include/linux/percpu-defs.h

   1 /*
   2  * linux/percpu-defs.h - basic definitions for percpu areas
   3  *
   4  * DO NOT INCLUDE DIRECTLY OUTSIDE PERCPU IMPLEMENTATION PROPER.
   5  *
   6  * This file is separate from linux/percpu.h to avoid cyclic inclusion
   7  * dependency from arch header files.  Only to be included from
   8  * asm/percpu.h.
   9  *
  10  * This file includes macros necessary to declare percpu sections and
  11  * variables, and definitions of percpu accessors and operations.  It
  12  * should provide enough percpu features to arch header files even when
  13  * they can only include asm/percpu.h to avoid cyclic inclusion dependency.
  14  */
  15
  16 #ifndef _LINUX_PERCPU_DEFS_H
  17 #define _LINUX_PERCPU_DEFS_H
  18
  19 #ifdef CONFIG_SMP
  20
  21 #ifdef MODULE
  22 #define PER_CPU_SHARED_ALIGNED_SECTION ""
  23 #define PER_CPU_ALIGNED_SECTION ""
  24 #else
  25 #define PER_CPU_SHARED_ALIGNED_SECTION "..shared_aligned"
  26 #define PER_CPU_ALIGNED_SECTION "..shared_aligned"
  27 #endif
  28 #define PER_CPU_FIRST_SECTION "..first"
  29
  30 #else
  31
  32 #define PER_CPU_SHARED_ALIGNED_SECTION ""
  33 #define PER_CPU_ALIGNED_SECTION "..shared_aligned"
  34 #define PER_CPU_FIRST_SECTION ""
  35
  36 #endif
  37
  38 #ifdef CONFIG_PAGE_TABLE_ISOLATION
  39 #define USER_MAPPED_SECTION "..user_mapped"
  40 #else
  41 #define USER_MAPPED_SECTION ""
  42 #endif
  43
  44 /*
  45  * Base implementations of per-CPU variable declarations and definitions, where
  46  * the section in which the variable is to be placed is provided by the
  47  * 'sec' argument.  This may be used to affect the parameters governing the
  48  * variable's storage.
  49  *
  50  * NOTE!  The sections for the DECLARE and for the DEFINE must match, lest
  51  * linkage errors occur due the compiler generating the wrong code to access
  52  * that section.
  53  */
  54 #define __PCPU_ATTRS(sec)                                               \
  55         __percpu __attribute__((section(PER_CPU_BASE_SECTION sec)))     \
  56         PER_CPU_ATTRIBUTES
  57
  58 #define __PCPU_DUMMY_ATTRS                                              \
  59         __attribute__((section(".discard"), unused))
  60
  61 /*
  62  * s390 and alpha modules require percpu variables to be defined as
  63  * weak to force the compiler to generate GOT based external
  64  * references for them.  This is necessary because percpu sections
  65  * will be located outside of the usually addressable area.
  66  *
  67  * This definition puts the following two extra restrictions when
  68  * defining percpu variables.
  69  *
  70  * 1. The symbol must be globally unique, even the static ones.
  71  * 2. Static percpu variables cannot be defined inside a function.
  72  *
  73  * Archs which need weak percpu definitions should define
  74  * ARCH_NEEDS_WEAK_PER_CPU in asm/percpu.h when necessary.
  75  *
  76  * To ensure that the generic code observes the above two
  77  * restrictions, if CONFIG_DEBUG_FORCE_WEAK_PER_CPU is set weak
  78  * definition is used for all cases.
  79  */
  80 #if defined(ARCH_NEEDS_WEAK_PER_CPU) || defined(CONFIG_DEBUG_FORCE_WEAK_PER_CPU)
  81 /*
  82  * __pcpu_scope_* dummy variable is used to enforce scope.  It
  83  * receives the static modifier when it's used in front of
  84  * DEFINE_PER_CPU() and will trigger build failure if
  85  * DECLARE_PER_CPU() is used for the same variable.
  86  *
  87  * __pcpu_unique_* dummy variable is used to enforce symbol uniqueness
  88  * such that hidden weak symbol collision, which will cause unrelated
  89  * variables to share the same address, can be detected during build.
