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 #define get_cpu_ptr(var) ({                             \
  43         preempt_disable();                              \
  44         this_cpu_ptr(var); })
  45
  46 #define put_cpu_ptr(var) do {                           \
  47         (void)(var);                                    \
  48         preempt_enable();                               \
  49 } while (0)
  50
  51 /* minimum unit size, also is the maximum supported allocation size */
  52 #define PCPU_MIN_UNIT_SIZE              PFN_ALIGN(32 << 10)
  53
  54 /*
  55  * Percpu allocator can serve percpu allocations before slab is
  56  * initialized which allows slab to depend on the percpu allocator.
  57  * The following two parameters decide how much resource to
  58  * preallocate for this.  Keep PERCPU_DYNAMIC_RESERVE equal to or
  59  * larger than PERCPU_DYNAMIC_EARLY_SIZE.
  60  */
  61 #define PERCPU_DYNAMIC_EARLY_SLOTS      128
  62 #define PERCPU_DYNAMIC_EARLY_SIZE       (12 << 10)
  63
  64 /*
  65  * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
  66  * back on the first chunk for dynamic percpu allocation if arch is
  67  * manually allocating and mapping it for faster access (as a part of
  68  * large page mapping for example).
  69  *
  70  * The following values give between one and two pages of free space
  71  * after typical minimal boot (2-way SMP, single disk and NIC) with
  72  * both defconfig and a distro config on x86_64 and 32.  More
  73  * intelligent way to determine this would be nice.
  74  */
  75 #if BITS_PER_LONG > 32
  76 #define PERCPU_DYNAMIC_RESERVE          (20 << 10)
  77 #else
  78 #define PERCPU_DYNAMIC_RESERVE          (12 << 10)
  79 #endif
  80
  81 extern void *pcpu_base_addr;
  82 extern const unsigned long *pcpu_unit_offsets;
  83
  84 struct pcpu_group_info {
  85         int                     nr_units;       /* aligned # of units */
  86         unsigned long           base_offset;    /* base address offset */
  87         unsigned int            *cpu_map;       /* unit->cpu map, empty
  88                                                  * entries contain NR_CPUS */
  89 };
  90
  91 struct pcpu_alloc_info {
  92         size_t                  static_size;
  93         size_t                  reserved_size;
  94         size_t                  dyn_size;
  95         size_t                  unit_size;
  96         size_t                  atom_size;
  97         size_t                  alloc_size;
  98         size_t                  __ai_size;      /* internal, don't use */
  99         int                     nr_groups;      /* 0 if grouping unnecessary */
 100         struct pcpu_group_info  groups[];
 101 };
 102
 103 enum pcpu_fc {
 104         PCPU_FC_AUTO,
 105         PCPU_FC_EMBED,
 106         PCPU_FC_PAGE,
 107
 108         PCPU_FC_NR,
 109 };
 110 extern const char *pcpu_fc_names[PCPU_FC_NR];
 111
 112 extern enum pcpu_fc pcpu_chosen_fc;
 113
 114 typedef void * (*pcpu_fc_alloc_fn_t)(unsigned int cpu, size_t size,
 115                                      size_t align);
 116 typedef void (*pcpu_fc_free_fn_t)(void *ptr, size_t size);
 117 typedef void (*pcpu_fc_populate_pte_fn_t)(unsigned long addr);
 118 typedef int (pcpu_fc_cpu_distance_fn_t)(unsigned int from, unsigned int to);
 119
 120 extern struct pcpu_alloc_info * __init pcpu_alloc_alloc_info(int nr_groups,
 121                                                              int nr_units);
 122 extern void __init pcpu_free_alloc_info(struct pcpu_alloc_info *ai);
 123
 124 extern int __init pcpu_setup_first_chunk(const struct pcpu_alloc_info *ai,
 125                                          void *base_addr);
 126
 127 #ifdef CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK
 128 extern int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
 129                                 size_t atom_size,
 130                                 pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
 131                                 pcpu_fc_alloc_fn_t alloc_fn,
 132                                 pcpu_fc_free_fn_t free_fn);
 133 #endif
 134
 135 #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
 136 extern int __init pcpu_page_first_chunk(size_t reserved_size,
 137                                 pcpu_fc_alloc_fn_t alloc_fn,
 138                                 pcpu_fc_free_fn_t free_fn,
 139                                 pcpu_fc_populate_pte_fn_t populate_pte_fn);
 140 #endif
 141
 142 /*
 143  * Use this to get to a cpu's version of the per-cpu object
 144  * dynamically allocated. Non-atomic access to the current CPU's
 145  * version should probably be combined with get_cpu()/put_cpu().
