Re: [PATCH v4 0/3] Improve IPA mechanisms in low temperature state

[Lukasz Luba]

On 4/22/21 6:30 PM, Daniel Lezcano wrote:
> On 22/04/2021 13:43, Lukasz Luba wrote:
> > Hi all,
> >
> > This v4 patch set aims to address the issues present in IPA when the
> > temperature is below the first trip point and cooling devices are not
> > throttled.
> > The last patch 1/3 is co-developed by Daniel, who presented the code
> > during v2 review. I have created a helper function based on his idea,
> > which can now be used inside IPA governor lock protected code.
> > The patch 2/3 adds a basic check of cooling devices power to keep the
> > internal statistics fresh. This allows to avoid issue when the statistics
> > cover very long period, because they were not maintained.
> > The patch 3/3 addresses an issue described in bugzilla [1], which is:
> > unnecessary updating cooling devices when their state has not changed
> > because they are not throttled. This update triggers sending an event,
> > which should be avoided. Thus, patch 2/3 adds a tracking mechanism if
> > the update was triggered and makes sure it will be done only once when
> > the temperature continue to stay below first trip point.
> >
> > changelog:
> > v4:
> > - reordered the patches, patch 3/3 from v3 is now 1/3
> > v3:
> > - new patch 3/3 co-developed with Daniel
> > v2:
> > - patch 2/2 uses now simple 'update' bool flag and information from
> >    'tz->last_temperature'
> > - patch 1/2 has small change in the comment
> > - re-based on top of today's thermal/next branch
> >
> > Regards,
> > Lukasz Luba
> >
> > [1] https://bugzilla.kernel.org/show_bug.cgi?id=212501
> >
> > Lukasz Luba (3):
> >    thermal: create a helper __thermal_cdev_update() without a lock
> >    thermal: power_allocator: maintain the device statistics from going
> >      stale
> >    thermal: power_allocator: update once cooling devices when temp is low
> >
> >   drivers/thermal/gov_power_allocator.c | 21 +++++++++++++++++----
> >   drivers/thermal/thermal_core.h        |  1 +
> >   drivers/thermal/thermal_helpers.c     | 27 +++++++++++++++++----------
> >   3 files changed, 35 insertions(+), 14 deletions(-)
>
> Applied, thanks

Thank you Daniel!

Regards,
Lukasz