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Date: Sat, 18 May 2024 08:52:54 +0800
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Subject: Re: [PATCH stable] block/mq-deadline: fix different priority request
 on the same zone
To: Bart Van Assche <bvanassche@acm.org>, Wu Bo <bo.wu@vivo.com>
Cc: axboe@kernel.dk, dlemoal@kernel.org, linux-block@vger.kernel.org,
 linux-kernel@vger.kernel.org, stable@vger.kernel.org
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 <20240517014456.1919588-1-bo.wu@vivo.com>
 <a1da2c7e-1b29-49cf-a45f-255d3b8b0da2@acm.org>
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From: Wu Bo <wubo.oduw@gmail.com>
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On 2024/5/18 01:53, Bart Van Assche wrote:
> On 5/16/24 18:44, Wu Bo wrote:
>> So I figured this solution to fix this priority issue on zoned 
>> device. It sure
>> raises the overhead but can do fix it.
>
> Something I should have realized earlier is that this patch is not
> necessary with the latest upstream kernel (v6.10-rc1). Damien's zoned
> write plugging patch series has been merged. Hence, I/O schedulers,
> including the mq-deadline I/O schedulers, will only see a single
> zoned write at a time per zone. So it is no longer possible that
> zoned writes are reordered by the I/O scheduler because of their I/O
> priorities.
Hi Bart,

Yes, I noticed that 'zone write plugging' has been merged to latest
branch. But it seems hard to backport to old version which mq-deadline
priority feature has been merged. So is it possible to apply this fix to
old versions?

Thanks,
Wu Bo
>
> Thanks,
>
> Bart.