| Message ID | 3284691.aeNJFYEL58@kreacher (mailing list archive) |
|---|---|
| State | In Next |
| Delegated to: | Rafael Wysocki |
| Headers | show |
| Series | thermal: More separation between the core and drivers | expand |
On 4/2/24 19:59, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Make the comments regarding trip crossing and threshold updates in > handle_thermal_trip() slightly more clear. > > No functional impact. > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > > v2 -> v3: New patch > > --- > drivers/thermal/thermal_core.c | 26 +++++++++++++------------- > 1 file changed, 13 insertions(+), 13 deletions(-) > > Index: linux-pm/drivers/thermal/thermal_core.c > =================================================================== > --- linux-pm.orig/drivers/thermal/thermal_core.c > +++ linux-pm/drivers/thermal/thermal_core.c > @@ -368,6 +368,13 @@ static void handle_thermal_trip(struct t > if (trip->temperature == THERMAL_TEMP_INVALID) > return; > > + /* > + * If the trip temperature or hysteresis has been updated recently, > + * the threshold needs to be computed again using the new values. > + * However, its initial value still reflects the old ones and that > + * is what needs to be compared with the previous zone temperature > + * to decide which action to take. > + */ > if (tz->last_temperature == THERMAL_TEMP_INVALID) { > /* Initialization. */ > td->threshold = trip->temperature; > @@ -375,11 +382,9 @@ static void handle_thermal_trip(struct t > td->threshold -= trip->hysteresis; > } else if (tz->last_temperature < td->threshold) { > /* > - * The trip threshold is equal to the trip temperature, unless > - * the latter has changed in the meantime. In either case, > - * the trip is crossed if the current zone temperature is at > - * least equal to its temperature, but otherwise ensure that > - * the threshold and the trip temperature will be equal. > + * There is no mitigation under way, so it needs to be started > + * if the zone temperature exceeds the trip one. The new > + * threshold is then set to the low temperature of the trip. > */ > if (tz->temperature >= trip->temperature) { > thermal_notify_tz_trip_up(tz, trip); > @@ -390,14 +395,9 @@ static void handle_thermal_trip(struct t > } > } else { > /* > - * The previous zone temperature was above or equal to the trip > - * threshold, which would be equal to the "low temperature" of > - * the trip (its temperature minus its hysteresis), unless the > - * trip temperature or hysteresis had changed. In either case, > - * the trip is crossed if the current zone temperature is below > - * the low temperature of the trip, but otherwise ensure that > - * the trip threshold will be equal to the low temperature of > - * the trip. > + * Mitigation is under way, so it needs to stop if the zone > + * temperature falls below the low temperature of the trip. > + * In that case, the trip temperature becomes the new threshold. > */ > if (tz->temperature < trip->temperature - trip->hysteresis) { > thermal_notify_tz_trip_down(tz, trip); > > > Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
On 02/04/2024 20:59, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Make the comments regarding trip crossing and threshold updates in > handle_thermal_trip() slightly more clear. > > No functional impact. > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Index: linux-pm/drivers/thermal/thermal_core.c =================================================================== --- linux-pm.orig/drivers/thermal/thermal_core.c +++ linux-pm/drivers/thermal/thermal_core.c @@ -368,6 +368,13 @@ static void handle_thermal_trip(struct t if (trip->temperature == THERMAL_TEMP_INVALID) return; + /* + * If the trip temperature or hysteresis has been updated recently, + * the threshold needs to be computed again using the new values. + * However, its initial value still reflects the old ones and that + * is what needs to be compared with the previous zone temperature + * to decide which action to take. + */ if (tz->last_temperature == THERMAL_TEMP_INVALID) { /* Initialization. */ td->threshold = trip->temperature; @@ -375,11 +382,9 @@ static void handle_thermal_trip(struct t td->threshold -= trip->hysteresis; } else if (tz->last_temperature < td->threshold) { /* - * The trip threshold is equal to the trip temperature, unless - * the latter has changed in the meantime. In either case, - * the trip is crossed if the current zone temperature is at - * least equal to its temperature, but otherwise ensure that - * the threshold and the trip temperature will be equal. + * There is no mitigation under way, so it needs to be started + * if the zone temperature exceeds the trip one. The new + * threshold is then set to the low temperature of the trip. */ if (tz->temperature >= trip->temperature) { thermal_notify_tz_trip_up(tz, trip); @@ -390,14 +395,9 @@ static void handle_thermal_trip(struct t } } else { /* - * The previous zone temperature was above or equal to the trip - * threshold, which would be equal to the "low temperature" of - * the trip (its temperature minus its hysteresis), unless the - * trip temperature or hysteresis had changed. In either case, - * the trip is crossed if the current zone temperature is below - * the low temperature of the trip, but otherwise ensure that - * the trip threshold will be equal to the low temperature of - * the trip. + * Mitigation is under way, so it needs to stop if the zone + * temperature falls below the low temperature of the trip. + * In that case, the trip temperature becomes the new threshold. */ if (tz->temperature < trip->temperature - trip->hysteresis) { thermal_notify_tz_trip_down(tz, trip);