include/linux/percpu.h

   1 #ifndef __LINUX_PERCPU_H
   2 #define __LINUX_PERCPU_H
   3
   4 #include <linux/preempt.h>
   5 #include <linux/slab.h> /* For kmalloc() */
   6 #include <linux/smp.h>
   7 #include <linux/cpumask.h>
   8 #include <linux/pfn.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_DYNAMIC_RESERVE indicates the amount of free area to piggy
  49  * back on the first chunk for dynamic percpu allocation if arch is
  50  * manually allocating and mapping it for faster access (as a part of
  51  * large page mapping for example).
  52  *
  53  * The following values give between one and two pages of free space
  54  * after typical minimal boot (2-way SMP, single disk and NIC) with
  55  * both defconfig and a distro config on x86_64 and 32.  More
  56  * intelligent way to determine this would be nice.
  57  */
  58 #if BITS_PER_LONG > 32
  59 #define PERCPU_DYNAMIC_RESERVE          (20 << 10)
  60 #else
  61 #define PERCPU_DYNAMIC_RESERVE          (12 << 10)
  62 #endif
  63
  64 extern void *pcpu_base_addr;
  65 extern const unsigned long *pcpu_unit_offsets;
  66
  67 struct pcpu_group_info {
  68         int                     nr_units;       /* aligned # of units */
  69         unsigned long           base_offset;    /* base address offset */
  70         unsigned int            *cpu_map;       /* unit->cpu map, empty
  71                                                  * entries contain NR_CPUS */
  72 };
  73
  74 struct pcpu_alloc_info {
  75         size_t                  static_size;
  76         size_t                  reserved_size;
  77         size_t                  dyn_size;
  78         size_t                  unit_size;
  79         size_t                  atom_size;
  80         size_t                  alloc_size;
  81         size_t                  __ai_size;      /* internal, don't use */
  82         int                     nr_groups;      /* 0 if grouping unnecessary */
  83         struct pcpu_group_info  groups[];
  84 };
  85
  86 enum pcpu_fc {
  87         PCPU_FC_AUTO,
  88         PCPU_FC_EMBED,
  89         PCPU_FC_PAGE,
  90
  91         PCPU_FC_NR,
  92 };
  93 extern const char *pcpu_fc_names[PCPU_FC_NR];
  94
  95 extern enum pcpu_fc pcpu_chosen_fc;
  96
  97 typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
  98                                      size_t align);
  99 typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
 100 typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
 101 typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
 102
 103 extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
 104                                                              int nr_units);
 105 extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
 106
 107 extern struct pcpu_alloc_info * __init pcpu_build_alloc_info(
 108                                 size_t reserved_size, ssize_t dyn_size,
 109                                 size_t atom_size,
 110                                 pcpu_fc_cpu_distance_fn_t cpu_distance_fn);
 111
 112 extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
 113                                          void *base_addr);
 114
 115 #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
 116 extern int __init pcpu_embed_first_chunk(size_t reserved_size, ssize_t dyn_size,
 117                                 size_t atom_size,
 118                                 pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
 119                                 pcpu_fc_alloc_fn_t alloc_fn,
 120                                 pcpu_fc_free_fn_t free_fn);
 121 #endif
 122
 123 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
 124 extern int __init pcpu_page_first_chunk(size_t reserved_size,
 125                                 pcpu_fc_alloc_fn_t alloc_fn,
 126                                 pcpu_fc_free_fn_t free_fn,
 127                                 pcpu_fc_populate_pte_fn_t populate_pte_fn);
 128 #endif
 129
 130 /*
 131  * Use this to get to a cpu's version of the per-cpu object
 132  * dynamically allocated. Non-atomic access to the current CPU's
 133  * version should probably be combined with get_cpu()/put_cpu().
