闫刚 nuttx的work队列实现原理
作者:互联网
工作队列实现
优点:最短时间调度
缺点:工作队列执行完后,需要重新创建.
添加工作对象
static int work_qqueue(FAR struct usr_wqueue_s *wqueue,
FAR struct work_s *work, worker_t worker,
FAR void *arg, systime_t delay)
-> dq_addlast((FAR dq_entry_t *)work, &wqueue->q);
工作队列执行进程
void work_process(FAR struct kwork_wqueue_s *wqueue, systime_t period, int wndx)
{
work = (FAR struct work_s *)wqueue->q.head;
while (work)
ctick = clock_systimer();
elapsed = ctick - work->qtime;
if (elapsed >= work->delay)
{
//时间到了,就执行这个节点, 执行完后,立即删除这个节点,
(void)dq_rem((struct dq_entry_s *)work, &wqueue->q);
work = (FAR struct work_s *)wqueue->q.head;
worker(arg); //执行函数
else /* elapsed < work->delay */
{
//找到需要等待最短时间的那个节点。
elapsed += (ctick - stick);
if (elapsed > work->delay)
{
elapsed = work->delay;
remaining = work->delay - elapsed;
if (remaining < next)
{
next = remaining;
}
work = (FAR struct work_s *)work->dq.flink;
//工作队列的对象的时间小于hpwork队列时间,则使用任务调用的时间period: 100ms
elapsed = clock_systimer() - stick;
if (elapsed < period && next > 0)
{
remaining = period - elapsed;
next = MIN(next, remaining);
wqueue->worker[wndx].busy = false;
usleep(next * USEC_PER_TICK);
wqueue->worker[wndx].busy = true;
}
标签:delay,struct,FAR,work,wqueue,elapsed,nuttx,闫刚 来源: https://blog.csdn.net/yangang185/article/details/95045533