 146  */
 147 #ifdef CONFIG_SMP
 148 #define per_cpu_ptr(ptr, cpu)   SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)))
 149 #else
 150 #define per_cpu_ptr(ptr, cpu)   ({ (void)(cpu); VERIFY_PERCPU_PTR((ptr)); })
 151 #endif
 152
 153 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
 154 extern bool is_kernel_percpu_address(unsigned long addr);
 155
 156 #if !defined(CONFIG_SMP) || !defined(CONFIG_HAVE_SETUP_PER_CPU_AREA)
 157 extern void __init setup_per_cpu_areas(void);
 158 #endif
 159 extern void __init percpu_init_late(void);
 160
 161 extern void __percpu *__alloc_percpu(size_t size, size_t align);
 162 extern void free_percpu(void __percpu *__pdata);
 163 extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
 164
 165 #define alloc_percpu(type)      \
 166         (typeof(type) __percpu *)__alloc_percpu(sizeof(type), __alignof__(type))
 167
 168 /*
 169  * Optional methods for optimized non-lvalue per-cpu variable access.
 170  *
 171  * @var can be a percpu variable or a field of it and its size should
 172  * equal char, int or long.  percpu_read() evaluates to a lvalue and
 173  * all others to void.
 174  *
 175  * These operations are guaranteed to be atomic w.r.t. preemption.
 176  * The generic versions use plain get/put_cpu_var().  Archs are
 177  * encouraged to implement single-instruction alternatives which don't
 178  * require preemption protection.
 179  */
 180 #ifndef percpu_read
 181 # define percpu_read(var)                                               \
 182   ({                                                                    \
 183         typeof(var) *pr_ptr__ = &(var);                                 \
 184         typeof(var) pr_ret__;                                           \
 185         pr_ret__ = get_cpu_var(*pr_ptr__);                              \
 186         put_cpu_var(*pr_ptr__);                                         \
 187         pr_ret__;                                                       \
 188   })
 189 #endif
 190
 191 #define __percpu_generic_to_op(var, val, op)                            \
 192 do {                                                                    \
 193         typeof(var) *pgto_ptr__ = &(var);                               \
 194         get_cpu_var(*pgto_ptr__) op val;                                \
 195         put_cpu_var(*pgto_ptr__);                                       \
 196 } while (0)
 197
 198 #ifndef percpu_write
 199 # define percpu_write(var, val)         __percpu_generic_to_op(var, (val), =)
 200 #endif
 201
 202 #ifndef percpu_add
 203 # define percpu_add(var, val)           __percpu_generic_to_op(var, (val), +=)
 204 #endif
 205
 206 #ifndef percpu_sub
 207 # define percpu_sub(var, val)           __percpu_generic_to_op(var, (val), -=)
 208 #endif
 209
 210 #ifndef percpu_and
 211 # define percpu_and(var, val)           __percpu_generic_to_op(var, (val), &=)
 212 #endif
 213
 214 #ifndef percpu_or
 215 # define percpu_or(var, val)            __percpu_generic_to_op(var, (val), |=)
 216 #endif
 217
 218 #ifndef percpu_xor
 219 # define percpu_xor(var, val)           __percpu_generic_to_op(var, (val), ^=)
 220 #endif
 221
 222 /*
 223  * Branching function to split up a function into a set of functions that
 224  * are called for different scalar sizes of the objects handled.
