但是,我对hrtimer在linux内核中的工作方式有点困惑(参见linux / hrtimer.h).我知道时间是指定的,回调应该返回HRTIMER_RESTART或HRTIMER_NORESTART.我在网上找到了一些资料,说明需要使用hrtimer_forward方法在回调中重置计时器.然而,我所看到的消息来源对于如何增加时间有点不清楚.这是我到目前为止的代码：

static struct hrtimer timer;

static enum hrtimer_restart timer_callback(struct hrtimer *timer)
{
    printk(KERN_ERR "Callback\n");
    //I know something needs to go here to reset the timer
    return HRTIMER_RESTART;
}

static int init_timer(void)
{   
    ktime_t ktime;
    unsigned long delay_in_ms = 500L;
    printk(KERN_ERR "Timer being set up\n");

    ktime = ktime_set(0,delay_in_ms*1E6L);
    hrtimer_init(&timer,CLOCK_MONOTONIC,HRTIMER_MODE_REL);

    timer.function = &timer_callback;
    printk(KERN_ERR "Timer starting to fire\n");
    printk(KERN_ERR "in %ldms %ld\n",delay_in_ms,jiffies);

    hrtimer_start(&timer,ktime,HRTIMER_MODE_REL);
    return 0;
}

static void clean_load_balancing_timer(void)
{
    int cancelled = hrtimer_cancel(&timer);

    if (cancelled)
        printk(KERN_ERR "Timer still running\n");
    else
        printk(KERN_ERR "Timer cancelled\n");
}

有人能解释一下重置计时器在回调函数中的作用吗？谢谢！