  90  */
  91 #define DECLARE_PER_CPU_SECTION(type, name, sec)                        \
  92         extern __PCPU_DUMMY_ATTRS char __pcpu_scope_##name;             \
  93         extern __PCPU_ATTRS(sec) __typeof__(type) name
  94
  95 #define DEFINE_PER_CPU_SECTION(type, name, sec)                         \
  96         __PCPU_DUMMY_ATTRS char __pcpu_scope_##name;                    \
  97         extern __PCPU_DUMMY_ATTRS char __pcpu_unique_##name;            \
  98         __PCPU_DUMMY_ATTRS char __pcpu_unique_##name;                   \
  99         extern __PCPU_ATTRS(sec) __typeof__(type) name;                 \
 100         __PCPU_ATTRS(sec) PER_CPU_DEF_ATTRIBUTES __weak                 \
 101         __typeof__(type) name
 102 #else
 103 /*
 104  * Normal declaration and definition macros.
 105  */
 106 #define DECLARE_PER_CPU_SECTION(type, name, sec)                        \
 107         extern __PCPU_ATTRS(sec) __typeof__(type) name
 108
 109 #define DEFINE_PER_CPU_SECTION(type, name, sec)                         \
 110         __PCPU_ATTRS(sec) PER_CPU_DEF_ATTRIBUTES                        \
 111         __typeof__(type) name
 112 #endif
 113
 114 /*
 115  * Variant on the per-CPU variable declaration/definition theme used for
 116  * ordinary per-CPU variables.
 117  */
 118 #define DECLARE_PER_CPU(type, name)                                     \
 119         DECLARE_PER_CPU_SECTION(type, name, "")
 120
 121 #define DEFINE_PER_CPU(type, name)                                      \
 122         DEFINE_PER_CPU_SECTION(type, name, "")
 123
 124 #define DECLARE_PER_CPU_USER_MAPPED(type, name)                         \
 125         DECLARE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION)
 126
 127 #define DEFINE_PER_CPU_USER_MAPPED(type, name)                          \
 128         DEFINE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION)
 129
 130 /*
 131  * Declaration/definition used for per-CPU variables that must come first in
 132  * the set of variables.
 133  */
 134 #define DECLARE_PER_CPU_FIRST(type, name)                               \
 135         DECLARE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION)
 136
 137 #define DEFINE_PER_CPU_FIRST(type, name)                                \
 138         DEFINE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION)
 139
 140 /*
 141  * Declaration/definition used for per-CPU variables that must be cacheline
 142  * aligned under SMP conditions so that, whilst a particular instance of the
 143  * data corresponds to a particular CPU, inefficiencies due to direct access by
 144  * other CPUs are reduced by preventing the data from unnecessarily spanning
 145  * cachelines.
 146  *
 147  * An example of this would be statistical data, where each CPU's set of data
 148  * is updated by that CPU alone, but the data from across all CPUs is collated
 149  * by a CPU processing a read from a proc file.
 150  */
 151 #define DECLARE_PER_CPU_SHARED_ALIGNED(type, name)                      \
 152         DECLARE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
 153         ____cacheline_aligned_in_smp
 154
 155 #define DEFINE_PER_CPU_SHARED_ALIGNED(type, name)                       \
 156         DEFINE_PER_CPU_SECTION(type, name, PER_CPU_SHARED_ALIGNED_SECTION) \
 157         ____cacheline_aligned_in_smp
 158
 159 #define DECLARE_PER_CPU_SHARED_ALIGNED_USER_MAPPED(type, name)          \
 160         DECLARE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION PER_CPU_SHARED_ALIGNED_SECTION) \
 161         ____cacheline_aligned_in_smp
 162
 163 #define DEFINE_PER_CPU_SHARED_ALIGNED_USER_MAPPED(type, name)           \
 164         DEFINE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION PER_CPU_SHARED_ALIGNED_SECTION) \
 165         ____cacheline_aligned_in_smp
 166
 167 #define DECLARE_PER_CPU_ALIGNED(type, name)                             \
 168         DECLARE_PER_CPU_SECTION(type, name, PER_CPU_ALIGNED_SECTION)    \
 169         ____cacheline_aligned
 170
 171 #define DEFINE_PER_CPU_ALIGNED(type, name)                              \
 172         DEFINE_PER_CPU_SECTION(type, name, PER_CPU_ALIGNED_SECTION)     \
 173         ____cacheline_aligned
 174
 175 /*
 176  * Declaration/definition used for per-CPU variables that must be page aligned.
