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
 141 #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA
 142 extern void __init setup_per_cpu_areas(void);
 143 #endif
 144
 145 #else /* CONFIG_SMP */
 146
 147 #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
 148
 149 static inline void __percpu *__alloc_percpu(size_t size, size_t align)
 150 {
 151         /*
 152          * Can't easily make larger alignment work with kmalloc.  WARN
 153          * on it.  Larger alignment should only be used for module
 154          * percpu sections on SMP for which this path isn't used.
 155          */
 156         WARN_ON_ONCE(align > SMP_CACHE_BYTES);
 157         return kzalloc(size, GFP_KERNEL);
 158 }
 159
 160 static inline void free_percpu(void __percpu *p)
 161 {
 162         kfree(p);
 163 }
 164
 165 static inline void __init setup_per_cpu_areas(void) { }
 166
 167 static inline void *pcpu_lpage_remapped(void *kaddr)
 168 {
 169         return NULL;
 170 }
 171
 172 #endif /* CONFIG_SMP */
 173
 174 #define alloc_percpu(type)      \
 175         (typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
 176
 177 /*
 178  * Optional methods for optimized non-lvalue per-cpu variable access.
 179  *
 180  * @var can be a percpu variable or a field of it and its size should
 181  * equal char, int or long.  percpu_read() evaluates to a lvalue and
 182  * all others to void.
 183  *
 184  * These operations are guaranteed to be atomic w.r.t. preemption.
 185  * The generic versions use plain get/put_cpu_var().  Archs are
 186  * encouraged to implement single-instruction alternatives which don't
 187  * require preemption protection.
 188  */
 189 #ifndef percpu_read
 190 # define percpu_read(var)                                               \
 191   ({                                                                    \
 192         typeof(var) *pr_ptr__ = &(var);                                 \
 193         typeof(var) pr_ret__;                                           \
 194         pr_ret__ = get_cpu_var(*pr_ptr__);                              \
 195         put_cpu_var(*pr_ptr__);                                         \
 196         pr_ret__;                                                       \
 197   })
 198 #endif
 199
 200 #define __percpu_generic_to_op(var, val, op)                            \
 201 do {                                                                    \
 202         typeof(var) *pgto_ptr__ = &(var);                               \
 203         get_cpu_var(*pgto_ptr__) op val;                                \
 204         put_cpu_var(*pgto_ptr__);                                       \
 205 } while (0)
 206
 207 #ifndef percpu_write
 208 # define percpu_write(var, val)         __percpu_generic_to_op(var, (val), =)
 209 #endif
 210
 211 #ifndef percpu_add
 212 # define percpu_add(var, val)           __percpu_generic_to_op(var, (val), +=)
 213 #endif
 214
 215 #ifndef percpu_sub
 216 # define percpu_sub(var, val)           __percpu_generic_to_op(var, (val), -=)
 217 #endif
 218
 219 #ifndef percpu_and
 220 # define percpu_and(var, val)           __percpu_generic_to_op(var, (val), &=)
 221 #endif
 222
 223 #ifndef percpu_or
 224 # define percpu_or(var, val)            __percpu_generic_to_op(var, (val), |=)
 225 #endif
 226
 227 #ifndef percpu_xor
 228 # define percpu_xor(var, val)           __percpu_generic_to_op(var, (val), ^=)
 229 #endif
 230
 231 /*
 232  * Branching function to split up a function into a set of functions that
 233  * are called for different scalar sizes of the objects handled.
