Re: [PATCH -next v3 1/3] block, bfq: record how many queues are busy in bfq_group

[yukuai (C)]

在 2022/04/27 20:52, Jan Kara 写道:
> On Wed 27-04-22 20:47:20, Yu Kuai wrote:
> > Prepare to refactor the counting of 'num_groups_with_pending_reqs'.
> >
> > Add a counter 'busy_queues' in bfq_group, and update it in
> > bfq_add/del_bfqq_busy().
> >
> > Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
>
> ...
>
> > diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c
> > index f8eb340381cf..53826797430f 100644
> > --- a/block/bfq-wf2q.c
> > +++ b/block/bfq-wf2q.c
> > @@ -218,6 +218,14 @@ static bool bfq_no_longer_next_in_service(struct bfq_entity *entity)
> >   	return false;
> >   }
> >   
> > +static void bfq_update_busy_queues(struct bfq_queue *bfqq, bool is_add)
> > +{
> > +	if (is_add)
> > +		bfqq_group(bfqq)->busy_queues++;
> > +	else
> > +		bfqq_group(bfqq)->busy_queues--;
> > +}
> > +
> >   #else /* CONFIG_BFQ_GROUP_IOSCHED */
>
> I think the bool argument here unnecessarily hurts readability (it's
> difficult to see what the argument means without looking into the
> implementation). I'd rather create two functions bfq_{inc,dec}_busy_queues()
> or if you really insist on a single function, we can have
> bfq_add_busy_queues() and have 'int' argument that will be +1 or -1.

Thanks for the suggestion, I'll create two functions in next iteration.
> 								Honza