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Date:   Thu, 22 Sep 2022 08:20:10 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Liu Song <liusong@linux.alibaba.com>
Cc:     axboe@kernel.dk, hch@lst.de, kbusch@kernel.org,
        linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
        sagi@grimberg.me
Subject: Re: [RFC PATCH] blk-mq: hctx has only one ctx mapping is no need
 to redirect the completion
Message-ID: <20220922062010.GA27946@lst.de>
References: <894e18a4-4504-df48-6429-a04c222ca064@kernel.dk> <1663731123-81536-1-git-send-email-liusong@linux.alibaba.com>
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On Wed, Sep 21, 2022 at 11:32:03AM +0800, Liu Song wrote:
> From: Liu Song <liusong@linux.alibaba.com>
> 
> High-performance NVMe devices usually support a large hw queue, which

a larger number of?

>  	/*
> -	 * For a polled request, always complete locally, it's pointless
> -	 * to redirect the completion.
> +	 * For request which hctx has only one ctx mapping,
> +	 * or a polled request, always complete locally,
> +	 * it's pointless to redirect the completion.
>  	 */
> -	if (rq->cmd_flags & REQ_POLLED)
> +	if (rq->mq_hctx->nr_ctx == 1 ||
> +		rq->cmd_flags & REQ_POLLED)

Some very odd comment formatting and and indentation here.