LXR linux/include/asm-generic/percpu.h

   1#ifndef _ASM_GENERIC_PERCPU_H_
   2#define _ASM_GENERIC_PERCPU_H_
   3#include <linux/compiler.h>
   4#include <linux/threads.h>
   5
   6#define __GENERIC_PER_CPU
   7#ifdef CONFIG_SMP
   8
   9extern unsigned long __per_cpu_offset[NR_CPUS];
  10
  11#define per_cpu_offset(x) (__per_cpu_offset[x])
  12
  13/* Separate out the type, so (int[3], foo) works. */
  14#define DEFINE_PER_CPU(type, name) \
  15    __attribute__((__section__(".data.percpu"))) __typeof__(type) per_cpu__##name
  16
  17#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name)               \
  18    __attribute__((__section__(".data.percpu.shared_aligned"))) \
  19    __typeof__(type) per_cpu__##name                            \
  20    ____cacheline_aligned_in_smp
  21
  22/* var is in discarded region: offset to particular copy we want */
  23#define per_cpu(var, cpu) (*({                          \
  24        extern int simple_identifier_##var(void);       \
  25        RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]); }))
  26#define __get_cpu_var(var) per_cpu(var, smp_processor_id())
  27#define __raw_get_cpu_var(var) per_cpu(var, raw_smp_processor_id())
  28
  29/* A macro to avoid #include hell... */
  30#define percpu_modcopy(pcpudst, src, size)                      \
  31do {                                                            \
  32        unsigned int __i;                                       \
  33        for_each_possible_cpu(__i)                              \
  34                memcpy((pcpudst)+__per_cpu_offset[__i],         \
  35                       (src), (size));                          \
  36} while (0)
  37#else /* ! SMP */
  38
  39#define DEFINE_PER_CPU(type, name) \
  40    __typeof__(type) per_cpu__##name
  41
  42#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name)       \
  43    DEFINE_PER_CPU(type, name)
  44
  45#define per_cpu(var, cpu)                       (*((void)(cpu), &per_cpu__##var))
  46#define __get_cpu_var(var)                      per_cpu__##var
  47#define __raw_get_cpu_var(var)                  per_cpu__##var
  48
  49#endif  /* SMP */
  50
  51#define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
  52
  53#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
  54#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
  55
  56#endif /* _ASM_GENERIC_PERCPU_H_ */
  57