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#ifndef __ALPHA_PERCPU_H
#define __ALPHA_PERCPU_H
#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.
*/
extern unsigned long __per_cpu_offset[NR_CPUS];
#define per_cpu_offset(x) (__per_cpu_offset[x])
#define __my_cpu_offset per_cpu_offset(raw_smp_processor_id())
#ifdef CONFIG_DEBUG_PREEMPT
#define my_cpu_offset per_cpu_offset(smp_processor_id())
#else
#define my_cpu_offset __my_cpu_offset
#endif
#ifndef MODULE
#define SHIFT_PERCPU_PTR(var, offset) RELOC_HIDE(&per_cpu_var(var), (offset))
#define PER_CPU_ATTRIBUTES
#else
/*
* To calculate addresses of locally defined variables, GCC uses 32-bit
* displacement from the GP. Which doesn't work for per cpu variables in
* modules, as an offset to the kernel per cpu area is way above 4G.
*
* This forces allocation of a GOT entry for per cpu variable using
* ldq instruction with a 'literal' relocation.
*/
#define SHIFT_PERCPU_PTR(var, offset) ({ \
extern int simple_identifier_##var(void); \
unsigned long __ptr, tmp_gp; \
asm ( "br %1, 1f \n\
1: ldgp %1, 0(%1) \n\
ldq %0, per_cpu__" #var"(%1)\t!literal" \
: "=&r"(__ptr), "=&r"(tmp_gp)); \
(typeof(&per_cpu_var(var)))(__ptr + (offset)); })
#define PER_CPU_ATTRIBUTES __used
#endif /* MODULE */
/*
* 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(var, per_cpu_offset(cpu)))
#define __get_cpu_var(var) \
(*SHIFT_PERCPU_PTR(var, my_cpu_offset))
#define __raw_get_cpu_var(var) \
(*SHIFT_PERCPU_PTR(var, __my_cpu_offset))
#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)
#define PER_CPU_ATTRIBUTES
#endif /* SMP */
#define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu_var(name)
#endif /* __ALPHA_PERCPU_H */
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