include/linux/percpu.h

   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 #ifdef CONFIG_SMP
  43
  44 /* minimum unit size, also is the maximum supported allocation size */
  45 #define PCPU_MIN_UNIT_SIZE              PFN_ALIGN(64 << 10)
  46
  47 /*
  48  * Percpu allocator can serve percpu allocations before slab is
  49  * initialized which allows slab to depend on the percpu allocator.
  50  * The following two parameters decide how much resource to
  51  * preallocate for this.  Keep PERCPU_DYNAMIC_RESERVE equal to or
  52  * larger than PERCPU_DYNAMIC_EARLY_SIZE.
  53  */
  54 #define PERCPU_DYNAMIC_EARLY_SLOTS      128
  55 #define PERCPU_DYNAMIC_EARLY_SIZE       (12 << 10)
  56
  57 /*
  58  * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
  59  * back on the first chunk for dynamic percpu allocation if arch is
  60  * manually allocating and mapping it for faster access (as a part of
  61  * large page mapping for example).
  62  *
  63  * The following values give between one and two pages of free space
  64  * after typical minimal boot (2-way SMP, single disk and NIC) with
  65  * both defconfig and a distro config on x86_64 and 32.  More
  66  * intelligent way to determine this would be nice.
  67  */
  68 #if BITS_PER_LONG > 32
  69 #define PERCPU_DYNAMIC_RESERVE          (20 << 10)
  70 #else
  71 #define PERCPU_DYNAMIC_RESERVE          (12 << 10)
  72 #endif
  73
  74 extern void *pcpu_base_addr;
  75 extern const unsigned long *pcpu_unit_offsets;
  76
  77 struct pcpu_group_info {
  78         int                     nr_units;       /* aligned # of units */
  79         unsigned long           base_offset;    /* base address offset */
  80         unsigned int            *cpu_map;       /* unit->cpu map, empty
  81                                                  * entries contain NR_CPUS */
  82 };
  83
  84 struct pcpu_alloc_info {
  85         size_t                  static_size;
  86         size_t                  reserved_size;
  87         size_t                  dyn_size;
  88         size_t                  unit_size;
  89         size_t                  atom_size;
  90         size_t                  alloc_size;
  91         size_t                  __ai_size;      /* internal, don't use */
  92         int                     nr_groups;      /* 0 if grouping unnecessary */
  93         struct pcpu_group_info  groups[];
  94 };
  95
  96 enum pcpu_fc {
  97         PCPU_FC_AUTO,
  98         PCPU_FC_EMBED,
  99         PCPU_FC_PAGE,
 100
 101         PCPU_FC_NR,
 102 };
 103 extern const char *pcpu_fc_names[PCPU_FC_NR];
 104
 105 extern enum pcpu_fc pcpu_chosen_fc;
 106
 107 typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
 108                                      size_t align);
 109 typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
 110 typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
 111 typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
 112
 113 extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
 114                                                              int nr_units);
 115 extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
 116
 117 extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
 118                                          void *base_addr);
 119
 120 #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
 121 extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
 122                                 size_t atom_size,
 123                                 pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
 124                                 pcpu_fc_alloc_fn_t alloc_fn,
 125                                 pcpu_fc_free_fn_t free_fn);
 126 #endif
 127
 128 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
 129 extern int __init pcpu_page_first_chunk(size_t reserved_size,
 130                                 pcpu_fc_alloc_fn_t alloc_fn,
 131                                 pcpu_fc_free_fn_t free_fn,
 132                                 pcpu_fc_populate_pte_fn_t populate_pte_fn);
 133 #endif
 134
 135 /*
 136  * Use this to get to a cpu's version of the per-cpu object
 137  * dynamically allocated. Non-atomic access to the current CPU's
 138  * version should probably be combined with get_cpu()/put_cpu().
