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 #ifdef CONFIG_SMP
   7
   8 extern unsigned long __per_cpu_offset[NR_CPUS];
   9
  10 #define per_cpu_offset(x) (__per_cpu_offset[x])
  11
  12 /* var is in discarded region: offset to particular copy we want */
  13 #define per_cpu(var, cpu) (*({                          \
  14         extern int simple_identifier_##var(void);       \
  15         RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]); }))
  16 #define __get_cpu_var(var) per_cpu(var, smp_processor_id())
  17 #define __raw_get_cpu_var(var) per_cpu(var, raw_smp_processor_id())
  18
  19 /* A macro to avoid #include hell... */
  20 #define percpu_modcopy(pcpudst, src, size)                      \
  21 do {                                                            \
  22         unsigned int __i;                                       \
  23         for_each_possible_cpu(__i)                              \
  24                 memcpy((pcpudst)+__per_cpu_offset[__i],         \
  25                        (src), (size));                          \
  26 } while (0)
  27 #else /* ! SMP */
  28
  29 #define per_cpu(var, cpu)                       (*((void)(cpu), &per_cpu__##var))
  30 #define __get_cpu_var(var)                      per_cpu__##var
  31 #define __raw_get_cpu_var(var)                  per_cpu__##var
  32
  33 #endif  /* SMP */
  34
  35 #define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
  36
  37 #endif /* _ASM_GENERIC_PERCPU_H_ */