Re: [PATCH v1 3/5] scsi: ufs: customize flush threshold for WriteBooster

[Stanley Chu]

Hi Asutosh,

Thanks for your review.

On Fri, 2020-05-08 at 11:12 -0700, Asutosh Das (asd) wrote:
> On 5/8/2020 10:15 AM, Stanley Chu wrote:
> > Allow flush threshold for WriteBooster to be customizable by
> > vendors. To achieve this, make the value as a variable in struct
> > ufs_hba first.
> > 
> > Signed-off-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
> > ---
> >   drivers/scsi/ufs/ufshcd.c | 6 ++++--
> >   drivers/scsi/ufs/ufshcd.h | 1 +
> >   2 files changed, 5 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> > index cdacbe6378a1..9a0ce6550c2f 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -5301,8 +5301,8 @@ static bool ufshcd_wb_presrv_usrspc_keep_vcc_on(struct ufs_hba *hba,
> >   			 cur_buf);
> >   		return false;
> >   	}
> > -	/* Let it continue to flush when >60% full */
> > -	if (avail_buf < UFS_WB_40_PERCENT_BUF_REMAIN)
> > +	/* Let it continue to flush when available buffer exceeds threshold */
> > +	if (avail_buf < hba->vps->wb_flush_threshold)
> >   		return true;
> >   
> >   	return false;
> > @@ -6839,6 +6839,7 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
> >   		if (!d_lu_wb_buf_alloc)
> >   			goto wb_disabled;
> >   	}
> > +
> Is this newline needed?

Oops, I will remove this in next version.
> 
> >   	return;
> >   
> >   wb_disabled:
> > @@ -7462,6 +7463,7 @@ static const struct attribute_group *ufshcd_driver_groups[] = {
> >   
> >   static struct ufs_hba_variant_params ufs_hba_vps = {
> >   	.hba_enable_delay_us		= 1000,
> > +	.wb_flush_threshold		= UFS_WB_40_PERCENT_BUF_REMAIN,
> >   	.devfreq_profile.polling_ms	= 100,
> >   	.devfreq_profile.target		= ufshcd_devfreq_target,
> >   	.devfreq_profile.get_dev_status	= ufshcd_devfreq_get_dev_status,
> > diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> > index f7bdf52ba8b0..e3dfb48e669e 100644
> > --- a/drivers/scsi/ufs/ufshcd.h
> > +++ b/drivers/scsi/ufs/ufshcd.h
> > @@ -570,6 +570,7 @@ struct ufs_hba_variant_params {
> >   	struct devfreq_dev_profile devfreq_profile;
> >   	struct devfreq_simple_ondemand_data ondemand_data;
> >   	u16 hba_enable_delay_us;
> > +	u32 wb_flush_threshold;
> >   };
> >   
> >   /**
> > 
> 
> Patch[3] & [4] may be combined into a single patch perhaps?
> Patch[4] just redoes what [3] did in a different way, so might as well 
> just do what patch[4] does right away.

OK! I will try to merge both to a single patch in next version.
Let me know if you have any other comments for the whole series.

Thanks,
Stanley Chu

> 
>