X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=include%2Fasm-generic%2Fpercpu.h;h=b0e63c672ebdf5a065ddea3374558a9638bc43c1;hb=fac296322c838e8dd425b13410ff7ada2856a8ee;hp=d85172e9ed4580afa55c333e49fcb2ee925403db;hpb=fdb64f93b38a3470fa4db8cd5720b8c731922d1a;p=linux-2.6-omap-h63xx.git diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h index d85172e9ed4..b0e63c672eb 100644 --- a/include/asm-generic/percpu.h +++ b/include/asm-generic/percpu.h @@ -3,54 +3,81 @@ #include #include -#define __GENERIC_PER_CPU +/* + * Determine the real variable name from the name visible in the + * kernel sources. + */ +#define per_cpu_var(var) per_cpu__##var + #ifdef CONFIG_SMP +/* + * per_cpu_offset() is the offset that has to be added to a + * percpu variable to get to the instance for a certain processor. + * + * Most arches use the __per_cpu_offset array for those offsets but + * some arches have their own ways of determining the offset (x86_64, s390). + */ +#ifndef __per_cpu_offset extern unsigned long __per_cpu_offset[NR_CPUS]; #define per_cpu_offset(x) (__per_cpu_offset[x]) +#endif -/* Separate out the type, so (int[3], foo) works. */ -#define DEFINE_PER_CPU(type, name) \ - __attribute__((__section__(".data.percpu"))) __typeof__(type) per_cpu__##name - -#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \ - __attribute__((__section__(".data.percpu.shared_aligned"))) \ - __typeof__(type) per_cpu__##name \ - ____cacheline_aligned_in_smp - -/* var is in discarded region: offset to particular copy we want */ -#define per_cpu(var, cpu) (*({ \ - extern int simple_identifier_##var(void); \ - RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]); })) -#define __get_cpu_var(var) per_cpu(var, smp_processor_id()) -#define __raw_get_cpu_var(var) per_cpu(var, raw_smp_processor_id()) - -/* A macro to avoid #include hell... */ -#define percpu_modcopy(pcpudst, src, size) \ -do { \ - unsigned int __i; \ - for_each_possible_cpu(__i) \ - memcpy((pcpudst)+__per_cpu_offset[__i], \ - (src), (size)); \ -} while (0) -#else /* ! SMP */ +/* + * Determine the offset for the currently active processor. + * An arch may define __my_cpu_offset to provide a more effective + * means of obtaining the offset to the per cpu variables of the + * current processor. + */ +#ifndef __my_cpu_offset +#define __my_cpu_offset per_cpu_offset(raw_smp_processor_id()) +#endif +#ifdef CONFIG_DEBUG_PREEMPT +#define my_cpu_offset per_cpu_offset(smp_processor_id()) +#else +#define my_cpu_offset __my_cpu_offset +#endif + +/* + * Add a offset to a pointer but keep the pointer as is. + * + * Only S390 provides its own means of moving the pointer. + */ +#ifndef SHIFT_PERCPU_PTR +#define SHIFT_PERCPU_PTR(__p, __offset) RELOC_HIDE((__p), (__offset)) +#endif -#define DEFINE_PER_CPU(type, name) \ - __typeof__(type) per_cpu__##name +/* + * A percpu variable may point to a discarded regions. The following are + * established ways to produce a usable pointer from the percpu variable + * offset. + */ +#define per_cpu(var, cpu) \ + (*SHIFT_PERCPU_PTR(&per_cpu_var(var), per_cpu_offset(cpu))) +#define __get_cpu_var(var) \ + (*SHIFT_PERCPU_PTR(&per_cpu_var(var), my_cpu_offset)) +#define __raw_get_cpu_var(var) \ + (*SHIFT_PERCPU_PTR(&per_cpu_var(var), __my_cpu_offset)) -#define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \ - DEFINE_PER_CPU(type, name) -#define per_cpu(var, cpu) (*((void)(cpu), &per_cpu__##var)) -#define __get_cpu_var(var) per_cpu__##var -#define __raw_get_cpu_var(var) per_cpu__##var +#ifdef CONFIG_HAVE_SETUP_PER_CPU_AREA +extern void setup_per_cpu_areas(void); +#endif + +#else /* ! SMP */ + +#define per_cpu(var, cpu) (*((void)(cpu), &per_cpu_var(var))) +#define __get_cpu_var(var) per_cpu_var(var) +#define __raw_get_cpu_var(var) per_cpu_var(var) #endif /* SMP */ -#define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name +#ifndef PER_CPU_ATTRIBUTES +#define PER_CPU_ATTRIBUTES +#endif -#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var) -#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var) +#define DECLARE_PER_CPU(type, name) extern PER_CPU_ATTRIBUTES \ + __typeof__(type) per_cpu_var(name) #endif /* _ASM_GENERIC_PERCPU_H_ */