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Date:   Thu, 23 Jan 2020 22:45:33 +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 23, 2020 at 12:13:57PM -0700, Jens Axboe wrote:
> On 1/16/20 10:03 AM, Stefano Garzarella wrote:
> > 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!
> 
> Gentle ping on the test case :-)
> 

Yes, you are right :-)

I was a little busy this week to finish some works before DevConf.
I hope to work on the test case these days, so by Monday I hope I have it ;-)

Cheers,
Stefano