xref: /linux/include/asm-generic/percpu.h (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
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 #define per_cpu_offset(x) (__per_cpu_offset[x])
11 
12 /* Separate out the type, so (int[3], foo) works. */
13 #define DEFINE_PER_CPU(type, name) \
14     __attribute__((__section__(".data.percpu"))) __typeof__(type) per_cpu__##name
15 
16 /* var is in discarded region: offset to particular copy we want */
17 #define per_cpu(var, cpu) (*({				\
18 	extern int simple_identifier_##var(void);	\
19 	RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]); }))
20 #define __get_cpu_var(var) per_cpu(var, smp_processor_id())
21 #define __raw_get_cpu_var(var) per_cpu(var, raw_smp_processor_id())
22 
23 /* A macro to avoid #include hell... */
24 #define percpu_modcopy(pcpudst, src, size)			\
25 do {								\
26 	unsigned int __i;					\
27 	for_each_possible_cpu(__i)				\
28 		memcpy((pcpudst)+__per_cpu_offset[__i],		\
29 		       (src), (size));				\
30 } while (0)
31 #else /* ! SMP */
32 
33 #define DEFINE_PER_CPU(type, name) \
34     __typeof__(type) per_cpu__##name
35 
36 #define per_cpu(var, cpu)			(*((void)(cpu), &per_cpu__##var))
37 #define __get_cpu_var(var)			per_cpu__##var
38 #define __raw_get_cpu_var(var)			per_cpu__##var
39 
40 #endif	/* SMP */
41 
42 #define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
43 
44 #define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
45 #define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
46 
47 #endif /* _ASM_GENERIC_PERCPU_H_ */
48