Re: [PATCH RFC v2 8/8] blk-mq-tag: allow shared queue/hctx to get more driver tags

[Yu Kuai]

Hi,

在 2023/10/24 4:46, Bart Van Assche 写道:
> On 10/21/23 08:48, Yu Kuai wrote:
> > +    if (!busy) {
> > +        ctl->timer_running = false;
> > +    } else {
> > +        ctl->timer.expires = jiffies + HZ;
> > +        add_timer(&ctl->timer);
> > +    }
> > +    spin_unlock_irq(&tags->lock);
>
> [ ... ]
>
> > +inc_busy:
> > +    atomic_inc(&info->busy_count);
> > +    if (!tags->ctl.timer_running &&
> > +        try_cmpxchg_relaxed(&tags->ctl.timer_running, &timer_running, 
> > true)) {
> > +        tags->ctl.timer.expires = jiffies + HZ;
> > +        add_timer(&tags->ctl.timer);
> > +    }
> >   }
>
> So the choice has been made to let the timer expire after one second? I
> think the choice of the timer value is important enough to mention it in
> the patch description.

Yes, I agree, I admit that I was not that cautious while choose 1 HZ in
this version, I'm not quite sure is this approch will be accepted yet,
while this is the best(simple and workable) way that I can think of.

Thanks,
Kuai

> Thanks,
>
> Bart.
>
>
> .