 225  */
 226
 227 extern void __bad_size_call_parameter(void);
 228
 229 #define __pcpu_size_call_return(stem, variable)                         \
 230 ({      typeof(variable) pscr_ret__;                                    \
 231         __verify_pcpu_ptr(&(variable));                                 \
 232         switch(sizeof(variable)) {                                      \
 233         case 1: pscr_ret__ = stem##1(variable);break;                   \
 234         case 2: pscr_ret__ = stem##2(variable);break;                   \
 235         case 4: pscr_ret__ = stem##4(variable);break;                   \
 236         case 8: pscr_ret__ = stem##8(variable);break;                   \
 237         default:                                                        \
 238                 __bad_size_call_parameter();break;                      \
 239         }                                                               \
 240         pscr_ret__;                                                     \
 241 })
 242
 243 #define __pcpu_size_call_return2(stem, variable, ...)                   \
 244 ({                                                                      \
 245         typeof(variable) pscr2_ret__;                                   \
 246         __verify_pcpu_ptr(&(variable));                                 \
 247         switch(sizeof(variable)) {                                      \
 248         case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break;    \
 249         case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break;    \
 250         case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break;    \
 251         case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break;    \
 252         default:                                                        \
 253                 __bad_size_call_parameter(); break;                     \
 254         }                                                               \
 255         pscr2_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 #define _this_cpu_generic_add_return(pcp, val)                          \
 421 ({                                                                      \
 422         typeof(pcp) ret__;                                              \
 423         preempt_disable();                                              \
 424         __this_cpu_add(pcp, val);                                       \
 425         ret__ = __this_cpu_read(pcp);                                   \
 426         preempt_enable();                                               \
 427         ret__;                                                          \
 428 })
 429
 430 #ifndef this_cpu_add_return
 431 # ifndef this_cpu_add_return_1
 432 #  define this_cpu_add_return_1(pcp, val)       _this_cpu_generic_add_return(pcp, val)
 433 # endif
 434 # ifndef this_cpu_add_return_2
 435 #  define this_cpu_add_return_2(pcp, val)       _this_cpu_generic_add_return(pcp, val)
 436 # endif
 437 # ifndef this_cpu_add_return_4
 438 #  define this_cpu_add_return_4(pcp, val)       _this_cpu_generic_add_return(pcp, val)
 439 # endif
 440 # ifndef this_cpu_add_return_8
 441 #  define this_cpu_add_return_8(pcp, val)       _this_cpu_generic_add_return(pcp, val)
 442 # endif
 443 # define this_cpu_add_return(pcp, val)  __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
 444 #endif
 445
 446 #define this_cpu_sub_return(pcp, val)   this_cpu_add_return(pcp, -(val))
 447 #define this_cpu_inc_return(pcp)        this_cpu_add_return(pcp, 1)
 448 #define this_cpu_dec_return(pcp)        this_cpu_add_return(pcp, -1)
 449
 450 #define _this_cpu_generic_xchg(pcp, nval)                               \
 451 ({      typeof(pcp) ret__;                                              \
 452         preempt_disable();                                              \
 453         ret__ = __this_cpu_read(pcp);                                   \
 454         __this_cpu_write(pcp, nval);                                    \
 455         preempt_enable();                                               \