 139  */
 140 #define per_cpu_ptr(ptr, cpu)   SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
 141
 142 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
 143 extern bool is_kernel_percpu_address(unsigned long addr);
 144
 145 #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
 146 extern void __init setup_per_cpu_areas(void);
 147 #endif
 148 extern void __init percpu_init_late(void);
 149
 150 #else /* CONFIG_SMP */
 151
 152 #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
 153
 154 /* can't distinguish from other static vars, always false */
 155 static inline bool is_kernel_percpu_address(unsigned long addr)
 156 {
 157         return false;
 158 }
 159
 160 static inline void __init setup_per_cpu_areas(void) { }
 161
 162 static inline void __init percpu_init_late(void) { }
 163
 164 static inline void *pcpu_lpage_remapped(void *kaddr)
 165 {
 166         return NULL;
 167 }
 168
 169 #endif /* CONFIG_SMP */
 170
 171 extern void __percpu *__alloc_percpu(size_t size, size_t align);
 172 extern void free_percpu(void __percpu *__pdata);
 173 extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
 174
 175 #define alloc_percpu(type)      \
 176         (typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
 177
 178 /*
 179  * Optional methods for optimized non-lvalue per-cpu variable access.
 180  *
 181  * @var can be a percpu variable or a field of it and its size should
 182  * equal char, int or long.  percpu_read() evaluates to a lvalue and
 183  * all others to void.
 184  *
 185  * These operations are guaranteed to be atomic w.r.t. preemption.
 186  * The generic versions use plain get/put_cpu_var().  Archs are
 187  * encouraged to implement single-instruction alternatives which don't
 188  * require preemption protection.
 189  */
 190 #ifndef percpu_read
 191 # define percpu_read(var)                                               \
 192   ({                                                                    \
 193         typeof(var) *pr_ptr__ = &(var);                                 \
 194         typeof(var) pr_ret__;                                           \
 195         pr_ret__ = get_cpu_var(*pr_ptr__);                              \
 196         put_cpu_var(*pr_ptr__);                                         \
 197         pr_ret__;                                                       \
 198   })
 199 #endif
 200
 201 #define __percpu_generic_to_op(var, val, op)                            \
 202 do {                                                                    \
 203         typeof(var) *pgto_ptr__ = &(var);                               \
 204         get_cpu_var(*pgto_ptr__) op val;                                \
 205         put_cpu_var(*pgto_ptr__);                                       \
 206 } while (0)
 207
 208 #ifndef percpu_write
 209 # define percpu_write(var, val)         __percpu_generic_to_op(var, (val), =)
 210 #endif
 211
 212 #ifndef percpu_add
 213 # define percpu_add(var, val)           __percpu_generic_to_op(var, (val), +=)
 214 #endif
 215
 216 #ifndef percpu_sub
 217 # define percpu_sub(var, val)           __percpu_generic_to_op(var, (val), -=)
 218 #endif
 219
 220 #ifndef percpu_and
 221 # define percpu_and(var, val)           __percpu_generic_to_op(var, (val), &=)
 222 #endif
 223
 224 #ifndef percpu_or
 225 # define percpu_or(var, val)            __percpu_generic_to_op(var, (val), |=)
 226 #endif
 227
 228 #ifndef percpu_xor
 229 # define percpu_xor(var, val)           __percpu_generic_to_op(var, (val), ^=)
 230 #endif
 231
 232 /*
 233  * Branching function to split up a function into a set of functions that
 234  * are called for different scalar sizes of the objects handled.
