Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH] io_uring: wakeup threads waiting for EPOLLOUT events
To:     Stefano Garzarella <sgarzare@redhat.com>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>, io-uring@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
References: <20200116134946.184711-1-sgarzare@redhat.com>
 <2d2dda92-3c50-ee62-5ffe-0589d4c8fc0d@kernel.dk>
 <20200116155557.mwjc7vu33xespiag@steredhat>
 <5723453a-9326-e954-978e-910b8b495b38@kernel.dk>
 <20200116162630.6r3xc55kdyyq5tvz@steredhat>
 <a02a58dc-bf23-ed74-aec6-52c85360fe00@kernel.dk>
 <20200116170342.4jvkhbbw4x6z3txn@steredhat>
 <2d3d4932-8894-6969-4006-25141ca1286e@kernel.dk>
 <20200123214533.ikn4olf7k5dfbaq6@steredhat>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <3805d100-c687-e49e-9317-7cd9b387a3a7@kernel.dk>
Date:   Thu, 23 Jan 2020 18:28:06 -0700
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.4.1
MIME-Version: 1.0
In-Reply-To: <20200123214533.ikn4olf7k5dfbaq6@steredhat>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 1/23/20 2:45 PM, Stefano Garzarella wrote:
> 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 ;-)

Thanks, all good, just a gentle nudge ;-)

-- 
Jens Axboe