Re: [PATCH V5 4/7] blk-mq: introduce blk_mq_dequeue_from_ctx()

From: Ming Lei
Date: Mon Oct 09 2017 - 00:37:55 EST


On Tue, Oct 03, 2017 at 02:01:09AM -0700, Christoph Hellwig wrote:
> On Sat, Sep 30, 2017 at 06:27:17PM +0800, Ming Lei wrote:
> > This function is introduced for dequeuing request
> > from sw queue so that we can dispatch it in
> > scheduler's way.
> >
> > More importantly, some SCSI devices may set
> > q->queue_depth, which is a per-request_queue limit,
> > and applied on pending I/O from all hctxs. This
> > function is introduced for avoiding to dequeue too
> > many requests from sw queue when ->dispatch isn't
> > flushed completely.
>
> Weird commit log formatting, please use your 70+ chacters to format the
> text.

OK.

>
> > @@ -882,6 +882,44 @@ void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list)
> > }
> > EXPORT_SYMBOL_GPL(blk_mq_flush_busy_ctxs);
> >
> > +struct dispatch_rq_data {
> > + struct blk_mq_hw_ctx *hctx;
> > + struct request *rq;
> > +};
> > +
> > +static bool dispatch_rq_from_ctx(struct sbitmap *sb, unsigned int bitnr, void *data)
>
> Overly long line.
>
> But except for that this looks ok to me except for the fact that you
> just add an unused function.

OK

--
Ming