Re: [PATCH 1/2] memory: samsung: exynos5422-dmc: Adjust polling interval and uptreshold

From: Krzysztof Kozlowski
Date: Fri Jul 10 2020 - 08:45:10 EST


On Fri, Jul 10, 2020 at 09:34:45AM +0100, Lukasz Luba wrote:
> Hi Chanwoo,
>
> On 7/9/20 5:08 AM, Chanwoo Choi wrote:
> > Hi Lukasz,
> >
> > On 7/9/20 12:34 AM, Lukasz Luba wrote:
> > > In order to react faster and make better decisions under some workloads,
> > > benchmarking the memory subsystem behavior, adjust the polling interval
> > > and upthreshold value used by the simple_ondemand governor.
> > >
> > > Reported-by: Willy Wolff <willy.mh.wolff.ml@xxxxxxxxx>
> > > Signed-off-by: Lukasz Luba <lukasz.luba@xxxxxxx>
> > > ---
> > > drivers/memory/samsung/exynos5422-dmc.c | 4 ++--
> > > 1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/memory/samsung/exynos5422-dmc.c b/drivers/memory/samsung/exynos5422-dmc.c
> > > index 93e9c2429c0d..e03ee35f0ab5 100644
> > > --- a/drivers/memory/samsung/exynos5422-dmc.c
> > > +++ b/drivers/memory/samsung/exynos5422-dmc.c
> > > @@ -1466,10 +1466,10 @@ static int exynos5_dmc_probe(struct platform_device *pdev)
> > > * Setup default thresholds for the devfreq governor.
> > > * The values are chosen based on experiments.
> > > */
> > > - dmc->gov_data.upthreshold = 30;
> > > + dmc->gov_data.upthreshold = 10;
> > > dmc->gov_data.downdifferential = 5;
> > > - exynos5_dmc_df_profile.polling_ms = 500;
> > > + exynos5_dmc_df_profile.polling_ms = 100;
> > > }
> > >
> >
> > Reviewed-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> >
>
> Thank you for the review. Do you think this patch could go through
> your tree together with your patches?
>
> I don't know Krzysztof's opinion about the patch 2/2, but
> I would expect, assuming the patch itself is correct, he would
> like to take it into his next/dt branch.

In the cover letter you mentioned that this is a follow up for the
Chanwoo's patchset. But are these patches really depending on it? Can
they be picked up independently?

The DTS patch must go through arm soc, so I will take it. If it really
depends on driver changes, then it has to wait for next release.

Best regards,
Krzysztof