 234  */
 235
 236 extern void __bad_size_call_parameter(void);
 237
 238 #define __pcpu_size_call_return(stem, variable)                         \
 239 ({      typeof(variable) pscr_ret__;                                    \
 240         switch(sizeof(variable)) {                                      \
 241         case 1: pscr_ret__ = stem##1(variable);break;                   \
 242         case 2: pscr_ret__ = stem##2(variable);break;                   \
 243         case 4: pscr_ret__ = stem##4(variable);break;                   \
 244         case 8: pscr_ret__ = stem##8(variable);break;                   \
 245         default:                                                        \
 246                 __bad_size_call_parameter();break;                      \
 247         }                                                               \
 248         pscr_ret__;                                                     \
 249 })
 250
 251 #define __pcpu_size_call(stem, variable, ...)                           \
 252 do {                                                                    \
 253         switch(sizeof(variable)) {                                      \
 254                 case 1: stem##1(variable, __VA_ARGS__);break;           \
 255                 case 2: stem##2(variable, __VA_ARGS__);break;           \
 256                 case 4: stem##4(variable, __VA_ARGS__);break;           \
 257                 case 8: stem##8(variable, __VA_ARGS__);break;           \
 258                 default:                                                \
 259                         __bad_size_call_parameter();break;              \
 260         }                                                               \
 261 } while (0)
 262
 263 /*
 264  * Optimized manipulation for memory allocated through the per cpu
 265  * allocator or for addresses of per cpu variables.
 266  *
 267  * These operation guarantee exclusivity of access for other operations
 268  * on the *same* processor. The assumption is that per cpu data is only
 269  * accessed by a single processor instance (the current one).
 270  *
 271  * The first group is used for accesses that must be done in a
 272  * preemption safe way since we know that the context is not preempt
 273  * safe. Interrupts may occur. If the interrupt modifies the variable
 274  * too then RMW actions will not be reliable.
 275  *
 276  * The arch code can provide optimized functions in two ways:
 277  *
 278  * 1. Override the function completely. F.e. define this_cpu_add().
 279  *    The arch must then ensure that the various scalar format passed
 280  *    are handled correctly.
 281  *
 282  * 2. Provide functions for certain scalar sizes. F.e. provide
 283  *    this_cpu_add_2() to provide per cpu atomic operations for 2 byte
 284  *    sized RMW actions. If arch code does not provide operations for
 285  *    a scalar size then the fallback in the generic code will be
 286  *    used.
 287  */
 288
 289 #define _this_cpu_generic_read(pcp)                                     \
 290 ({      typeof(pcp) ret__;                                              \
 291         preempt_disable();                                              \
 292         ret__ = *this_cpu_ptr(&(pcp));                                  \
 293         preempt_enable();                                               \
 294         ret__;                                                          \
 295 })
 296
 297 #ifndef this_cpu_read
 298 # ifndef this_cpu_read_1
 299 #  define this_cpu_read_1(pcp)  _this_cpu_generic_read(pcp)
 300 # endif
 301 # ifndef this_cpu_read_2
 302 #  define this_cpu_read_2(pcp)  _this_cpu_generic_read(pcp)
 303 # endif
 304 # ifndef this_cpu_read_4
 305 #  define this_cpu_read_4(pcp)  _this_cpu_generic_read(pcp)
 306 # endif
 307 # ifndef this_cpu_read_8
 308 #  define this_cpu_read_8(pcp)  _this_cpu_generic_read(pcp)
 309 # endif
 310 # define this_cpu_read(pcp)     __pcpu_size_call_return(this_cpu_read_, (pcp))
 311 #endif
 312
 313 #define _this_cpu_generic_to_op(pcp, val, op)                           \
 314 do {                                                                    \
 315         preempt_disable();                                              \
 316         *__this_cpu_ptr(&(pcp)) op val;                                 \
