Re: Re: [PATCH 4/4] blk-mq: improve readability of blk_mq_alloc_request()

From: Jinlong Chen
Date: Tue Nov 01 2022 - 22:39:32 EST





> -----原始邮件-----
> 发件人: "Jens Axboe" <axboe@xxxxxxxxx>
> 发送时间: 2022-11-02 10:25:27 (星期三)
> 收件人: "Jinlong Chen" <nickyc975@xxxxxxxxxx>, "Christoph Hellwig" <hch@xxxxxx>
> 抄送: linux-block@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx
> 主题: Re: [PATCH 4/4] blk-mq: improve readability of blk_mq_alloc_request()
>
> On 11/1/22 8:19 PM, Jinlong Chen wrote:
> >> On Tue, Nov 01, 2022 at 11:11:37PM +0800, Jinlong Chen wrote:
> >>> Add a helper blk_mq_alloc_request_nocache() to alloc request without
> >>> cache. This makes blk_mq_alloc_request() more readable.
> >>>
> >>> Signed-off-by: Jinlong Chen <nickyc975@xxxxxxxxxx>
> >>> ---
> >>> block/blk-mq.c | 47 +++++++++++++++++++++++++++++------------------
> >>> 1 file changed, 29 insertions(+), 18 deletions(-)
> >>>
> >>> diff --git a/block/blk-mq.c b/block/blk-mq.c
> >>> index 87a6348a0d0a..2fae111a42c8 100644
> >>> --- a/block/blk-mq.c
> >>> +++ b/block/blk-mq.c
> >>> @@ -572,36 +572,47 @@ static struct request *blk_mq_alloc_cached_request(struct request_queue *q,
> >>> return rq;
> >>> }
> >>>
> >>> +static struct request *blk_mq_alloc_request_nocache(struct request_queue *q,
> >>> + blk_opf_t opf, blk_mq_req_flags_t flags)
> >>
> >> The name is a bit odd, but I can't think off a better one.
> >>
> >>> + struct blk_mq_alloc_data data = {
> >>> .q = q,
> >>> .flags = flags,
> >>> .cmd_flags = opf,
> >>> .nr_tags = 1,
> >>> };
> >>
> >> And this now has superflous indenation. Overall, while the separate
> >> helper looks marginally nicer, I'm not really sure it is worth the
> >> churn.
> >
> > I'll drop the patch if you think it is not worth the churn. But I
> > started doing this because of the following goto statement:
>
> Please just drop it, I don't think it's an improvement.

Ok, then I'll just resend patch 2 without the silly goto return NULL and
patch 3.

Thanks!
Jinlong Chen