 134  */
 135 #define per_cpu_ptr(ptr, cpu)   SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
 136
 137 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
 138 extern void __percpu *__alloc_percpu(size_t size, size_t align);
 139 extern void free_percpu(void __percpu *__pdata);
 140 extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
 141
 142 #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
 143 extern void __init setup_per_cpu_areas(void);
 144 #endif
 145
 146 #else /* CONFIG_SMP */
 147
 148 #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
 149
 150 static inline void __percpu *__alloc_percpu(size_t size, size_t align)
 151 {
 152         /*
 153          * Can't easily make larger alignment work with kmalloc.  WARN
 154          * on it.  Larger alignment should only be used for module
 155          * percpu sections on SMP for which this path isn't used.
 156          */
 157         WARN_ON_ONCE(align > SMP_CACHE_BYTES);
 158         return kzalloc(size, GFP_KERNEL);
 159 }
 160
 161 static inline void free_percpu(void __percpu *p)
 162 {
 163         kfree(p);
 164 }
 165
 166 static inline phys_addr_t per_cpu_ptr_to_phys(void *addr)
 167 {
 168         return __pa(addr);
 169 }
 170
 171 static inline void __init setup_per_cpu_areas(void) { }
 172
 173 static inline void *pcpu_lpage_remapped(void *kaddr)
 174 {
 175         return NULL;
 176 }
 177
 178 #endif /* CONFIG_SMP */
 179
 180 #define alloc_percpu(type)      \
 181         (typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
 182
 183 /*
 184  * Optional methods for optimized non-lvalue per-cpu variable access.
 185  *
 186  * @var can be a percpu variable or a field of it and its size should
 187  * equal char, int or long.  percpu_read() evaluates to a lvalue and
 188  * all others to void.
 189  *
 190  * These operations are guaranteed to be atomic w.r.t. preemption.
 191  * The generic versions use plain get/put_cpu_var().  Archs are
 192  * encouraged to implement single-instruction alternatives which don't
 193  * require preemption protection.
 194  */
 195 #ifndef percpu_read
 196 # define percpu_read(var)                                               \
 197   ({                                                                    \
 198         typeof(var) *pr_ptr__ = &(var);                                 \
 199         typeof(var) pr_ret__;                                           \
 200         pr_ret__ = get_cpu_var(*pr_ptr__);                              \
 201         put_cpu_var(*pr_ptr__);                                         \
 202         pr_ret__;                                                       \
 203   })
 204 #endif
 205
 206 #define __percpu_generic_to_op(var, val, op)                            \
 207 do {                                                                    \
 208         typeof(var) *pgto_ptr__ = &(var);                               \
 209         get_cpu_var(*pgto_ptr__) op val;                                \
 210         put_cpu_var(*pgto_ptr__);                                       \
 211 } while (0)
 212
 213 #ifndef percpu_write
 214 # define percpu_write(var, val)         __percpu_generic_to_op(var, (val), =)
 215 #endif
 216
 217 #ifndef percpu_add
 218 # define percpu_add(var, val)           __percpu_generic_to_op(var, (val), +=)
 219 #endif
 220
 221 #ifndef percpu_sub
 222 # define percpu_sub(var, val)           __percpu_generic_to_op(var, (val), -=)
 223 #endif
 224
 225 #ifndef percpu_and
 226 # define percpu_and(var, val)           __percpu_generic_to_op(var, (val), &=)
 227 #endif
 228
 229 #ifndef percpu_or
 230 # define percpu_or(var, val)            __percpu_generic_to_op(var, (val), |=)
 231 #endif
 232
 233 #ifndef percpu_xor
 234 # define percpu_xor(var, val)           __percpu_generic_to_op(var, (val), ^=)
 235 #endif
 236
 237 /*
 238  * Branching function to split up a function into a set of functions that
 239  * are called for different scalar sizes of the objects handled.