 456         ret__;                                                          \
 457 })
 458
 459 #ifndef this_cpu_xchg
 460 # ifndef this_cpu_xchg_1
 461 #  define this_cpu_xchg_1(pcp, nval)    _this_cpu_generic_xchg(pcp, nval)
 462 # endif
 463 # ifndef this_cpu_xchg_2
 464 #  define this_cpu_xchg_2(pcp, nval)    _this_cpu_generic_xchg(pcp, nval)
 465 # endif
 466 # ifndef this_cpu_xchg_4
 467 #  define this_cpu_xchg_4(pcp, nval)    _this_cpu_generic_xchg(pcp, nval)
 468 # endif
 469 # ifndef this_cpu_xchg_8
 470 #  define this_cpu_xchg_8(pcp, nval)    _this_cpu_generic_xchg(pcp, nval)
 471 # endif
 472 # define this_cpu_xchg(pcp, nval)       \
 473         __pcpu_size_call_return2(this_cpu_xchg_, (pcp), nval)
 474 #endif
 475
 476 #define _this_cpu_generic_cmpxchg(pcp, oval, nval)                      \
 477 ({      typeof(pcp) ret__;                                              \
 478         preempt_disable();                                              \
 479         ret__ = __this_cpu_read(pcp);                                   \
 480         if (ret__ == (oval))                                            \
 481                 __this_cpu_write(pcp, nval);                            \
 482         preempt_enable();                                               \
 483         ret__;                                                          \
 484 })
 485
 486 #ifndef this_cpu_cmpxchg
 487 # ifndef this_cpu_cmpxchg_1
 488 #  define this_cpu_cmpxchg_1(pcp, oval, nval)   _this_cpu_generic_cmpxchg(pcp, oval, nval)
 489 # endif
 490 # ifndef this_cpu_cmpxchg_2
 491 #  define this_cpu_cmpxchg_2(pcp, oval, nval)   _this_cpu_generic_cmpxchg(pcp, oval, nval)
 492 # endif
 493 # ifndef this_cpu_cmpxchg_4
 494 #  define this_cpu_cmpxchg_4(pcp, oval, nval)   _this_cpu_generic_cmpxchg(pcp, oval, nval)
 495 # endif
 496 # ifndef this_cpu_cmpxchg_8
 497 #  define this_cpu_cmpxchg_8(pcp, oval, nval)   _this_cpu_generic_cmpxchg(pcp, oval, nval)
 498 # endif
 499 # define this_cpu_cmpxchg(pcp, oval, nval)      \
 500         __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
 501 #endif
 502
 503 /*
 504  * Generic percpu operations that do not require preemption handling.
 505  * Either we do not care about races or the caller has the
 506  * responsibility of handling preemptions issues. Arch code can still
 507  * override these instructions since the arch per cpu code may be more
 508  * efficient and may actually get race freeness for free (that is the
 509  * case for x86 for example).
 510  *
 511  * If there is no other protection through preempt disable and/or
 512  * disabling interupts then one of these RMW operations can show unexpected
 513  * behavior because the execution thread was rescheduled on another processor
 514  * or an interrupt occurred and the same percpu variable was modified from
 515  * the interrupt context.
 516  */
 517 #ifndef __this_cpu_read
 518 # ifndef __this_cpu_read_1
 519 #  define __this_cpu_read_1(pcp)        (*__this_cpu_ptr(&(pcp)))
 520 # endif
 521 # ifndef __this_cpu_read_2
 522 #  define __this_cpu_read_2(pcp)        (*__this_cpu_ptr(&(pcp)))
 523 # endif
 524 # ifndef __this_cpu_read_4
 525 #  define __this_cpu_read_4(pcp)        (*__this_cpu_ptr(&(pcp)))
 526 # endif
 527 # ifndef __this_cpu_read_8
 528 #  define __this_cpu_read_8(pcp)        (*__this_cpu_ptr(&(pcp)))
 529 # endif
 530 # define __this_cpu_read(pcp)   __pcpu_size_call_return(__this_cpu_read_, (pcp))
 531 #endif
 532
 533 #define __this_cpu_generic_to_op(pcp, val, op)                          \
 534 do {                                                                    \
 535         *__this_cpu_ptr(&(pcp)) op val;                                 \
 536 } while (0)
 537
 538 #ifndef __this_cpu_write
 539 # ifndef __this_cpu_write_1
 540 #  define __this_cpu_write_1(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 541 # endif
 542 # ifndef __this_cpu_write_2
 543 #  define __this_cpu_write_2(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 544 # endif
 545 # ifndef __this_cpu_write_4
 546 #  define __this_cpu_write_4(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 547 # endif
