Re: [PATCH 1/2] scsi: ufs: Protect some contexts from unexpected clock scaling

[Can Guo]

On 2020-12-11 09:36, Can Guo wrote:
> On 2020-12-11 01:34, Bean Huo wrote:
> > Hi Can
> >
> > On Wed, 2020-12-09 at 05:35 -0800, Can Guo wrote:
> > > @@ -1160,6 +1166,7 @@ static void
> > > ufshcd_clock_scaling_unprepare(struct ufs_hba *hba)
> > >  {
> > >  	up_write(&hba->clk_scaling_lock);
> > >  	ufshcd_scsi_unblock_requests(hba);
> > > +	ufshcd_release(hba);
> > >  }
> > >
> > >  /**
> > > @@ -1175,12 +1182,9 @@ static int ufshcd_devfreq_scale(struct ufs_hba
> > > *hba, bool scale_up)
> > >  {
> > >  	int ret = 0;
> > >
> > > -	/* let's not get into low power until clock scaling is
> > > completed */
> > > -	ufshcd_hold(hba, false);
> > > -
> > >  	ret = ufshcd_clock_scaling_prepare(hba);
> > >  	if (ret)
> > > -		goto out;
> > > +		return ret;
> > >
> > >  	/* scale down the gear before scaling down clocks */
> > >  	if (!scale_up) {
> > > @@ -1212,8 +1216,6 @@ static int ufshcd_devfreq_scale(struct ufs_hba
> > > *hba, bool scale_up)
> > >
> > >  out_unprepare:
> > >  	ufshcd_clock_scaling_unprepare(hba);
> > > -out:
> > > -	ufshcd_release(hba);
> > >  	return ret;
> > >  }
> >
> > I didn't understand why moving ufshcd_hold/ufshcd_release into
> > ufshcd_clock_scaling_prepare()/ufshcd_clock_scaling_unprepare().
> >
> >
> > > @@ -1294,15 +1296,8 @@ static int ufshcd_devfreq_target(struct device
> > > *dev,
> > >  	}
> > >  	spin_unlock_irqrestore(hba->host->host_lock, irq_flags);
> > >
> > > -	pm_runtime_get_noresume(hba->dev);
> > > -	if (!pm_runtime_active(hba->dev)) {
> > > -		pm_runtime_put_noidle(hba->dev);
> > > -		ret = -EAGAIN;
> > > -		goto out;
> > > -	}
> > >  	start = ktime_get();
> > >  	ret = ufshcd_devfreq_scale(hba, scale_up);
> > > -	pm_runtime_put(hba->dev);
> >
> > which branch are you working on?  I didn't see this part codes in the
> > branch 5.11/scsi-queue and 5.11/scsi-staging.
> >
> > Bean
>
> As I mentioned in my cover-letter, this is based on 5.11/scsi-fixes.
> These codes came from one of my earlier changes, but since this change
> can cover the old change's functionality, so I removed the codes.
>
> Can Guo.

Hi Bean,

Sorry for the typo, it is branch 5.10/scsi-fixes.

Thanks,

Can Guo.