 240  */
 241
 242 extern void __bad_size_call_parameter(void);
 243
 244 #define __pcpu_size_call_return(stem, variable)                         \
 245 ({      typeof(variable) pscr_ret__;                                    \
 246         __verify_pcpu_ptr(&(variable));                                 \
 247         switch(sizeof(variable)) {                                      \
 248         case 1: pscr_ret__ = stem##1(variable);break;                   \
 249         case 2: pscr_ret__ = stem##2(variable);break;                   \
 250         case 4: pscr_ret__ = stem##4(variable);break;                   \
 251         case 8: pscr_ret__ = stem##8(variable);break;                   \
 252         default:                                                        \
 253                 __bad_size_call_parameter();break;                      \
 254         }                                                               \
 255         pscr_ret__;                                                     \
 256 })
 257
 258 #define __pcpu_size_call(stem, variable, ...)                           \
 259 do {                                                                    \
 260         __verify_pcpu_ptr(&(variable));                                 \
 261         switch(sizeof(variable)) {                                      \
 262                 case 1: stem##1(variable, __VA_ARGS__);break;           \
 263                 case 2: stem##2(variable, __VA_ARGS__);break;           \
 264                 case 4: stem##4(variable, __VA_ARGS__);break;           \
 265                 case 8: stem##8(variable, __VA_ARGS__);break;           \
 266                 default:                                                \
 267                         __bad_size_call_parameter();break;              \
 268         }                                                               \
 269 } while (0)
 270
 271 /*
 272  * Optimized manipulation for memory allocated through the per cpu
 273  * allocator or for addresses of per cpu variables.
 274  *
 275  * These operation guarantee exclusivity of access for other operations
 276  * on the *same* processor. The assumption is that per cpu data is only
 277  * accessed by a single processor instance (the current one).
 278  *
 279  * The first group is used for accesses that must be done in a
 280  * preemption safe way since we know that the context is not preempt
 281  * safe. Interrupts may occur. If the interrupt modifies the variable
 282  * too then RMW actions will not be reliable.
 283  *
 284  * The arch code can provide optimized functions in two ways:
 285  *
 286  * 1. Override the function completely. F.e. define this_cpu_add().
 287  *    The arch must then ensure that the various scalar format passed
 288  *    are handled correctly.
 289  *
 290  * 2. Provide functions for certain scalar sizes. F.e. provide
 291  *    this_cpu_add_2() to provide per cpu atomic operations for 2 byte
 292  *    sized RMW actions. If arch code does not provide operations for
 293  *    a scalar size then the fallback in the generic code will be
 294  *    used.
 295  */
 296
 297 #define _this_cpu_generic_read(pcp)                                     \
 298 ({      typeof(pcp) ret__;                                              \
 299         preempt_disable();                                              \
 300         ret__ = *this_cpu_ptr(&(pcp));                                  \
 301         preempt_enable();                                               \
 302         ret__;                                                          \
 303 })
 304
 305 #ifndef this_cpu_read
 306 # ifndef this_cpu_read_1
 307 #  define this_cpu_read_1(pcp)  _this_cpu_generic_read(pcp)
 308 # endif
 309 # ifndef this_cpu_read_2
 310 #  define this_cpu_read_2(pcp)  _this_cpu_generic_read(pcp)
 311 # endif
 312 # ifndef this_cpu_read_4
 313 #  define this_cpu_read_4(pcp)  _this_cpu_generic_read(pcp)
 314 # endif
 315 # ifndef this_cpu_read_8
 316 #  define this_cpu_read_8(pcp)  _this_cpu_generic_read(pcp)
 317 # endif
 318 # define this_cpu_read(pcp)     __pcpu_size_call_return(this_cpu_read_, (pcp))
 319 #endif
 320
 321 #define _this_cpu_generic_to_op(pcp, val, op)                           \
 322 do {                                                                    \
 323         preempt_disable();                                              \
