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Date:   Mon, 24 Jul 2023 12:22:07 -0600
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Subject: Re: [PATCH] io_uring: Use io_schedule* in cqring wait
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To:     Phil Elwell <phil@raspberrypi.com>
Cc:     Greg KH <gregkh@linuxfoundation.org>, andres@anarazel.de,
        asml.silence@gmail.com, david@fromorbit.com, hch@lst.de,
        io-uring@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
        linux-xfs@vger.kernel.org, stable <stable@vger.kernel.org>
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From:   Jens Axboe <axboe@kernel.dk>
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On 7/24/23 10:48 AM, Phil Elwell wrote:
> Hi Jens,
> 
> On Mon, 24 Jul 2023 at 17:08, Jens Axboe <axboe@kernel.dk> wrote:
>>
>> On 7/24/23 10:07?AM, Phil Elwell wrote:
>>>> Even though I don't think this is an actual problem, it is a bit
>>>> confusing that you get 100% iowait while waiting without having IO
>>>> pending. So I do think the suggested patch is probably worthwhile
>>>> pursuing. I'll post it and hopefully have Andres test it too, if he's
>>>> available.
>>>
>>> If you CC me I'll happily test it for you.
>>
>> Here it is.
> 
> < snip >
> 
> Thanks, that works for me on top of 6.5-rc3. Going to 6.1 is a
> non-trivial (for me) back-port - the switch from "ret = 0" in 6.5 to
> "ret = 1" in 6.1 is surprising.

Great, thanks for testing. I'll take care of the stable backports
once the patch lands in upstream -git later this week.

-- 
Jens Axboe