 177  */
 178 #define DECLARE_PER_CPU_PAGE_ALIGNED(type, name)                        \
 179         DECLARE_PER_CPU_SECTION(type, name, "..page_aligned")           \
 180         __aligned(PAGE_SIZE)
 181
 182 #define DEFINE_PER_CPU_PAGE_ALIGNED(type, name)                         \
 183         DEFINE_PER_CPU_SECTION(type, name, "..page_aligned")            \
 184         __aligned(PAGE_SIZE)
 185 /*
 186  * Declaration/definition used for per-CPU variables that must be page aligned and need to be mapped in user mode.
 187  */
 188 #define DECLARE_PER_CPU_PAGE_ALIGNED_USER_MAPPED(type, name)            \
 189         DECLARE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION"..page_aligned") \
 190         __aligned(PAGE_SIZE)
 191
 192 #define DEFINE_PER_CPU_PAGE_ALIGNED_USER_MAPPED(type, name)             \
 193         DEFINE_PER_CPU_SECTION(type, name, USER_MAPPED_SECTION"..page_aligned") \
 194         __aligned(PAGE_SIZE)
 195
 196 /*
 197  * Declaration/definition used for per-CPU variables that must be read mostly.
 198  */
 199 #define DECLARE_PER_CPU_READ_MOSTLY(type, name)                         \
 200         DECLARE_PER_CPU_SECTION(type, name, "..read_mostly")
 201
 202 #define DEFINE_PER_CPU_READ_MOSTLY(type, name)                          \
 203         DEFINE_PER_CPU_SECTION(type, name, "..read_mostly")
 204
 205 /*
 206  * Intermodule exports for per-CPU variables.  sparse forgets about
 207  * address space across EXPORT_SYMBOL(), change EXPORT_SYMBOL() to
 208  * noop if __CHECKER__.
 209  */
 210 #ifndef __CHECKER__
 211 #define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(var)
 212 #define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(var)
 213 #else
 214 #define EXPORT_PER_CPU_SYMBOL(var)
 215 #define EXPORT_PER_CPU_SYMBOL_GPL(var)
 216 #endif
 217
 218 /*
 219  * Accessors and operations.
 220  */
 221 #ifndef __ASSEMBLY__
 222
 223 /*
 224  * __verify_pcpu_ptr() verifies @ptr is a percpu pointer without evaluating
 225  * @ptr and is invoked once before a percpu area is accessed by all
 226  * accessors and operations.  This is performed in the generic part of
 227  * percpu and arch overrides don't need to worry about it; however, if an
 228  * arch wants to implement an arch-specific percpu accessor or operation,
 229  * it may use __verify_pcpu_ptr() to verify the parameters.
 230  *
 231  * + 0 is required in order to convert the pointer type from a
 232  * potential array type to a pointer to a single item of the array.
 233  */
 234 #define __verify_pcpu_ptr(ptr)                                          \
 235 do {                                                                    \
 236         const void __percpu *__vpp_verify = (typeof((ptr) + 0))NULL;    \
 237         (void)__vpp_verify;                                             \
 238 } while (0)
 239
 240 #ifdef CONFIG_SMP
 241
 242 /*
 243  * Add an offset to a pointer but keep the pointer as-is.  Use RELOC_HIDE()
 244  * to prevent the compiler from making incorrect assumptions about the
 245  * pointer value.  The weird cast keeps both GCC and sparse happy.
 246  */
 247 #define SHIFT_PERCPU_PTR(__p, __offset)                                 \
 248         RELOC_HIDE((typeof(*(__p)) __kernel __force *)(__p), (__offset))
 249
 250 #define per_cpu_ptr(ptr, cpu)                                           \
 251 ({                                                                      \
 252         __verify_pcpu_ptr(ptr);                                         \
 253         SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu)));                 \
 254 })
 255
 256 #define raw_cpu_ptr(ptr)                                                \
 257 ({                                                                      \
 258         __verify_pcpu_ptr(ptr);                                         \
 259         arch_raw_cpu_ptr(ptr);                                          \
 260 })
 261
 262 #ifdef CONFIG_DEBUG_PREEMPT
 263 #define this_cpu_ptr(ptr)                                               \
 264 ({                                                                      \
 265         __verify_pcpu_ptr(ptr);                                         \
 266         SHIFT_PERCPU_PTR(ptr, my_cpu_offset);                           \
 267 })
 268 #else
 269 #define this_cpu_ptr(ptr) raw_cpu_ptr(ptr)
 270 #endif
 271
 272 #else   /* CONFIG_SMP */
 273
 274 #define VERIFY_PERCPU_PTR(__p)                                          \
 275 ({                                                                      \
 276         __verify_pcpu_ptr(__p);                                         \
 277         (typeof(*(__p)) __kernel __force *)(__p);                       \
 278 })
 279
 280 #define per_cpu_ptr(ptr, cpu)   ({ (void)(cpu); VERIFY_PERCPU_PTR(ptr); })
 281 #define raw_cpu_ptr(ptr)        per_cpu_ptr(ptr, 0)
 282 #define this_cpu_ptr(ptr)       raw_cpu_ptr(ptr)
 283
 284 #endif  /* CONFIG_SMP */
 285
 286 #define per_cpu(var, cpu)       (*per_cpu_ptr(&(var), cpu))
 287
 288 /*
 289  * Must be an lvalue. Since @var must be a simple identifier,
 290  * we force a syntax error here if it isn't.
