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Date:   Thu, 16 Jan 2020 18:03:42 +0100
From:   Stefano Garzarella <sgarzare@redhat.com>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>, io-uring@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] io_uring: wakeup threads waiting for EPOLLOUT events
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On Thu, Jan 16, 2020 at 09:30:12AM -0700, Jens Axboe wrote:
> On 1/16/20 9:26 AM, Stefano Garzarella wrote:
> >> Since the use case is mostly single submitter, unless you're doing
> >> something funky or unusual, you're not going to be needing POLLOUT ever.
> > 
> > The case that I had in mind was with kernel side polling enabled and
> > a single submitter that can use epoll() to wait free slots in the SQ
> > ring. (I don't have a test, maybe I can write one...)
> 
> Right, I think that's the only use case where it makes sense, because
> you have someone else draining the sq side for you. A test case would
> indeed be nice, liburing has a good arsenal of test cases and this would
> be a good addition!

Sure, I'll send a test to liburing for this case!

Thanks,
Stefano