 317         preempt_enable();                                               \
 318 } while (0)
 319
 320 #ifndef this_cpu_write
 321 # ifndef this_cpu_write_1
 322 #  define this_cpu_write_1(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 323 # endif
 324 # ifndef this_cpu_write_2
 325 #  define this_cpu_write_2(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 326 # endif
 327 # ifndef this_cpu_write_4
 328 #  define this_cpu_write_4(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 329 # endif
 330 # ifndef this_cpu_write_8
 331 #  define this_cpu_write_8(pcp, val)    _this_cpu_generic_to_op((pcp), (val), =)
 332 # endif
 333 # define this_cpu_write(pcp, val)       __pcpu_size_call(this_cpu_write_, (pcp), (val))
 334 #endif
 335
 336 #ifndef this_cpu_add
 337 # ifndef this_cpu_add_1
 338 #  define this_cpu_add_1(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 339 # endif
 340 # ifndef this_cpu_add_2
 341 #  define this_cpu_add_2(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 342 # endif
 343 # ifndef this_cpu_add_4
 344 #  define this_cpu_add_4(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 345 # endif
 346 # ifndef this_cpu_add_8
 347 #  define this_cpu_add_8(pcp, val)      _this_cpu_generic_to_op((pcp), (val), +=)
 348 # endif
 349 # define this_cpu_add(pcp, val)         __pcpu_size_call(this_cpu_add_, (pcp), (val))
 350 #endif
 351
 352 #ifndef this_cpu_sub
 353 # define this_cpu_sub(pcp, val)         this_cpu_add((pcp), -(val))
 354 #endif
 355
 356 #ifndef this_cpu_inc
 357 # define this_cpu_inc(pcp)              this_cpu_add((pcp), 1)
 358 #endif
 359
 360 #ifndef this_cpu_dec
 361 # define this_cpu_dec(pcp)              this_cpu_sub((pcp), 1)
 362 #endif
 363
 364 #ifndef this_cpu_and
 365 # ifndef this_cpu_and_1
 366 #  define this_cpu_and_1(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 367 # endif
 368 # ifndef this_cpu_and_2
 369 #  define this_cpu_and_2(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 370 # endif
 371 # ifndef this_cpu_and_4
 372 #  define this_cpu_and_4(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 373 # endif
 374 # ifndef this_cpu_and_8
 375 #  define this_cpu_and_8(pcp, val)      _this_cpu_generic_to_op((pcp), (val), &=)
 376 # endif
 377 # define this_cpu_and(pcp, val)         __pcpu_size_call(this_cpu_and_, (pcp), (val))
 378 #endif
 379
 380 #ifndef this_cpu_or
 381 # ifndef this_cpu_or_1
 382 #  define this_cpu_or_1(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 383 # endif
 384 # ifndef this_cpu_or_2
 385 #  define this_cpu_or_2(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 386 # endif
 387 # ifndef this_cpu_or_4
 388 #  define this_cpu_or_4(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 389 # endif
 390 # ifndef this_cpu_or_8
 391 #  define this_cpu_or_8(pcp, val)       _this_cpu_generic_to_op((pcp), (val), |=)
 392 # endif
 393 # define this_cpu_or(pcp, val)          __pcpu_size_call(this_cpu_or_, (pcp), (val))
 394 #endif
 395
 396 #ifndef this_cpu_xor
 397 # ifndef this_cpu_xor_1
 398 #  define this_cpu_xor_1(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 399 # endif
 400 # ifndef this_cpu_xor_2
 401 #  define this_cpu_xor_2(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 402 # endif
 403 # ifndef this_cpu_xor_4
 404 #  define this_cpu_xor_4(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 405 # endif
 406 # ifndef this_cpu_xor_8
 407 #  define this_cpu_xor_8(pcp, val)      _this_cpu_generic_to_op((pcp), (val), ^=)
 408 # endif
 409 # define this_cpu_xor(pcp, val)         __pcpu_size_call(this_cpu_or_, (pcp), (val))
 410 #endif
 411
 412 /*
 413  * Generic percpu operations that do not require preemption handling.
 414  * Either we do not care about races or the caller has the
 415  * responsibility of handling preemptions issues. Arch code can still
 416  * override these instructions since the arch per cpu code may be more
 417  * efficient and may actually get race freeness for free (that is the
 418  * case for x86 for example).
 419  *
 420  * If there is no other protection through preempt disable and/or
 421  * disabling interupts then one of these RMW operations can show unexpected
 422  * behavior because the execution thread was rescheduled on another processor
 423  * or an interrupt occurred and the same percpu variable was modified from
 424  * the interrupt context.
