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#ifndef __ARCH_I386_PERCPU__
#define __ARCH_I386_PERCPU__
#ifdef __ASSEMBLY__
/*
* PER_CPU finds an address of a per-cpu variable.
*
* Args:
* var - variable name
* reg - 32bit register
*
* The resulting address is stored in the "reg" argument.
*
* Example:
* PER_CPU(cpu_gdt_descr, %ebx)
*/
#ifdef CONFIG_SMP
#define PER_CPU(var, reg) \
movl %fs:per_cpu__this_cpu_off, reg; \
addl $per_cpu__##var, reg
#else /* ! SMP */
#define PER_CPU(var, reg) \
movl $per_cpu__##var, reg;
#endif /* SMP */
#else /* ...!ASSEMBLY */
/*
* PER_CPU finds an address of a per-cpu variable.
*
* Args:
* var - variable name
* cpu - 32bit register containing the current CPU number
*
* The resulting address is stored in the "cpu" argument.
*
* Example:
* PER_CPU(cpu_gdt_descr, %ebx)
*/
#ifdef CONFIG_SMP
/* Same as generic implementation except for optimized local access. */
#define __GENERIC_PER_CPU
/* This is used for other cpus to find our section. */
extern unsigned long __per_cpu_offset[];
/* Separate out the type, so (int[3], foo) works. */
#define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
#define DEFINE_PER_CPU(type, name) \
__attribute__((__section__(".data.percpu"))) __typeof__(type) per_cpu__##name
/* We can use this directly for local CPU (faster). */
DECLARE_PER_CPU(unsigned long, this_cpu_off);
/* var is in discarded region: offset to particular copy we want */
#define per_cpu(var, cpu) (*({ \
extern int simple_indentifier_##var(void); \
RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]); }))
#define __raw_get_cpu_var(var) (*({ \
extern int simple_indentifier_##var(void); \
RELOC_HIDE(&per_cpu__##var, x86_read_percpu(this_cpu_off)); \
}))
#define __get_cpu_var(var) __raw_get_cpu_var(var)
/* 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)
#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
/* fs segment starts at (positive) offset == __per_cpu_offset[cpu] */
#define __percpu_seg "%%fs:"
#else /* !SMP */
#include <asm-generic/percpu.h>
#define __percpu_seg ""
#endif /* SMP */
/* For arch-specific code, we can use direct single-insn ops (they
* don't give an lvalue though). */
extern void __bad_percpu_size(void);
#define percpu_to_op(op,var,val) \
do { \
typedef typeof(var) T__; \
if (0) { T__ tmp__; tmp__ = (val); } \
switch (sizeof(var)) { \
case 1: \
asm(op "b %1,"__percpu_seg"%0" \
: "+m" (var) \
:"ri" ((T__)val)); \
break; \
case 2: \
asm(op "w %1,"__percpu_seg"%0" \
: "+m" (var) \
:"ri" ((T__)val)); \
break; \
case 4: \
asm(op "l %1,"__percpu_seg"%0" \
: "+m" (var) \
:"ri" ((T__)val)); \
break; \
default: __bad_percpu_size(); \
} \
} while (0)
#define percpu_from_op(op,var) \
({ \
typeof(var) ret__; \
switch (sizeof(var)) { \
case 1: \
asm(op "b "__percpu_seg"%1,%0" \
: "=r" (ret__) \
: "m" (var)); \
break; \
case 2: \
asm(op "w "__percpu_seg"%1,%0" \
: "=r" (ret__) \
: "m" (var)); \
break; \
case 4: \
asm(op "l "__percpu_seg"%1,%0" \
: "=r" (ret__) \
: "m" (var)); \
break; \
default: __bad_percpu_size(); \
} \
ret__; })
#define x86_read_percpu(var) percpu_from_op("mov", per_cpu__##var)
#define x86_write_percpu(var,val) percpu_to_op("mov", per_cpu__##var, val)
#define x86_add_percpu(var,val) percpu_to_op("add", per_cpu__##var, val)
#define x86_sub_percpu(var,val) percpu_to_op("sub", per_cpu__##var, val)
#define x86_or_percpu(var,val) percpu_to_op("or", per_cpu__##var, val)
#endif /* !__ASSEMBLY__ */
#endif /* __ARCH_I386_PERCPU__ */
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