RE: RE: [PATCH v4 7/9] scsi: ufshpb: Add "Cold" regions timer

From: Daejun Park
Date: Tue Mar 02 2021 - 04:49:54 EST


Hi Avri,
> >
> > Hi Avri,
> >
> > > +static void ufshpb_read_to_handler(struct work_struct *work)
> > > +{
> > > + struct delayed_work *dwork = to_delayed_work(work);
> > > + struct ufshpb_lu *hpb;
> > > + struct victim_select_info *lru_info;
> > > + struct ufshpb_region *rgn;
> > > + unsigned long flags;
> > > + LIST_HEAD(expired_list);
> > > +
> > > + hpb = container_of(dwork, struct ufshpb_lu, ufshpb_read_to_work);
> > > +
> > > + if (test_and_set_bit(TIMEOUT_WORK_PENDING, &hpb-
> > >work_data_bits))
> > > + return;
> > > +
> > > + spin_lock_irqsave(&hpb->rgn_state_lock, flags);
> > > +
> > > + lru_info = &hpb->lru_info;
> > > +
> > > + list_for_each_entry(rgn, &lru_info->lh_lru_rgn, list_lru_rgn) {
> > > + bool timedout = ktime_after(ktime_get(), rgn->read_timeout);
> > > +
> > > + if (timedout) {
> >
> > It is important not just to check the timeout, but how much time has passed.
> > If the time exceeded is twice the threshold, the read_timeout_expiries
> > value should be reduced by 2 instead of 1.
> Theoretically this shouldn't happened.
> Please note that POLLING_INTERVAL_MS << READ_TO_MS.
> Better add appropriate check when making those configurable.

OK, I agree.

Thanks,
Daejun

>
> Thanks,
> Avri
> >
> > > + rgn->read_timeout_expiries--;
> >
> > Thanks,
> > Daejun
>
>
>
>