 425  */
 426 #ifndef __this_cpu_read
 427 # ifndef __this_cpu_read_1
 428 #  define __this_cpu_read_1(pcp)        (*__this_cpu_ptr(&(pcp)))
 429 # endif
 430 # ifndef __this_cpu_read_2
 431 #  define __this_cpu_read_2(pcp)        (*__this_cpu_ptr(&(pcp)))
 432 # endif
 433 # ifndef __this_cpu_read_4
 434 #  define __this_cpu_read_4(pcp)        (*__this_cpu_ptr(&(pcp)))
 435 # endif
 436 # ifndef __this_cpu_read_8
 437 #  define __this_cpu_read_8(pcp)        (*__this_cpu_ptr(&(pcp)))
 438 # endif
 439 # define __this_cpu_read(pcp)   __pcpu_size_call_return(__this_cpu_read_, (pcp))
 440 #endif
 441
 442 #define __this_cpu_generic_to_op(pcp, val, op)                          \
 443 do {                                                                    \
 444         *__this_cpu_ptr(&(pcp)) op val;                                 \
 445 } while (0)
 446
 447 #ifndef __this_cpu_write
 448 # ifndef __this_cpu_write_1
 449 #  define __this_cpu_write_1(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 450 # endif
 451 # ifndef __this_cpu_write_2
 452 #  define __this_cpu_write_2(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 453 # endif
 454 # ifndef __this_cpu_write_4
 455 #  define __this_cpu_write_4(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 456 # endif
 457 # ifndef __this_cpu_write_8
 458 #  define __this_cpu_write_8(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 459 # endif
 460 # define __this_cpu_write(pcp, val)     __pcpu_size_call(__this_cpu_write_, (pcp), (val))
 461 #endif
 462
 463 #ifndef __this_cpu_add
 464 # ifndef __this_cpu_add_1
 465 #  define __this_cpu_add_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 466 # endif
 467 # ifndef __this_cpu_add_2
 468 #  define __this_cpu_add_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 469 # endif
 470 # ifndef __this_cpu_add_4
 471 #  define __this_cpu_add_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 472 # endif
 473 # ifndef __this_cpu_add_8
 474 #  define __this_cpu_add_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 475 # endif
 476 # define __this_cpu_add(pcp, val)       __pcpu_size_call(__this_cpu_add_, (pcp), (val))
 477 #endif
 478
 479 #ifndef __this_cpu_sub
 480 # define __this_cpu_sub(pcp, val)       __this_cpu_add((pcp), -(val))
 481 #endif
 482
 483 #ifndef __this_cpu_inc
 484 # define __this_cpu_inc(pcp)            __this_cpu_add((pcp), 1)
 485 #endif
 486
 487 #ifndef __this_cpu_dec
 488 # define __this_cpu_dec(pcp)            __this_cpu_sub((pcp), 1)
 489 #endif
 490
 491 #ifndef __this_cpu_and
 492 # ifndef __this_cpu_and_1
 493 #  define __this_cpu_and_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 494 # endif
 495 # ifndef __this_cpu_and_2
 496 #  define __this_cpu_and_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 497 # endif
 498 # ifndef __this_cpu_and_4
 499 #  define __this_cpu_and_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 500 # endif
 501 # ifndef __this_cpu_and_8
 502 #  define __this_cpu_and_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 503 # endif
 504 # define __this_cpu_and(pcp, val)       __pcpu_size_call(__this_cpu_and_, (pcp), (val))
 505 #endif
 506
 507 #ifndef __this_cpu_or
 508 # ifndef __this_cpu_or_1
 509 #  define __this_cpu_or_1(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 510 # endif
 511 # ifndef __this_cpu_or_2
 512 #  define __this_cpu_or_2(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 513 # endif
 514 # ifndef __this_cpu_or_4
 515 #  define __this_cpu_or_4(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 516 # endif
 517 # ifndef __this_cpu_or_8
 518 #  define __this_cpu_or_8(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 519 # endif
 520 # define __this_cpu_or(pcp, val)        __pcpu_size_call(__this_cpu_or_, (pcp), (val))
 521 #endif
 522
 523 #ifndef __this_cpu_xor
 524 # ifndef __this_cpu_xor_1
 525 #  define __this_cpu_xor_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 526 # endif
 527 # ifndef __this_cpu_xor_2
 528 #  define __this_cpu_xor_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 529 # endif
 530 # ifndef __this_cpu_xor_4
 531 #  define __this_cpu_xor_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 532 # endif
 533 # ifndef __this_cpu_xor_8
 534 #  define __this_cpu_xor_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 535 # endif
 536 # define __this_cpu_xor(pcp, val)       __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
 537 #endif
 538
 539 /*
 540  * IRQ safe versions of the per cpu RMW operations. Note that these operations
 541  * are *not* safe against modification of the same variable from another
 542  * processors (which one gets when using regular atomic operations)
 543  . They are guaranteed to be atomic vs. local interrupts and
 544  * preemption only.
