Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <af5df07e-f93f-9588-4fdb-b89b37aa28a1@baylibre.com>
Date:   Wed, 31 May 2023 11:40:04 +0200
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.11.0
Subject: Re: [PATCH v2] blk-mq: check on cpu id when there is only one ctx
 mapping
Content-Language: en-US
To:     Ed Tsai <ed.tsai@mediatek.com>, axboe@kernel.dk
Cc:     kbusch@kernel.org, liusong@linux.alibaba.com,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, wsd_upstream@mediatek.com,
        peter.wang@mediatek.com, stanley.chu@mediatek.com,
        powen.kao@mediatek.com, alice.chao@mediatek.com,
        naomi.chu@mediatek.com
References: <20230531083828.8009-1-ed.tsai@mediatek.com>
 <20230531083828.8009-2-ed.tsai@mediatek.com>
From:   Alexandre Mergnat <amergnat@baylibre.com>
In-Reply-To: <20230531083828.8009-2-ed.tsai@mediatek.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 31/05/2023 10:38, Ed Tsai wrote:
> commit f168420 ("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 queues 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,
> this nr_ctx check could violate the QUEUE_FLAG_SAME_FORCE, as a result,
> check on cpu id when there is only one ctx mapping.

Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>

-- 
Regards,
Alexandre