Re: [PATCH liburing 1/1] test: add epoll test case

[Jens Axboe]

On 1/27/20 9:17 AM, Stefano Garzarella wrote:
> Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>

You're not reaping CQ events, and hence you overflow the ring. Once
overflown, an attempt to submit new IO will returns in a -16/-EBUSY
return value. This is io_uring telling you that it won't submit more
IO until you've emptied the completion ring so io_uring can flush
the overflown entries to the ring.

-- 
Jens Axboe