Re: [RFC] io_uring: print COMM on ctx_exit hang

[Jens Axboe <axboe@kernel.dk>]

On 10/6/21 9:15 AM, Pavel Begunkov wrote:
> io_ring_exit_work() hangs are hard to debug partly because there is not
> much information of who created the ctx by the time it's exiting, and
> the function is running in a wq context, so the task name tells us
> nothing. Save creator's task comm and print it when it hangs.
> 
> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
> ---
> 
> Just for discussion, I hope there are better ways of doing it.
> 
> It leaves out the second wait_for_completion() in io_ring_exit_work(),
> which is of interest, so would be great to cover the case as well.

I've done identical patches in the past myself, and I don't think
there's a better way to do this. The task may be long gone, so we have
to capture it upfront.

-- 
Jens Axboe