diff options
| -rw-r--r-- | arch/ia64/kernel/module.c | 2 | ||||
| -rw-r--r-- | include/asm-generic/percpu.h | 74 |
2 files changed, 64 insertions, 12 deletions
diff --git a/arch/ia64/kernel/module.c b/arch/ia64/kernel/module.c index 196287928bae..e699eb6c44be 100644 --- a/arch/ia64/kernel/module.c +++ b/arch/ia64/kernel/module.c @@ -947,7 +947,7 @@ percpu_modcopy (void *pcpudst, const void *src, unsigned long size) { unsigned int i; for_each_possible_cpu(i) { - memcpy(pcpudst + __per_cpu_offset[i], src, size); + memcpy(pcpudst + per_cpu_offset(i), src, size); } } #endif /* CONFIG_SMP */ diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h index e038f13594e5..c41b1a731129 100644 --- a/include/asm-generic/percpu.h +++ b/include/asm-generic/percpu.h @@ -3,35 +3,87 @@ #include <linux/compiler.h> #include <linux/threads.h> +/* + * 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 + +/* + * 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()) +#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 -/* 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 percpu variable may point to a discarded reghions. 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)) + + +#ifdef CONFIG_ARCH_SETS_UP_PER_CPU_AREA +extern void setup_per_cpu_areas(void); +#endif /* 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], \ + memcpy((pcpudst)+per_cpu_offset(__i), \ (src), (size)); \ } while (0) #else /* ! SMP */ -#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 +#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 DECLARE_PER_CPU(type, name) extern PER_CPU_ATTRIBUTES \ + __typeof__(type) per_cpu_var(name) #endif /* _ASM_GENERIC_PERCPU_H_ */ |