 235  */
 236
 237 extern void __bad_size_call_parameter(void);
 238
 239 #define __pcpu_size_call_return(stem, variable)                         \
 240 ({      typeof(variable) pscr_ret__;                                    \
 241         __verify_pcpu_ptr(&(variable));                                 \
 242         switch(sizeof(variable)) {                                      \
 243         case 1: pscr_ret__ = stem##1(variable);break;                   \
 244         case 2: pscr_ret__ = stem##2(variable);break;                   \
 245         case 4: pscr_ret__ = stem##4(variable);break;                   \
 246         case 8: pscr_ret__ = stem##8(variable);break;                   \
 247         default:                                                        \
 248                 __bad_size_call_parameter();break;                      \
 249         }                                                               \
 250         pscr_ret__;                                                     \
 251 })
 252
 253 #define __pcpu_size_call(stem, variable, ...)                           \
 254 do {                                                                    \
 255         __verify_pcpu_ptr(&(variable));                                 \
 256         switch(sizeof(variable)) {                                      \
 257                 case 1: stem##1(variable, __VA_ARGS__);break;           \
 258                 case 2: stem##2(variable, __VA_ARGS__);break;           \
 259                 case 4: stem##4(variable, __VA_ARGS__);break;           \
 260                 case 8: stem##8(variable, __VA_ARGS__);break;           \
 261                 default:                                                \
 262                         __bad_size_call_parameter();break;              \
 263         }                                                               \
 264 } while (0)
 265
 266 /*
 267  * Optimized manipulation for memory allocated through the per cpu
 268  * allocator or for addresses of per cpu variables.
 269  *
 270  * These operation guarantee exclusivity of access for other operations
 271  * on the *same* processor. The assumption is that per cpu data is only
 272  * accessed by a single processor instance (the current one).
 273  *
 274  * The first group is used for accesses that must be done in a
 275  * preemption safe way since we know that the context is not preempt
 276  * safe. Interrupts may occur. If the interrupt modifies the variable
 277  * too then RMW actions will not be reliable.
 278  *
 279  * The arch code can provide optimized functions in two ways:
 280  *
 281  * 1. Override the function completely. F.e. define this_cpu_add().
 282  *    The arch must then ensure that the various scalar format passed
 283  *    are handled correctly.
 284  *
 285  * 2. Provide functions for certain scalar sizes. F.e. provide
 286  *    this_cpu_add_2() to provide per cpu atomic operations for 2 byte
 287  *    sized RMW actions. If arch code does not provide operations for
 288  *    a scalar size then the fallback in the generic code will be
 289  *    used.
 290  */
 291
 292 #define _this_cpu_generic_read(pcp)                                     \
 293 ({      typeof(pcp) ret__;                                              \
 294         preempt_disable();                                              \
 295         ret__ = *this_cpu_ptr(&(pcp));                                  \
 296         preempt_enable();                                               \
 297         ret__;                                                          \
 298 })
 299
 300 #ifndef this_cpu_read
 301 # ifndef this_cpu_read_1
 302 #  define this_cpu_read_1(pcp)  _this_cpu_generic_read(pcp)
 303 # endif
 304 # ifndef this_cpu_read_2
 305 #  define this_cpu_read_2(pcp)  _this_cpu_generic_read(pcp)
 306 # endif
 307 # ifndef this_cpu_read_4
 308 #  define this_cpu_read_4(pcp)  _this_cpu_generic_read(pcp)
 309 # endif
 310 # ifndef this_cpu_read_8
 311 #  define this_cpu_read_8(pcp)  _this_cpu_generic_read(pcp)
 312 # endif
 313 # define this_cpu_read(pcp)     __pcpu_size_call_return(this_cpu_read_, (pcp))
 314 #endif
 315
 316 #define _this_cpu_generic_to_op(pcp, val, op)                           \
 317 do {                                                                    \
 318         preempt_disable();                                              \
