另:test_and_set_bit(unsigned long nr, volatile unsigned long *addr) 设置第nr位,从右边0位开始,并返回原值。 test_and_clear_bit(unsigned long nr, volatile unsigned long *addr) 清除第nr位,从0位开始数。 set_bit(int nr, volatile unsigned long *addr) clear_bit(int nr, volatile unsigned long *addr) change_bit(int nr, volatile unsigned long *addr)