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Date:   Thu, 13 Aug 2020 17:47:57 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Mike Snitzer <snitzer@redhat.com>
Cc:     Christoph Hellwig <hch@lst.de>, Chao Leng <lengchao@huawei.com>,
        axboe@fb.com, sagi@grimberg.me, linux-nvme@lists.infradead.org,
        linux-block@vger.kernel.org, kbusch@kernel.org
Subject: Re: [PATCH 2/3] nvme-core: delete the dependency on blk status
Message-ID: <20200813154757.GA14486@lst.de>
References: <20200812081844.22224-1-lengchao@huawei.com> <20200812151035.GB29544@lst.de> <20200812202829.GA586@redhat.com>
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On Wed, Aug 12, 2020 at 04:28:30PM -0400, Mike Snitzer wrote:
> On Wed, Aug 12 2020 at 11:10am -0400,
> Christoph Hellwig <hch@lst.de> wrote:
> 
> > On Wed, Aug 12, 2020 at 04:18:44PM +0800, Chao Leng wrote:
> > > nvme should not depend on blk status, just need check nvme status.
> > > Just need do translating nvme status to blk status for returning error.
> > 
> > While this doesn't look wrong it also doesn't save us a single
> > instruction and actually adds more lines of code.  Do you have a good
> > reason for this change?
> 
> It certainly saves nvme_error_status(nvme_req(req)->status if
> nvme_req_needs_retry().

Yeah, but the retry path isn't exactly the fast path, is it?

Not that I really care too much about this one..