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#ifndef __ASM_SYSTEM_H
#define __ASM_SYSTEM_H
#include <asm/segment.h>
#include <asm/cpufeature.h>
#include <asm/cmpxchg.h>
#ifdef __KERNEL__
#define AT_VECTOR_SIZE_ARCH 2 /* entries in ARCH_DLINFO */
struct task_struct; /* one of the stranger aspects of C forward declarations.. */
extern struct task_struct * FASTCALL(__switch_to(struct task_struct *prev, struct task_struct *next));
/*
* Saving eflags is important. It switches not only IOPL between tasks,
* it also protects other tasks from NT leaking through sysenter etc.
*/
#define switch_to(prev,next,last) do { \
unsigned long esi,edi; \
asm volatile("pushfl\n\t" /* Save flags */ \
"pushl %%ebp\n\t" \
"movl %%esp,%0\n\t" /* save ESP */ \
"movl %5,%%esp\n\t" /* restore ESP */ \
"movl $1f,%1\n\t" /* save EIP */ \
"pushl %6\n\t" /* restore EIP */ \
"jmp __switch_to\n" \
"1:\t" \
"popl %%ebp\n\t" \
"popfl" \
:"=m" (prev->thread.sp),"=m" (prev->thread.ip), \
"=a" (last),"=S" (esi),"=D" (edi) \
:"m" (next->thread.sp),"m" (next->thread.ip), \
"2" (prev), "d" (next)); \
} while (0)
#endif /* __KERNEL__ */
#include <linux/irqflags.h>
/*
* disable hlt during certain critical i/o operations
*/
#define HAVE_DISABLE_HLT
#endif
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