Re: [PATCH v3] thermal/core: Clear all mitigation when thermal zone is disabled

[Manaf Meethalavalappu Pallikunhi]

HI Daniel,

On 1/24/2022 6:35 AM, Pandruvada, Srinivas wrote:
> On Sun, 2022-01-23 at 21:51 +0100, Daniel Lezcano wrote:
> > Hi Manaf,
> >
> > semantically speaking disabling a thermal zone would be to detach the
> > thermal zone from its governor and stop the monitoring.
> >
> > May be add the functions
> >
> >   - thermal_governor_attach(struct thermal_zone_device *tzd)
> >     {
> >          ...
> >          if (tz->governor && tz->governor->bind_to_tz) {
> >                  if (tz->governor->bind_to_tz(tz)) {
> >          }
> >          ...
> >     }
> >
> >   - thermal_governor_detach(struct thermal_zone_device *tzd)
> >     {
> >          ...
> >          if (tz->governor && tz->governor->unbind_from_tz)
> >                  tz->governor->unbind_from_tz(tz);
> >          ...
> >     }
> >
> > And add in the step_wise and power_allocator the reset of the
> > governor's
> > data as well as the cooling device instances in the unbind_from_tz()
> > callback
> >
> > Then, thermal_zone_device_enable() attaches and
> > thermal_zone_device_disable() detaches the governor.
> >
> > Does it make sense ?
> This is better.
>
> Thanks,
> Srinivas
Yes, it makes sense. I will update it in v4
> > On 07/01/2022 19:56, Manaf Meethalavalappu Pallikunhi wrote:
> > > Whenever a thermal zone is in trip violated state, there is a
> > > chance
> > > that the same thermal zone mode can be disabled either via thermal
> > > core API or via thermal zone sysfs. Once it is disabled, the
> > > framework
> > > bails out any re-evaluation of thermal zone. It leads to a case
> > > where
> > > if it is already in mitigation state, it will stay the same state
> > > until it is re-enabled.
> > >
> > > To avoid above mentioned issue, on thermal zone disable request
> > > reset thermal zone and clear mitigation for each trip explicitly.
> > >
> > > Signed-off-by: Manaf Meethalavalappu Pallikunhi
> > > <quic_manafm@xxxxxxxxxxx>
> > > ---
> > >   drivers/thermal/thermal_core.c | 12 ++++++++++--
> > >   1 file changed, 10 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/thermal/thermal_core.c
> > > b/drivers/thermal/thermal_core.c
> > > index 51374f4..e288c82 100644
> > > --- a/drivers/thermal/thermal_core.c
> > > +++ b/drivers/thermal/thermal_core.c
> > > @@ -447,10 +447,18 @@ static int
> > > thermal_zone_device_set_mode(struct thermal_zone_device *tz,
> > >   
> > >          thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
> > >   
> > > -       if (mode == THERMAL_DEVICE_ENABLED)
> > > +       if (mode == THERMAL_DEVICE_ENABLED) {
> > >                  thermal_notify_tz_enable(tz->id);
> > > -       else
> > > +       } else {
> > > +               int trip;
> > > +
> > > +               /* make sure all previous throttlings are cleared
> > > */
> > > +               thermal_zone_device_init(tz);
> > > +               for (trip = 0; trip < tz->trips; trip++)
> > > +                       handle_thermal_trip(tz, trip);
> > > +
> > >                  thermal_notify_tz_disable(tz->id);
> > > +       }
> > >   
> > >          return ret;
> > >   }