 548 # ifndef __this_cpu_write_8
 549 #  define __this_cpu_write_8(pcp, val)  __this_cpu_generic_to_op((pcp), (val), =)
 550 # endif
 551 # define __this_cpu_write(pcp, val)     __pcpu_size_call(__this_cpu_write_, (pcp), (val))
 552 #endif
 553
 554 #ifndef __this_cpu_add
 555 # ifndef __this_cpu_add_1
 556 #  define __this_cpu_add_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 557 # endif
 558 # ifndef __this_cpu_add_2
 559 #  define __this_cpu_add_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 560 # endif
 561 # ifndef __this_cpu_add_4
 562 #  define __this_cpu_add_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 563 # endif
 564 # ifndef __this_cpu_add_8
 565 #  define __this_cpu_add_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), +=)
 566 # endif
 567 # define __this_cpu_add(pcp, val)       __pcpu_size_call(__this_cpu_add_, (pcp), (val))
 568 #endif
 569
 570 #ifndef __this_cpu_sub
 571 # define __this_cpu_sub(pcp, val)       __this_cpu_add((pcp), -(val))
 572 #endif
 573
 574 #ifndef __this_cpu_inc
 575 # define __this_cpu_inc(pcp)            __this_cpu_add((pcp), 1)
 576 #endif
 577
 578 #ifndef __this_cpu_dec
 579 # define __this_cpu_dec(pcp)            __this_cpu_sub((pcp), 1)
 580 #endif
 581
 582 #ifndef __this_cpu_and
 583 # ifndef __this_cpu_and_1
 584 #  define __this_cpu_and_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 585 # endif
 586 # ifndef __this_cpu_and_2
 587 #  define __this_cpu_and_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 588 # endif
 589 # ifndef __this_cpu_and_4
 590 #  define __this_cpu_and_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 591 # endif
 592 # ifndef __this_cpu_and_8
 593 #  define __this_cpu_and_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), &=)
 594 # endif
 595 # define __this_cpu_and(pcp, val)       __pcpu_size_call(__this_cpu_and_, (pcp), (val))
 596 #endif
 597
 598 #ifndef __this_cpu_or
 599 # ifndef __this_cpu_or_1
 600 #  define __this_cpu_or_1(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 601 # endif
 602 # ifndef __this_cpu_or_2
 603 #  define __this_cpu_or_2(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 604 # endif
 605 # ifndef __this_cpu_or_4
 606 #  define __this_cpu_or_4(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 607 # endif
 608 # ifndef __this_cpu_or_8
 609 #  define __this_cpu_or_8(pcp, val)     __this_cpu_generic_to_op((pcp), (val), |=)
 610 # endif
 611 # define __this_cpu_or(pcp, val)        __pcpu_size_call(__this_cpu_or_, (pcp), (val))
 612 #endif
 613
 614 #ifndef __this_cpu_xor
 615 # ifndef __this_cpu_xor_1
 616 #  define __this_cpu_xor_1(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 617 # endif
 618 # ifndef __this_cpu_xor_2
 619 #  define __this_cpu_xor_2(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 620 # endif
 621 # ifndef __this_cpu_xor_4
 622 #  define __this_cpu_xor_4(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 623 # endif
 624 # ifndef __this_cpu_xor_8
 625 #  define __this_cpu_xor_8(pcp, val)    __this_cpu_generic_to_op((pcp), (val), ^=)
 626 # endif
 627 # define __this_cpu_xor(pcp, val)       __pcpu_size_call(__this_cpu_xor_, (pcp), (val))
 628 #endif
 629
 630 #define __this_cpu_generic_add_return(pcp, val)                         \
 631 ({                                                                      \
 632         __this_cpu_add(pcp, val);                                       \
 633         __this_cpu_read(pcp);                                           \
 634 })
 635
 636 #ifndef __this_cpu_add_return
 637 # ifndef __this_cpu_add_return_1
 638 #  define __this_cpu_add_return_1(pcp, val)     __this_cpu_generic_add_return(pcp, val)
 639 # endif
 640 # ifndef __this_cpu_add_return_2
 641 #  define __this_cpu_add_return_2(pcp, val)     __this_cpu_generic_add_return(pcp, val)
 642 # endif
 643 # ifndef __this_cpu_add_return_4
 644 #  define __this_cpu_add_return_4(pcp, val)     __this_cpu_generic_add_return(pcp, val)
 645 # endif
 646 # ifndef __this_cpu_add_return_8
 647 #  define __this_cpu_add_return_8(pcp, val)     __this_cpu_generic_add_return(pcp, val)
