ssize_t my_read(struct file *flip,char __user *buff,size_t cnt,loff_t *off_t)
{
    spin_lock_irqsave(&my_spinlock,flag);
        /* 变量number是要保护的数据*/
    if(copy_to_user(buff,&number,sizeof(int)))
    {
        spin_unlock_irqrestore(&my_spinlock,flag);
        return -EFAULT;
    }
    /*延时10秒，为并发创造条件*/
        ssleep(10);
    spin_unlock_irqrestore(&my_spinlock,flag);
    return 0;
}
ssize_t my_write(struct file *flip,const char __user *buff,size_t cnt,loff_t *off_t)
{
    spin_lock_irqsave(&my_spinlock,flag);

    if(copy_from_user(&number,buff,sizeof(int)))
    {
        spin_unlock_irqrestore(&my_spinlock,flag);
        return -EFAULT;
    }
    spin_unlock_irqrestore(&my_spinlock,flag);
    return 0;
}