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Message-ID: <d0e823d9-292d-932c-9849-1d4d08c9f4eb@bytedance.com>
Date:   Tue, 11 Jul 2023 19:15:43 +0800
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Subject: Re: [External] Re: [PATCH 1/2] blk-flush: fix rq->flush.seq for
 post-flush requests
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To:     Christoph Hellwig <hch@lst.de>
Cc:     axboe@kernel.dk, ming.lei@redhat.com, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Chengming Zhou <chengming.zhou@linux.dev>
References: <20230710064705.1847287-1-chengming.zhou@linux.dev>
 <20230710133024.GA23157@lst.de>
 <4431d779-e6e7-aff1-5cf8-4147de974d8d@linux.dev>
From:   Chengming Zhou <zhouchengming@bytedance.com>
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On 2023/7/11 19:06, Chengming Zhou wrote:
> On 2023/7/10 21:30, Christoph Hellwig wrote:
>> On Mon, Jul 10, 2023 at 02:47:04PM +0800, chengming.zhou@linux.dev wrote:
>>> From: Chengming Zhou <zhouchengming@bytedance.com>
>>>
>>> If the policy == (REQ_FSEQ_DATA | REQ_FSEQ_POSTFLUSH), it means that the
>>> data sequence and post-flush sequence need to be done for this request.
>>>
>>> The rq->flush.seq should record what sequences have been done (or don't
>>> need to be done). So in this case, pre-flush doesn't need to be done,
>>> we should init rq->flush.seq to REQ_FSEQ_PREFLUSH not REQ_FSEQ_POSTFLUSH.
>>>
>>> Of course, this doesn't cause any problem in fact, since pre-flush and
>>> post-flush sequence do the same thing for now.
>>
>> I wonder if it really doesn't cause any problems, but the change for
>> sure looks good:
>>
>> Reviewed-by: Christoph Hellwig <hch@lst.de>
>>
>> It should probably go before your other flush optimizations and maybe
>> grow a fixes tag.
> 
> Ok, will add a Fixes tag and send it as a separate patch since it's a bug fix.
> 

Well, I should put it in that series before other flush optimizations instead.