 648 # endif
 649 # define __this_cpu_add_return(pcp, val)        __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
 650 #endif
 651
 652 #define __this_cpu_sub_return(pcp, val) this_cpu_add_return(pcp, -(val))
 653 #define __this_cpu_inc_return(pcp)      this_cpu_add_return(pcp, 1)
 654 #define __this_cpu_dec_return(pcp)      this_cpu_add_return(pcp, -1)
 655
 656 #define __this_cpu_generic_xchg(pcp, nval)                              \
 657 ({      typeof(pcp) ret__;                                              \
 658         ret__ = __this_cpu_read(pcp);                                   \
 659         __this_cpu_write(pcp, nval);                                    \
 660         ret__;                                                          \
 661 })
 662
 663 #ifndef __this_cpu_xchg
 664 # ifndef __this_cpu_xchg_1
 665 #  define __this_cpu_xchg_1(pcp, nval)  __this_cpu_generic_xchg(pcp, nval)
 666 # endif
 667 # ifndef __this_cpu_xchg_2
 668 #  define __this_cpu_xchg_2(pcp, nval)  __this_cpu_generic_xchg(pcp, nval)
 669 # endif
 670 # ifndef __this_cpu_xchg_4
 671 #  define __this_cpu_xchg_4(pcp, nval)  __this_cpu_generic_xchg(pcp, nval)
 672 # endif
 673 # ifndef __this_cpu_xchg_8
 674 #  define __this_cpu_xchg_8(pcp, nval)  __this_cpu_generic_xchg(pcp, nval)
 675 # endif
 676 # define __this_cpu_xchg(pcp, nval)     \
 677         __pcpu_size_call_return2(__this_cpu_xchg_, (pcp), nval)
 678 #endif
 679
 680 #define __this_cpu_generic_cmpxchg(pcp, oval, nval)                     \
 681 ({                                                                      \
 682         typeof(pcp) ret__;                                              \
 683         ret__ = __this_cpu_read(pcp);                                   \
 684         if (ret__ == (oval))                                            \
 685                 __this_cpu_write(pcp, nval);                            \
 686         ret__;                                                          \
 687 })
 688
 689 #ifndef __this_cpu_cmpxchg
 690 # ifndef __this_cpu_cmpxchg_1
 691 #  define __this_cpu_cmpxchg_1(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
 692 # endif
 693 # ifndef __this_cpu_cmpxchg_2
 694 #  define __this_cpu_cmpxchg_2(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
 695 # endif
 696 # ifndef __this_cpu_cmpxchg_4
 697 #  define __this_cpu_cmpxchg_4(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
 698 # endif
 699 # ifndef __this_cpu_cmpxchg_8
 700 #  define __this_cpu_cmpxchg_8(pcp, oval, nval) __this_cpu_generic_cmpxchg(pcp, oval, nval)
 701 # endif
 702 # define __this_cpu_cmpxchg(pcp, oval, nval)    \
 703         __pcpu_size_call_return2(__this_cpu_cmpxchg_, pcp, oval, nval)
 704 #endif
 705
 706 /*
 707  * IRQ safe versions of the per cpu RMW operations. Note that these operations
 708  * are *not* safe against modification of the same variable from another
 709  * processors (which one gets when using regular atomic operations)
 710  * They are guaranteed to be atomic vs. local interrupts and
 711  * preemption only.
 712  */
 713 #define irqsafe_cpu_generic_to_op(pcp, val, op)                         \
 714 do {                                                                    \
 715         unsigned long flags;                                            \
 716         local_irq_save(flags);                                          \
 717         *__this_cpu_ptr(&(pcp)) op val;                                 \
 718         local_irq_restore(flags);                                       \
 719 } while (0)
 720
 721 #ifndef irqsafe_cpu_add
 722 # ifndef irqsafe_cpu_add_1
 723 #  define irqsafe_cpu_add_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 724 # endif
 725 # ifndef irqsafe_cpu_add_2
 726 #  define irqsafe_cpu_add_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 727 # endif
 728 # ifndef irqsafe_cpu_add_4
 729 #  define irqsafe_cpu_add_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 730 # endif
 731 # ifndef irqsafe_cpu_add_8
 732 #  define irqsafe_cpu_add_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), +=)
