1. 根目录:
2. include
3. asm-generic
4. bitops.h

#ifndef __ASM_GENERIC_BITOPS_H
#define __ASM_GENERIC_BITOPS_H

/*
 * For the benefit of those who are trying to port Linux to another
 * architecture, here are some C-language equivalents.  You should
 * recode these in the native assembly language, if at all possible.
 *
 * C language equivalents written by Theodore Ts'o, 9/26/92
 */

#include <linux/irqflags.h>
#include <linux/compiler.h>

/*
 * clear_bit may not imply a memory barrier
 */
#ifndef smp_mb__before_clear_bit
#define smp_mb__before_clear_bit()	smp_mb()
#define smp_mb__after_clear_bit()	smp_mb()
#endif

#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/ffz.h>
#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/find.h>

#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif

#include <asm-generic/bitops/sched.h>
#include <asm-generic/bitops/ffs.h>
#include <asm-generic/bitops/hweight.h>
#include <asm-generic/bitops/lock.h>

#include <asm-generic/bitops/atomic.h>
#include <asm-generic/bitops/non-atomic.h>
#include <asm-generic/bitops/le.h>
#include <asm-generic/bitops/ext2-atomic.h>

#endif /* __ASM_GENERIC_BITOPS_H */