 291  */
 292 #define get_cpu_var(var)                                                \
 293 (*({                                                                    \
 294         preempt_disable();                                              \
 295         this_cpu_ptr(&var);                                             \
 296 }))
 297
 298 /*
 299  * The weird & is necessary because sparse considers (void)(var) to be
 300  * a direct dereference of percpu variable (var).
 301  */
 302 #define put_cpu_var(var)                                                \
 303 do {                                                                    \
 304         (void)&(var);                                                   \
 305         preempt_enable();                                               \
 306 } while (0)
 307
 308 #define get_cpu_ptr(var)                                                \
 309 ({                                                                      \
 310         preempt_disable();                                              \
 311         this_cpu_ptr(var);                                              \
 312 })
 313
 314 #define put_cpu_ptr(var)                                                \
 315 do {                                                                    \
 316         (void)(var);                                                    \
 317         preempt_enable();                                               \
 318 } while (0)
 319
 320 /*
 321  * Branching function to split up a function into a set of functions that
 322  * are called for different scalar sizes of the objects handled.
 323  */
 324
 325 extern void __bad_size_call_parameter(void);
 326
 327 #ifdef CONFIG_DEBUG_PREEMPT
 328 extern void __this_cpu_preempt_check(const char *op);
 329 #else
 330 static inline void __this_cpu_preempt_check(const char *op) { }
 331 #endif
 332
 333 #define __pcpu_size_call_return(stem, variable)                         \
 334 ({                                                                      \
 335         typeof(variable) pscr_ret__;                                    \
 336         __verify_pcpu_ptr(&(variable));                                 \
 337         switch(sizeof(variable)) {                                      \
 338         case 1: pscr_ret__ = stem##1(variable); break;                  \
 339         case 2: pscr_ret__ = stem##2(variable); break;                  \
 340         case 4: pscr_ret__ = stem##4(variable); break;                  \
 341         case 8: pscr_ret__ = stem##8(variable); break;                  \
 342         default:                                                        \
 343                 __bad_size_call_parameter(); break;                     \
 344         }                                                               \
 345         pscr_ret__;                                                     \
 346 })
 347
 348 #define __pcpu_size_call_return2(stem, variable, ...)                   \
 349 ({                                                                      \
 350         typeof(variable) pscr2_ret__;                                   \
 351         __verify_pcpu_ptr(&(variable));                                 \
 352         switch(sizeof(variable)) {                                      \
 353         case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break;    \
 354         case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break;    \
 355         case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break;    \
 356         case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break;    \
 357         default:                                                        \
 358                 __bad_size_call_parameter(); break;                     \
 359         }                                                               \
 360         pscr2_ret__;                                                    \
 361 })
 362
 363 /*
 364  * Special handling for cmpxchg_double.  cmpxchg_double is passed two
 365  * percpu variables.  The first has to be aligned to a double word
 366  * boundary and the second has to follow directly thereafter.
 367  * We enforce this on all architectures even if they don't support
 368  * a double cmpxchg instruction, since it's a cheap requirement, and it
 369  * avoids breaking the requirement for architectures with the instruction.
