_workqueue_submit_work 函数有概率返回-RT_EBUSY

发布于 2022-03-28 23:39:50 浏览：614 订阅该版

```
static rt_err_t _workqueue_submit_work(struct rt_workqueue *queue,
        struct rt_work *work, rt_tick_t ticks)
{
    rt_base_t level;
    rt_err_t err;

level = rt_hw_interrupt_disable();
    /* remove list */
    rt_list_remove(&(work->list));
    work->flags &= ~RT_WORK_STATE_PENDING;
    /*  */
    if (ticks == 0)
    {
        if (queue->work_current != work)
        {
            rt_list_insert_after(queue->work_list.prev, &(work->list));
            work->flags |= RT_WORK_STATE_PENDING;
            work->workqueue = queue;
            err = RT_EOK;
        }
        else
        {
            err = -RT_EBUSY;
        }

/* whether the workqueue is doing work */
        if (queue->work_current == RT_NULL &&
            ((queue->work_thread->stat & RT_THREAD_STAT_MASK) == RT_THREAD_SUSPEND))
        {
            /* resume work thread */
            rt_thread_resume(queue->work_thread);
            rt_hw_interrupt_enable(level);
            rt_schedule();
        }
        else
        {
            rt_hw_interrupt_enable(level);
        }
        return err;
    }
    else if (ticks < RT_TICK_MAX / 2)
    {
        /* Timer started */
        if (work->flags & RT_WORK_STATE_SUBMITTING)
        {
            rt_timer_stop(&work->timer);
            rt_timer_control(&work->timer, RT_TIMER_CTRL_SET_TIME, &ticks);
        }
        else
        {
            rt_timer_init(&(work->timer), "work", _delayed_work_timeout_handler,
                        work, ticks, RT_TIMER_FLAG_ONE_SHOT | RT_TIMER_FLAG_SOFT_TIMER);
            work->flags |= RT_WORK_STATE_SUBMITTING;
        }
        work->workqueue = queue;
        /* insert delay work list */
        rt_list_insert_after(queue->delayed_list.prev, &(work->list));
        rt_hw_interrupt_enable(level);
        rt_timer_start(&(work->timer));
        return RT_EOK;
    }
    rt_hw_interrupt_enable(level);
    return -RT_ERROR;
}
```
在调试wlan框架时，频繁的wifi断线重连，可能会使某些wlan事件在执行到 _workqueue_submit_work函数时返回-RT_EBUSY，此时会打印如下日志
![微信截图_20220328233729.png](https://oss-club.rt-thread.org/uploads/20220328/7e268857b8f138621897a21bb77d3d0f.png)

经测试，可能是因为 queue->work_current 会在执行完work函数后才会清空，如果在任务函数内 free 相应的work对象，之后线程进行调度，在别的线程中重新执行malloc申请work对象内存，有概率会使得 if (queue->work_current != work) 判断条件不成立，因而返回 -RT_EBUSY 错误码