mov", (pcp), val)
 478#define this_cpu_add_8(pcp, val)                percpu_add_op((pcp), val)
 479#define this_cpu_and_8(pcp, val)                percpu_to_op("and", (pcp), val)
 480#define this_cpu_or_8(pcp, val)                 percpu_to_op("or", (pcp), val)
 481#define this_cpu_add_return_8(pcp, val)         percpu_add_return_op(pcp, val)
 482#define this_cpu_xchg_8(pcp, nval)              percpu_xchg_op(pcp, nval)
 483#define this_cpu_cmpxchg_8(pcp, oval, nval)     percpu_cmpxchg_op(pcp, oval, nval)
 484
 485/*
 486 * Pretty complex macro to generate cmpxchg16 instruction.  The instruction
 487 * is not supported on early AMD64 processors so we must be able to emulate
 488 * it in software.  The address used in the cmpxchg16 instruction must be
 489 * aligned to a 16 byte boundary.
 490 */
 491#define percpu_cmpxchg16b_double(pcp1, pcp2, o1, o2, n1, n2)            \
 492({                                                                      \
 493        bool __ret;                                                     \
 494        typeof(pcp1) __o1 = (o1), __n1 = (n1);                          \
 495        typeof(pcp2) __o2 = (o2), __n2 = (n2);                          \
 496        alternative_io("leaq %P1,%%rsi\n\tcall this_cpu_cmpxchg16b_emu\n\t", \
 497                       "cmpxchg16b " __percpu_arg(1) "\n\tsetz %0\n\t", \
 498                       X86_FEATURE_CX16,                                \
 499                       ASM_OUTPUT2("=a" (__ret), "+m" (pcp1),           \
 500                                   "+m" (pcp2), "+d" (__o2)),           \
 501                       "b" (__n1), "c" (__n2), "a" (__o1) : "rsi");     \
 502        __ret;                                                          \
 503})
 504
 505#define raw_cpu_cmpxchg_double_8        percpu_cmpxchg16b_double
 506#define this_cpu_cmpxchg_double_8       percpu_cmpxchg16b_double
 507
 508#endif
 509
 510/* This is not atomic against other CPUs -- CPU preemption needs to be off */
 511#define x86_test_and_clear_bit_percpu(bit, var)                         \
 512({                                                                      \
 513        int old__;                                                      \
 514        asm volatile("btr %2,"__percpu_arg(1)"\n\tsbbl %0,%0"           \
 515                     : "=r" (old__), "+m" (var)                         \
 516                     : "dIr" (bit));                                    \
 517        old__;                                                          \
 518})
 519
 520static __always_inline int x86_this_cpu_constant_test_bit(unsigned int nr,
 521                        const unsigned long __percpu *addr)
 522{
 523        unsigned long __percpu *a = (unsigned long *)addr + nr / BITS_PER_LONG;
 524
 525#ifdef CONFIG_X86_64
 526        return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_8(*a)) != 0;
 527#else
 528        return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_4(*a)) != 0;
 529#endif
 530}
 531
 532static inline int x86_this_cpu_variable_test_bit(int nr,
 533                        const unsigned long __percpu *addr)
 534{
 535        int oldbit;
 536
 537        asm volatile("bt "__percpu_arg(2)",%1\n\t"
 538                        "sbb %0,%0"
 539                        : "=r" (oldbit)
 540                        : "m" (*(unsigned long *)addr), "Ir" (nr));
 541
 542        return oldbit;
 543}
 544
 545#define x86_this_cpu_test_bit(nr, addr)                 \
 546        (__builtin_constant_p((nr))                     \
 547         ? x86_this_cpu_constant_test_bit((nr), (addr)) \
 548         : x86_this_cpu_variable_test_bit((nr), (addr)))
 549
 550
 551#include <asm-generic/percpu.h>
 552
 553/* We can use this directly for local CPU (faster). */
 554DECLARE_PER_CPU_READ_MOSTLY(unsigned long, this_cpu_off);
 555
 556#endif /* !__ASSEMBLY__ */
 557
 558#ifdef CONFIG_SMP
 559
 560/*
 561 * Define the "EARLY_PER_CPU" macros.  These are used for some per_cpu
 562 * variables that are initialized and accessed before there are per_cpu
 563 * areas allocated.
 564 */
 565
 566#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue)                  \
 567        DEFINE_PER_CPU(_type, _name) = _initvalue;                      \
 568        __typeof__(_type) _name##_early_map[NR_CPUS] __initdata =       \
 569                                { [0 ... NR_CPUS-1] = _initvalue };     \
 570        __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
 571
 572#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue)      \
 573        DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue;          \
 574        __typeof__(_type) _name##_early_map[NR_CPUS] __initdata =       \
 575                                { [0 ... NR_CPUS-1] = _initvalue };     \
 576        __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
 577
 578#define EXPORT_EARLY_PER_CPU_SYMBOL(_name)                      \
 579        EXPORT_PER_CPU_SYMBOL(_name)
 580
 581#define DECLARE_EARLY_PER_CPU(_type, _name)                     \
 582        DECLARE_PER_CPU(_type, _name);                          \
 583        extern __typeof__(_type) *_name##_early_ptr;            \
 584        extern __typeof__(_type)  _name##_early_map[]
 585
 586#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name)         \
 587        DECLARE_PER_CPU_READ_MOSTLY(_type, _name);              \
 588        extern __typeof__(_type) *_name##_early_ptr;            \
 589        extern __typeof__(_type)  _name##_early_map[]
 590
 591#define early_per_cpu_ptr(_name) (_name##_early_ptr)
 592#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
 593#define early_per_cpu(_name, _cpu)                              \
 594        *(early_per_cpu_ptr(_name) ?                            \
 595                &early_per_cpu_ptr(_name)[_cpu] :               \
 596                &per_cpu(_name, _cpu))
 597
 598#else   /* !CONFIG_SMP */
 599#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue)          \
 600        DEFINE_PER_CPU(_type, _name) = _initvalue
 601
 602#define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue)      \
 603        DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue
 604
 605#define EXPORT_EARLY_PER_CPU_SYMBOL(_name)                      \
 606        EXPORT_PER_CPU_SYMBOL(_name)
 607
 608#define DECLARE_EARLY_PER_CPU(_type, _name)                     \
 609        DECLARE_PER_CPU(_type, _name)
 610
 611#define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name)         \
 612        DECLARE_PER_CPU_READ_MOSTLY(_type, _name)
 613
 614#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
 615#define early_per_cpu_ptr(_name) NULL
 616/* no early_per_cpu_map() */
 617
 618#endif  /* !CONFIG_SMP */
 619
 620#endif /* _ASM_X86_PERCPU_H */
 621