Kernel

RTT rt_timer_check 疑惑

发布于 2019-09-23 15:49:16 浏览：1783 订阅该版

2 个回答

sync 2019-09-23

这家伙很懒，什么也没写！

李玉航 2022-05-09

这家伙很懒，什么也没写！

```c
for (row_lvl = 0; row_lvl < RT_TIMER_SKIP_LIST_LEVEL; row_lvl++)
    {
        for (; row_head[row_lvl] != timer_list[row_lvl].prev;
             row_head[row_lvl]  = row_head[row_lvl]->next)
        {
            struct rt_timer *t;
            rt_list_t *p = row_head[row_lvl]->next;

/* fix up the entry pointer */
            t = rt_list_entry(p, struct rt_timer, row[row_lvl]);

/* If we have two timers that timeout at the same time, it's
             * preferred that the timer inserted early get called early.
             * So insert the new timer to the end the the some-timeout timer
             * list.
             */
            if ((t->timeout_tick - timer->timeout_tick) == 0)
            {
                continue;
            }
            else if ((t->timeout_tick - timer->timeout_tick) < RT_TICK_MAX / 2)
            {
                break;
            }
        }
        if (row_lvl != RT_TIMER_SKIP_LIST_LEVEL - 1)
            row_head[row_lvl + 1] = row_head[row_lvl] + 1;
    }

```

会根据下面代码进行排序，和@sync 说的一样，下一个到达的肯定是最近的定时器（任务）
```c
if ((t->timeout_tick - timer->timeout_tick) == 0)
{
    continue;
}
else if ((t->timeout_tick - timer->timeout_tick) < RT_TICK_MAX / 2)
{
    break;
}
```