 545  */
 546 #define irqsafe_cpu_generic_to_op(pcp, val, op)                         \
 547 do {                                                                    \
 548         unsigned long flags;                                            \
 549         local_irq_save(flags);                                          \
 550         *__this_cpu_ptr(&(pcp)) op val;                                 \
 551         local_irq_restore(flags);                                       \
 552 } while (0)
 553
 554 #ifndef irqsafe_cpu_add
 555 # ifndef irqsafe_cpu_add_1
 556 #  define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 557 # endif
 558 # ifndef irqsafe_cpu_add_2
 559 #  define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 560 # endif
 561 # ifndef irqsafe_cpu_add_4
 562 #  define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 563 # endif
 564 # ifndef irqsafe_cpu_add_8
 565 #  define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 566 # endif
 567 # define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val))
 568 #endif
 569
 570 #ifndef irqsafe_cpu_sub
 571 # define irqsafe_cpu_sub(pcp, val)      irqsafe_cpu_add((pcp), -(val))
 572 #endif
 573
 574 #ifndef irqsafe_cpu_inc
 575 # define irqsafe_cpu_inc(pcp)   irqsafe_cpu_add((pcp), 1)
 576 #endif
 577
 578 #ifndef irqsafe_cpu_dec
 579 # define irqsafe_cpu_dec(pcp)   irqsafe_cpu_sub((pcp), 1)
 580 #endif
 581
 582 #ifndef irqsafe_cpu_and
 583 # ifndef irqsafe_cpu_and_1
 584 #  define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 585 # endif
 586 # ifndef irqsafe_cpu_and_2
 587 #  define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 588 # endif
 589 # ifndef irqsafe_cpu_and_4
 590 #  define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 591 # endif
 592 # ifndef irqsafe_cpu_and_8
 593 #  define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 594 # endif
 595 # define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val))
 596 #endif
 597
 598 #ifndef irqsafe_cpu_or
 599 # ifndef irqsafe_cpu_or_1
 600 #  define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 601 # endif
 602 # ifndef irqsafe_cpu_or_2
 603 #  define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 604 # endif
 605 # ifndef irqsafe_cpu_or_4
 606 #  define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 607 # endif
 608 # ifndef irqsafe_cpu_or_8
 609 #  define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 610 # endif
 611 # define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val))
 612 #endif
 613
 614 #ifndef irqsafe_cpu_xor
 615 # ifndef irqsafe_cpu_xor_1
 616 #  define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 617 # endif
 618 # ifndef irqsafe_cpu_xor_2
 619 #  define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 620 # endif
 621 # ifndef irqsafe_cpu_xor_4
 622 #  define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 623 # endif
 624 # ifndef irqsafe_cpu_xor_8
 625 #  define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 626 # endif
 627 # define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val))
 628 #endif
 629
 630 #endif /* __LINUX_PERCPU_H */