 319         *__this_cpu_ptr(&(pcp)) op val;                                 \
 320         preempt_enable();                                               \
 321 } while (0)
 322
 323 #ifndef this_cpu_write
 324 # ifndef this_cpu_write_1
 325 #  define this_cpu_write_1(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 326 # endif
 327 # ifndef this_cpu_write_2
 328 #  define this_cpu_write_2(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 329 # endif
 330 # ifndef this_cpu_write_4
 331 #  define this_cpu_write_4(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 332 # endif
 333 # ifndef this_cpu_write_8
 334 #  define this_cpu_write_8(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 335 # endif
 336 # define this_cpu_write(pcp, val)       __pcpu_size_call(this_cpu_write_, (pcp), (val))
 337 #endif
 338
 339 #ifndef this_cpu_add
 340 # ifndef this_cpu_add_1
 341 #  define this_cpu_add_1(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 342 # endif
 343 # ifndef this_cpu_add_2
 344 #  define this_cpu_add_2(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 345 # endif
 346 # ifndef this_cpu_add_4
 347 #  define this_cpu_add_4(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 348 # endif
 349 # ifndef this_cpu_add_8
 350 #  define this_cpu_add_8(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 351 # endif
 352 # define this_cpu_add(pcp, val)         __pcpu_size_call(this_cpu_add_, (pcp), (val))
 353 #endif
 354
 355 #ifndef this_cpu_sub
 356 # define this_cpu_sub(pcp, val)         this_cpu_add((pcp), -(val))
 357 #endif
 358
 359 #ifndef this_cpu_inc
 360 # define this_cpu_inc(pcp)              this_cpu_add((pcp), 1)
 361 #endif
 362
 363 #ifndef this_cpu_dec
 364 # define this_cpu_dec(pcp)              this_cpu_sub((pcp), 1)
 365 #endif
 366
 367 #ifndef this_cpu_and
 368 # ifndef this_cpu_and_1
 369 #  define this_cpu_and_1(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 370 # endif
 371 # ifndef this_cpu_and_2
 372 #  define this_cpu_and_2(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 373 # endif
 374 # ifndef this_cpu_and_4
 375 #  define this_cpu_and_4(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 376 # endif
 377 # ifndef this_cpu_and_8
 378 #  define this_cpu_and_8(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 379 # endif
 380 # define this_cpu_and(pcp, val)         __pcpu_size_call(this_cpu_and_, (pcp), (val))
 381 #endif
 382
 383 #ifndef this_cpu_or
 384 # ifndef this_cpu_or_1
 385 #  define this_cpu_or_1(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 386 # endif
 387 # ifndef this_cpu_or_2
 388 #  define this_cpu_or_2(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 389 # endif
 390 # ifndef this_cpu_or_4
 391 #  define this_cpu_or_4(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 392 # endif
 393 # ifndef this_cpu_or_8
 394 #  define this_cpu_or_8(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 395 # endif
 396 # define this_cpu_or(pcp, val)          __pcpu_size_call(this_cpu_or_, (pcp), (val))
 397 #endif
 398
 399 #ifndef this_cpu_xor
 400 # ifndef this_cpu_xor_1
 401 #  define this_cpu_xor_1(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 402 # endif
 403 # ifndef this_cpu_xor_2
 404 #  define this_cpu_xor_2(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 405 # endif
 406 # ifndef this_cpu_xor_4
 407 #  define this_cpu_xor_4(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 408 # endif
 409 # ifndef this_cpu_xor_8
 410 #  define this_cpu_xor_8(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 411 # endif
 412 # define this_cpu_xor(pcp, val)         __pcpu_size_call(this_cpu_or_, (pcp), (val))
 413 #endif
 414
 415 /*
 416  * Generic percpu operations that do not require preemption handling.
 417  * Either we do not care about races or the caller has the
 418  * responsibility of handling preemptions issues. Arch code can still
 419  * override these instructions since the arch per cpu code may be more
 420  * efficient and may actually get race freeness for free (that is the
 421  * case for x86 for example).
 422  *
 423  * If there is no other protection through preempt disable and/or
 424  * disabling interupts then one of these RMW operations can show unexpected
 425  * behavior because the execution thread was rescheduled on another processor
 426  * or an interrupt occurred and the same percpu variable was modified from
 427  * the interrupt context.
