define new percpu interface for shared data
[linux-2.6.git] / 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
9 extern 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)                      \
31 do {                                                            \
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_ */