rt_thread_delay_until函数运行几个小时后线程不再被执行

发布于 2024-07-30 15:24:03 浏览：409 订阅该版

1 个回答

liuyue9793 2024-08-06

这家伙很懒，什么也没写！

经过几天的调试发现rt_thread_delay_until函数存在问题，下面是问题的一个简单分析。

```c

rt_err_t rt_thread_delay_until(rt_tick_t *tick, rt_tick_t inc_tick)
{
    rt_base_t level;
    struct rt_thread *thread;
    rt_tick_t cur_tick;

RT_ASSERT(tick != RT_NULL);

/* set to current thread */
    thread = rt_thread_self();
    RT_ASSERT(thread != RT_NULL);
    RT_ASSERT(rt_object_get_type((rt_object_t)thread) == RT_Object_Class_Thread);

/* disable interrupt */
    level = rt_spin_lock_irqsave(&(thread->spinlock));

/* reset thread error */
    thread->error = RT_EOK;

cur_tick = rt_tick_get();
    if (cur_tick - *tick < inc_tick)
    {
        thread->user_data = 1;
        rt_tick_t left_tick;

*tick += inc_tick;
        left_tick = *tick - cur_tick;

rt_spin_unlock_irqrestore(&(thread->spinlock), level);
        /* suspend thread */
        rt_thread_suspend_with_flag(thread, RT_UNINTERRUPTIBLE);
        level = rt_spin_lock_irqsave(&(thread->spinlock));

/* reset the timeout of thread timer and start it */
        rt_timer_control(&(thread->thread_timer), RT_TIMER_CTRL_SET_TIME, &left_tick);
        rt_timer_start(&(thread->thread_timer));
        rt_spin_unlock_irqrestore(&(thread->spinlock), level);

rt_schedule();
        /* clear error number of this thread to RT_EOK */
        if (thread->error == -RT_ETIMEOUT)
        {
            thread->error = RT_EOK;
        }
    }
    else
    {
        *tick = cur_tick;
        rt_spin_unlock_irqrestore(&(thread->spinlock), level);
    }

return thread->error;
}

```
在上面的代码中rt_thread_suspend_with_flag函数的调用环境并没有关中断，导致串口中断在该函数返回的过程中打断了线程的执行。
串口中断会调用rt_schedule函数，该函数导致中断返回后原来执行的线程被挂起，后面启动定时器的代码无法被执行，线程也无法通过timeout函数被重新启动，该线程将永远挂起无法执行。

![screenshot_image.png](https://oss-club.rt-thread.org/uploads/20240806/f36a4b6cf4609d027942714b4a424f0a.png)