 428  */
 429 #ifndef __this_cpu_read
 430 # ifndef __this_cpu_read_1
 431 #  define __this_cpu_read_1(pcp)        (*__this_cpu_ptr(&(pcp)))
 432 # endif
 433 # ifndef __this_cpu_read_2
 434 #  define __this_cpu_read_2(pcp)        (*__this_cpu_ptr(&(pcp)))
 435 # endif
 436 # ifndef __this_cpu_read_4
 437 #  define __this_cpu_read_4(pcp)        (*__this_cpu_ptr(&(pcp)))
 438 # endif
 439 # ifndef __this_cpu_read_8
 440 #  define __this_cpu_read_8(pcp)        (*__this_cpu_ptr(&(pcp)))
 441 # endif
 442 # define __this_cpu_read(pcp)   __pcpu_size_call_return(__this_cpu_read_, (pcp))
 443 #endif
 444
 445 #define __this_cpu_generic_to_op(pcp, val, op)                          \
 446 do {                                                                    \
 447         *__this_cpu_ptr(&(pcp)) op val;                                 \
 448 } while (0)
 449
 450 #ifndef __this_cpu_write
 451 # ifndef __this_cpu_write_1
 452 #  define __this_cpu_write_1(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 453 # endif
 454 # ifndef __this_cpu_write_2
 455 #  define __this_cpu_write_2(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 456 # endif
 457 # ifndef __this_cpu_write_4
 458 #  define __this_cpu_write_4(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 459 # endif
 460 # ifndef __this_cpu_write_8
 461 #  define __this_cpu_write_8(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 462 # endif
 463 # define __this_cpu_write(pcp, val)     __pcpu_size_call(__this_cpu_write_, (pcp), (val))
 464 #endif
 465
 466 #ifndef __this_cpu_add
 467 # ifndef __this_cpu_add_1
 468 #  define __this_cpu_add_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 469 # endif
 470 # ifndef __this_cpu_add_2
 471 #  define __this_cpu_add_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 472 # endif
 473 # ifndef __this_cpu_add_4
 474 #  define __this_cpu_add_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 475 # endif
 476 # ifndef __this_cpu_add_8
 477 #  define __this_cpu_add_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 478 # endif
 479 # define __this_cpu_add(pcp, val)       __pcpu_size_call(__this_cpu_add_, (pcp), (val))
 480 #endif
 481
 482 #ifndef __this_cpu_sub
 483 # define __this_cpu_sub(pcp, val)       __this_cpu_add((pcp), -(val))
 484 #endif
 485
 486 #ifndef __this_cpu_inc
 487 # define __this_cpu_inc(pcp)            __this_cpu_add((pcp), 1)
 488 #endif
 489
 490 #ifndef __this_cpu_dec
 491 # define __this_cpu_dec(pcp)            __this_cpu_sub((pcp), 1)
 492 #endif
 493
 494 #ifndef __this_cpu_and
 495 # ifndef __this_cpu_and_1
 496 #  define __this_cpu_and_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 497 # endif
 498 # ifndef __this_cpu_and_2
 499 #  define __this_cpu_and_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 500 # endif
 501 # ifndef __this_cpu_and_4
 502 #  define __this_cpu_and_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 503 # endif
 504 # ifndef __this_cpu_and_8
 505 #  define __this_cpu_and_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 506 # endif
 507 # define __this_cpu_and(pcp, val)       __pcpu_size_call(__this_cpu_and_, (pcp), (val))
 508 #endif
 509
 510 #ifndef __this_cpu_or
 511 # ifndef __this_cpu_or_1
 512 #  define __this_cpu_or_1(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 513 # endif
 514 # ifndef __this_cpu_or_2
 515 #  define __this_cpu_or_2(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 516 # endif
 517 # ifndef __this_cpu_or_4
 518 #  define __this_cpu_or_4(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 519 # endif
 520 # ifndef __this_cpu_or_8
 521 #  define __this_cpu_or_8(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 522 # endif
 523 # define __this_cpu_or(pcp, val)        __pcpu_size_call(__this_cpu_or_, (pcp), (val))
 524 #endif
 525
 526 #ifndef __this_cpu_xor
 527 # ifndef __this_cpu_xor_1
 528 #  define __this_cpu_xor_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 529 # endif
 530 # ifndef __this_cpu_xor_2
 531 #  define __this_cpu_xor_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 532 # endif
 533 # ifndef __this_cpu_xor_4
 534 #  define __this_cpu_xor_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 535 # endif
 536 # ifndef __this_cpu_xor_8
 537 #  define __this_cpu_xor_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 538 # endif
 539 # define __this_cpu_xor(pcp, val)       __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
 540 #endif
 541
 542 /*
 543  * IRQ safe versions of the per cpu RMW operations. Note that these operations
 544  * are *not* safe against modification of the same variable from another
 545  * processors (which one gets when using regular atomic operations)
 546  . They are guaranteed to be atomic vs. local interrupts and
 547  * preemption only.
