1. 根目录:
2. arch
3. x86
4. include
5. uapi
6. asm
7. ucontext.h

#ifndef _ASM_X86_UCONTEXT_H
#define _ASM_X86_UCONTEXT_H

#define UC_FP_XSTATE	0x1	/* indicates the presence of extended state
				 * information in the memory layout pointed
				 * by the fpstate pointer in the ucontext's
				 * sigcontext struct (uc_mcontext).
				 */

#include <asm-generic/ucontext.h>

#endif /* _ASM_X86_UCONTEXT_H */