 733 # endif
 734 # define irqsafe_cpu_add(pcp, val) __pcpu_size_call(irqsafe_cpu_add_, (pcp), (val))
 735 #endif
 736
 737 #ifndef irqsafe_cpu_sub
 738 # define irqsafe_cpu_sub(pcp, val)      irqsafe_cpu_add((pcp), -(val))
 739 #endif
 740
 741 #ifndef irqsafe_cpu_inc
 742 # define irqsafe_cpu_inc(pcp)   irqsafe_cpu_add((pcp), 1)
 743 #endif
 744
 745 #ifndef irqsafe_cpu_dec
 746 # define irqsafe_cpu_dec(pcp)   irqsafe_cpu_sub((pcp), 1)
 747 #endif
 748
 749 #ifndef irqsafe_cpu_and
 750 # ifndef irqsafe_cpu_and_1
 751 #  define irqsafe_cpu_and_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 752 # endif
 753 # ifndef irqsafe_cpu_and_2
 754 #  define irqsafe_cpu_and_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 755 # endif
 756 # ifndef irqsafe_cpu_and_4
 757 #  define irqsafe_cpu_and_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 758 # endif
 759 # ifndef irqsafe_cpu_and_8
 760 #  define irqsafe_cpu_and_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), &=)
 761 # endif
 762 # define irqsafe_cpu_and(pcp, val) __pcpu_size_call(irqsafe_cpu_and_, (val))
 763 #endif
 764
 765 #ifndef irqsafe_cpu_or
 766 # ifndef irqsafe_cpu_or_1
 767 #  define irqsafe_cpu_or_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 768 # endif
 769 # ifndef irqsafe_cpu_or_2
 770 #  define irqsafe_cpu_or_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 771 # endif
 772 # ifndef irqsafe_cpu_or_4
 773 #  define irqsafe_cpu_or_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 774 # endif
 775 # ifndef irqsafe_cpu_or_8
 776 #  define irqsafe_cpu_or_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), |=)
 777 # endif
 778 # define irqsafe_cpu_or(pcp, val) __pcpu_size_call(irqsafe_cpu_or_, (val))
 779 #endif
 780
 781 #ifndef irqsafe_cpu_xor
 782 # ifndef irqsafe_cpu_xor_1
 783 #  define irqsafe_cpu_xor_1(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 784 # endif
 785 # ifndef irqsafe_cpu_xor_2
 786 #  define irqsafe_cpu_xor_2(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 787 # endif
 788 # ifndef irqsafe_cpu_xor_4
 789 #  define irqsafe_cpu_xor_4(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 790 # endif
 791 # ifndef irqsafe_cpu_xor_8
 792 #  define irqsafe_cpu_xor_8(pcp, val) irqsafe_cpu_generic_to_op((pcp), (val), ^=)
 793 # endif
 794 # define irqsafe_cpu_xor(pcp, val) __pcpu_size_call(irqsafe_cpu_xor_, (val))
 795 #endif
 796
 797 #define irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)                    \
 798 ({                                                                      \
 799         typeof(pcp) ret__;                                              \
 800         unsigned long flags;                                            \
 801         local_irq_save(flags);                                          \
 802         ret__ = __this_cpu_read(pcp);                                   \
 803         if (ret__ == (oval))                                            \
 804                 __this_cpu_write(pcp, nval);                            \
 805         local_irq_restore(flags);                                       \
 806         ret__;                                                          \
 807 })
 808
 809 #ifndef irqsafe_cpu_cmpxchg
 810 # ifndef irqsafe_cpu_cmpxchg_1
 811 #  define irqsafe_cpu_cmpxchg_1(pcp, oval, nval)        irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
 812 # endif
 813 # ifndef irqsafe_cpu_cmpxchg_2
 814 #  define irqsafe_cpu_cmpxchg_2(pcp, oval, nval)        irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
 815 # endif
 816 # ifndef irqsafe_cpu_cmpxchg_4
 817 #  define irqsafe_cpu_cmpxchg_4(pcp, oval, nval)        irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
 818 # endif
 819 # ifndef irqsafe_cpu_cmpxchg_8
 820 #  define irqsafe_cpu_cmpxchg_8(pcp, oval, nval)        irqsafe_cpu_generic_cmpxchg(pcp, oval, nval)
 821 # endif
 822 # define irqsafe_cpu_cmpxchg(pcp, oval, nval)           \
 823         __pcpu_size_call_return2(irqsafe_cpu_cmpxchg_, (pcp), oval, nval)
 824 #endif
 825
 826 #endif /* __LINUX_PERCPU_H */