 548  */
 549 #define irqsafe_cpu_generic_to_op(pcp, val, op)                         \
 550 do {                                                                    \
 551         unsigned long flags;                                            \
 552         local_irq_save(flags);                                          \
 553         *__this_cpu_ptr(&(pcp)) op val;                                 \
 554         local_irq_restore(flags);                                       \
 555 } while (0)
 556
 557 #ifndef irqsafe_cpu_add
 558 # ifndef irqsafe_cpu_add_1
 559 #  define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 560 # endif
 561 # ifndef irqsafe_cpu_add_2
 562 #  define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 563 # endif
 564 # ifndef irqsafe_cpu_add_4
 565 #  define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 566 # endif
 567 # ifndef irqsafe_cpu_add_8
 568 #  define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 569 # endif
 570 # define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val))
 571 #endif
 572
 573 #ifndef irqsafe_cpu_sub
 574 # define irqsafe_cpu_sub(pcp, val)      irqsafe_cpu_add((pcp), -(val))
 575 #endif
 576
 577 #ifndef irqsafe_cpu_inc
 578 # define irqsafe_cpu_inc(pcp)   irqsafe_cpu_add((pcp), 1)
 579 #endif
 580
 581 #ifndef irqsafe_cpu_dec
 582 # define irqsafe_cpu_dec(pcp)   irqsafe_cpu_sub((pcp), 1)
 583 #endif
 584
 585 #ifndef irqsafe_cpu_and
 586 # ifndef irqsafe_cpu_and_1
 587 #  define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 588 # endif
 589 # ifndef irqsafe_cpu_and_2
 590 #  define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 591 # endif
 592 # ifndef irqsafe_cpu_and_4
 593 #  define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 594 # endif
 595 # ifndef irqsafe_cpu_and_8
 596 #  define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 597 # endif
 598 # define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val))
 599 #endif
 600
 601 #ifndef irqsafe_cpu_or
 602 # ifndef irqsafe_cpu_or_1
 603 #  define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 604 # endif
 605 # ifndef irqsafe_cpu_or_2
 606 #  define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 607 # endif
 608 # ifndef irqsafe_cpu_or_4
 609 #  define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 610 # endif
 611 # ifndef irqsafe_cpu_or_8
 612 #  define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 613 # endif
 614 # define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val))
 615 #endif
 616
 617 #ifndef irqsafe_cpu_xor
 618 # ifndef irqsafe_cpu_xor_1
 619 #  define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 620 # endif
 621 # ifndef irqsafe_cpu_xor_2
 622 #  define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 623 # endif
 624 # ifndef irqsafe_cpu_xor_4
 625 #  define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 626 # endif
 627 # ifndef irqsafe_cpu_xor_8
 628 #  define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 629 # endif
 630 # define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val))
 631 #endif
 632
 633 #endif /* __LINUX_PERCPU_H */