include/asm-generic/percpu.h

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