Re: [PATCH v4] workqueue: Warn when work flush own workqueue

[Tejun Heo]

On Thu, Aug 27, 2020 at 02:09:11PM +0800, Qianli Zhao wrote:
> @@ -2594,13 +2595,17 @@ static void check_flush_dependency(struct workqueue_struct *target_wq,
>  				   struct work_struct *target_work)
>  {
>  	work_func_t target_func = target_work ? target_work->func : NULL;
> -	struct worker *worker;
> +	struct worker *worker = current_wq_worker();
> +
> +	WARN_ONCE(worker && worker->current_pwq->wq == target_wq &&
> +		  worker->task == current &&
> +		  (target_work ? worker->current_work == target_work : true),
> +		  "workqueue: current work function:%ps is flushing own workqueue:%s",
> +		  worker->current_func, target_wq->name);

So, the idea is that we catch these with lockdeps. Doesn't lockdep trigger
for the same condition?

Thanks.

-- 
tejun