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Date:   Wed, 29 Dec 2021 12:59:45 -0800
From:   Keith Busch <kbusch@kernel.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     linux-nvme@lists.infradead.org, linux-block@vger.kernel.org,
        axboe@kernel.dk, sagi@grimberg.me
Subject: Re: [PATCHv2 2/3] block: introduce rq_list_move
Message-ID: <20211229205945.GB2493133@dhcp-10-100-145-180.wdc.com>
References: <20211227164138.2488066-1-kbusch@kernel.org>
 <20211227164138.2488066-2-kbusch@kernel.org>
 <20211229174109.GB28058@lst.de>
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On Wed, Dec 29, 2021 at 06:41:09PM +0100, Christoph Hellwig wrote:
> On Mon, Dec 27, 2021 at 08:41:37AM -0800, Keith Busch wrote:
> > +/**
> > + * rq_list_move() - move a struct request from one list to another
> > + * @src: The source list @rq is currently in
> > + * @dst: The destination list that @rq will be appended to
> > + * @rq: The request to move
> > + * @prv: The request preceding @rq in @src (NULL if @rq is the head)
> > + * @nxt: The request following @rq in @src (NULL if @rq is the tail)
> > + */
> > +static void inline rq_list_move(struct request **src, struct request **dst,
> > +				struct request *rq, struct request *prv,
> > +				struct request *nxt)
> > +{
> > +	if (prv)
> > +		prv->rq_next = nxt;
> > +	else
> > +		*src = nxt;
> > +	rq_list_add(dst, rq);
> > +}
> 
> Do we even need the nxt argument?  I think it should always be
> rq->rq_next?

Sure. I only used it here because the safe iterator already has rq_next.
It's not an optimization, so I'll remove it.