Re: [PATCH 4/4] nvme: add support for mq_ops->queue_rqs()

[Christoph Hellwig <hch@infradead.org>]

On Thu, Dec 16, 2021 at 08:45:46AM -0700, Jens Axboe wrote:
> On 12/16/21 2:08 AM, Christoph Hellwig wrote:
> > On Wed, Dec 15, 2021 at 09:24:21AM -0700, Jens Axboe wrote:
> >> +	spin_lock(&nvmeq->sq_lock);
> >> +	while (!rq_list_empty(*rqlist)) {
> >> +		struct request *req = rq_list_pop(rqlist);
> >> +		struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
> >> +
> >> +		memcpy(nvmeq->sq_cmds + (nvmeq->sq_tail << nvmeq->sqes),
> >> +				absolute_pointer(&iod->cmd), sizeof(iod->cmd));
> >> +		if (++nvmeq->sq_tail == nvmeq->q_depth)
> >> +			nvmeq->sq_tail = 0;
> > 
> > So this doesn't even use the new helper added in patch 2?  I think this
> > should call nvme_sq_copy_cmd().
> 
> But you NAK'ed that one? It definitely should use that helper, so I take it
> you are fine with it then if we do it here too? That would make 3 call sites,
> and I still do think the helper makes sense...

I explained two times that the new helpers is fine as long as you open
code nvme_submit_cmd in its two callers as it now is a trivial wrapper.