 324         *__this_cpu_ptr(&(pcp)) op val;                                 \
 325         preempt_enable();                                               \
 326 } while (0)
 327
 328 #ifndef this_cpu_write
 329 # ifndef this_cpu_write_1
 330 #  define this_cpu_write_1(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 331 # endif
 332 # ifndef this_cpu_write_2
 333 #  define this_cpu_write_2(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 334 # endif
 335 # ifndef this_cpu_write_4
 336 #  define this_cpu_write_4(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 337 # endif
 338 # ifndef this_cpu_write_8
 339 #  define this_cpu_write_8(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 340 # endif
 341 # define this_cpu_write(pcp, val)       __pcpu_size_call(this_cpu_write_, (pcp), (val))
 342 #endif
 343
 344 #ifndef this_cpu_add
 345 # ifndef this_cpu_add_1
 346 #  define this_cpu_add_1(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 347 # endif
 348 # ifndef this_cpu_add_2
 349 #  define this_cpu_add_2(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 350 # endif
 351 # ifndef this_cpu_add_4
 352 #  define this_cpu_add_4(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 353 # endif
 354 # ifndef this_cpu_add_8
 355 #  define this_cpu_add_8(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 356 # endif
 357 # define this_cpu_add(pcp, val)         __pcpu_size_call(this_cpu_add_, (pcp), (val))
 358 #endif
 359
 360 #ifndef this_cpu_sub
 361 # define this_cpu_sub(pcp, val)         this_cpu_add((pcp), -(val))
 362 #endif
 363
 364 #ifndef this_cpu_inc
 365 # define this_cpu_inc(pcp)              this_cpu_add((pcp), 1)
 366 #endif
 367
 368 #ifndef this_cpu_dec
 369 # define this_cpu_dec(pcp)              this_cpu_sub((pcp), 1)
 370 #endif
 371
 372 #ifndef this_cpu_and
 373 # ifndef this_cpu_and_1
 374 #  define this_cpu_and_1(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 375 # endif
 376 # ifndef this_cpu_and_2
 377 #  define this_cpu_and_2(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 378 # endif
 379 # ifndef this_cpu_and_4
 380 #  define this_cpu_and_4(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 381 # endif
 382 # ifndef this_cpu_and_8
 383 #  define this_cpu_and_8(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 384 # endif
 385 # define this_cpu_and(pcp, val)         __pcpu_size_call(this_cpu_and_, (pcp), (val))
 386 #endif
 387
 388 #ifndef this_cpu_or
 389 # ifndef this_cpu_or_1
 390 #  define this_cpu_or_1(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 391 # endif
 392 # ifndef this_cpu_or_2
 393 #  define this_cpu_or_2(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 394 # endif
 395 # ifndef this_cpu_or_4
 396 #  define this_cpu_or_4(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 397 # endif
 398 # ifndef this_cpu_or_8
 399 #  define this_cpu_or_8(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 400 # endif
 401 # define this_cpu_or(pcp, val)          __pcpu_size_call(this_cpu_or_, (pcp), (val))
 402 #endif
 403
 404 #ifndef this_cpu_xor
 405 # ifndef this_cpu_xor_1
 406 #  define this_cpu_xor_1(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 407 # endif
 408 # ifndef this_cpu_xor_2
 409 #  define this_cpu_xor_2(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 410 # endif
 411 # ifndef this_cpu_xor_4
 412 #  define this_cpu_xor_4(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 413 # endif
 414 # ifndef this_cpu_xor_8
 415 #  define this_cpu_xor_8(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 416 # endif
 417 # define this_cpu_xor(pcp, val)         __pcpu_size_call(this_cpu_or_, (pcp), (val))
 418 #endif
 419
 420 /*
 421  * Generic percpu operations that do not require preemption handling.
 422  * Either we do not care about races or the caller has the
 423  * responsibility of handling preemptions issues. Arch code can still
 424  * override these instructions since the arch per cpu code may be more
 425  * efficient and may actually get race freeness for free (that is the
 426  * case for x86 for example).
 427  *
 428  * If there is no other protection through preempt disable and/or
 429  * disabling interupts then one of these RMW operations can show unexpected
 430  * behavior because the execution thread was rescheduled on another processor
 431  * or an interrupt occurred and the same percpu variable was modified from
 432  * the interrupt context.