 370  */
 371 #define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...)           \
 372 ({                                                                      \
 373         bool pdcrb_ret__;                                               \
 374         __verify_pcpu_ptr(&(pcp1));                                     \
 375         BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2));                     \
 376         VM_BUG_ON((unsigned long)(&(pcp1)) % (2 * sizeof(pcp1)));       \
 377         VM_BUG_ON((unsigned long)(&(pcp2)) !=                           \
 378                   (unsigned long)(&(pcp1)) + sizeof(pcp1));             \
 379         switch(sizeof(pcp1)) {                                          \
 380         case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break;  \
 381         case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break;  \
 382         case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break;  \
 383         case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break;  \
 384         default:                                                        \
 385                 __bad_size_call_parameter(); break;                     \
 386         }                                                               \
 387         pdcrb_ret__;                                                    \
 388 })
 389
 390 #define __pcpu_size_call(stem, variable, ...)                           \
 391 do {                                                                    \
 392         __verify_pcpu_ptr(&(variable));                                 \
 393         switch(sizeof(variable)) {                                      \
 394                 case 1: stem##1(variable, __VA_ARGS__);break;           \
 395                 case 2: stem##2(variable, __VA_ARGS__);break;           \
 396                 case 4: stem##4(variable, __VA_ARGS__);break;           \
 397                 case 8: stem##8(variable, __VA_ARGS__);break;           \
 398                 default:                                                \
 399                         __bad_size_call_parameter();break;              \
 400         }                                                               \
 401 } while (0)
 402
 403 /*
 404  * this_cpu operations (C) 2008-2013 Christoph Lameter <cl@linux.com>
 405  *
 406  * Optimized manipulation for memory allocated through the per cpu
 407  * allocator or for addresses of per cpu variables.
 408  *
 409  * These operation guarantee exclusivity of access for other operations
 410  * on the *same* processor. The assumption is that per cpu data is only
 411  * accessed by a single processor instance (the current one).
 412  *
 413  * The arch code can provide optimized implementation by defining macros
 414  * for certain scalar sizes. F.e. provide this_cpu_add_2() to provide per
 415  * cpu atomic operations for 2 byte sized RMW actions. If arch code does
 416  * not provide operations for a scalar size then the fallback in the
 417  * generic code will be used.
 418  *
 419  * cmpxchg_double replaces two adjacent scalars at once.  The first two
 420  * parameters are per cpu variables which have to be of the same size.  A
 421  * truth value is returned to indicate success or failure (since a double
 422  * register result is difficult to handle).  There is very limited hardware
 423  * support for these operations, so only certain sizes may work.
 424  */
 425
 426 /*
 427  * Operations for contexts where we do not want to do any checks for
 428  * preemptions.  Unless strictly necessary, always use [__]this_cpu_*()
 429  * instead.
 430  *
 431  * If there is no other protection through preempt disable and/or disabling
 432  * interupts then one of these RMW operations can show unexpected behavior
 433  * because the execution thread was rescheduled on another processor or an
 434  * interrupt occurred and the same percpu variable was modified from the
 435  * interrupt context.
 436  */
 437 #define raw_cpu_read(pcp)               __pcpu_size_call_return(raw_cpu_read_, pcp)
 438 #define raw_cpu_write(pcp, val)         __pcpu_size_call(raw_cpu_write_, pcp, val)
 439 #define raw_cpu_add(pcp, val)           __pcpu_size_call(raw_cpu_add_, pcp, val)
 440 #define raw_cpu_and(pcp, val)           __pcpu_size_call(raw_cpu_and_, pcp, val)
 441 #define raw_cpu_or(pcp, val)            __pcpu_size_call(raw_cpu_or_, pcp, val)
 442 #define raw_cpu_add_return(pcp, val)    __pcpu_size_call_return2(raw_cpu_add_return_, pcp, val)
 443 #define raw_cpu_xchg(pcp, nval)         __pcpu_size_call_return2(raw_cpu_xchg_, pcp, nval)
 444 #define raw_cpu_cmpxchg(pcp, oval, nval) \
 445         __pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval)
 446 #define raw_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
 447         __pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, pcp1, pcp2, oval1, oval2, nval1, nval2)
 448
 449 #define raw_cpu_sub(pcp, val)           raw_cpu_add(pcp, -(val))
 450 #define raw_cpu_inc(pcp)                raw_cpu_add(pcp, 1)
 451 #define raw_cpu_dec(pcp)                raw_cpu_sub(pcp, 1)
 452 #define raw_cpu_sub_return(pcp, val)    raw_cpu_add_return(pcp, -(typeof(pcp))(val))
 453 #define raw_cpu_inc_return(pcp)         raw_cpu_add_return(pcp, 1)
 454 #define raw_cpu_dec_return(pcp)         raw_cpu_add_return(pcp, -1)
 455
 456 /*
 457  * Operations for contexts that are safe from preemption/interrupts.  These
 458  * operations verify that preemption is disabled.
