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References: <20230530024120.17196-1-powen.kao@mediatek.com>
In-Reply-To: <20230530024120.17196-1-powen.kao@mediatek.com>
From:   Stanley Chu <chu.stanley@gmail.com>
Date:   Tue, 30 May 2023 10:49:35 +0800
Message-ID: <CAGaU9a85dmzuvozHMWj4n93gfwt4Xj1qoYi2oyY_3Tcc+bFg7g@mail.gmail.com>
Subject: Re: [PATCH v1 1/1] nvme: complete directly for hctx with only one ctx mapping
To:     Po-Wen Kao <powen.kao@mediatek.com>
Cc:     linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, Jens Axboe <axboe@kernel.dk>,
        Keith Busch <kbusch@kernel.org>,
        Christoph Hellwig <hch@lst.de>,
        Sagi Grimberg <sagi@grimberg.me>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        wsd_upstream@mediatek.com, peter.wang@mediatek.com,
        stanley.chu@mediatek.com, alice.chao@mediatek.com,
        naomi.chu@mediatek.com, chun-hung.wu@mediatek.com,
        cc.chou@mediatek.com, eddie.huang@mediatek.com,
        Ed Tsai <ed.tsai@mediatek.com>, linux-block@vger.kernel.org,
        linux-nvme@lists.infradead.org
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On Tue, May 30, 2023 at 10:45=E2=80=AFAM Po-Wen Kao <powen.kao@mediatek.com=
> wrote:
>
> From: Ed Tsai <ed.tsai@mediatek.com>
>
> Refer to
> commit f168420c62e7
> ("blk-mq: don't redirect completion for hctx withs only one ctx mapping")
> When nvme applies a 1:1 mapping of hctx and ctx, there will be no remote
> request.
>
> But for ufs, the submission and completion queue could be asymmetric.
> (e.g. Multiple SQs share one CQ) Therefore, 1:1 mapping of hctx and
> ctx won't complete request on the submission cpu. In this situation,
> put this condition in block layer could violate the
> QUEUE_FLAG_SAME_FORCE, as a result, move this back to nvme.
>
> Signed-off-by: Ed Tsai <ed.tsai@mediatek.com>
> Signed-off-by: Po-Wen Kao <powen.kao@mediatek.com>

Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>