 433  */
 434 #ifndef __this_cpu_read
 435 # ifndef __this_cpu_read_1
 436 #  define __this_cpu_read_1(pcp)        (*__this_cpu_ptr(&(pcp)))
 437 # endif
 438 # ifndef __this_cpu_read_2
 439 #  define __this_cpu_read_2(pcp)        (*__this_cpu_ptr(&(pcp)))
 440 # endif
 441 # ifndef __this_cpu_read_4
 442 #  define __this_cpu_read_4(pcp)        (*__this_cpu_ptr(&(pcp)))
 443 # endif
 444 # ifndef __this_cpu_read_8
 445 #  define __this_cpu_read_8(pcp)        (*__this_cpu_ptr(&(pcp)))
 446 # endif
 447 # define __this_cpu_read(pcp)   __pcpu_size_call_return(__this_cpu_read_, (pcp))
 448 #endif
 449
 450 #define __this_cpu_generic_to_op(pcp, val, op)                          \
 451 do {                                                                    \
 452         *__this_cpu_ptr(&(pcp)) op val;                                 \
 453 } while (0)
 454
 455 #ifndef __this_cpu_write
 456 # ifndef __this_cpu_write_1
 457 #  define __this_cpu_write_1(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 458 # endif
 459 # ifndef __this_cpu_write_2
 460 #  define __this_cpu_write_2(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 461 # endif
 462 # ifndef __this_cpu_write_4
 463 #  define __this_cpu_write_4(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 464 # endif
 465 # ifndef __this_cpu_write_8
 466 #  define __this_cpu_write_8(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 467 # endif
 468 # define __this_cpu_write(pcp, val)     __pcpu_size_call(__this_cpu_write_, (pcp), (val))
 469 #endif
 470
 471 #ifndef __this_cpu_add
 472 # ifndef __this_cpu_add_1
 473 #  define __this_cpu_add_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 474 # endif
 475 # ifndef __this_cpu_add_2
 476 #  define __this_cpu_add_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 477 # endif
 478 # ifndef __this_cpu_add_4
 479 #  define __this_cpu_add_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 480 # endif
 481 # ifndef __this_cpu_add_8
 482 #  define __this_cpu_add_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 483 # endif
 484 # define __this_cpu_add(pcp, val)       __pcpu_size_call(__this_cpu_add_, (pcp), (val))
 485 #endif
 486
 487 #ifndef __this_cpu_sub
 488 # define __this_cpu_sub(pcp, val)       __this_cpu_add((pcp), -(val))
 489 #endif
 490
 491 #ifndef __this_cpu_inc
 492 # define __this_cpu_inc(pcp)            __this_cpu_add((pcp), 1)
 493 #endif
 494
 495 #ifndef __this_cpu_dec
 496 # define __this_cpu_dec(pcp)            __this_cpu_sub((pcp), 1)
 497 #endif
 498
 499 #ifndef __this_cpu_and
 500 # ifndef __this_cpu_and_1
 501 #  define __this_cpu_and_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 502 # endif
 503 # ifndef __this_cpu_and_2
 504 #  define __this_cpu_and_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 505 # endif
 506 # ifndef __this_cpu_and_4
 507 #  define __this_cpu_and_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 508 # endif
 509 # ifndef __this_cpu_and_8
 510 #  define __this_cpu_and_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 511 # endif
 512 # define __this_cpu_and(pcp, val)       __pcpu_size_call(__this_cpu_and_, (pcp), (val))
 513 #endif
 514
 515 #ifndef __this_cpu_or
 516 # ifndef __this_cpu_or_1
 517 #  define __this_cpu_or_1(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 518 # endif
 519 # ifndef __this_cpu_or_2
 520 #  define __this_cpu_or_2(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 521 # endif
 522 # ifndef __this_cpu_or_4
 523 #  define __this_cpu_or_4(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 524 # endif
 525 # ifndef __this_cpu_or_8
 526 #  define __this_cpu_or_8(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 527 # endif
 528 # define __this_cpu_or(pcp, val)        __pcpu_size_call(__this_cpu_or_, (pcp), (val))
 529 #endif
 530
 531 #ifndef __this_cpu_xor
 532 # ifndef __this_cpu_xor_1
 533 #  define __this_cpu_xor_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 534 # endif
 535 # ifndef __this_cpu_xor_2
 536 #  define __this_cpu_xor_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 537 # endif
 538 # ifndef __this_cpu_xor_4
 539 #  define __this_cpu_xor_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 540 # endif
 541 # ifndef __this_cpu_xor_8
 542 #  define __this_cpu_xor_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 543 # endif
 544 # define __this_cpu_xor(pcp, val)       __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
 545 #endif
 546
 547 /*
 548  * IRQ safe versions of the per cpu RMW operations. Note that these operations
 549  * are *not* safe against modification of the same variable from another
 550  * processors (which one gets when using regular atomic operations)
 551  . They are guaranteed to be atomic vs. local interrupts and
 552  * preemption only.