 459  */
 460 #define __this_cpu_read(pcp)                                            \
 461 ({                                                                      \
 462         __this_cpu_preempt_check("read");                               \
 463         raw_cpu_read(pcp);                                              \
 464 })
 465
 466 #define __this_cpu_write(pcp, val)                                      \
 467 ({                                                                      \
 468         __this_cpu_preempt_check("write");                              \
 469         raw_cpu_write(pcp, val);                                        \
 470 })
 471
 472 #define __this_cpu_add(pcp, val)                                        \
 473 ({                                                                      \
 474         __this_cpu_preempt_check("add");                                \
 475         raw_cpu_add(pcp, val);                                          \
 476 })
 477
 478 #define __this_cpu_and(pcp, val)                                        \
 479 ({                                                                      \
 480         __this_cpu_preempt_check("and");                                \
 481         raw_cpu_and(pcp, val);                                          \
 482 })
 483
 484 #define __this_cpu_or(pcp, val)                                         \
 485 ({                                                                      \
 486         __this_cpu_preempt_check("or");                                 \
 487         raw_cpu_or(pcp, val);                                           \
 488 })
 489
 490 #define __this_cpu_add_return(pcp, val)                                 \
 491 ({                                                                      \
 492         __this_cpu_preempt_check("add_return");                         \
 493         raw_cpu_add_return(pcp, val);                                   \
 494 })
 495
 496 #define __this_cpu_xchg(pcp, nval)                                      \
 497 ({                                                                      \
 498         __this_cpu_preempt_check("xchg");                               \
 499         raw_cpu_xchg(pcp, nval);                                        \
 500 })
 501
 502 #define __this_cpu_cmpxchg(pcp, oval, nval)                             \
 503 ({                                                                      \
 504         __this_cpu_preempt_check("cmpxchg");                            \
 505         raw_cpu_cmpxchg(pcp, oval, nval);                               \
 506 })
 507
 508 #define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
 509 ({      __this_cpu_preempt_check("cmpxchg_double");                     \
 510         raw_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2); \
 511 })
 512
 513 #define __this_cpu_sub(pcp, val)        __this_cpu_add(pcp, -(typeof(pcp))(val))
 514 #define __this_cpu_inc(pcp)             __this_cpu_add(pcp, 1)
 515 #define __this_cpu_dec(pcp)             __this_cpu_sub(pcp, 1)
 516 #define __this_cpu_sub_return(pcp, val) __this_cpu_add_return(pcp, -(typeof(pcp))(val))
 517 #define __this_cpu_inc_return(pcp)      __this_cpu_add_return(pcp, 1)
 518 #define __this_cpu_dec_return(pcp)      __this_cpu_add_return(pcp, -1)
 519
 520 /*
 521  * Operations with implied preemption/interrupt protection.  These
 522  * operations can be used without worrying about preemption or interrupt.
 523  */
 524 #define this_cpu_read(pcp)              __pcpu_size_call_return(this_cpu_read_, pcp)
 525 #define this_cpu_write(pcp, val)        __pcpu_size_call(this_cpu_write_, pcp, val)
 526 #define this_cpu_add(pcp, val)          __pcpu_size_call(this_cpu_add_, pcp, val)
 527 #define this_cpu_and(pcp, val)          __pcpu_size_call(this_cpu_and_, pcp, val)
 528 #define this_cpu_or(pcp, val)           __pcpu_size_call(this_cpu_or_, pcp, val)
 529 #define this_cpu_add_return(pcp, val)   __pcpu_size_call_return2(this_cpu_add_return_, pcp, val)
 530 #define this_cpu_xchg(pcp, nval)        __pcpu_size_call_return2(this_cpu_xchg_, pcp, nval)
 531 #define this_cpu_cmpxchg(pcp, oval, nval) \
 532         __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval)
 533 #define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \
 534         __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, pcp1, pcp2, oval1, oval2, nval1, nval2)
 535
 536 #define this_cpu_sub(pcp, val)          this_cpu_add(pcp, -(typeof(pcp))(val))
 537 #define this_cpu_inc(pcp)               this_cpu_add(pcp, 1)
 538 #define this_cpu_dec(pcp)               this_cpu_sub(pcp, 1)
 539 #define this_cpu_sub_return(pcp, val)   this_cpu_add_return(pcp, -(typeof(pcp))(val))
 540 #define this_cpu_inc_return(pcp)        this_cpu_add_return(pcp, 1)
 541 #define this_cpu_dec_return(pcp)        this_cpu_add_return(pcp, -1)
 542
 543 #endif /* __ASSEMBLY__ */
 544 #endif /* _LINUX_PERCPU_DEFS_H */