linux/include/asm-x86/percpu.h

143 lines
3.5 KiB
C

#ifndef _ASM_X86_PERCPU_H_
#define _ASM_X86_PERCPU_H_
#ifdef CONFIG_X86_64
#include <linux/compiler.h>
/* Same as asm-generic/percpu.h, except that we store the per cpu offset
in the PDA. Longer term the PDA and every per cpu variable
should be just put into a single section and referenced directly
from %gs */
#ifdef CONFIG_SMP
#include <asm/pda.h>
#define __per_cpu_offset(cpu) (cpu_pda(cpu)->data_offset)
#define __my_cpu_offset read_pda(data_offset)
#define per_cpu_offset(x) (__per_cpu_offset(x))
#endif
#include <asm-generic/percpu.h>
DECLARE_PER_CPU(struct x8664_pda, pda);
#else /* CONFIG_X86_64 */
#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; \
lea per_cpu__##var(reg), reg
#define PER_CPU_VAR(var) %fs:per_cpu__##var
#else /* ! SMP */
#define PER_CPU(var, reg) \
movl $per_cpu__##var, reg
#define PER_CPU_VAR(var) per_cpu__##var
#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
#define __my_cpu_offset x86_read_percpu(this_cpu_off)
/* fs segment starts at (positive) offset == __per_cpu_offset[cpu] */
#define __percpu_seg "%%fs:"
#else /* !SMP */
#define __percpu_seg ""
#endif /* SMP */
#include <asm-generic/percpu.h>
/* We can use this directly for local CPU (faster). */
DECLARE_PER_CPU(unsigned long, this_cpu_off);
/* 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 /* !CONFIG_X86_64 */
#endif /* _ASM_X86_PERCPU_H_ */