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#ifndef _ASM_X86_PERCPU_H
#define _ASM_X86_PERCPU_H
#ifdef CONFIG_X86_64
#define __percpu_seg gs
#define __percpu_mov_op movq
#else
#define __percpu_seg fs
#define __percpu_mov_op movl
#endif
#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) \
__percpu_mov_op %__percpu_seg:per_cpu__this_cpu_off, reg; \
lea per_cpu__##var(reg), reg
#define PER_CPU_VAR(var) %__percpu_seg:per_cpu__##var
#else /* ! SMP */
#define PER_CPU(var, reg) \
__percpu_mov_op $per_cpu__##var, reg
#define PER_CPU_VAR(var) per_cpu__##var
#endif /* SMP */
#ifdef CONFIG_X86_64_SMP
#define INIT_PER_CPU_VAR(var) init_per_cpu__##var
#else
#define INIT_PER_CPU_VAR(var) per_cpu__##var
#endif
#else /* ...!ASSEMBLY */
#include <linux/kernel.h>
#include <linux/stringify.h>
#ifdef CONFIG_SMP
#define __percpu_arg(x) "%%"__stringify(__percpu_seg)":%P" #x
#define __my_cpu_offset percpu_read(this_cpu_off)
#else
#define __percpu_arg(x) "%P" #x
#endif
/*
* Initialized pointers to per-cpu variables needed for the boot
* processor need to use these macros to get the proper address
* offset from __per_cpu_load on SMP.
*
* There also must be an entry in vmlinux_64.lds.S
*/
#define DECLARE_INIT_PER_CPU(var) \
extern typeof(per_cpu_var(var)) init_per_cpu_var(var)
#ifdef CONFIG_X86_64_SMP
#define init_per_cpu_var(var) init_per_cpu__##var
#else
#define init_per_cpu_var(var) per_cpu_var(var)
#endif
/* 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_arg(0) \
: "+m" (var) \
: "qi" ((T__)(val))); \
break; \
case 2: \
asm(op "w %1,"__percpu_arg(0) \
: "+m" (var) \
: "ri" ((T__)(val))); \
break; \
case 4: \
asm(op "l %1,"__percpu_arg(0) \
: "+m" (var) \
: "ri" ((T__)(val))); \
break; \
case 8: \
asm(op "q %1,"__percpu_arg(0) \
: "+m" (var) \
: "re" ((T__)(val))); \
break; \
default: __bad_percpu_size(); \
} \
} while (0)
#define percpu_from_op(op, var, constraint) \
({ \
typeof(var) ret__; \
switch (sizeof(var)) { \
case 1: \
asm(op "b "__percpu_arg(1)",%0" \
: "=q" (ret__) \
: constraint); \
break; \
case 2: \
asm(op "w "__percpu_arg(1)",%0" \
: "=r" (ret__) \
: constraint); \
break; \
case 4: \
asm(op "l "__percpu_arg(1)",%0" \
: "=r" (ret__) \
: constraint); \
break; \
case 8: \
asm(op "q "__percpu_arg(1)",%0" \
: "=r" (ret__) \
: constraint); \
break; \
default: __bad_percpu_size(); \
} \
ret__; \
})
/*
* percpu_read() makes gcc load the percpu variable every time it is
* accessed while percpu_read_stable() allows the value to be cached.
* percpu_read_stable() is more efficient and can be used if its value
* is guaranteed to be valid across cpus. The current users include
* get_current() and get_thread_info() both of which are actually
* per-thread variables implemented as per-cpu variables and thus
* stable for the duration of the respective task.
*/
#define percpu_read(var) percpu_from_op("mov", per_cpu__##var, \
"m" (per_cpu__##var))
#define percpu_read_stable(var) percpu_from_op("mov", per_cpu__##var, \
"p" (&per_cpu__##var))
#define percpu_write(var, val) percpu_to_op("mov", per_cpu__##var, val)
#define percpu_add(var, val) percpu_to_op("add", per_cpu__##var, val)
#define percpu_sub(var, val) percpu_to_op("sub", per_cpu__##var, val)
#define percpu_and(var, val) percpu_to_op("and", per_cpu__##var, val)
#define percpu_or(var, val) percpu_to_op("or", per_cpu__##var, val)
#define percpu_xor(var, val) percpu_to_op("xor", per_cpu__##var, val)
/* This is not atomic against other CPUs -- CPU preemption needs to be off */
#define x86_test_and_clear_bit_percpu(bit, var) \
({ \
int old__; \
asm volatile("btr %2,"__percpu_arg(1)"\n\tsbbl %0,%0" \
: "=r" (old__), "+m" (per_cpu__##var) \
: "dIr" (bit)); \
old__; \
})
#include <asm-generic/percpu.h>
/* We can use this directly for local CPU (faster). */
DECLARE_PER_CPU(unsigned long, this_cpu_off);
#endif /* !__ASSEMBLY__ */
#ifdef CONFIG_SMP
/*
* Define the "EARLY_PER_CPU" macros. These are used for some per_cpu
* variables that are initialized and accessed before there are per_cpu
* areas allocated.
*/
#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
DEFINE_PER_CPU(_type, _name) = _initvalue; \
__typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
{ [0 ... NR_CPUS-1] = _initvalue }; \
__typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
EXPORT_PER_CPU_SYMBOL(_name)
#define DECLARE_EARLY_PER_CPU(_type, _name) \
DECLARE_PER_CPU(_type, _name); \
extern __typeof__(_type) *_name##_early_ptr; \
extern __typeof__(_type) _name##_early_map[]
#define early_per_cpu_ptr(_name) (_name##_early_ptr)
#define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
#define early_per_cpu(_name, _cpu) \
*(early_per_cpu_ptr(_name) ? \
&early_per_cpu_ptr(_name)[_cpu] : \
&per_cpu(_name, _cpu))
#else /* !CONFIG_SMP */
#define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
DEFINE_PER_CPU(_type, _name) = _initvalue
#define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
EXPORT_PER_CPU_SYMBOL(_name)
#define DECLARE_EARLY_PER_CPU(_type, _name) \
DECLARE_PER_CPU(_type, _name)
#define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
#define early_per_cpu_ptr(_name) NULL
/* no early_per_cpu_map() */
#endif /* !CONFIG_SMP */
#endif /* _ASM_X86_PERCPU_H */
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