 553  */
 554 #define irqsafe_cpu_generic_to_op(pcp, val, op)                         \
 555 do {                                                                    \
 556         unsigned long flags;                                            \
 557         local_irq_save(flags);                                          \
 558         *__this_cpu_ptr(&(pcp)) op val;                                 \
 559         local_irq_restore(flags);                                       \
 560 } while (0)
 561
 562 #ifndef irqsafe_cpu_add
 563 # ifndef irqsafe_cpu_add_1
 564 #  define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 565 # endif
 566 # ifndef irqsafe_cpu_add_2
 567 #  define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 568 # endif
 569 # ifndef irqsafe_cpu_add_4
 570 #  define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 571 # endif
 572 # ifndef irqsafe_cpu_add_8
 573 #  define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 574 # endif
 575 # define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val))
 576 #endif
 577
 578 #ifndef irqsafe_cpu_sub
 579 # define irqsafe_cpu_sub(pcp, val)      irqsafe_cpu_add((pcp), -(val))
 580 #endif
 581
 582 #ifndef irqsafe_cpu_inc
 583 # define irqsafe_cpu_inc(pcp)   irqsafe_cpu_add((pcp), 1)
 584 #endif
 585
 586 #ifndef irqsafe_cpu_dec
 587 # define irqsafe_cpu_dec(pcp)   irqsafe_cpu_sub((pcp), 1)
 588 #endif
 589
 590 #ifndef irqsafe_cpu_and
 591 # ifndef irqsafe_cpu_and_1
 592 #  define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 593 # endif
 594 # ifndef irqsafe_cpu_and_2
 595 #  define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 596 # endif
 597 # ifndef irqsafe_cpu_and_4
 598 #  define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 599 # endif
 600 # ifndef irqsafe_cpu_and_8
 601 #  define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 602 # endif
 603 # define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val))
 604 #endif
 605
 606 #ifndef irqsafe_cpu_or
 607 # ifndef irqsafe_cpu_or_1
 608 #  define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 609 # endif
 610 # ifndef irqsafe_cpu_or_2
 611 #  define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 612 # endif
 613 # ifndef irqsafe_cpu_or_4
 614 #  define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 615 # endif
 616 # ifndef irqsafe_cpu_or_8
 617 #  define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 618 # endif
 619 # define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val))
 620 #endif
 621
 622 #ifndef irqsafe_cpu_xor
 623 # ifndef irqsafe_cpu_xor_1
 624 #  define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 625 # endif
 626 # ifndef irqsafe_cpu_xor_2
 627 #  define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 628 # endif
 629 # ifndef irqsafe_cpu_xor_4
 630 #  define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 631 # endif
 632 # ifndef irqsafe_cpu_xor_8
 633 #  define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 634 # endif
 635 # define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val))
 636 #endif
 637
 638 #endif /* __LINUX_PERCPU_H */