| Message ID | 7648070.EvYhyI6sBW@kreacher |
|---|---|
| State | New |
| Headers | show |
| Series | thermal: More separation between the core and drivers | expand |
On 4/2/24 20:03, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > If multiple trip points are crossed in one go and the trips table in > the thermal zone device object is not sorted, the corresponding trip > point crossing notifications sent to user space will not be ordered > either. > > Moreover, if the trips table is sorted by trip temperature in ascending > order, the trip crossing notifications on the way up will be sent in that > order too, but the trip crossing notifications on the way down will be > sent in the reverse order. > > This is generally confusing and it is better to make the kernel send the > notifications in the order of growing (on the way up) or falling (on the > way down) trip temperature. > > To achieve that, instead of sending a trip crossing notification and > recording a trip crossing event in the statistics right away from > handle_thermal_trip(), put the trip in question on a list that will be > sorted by __thermal_zone_device_update() after processing all of the trips > and before sending the notifications and recording trip crossing events. > > Link: https://lore.kernel.org/linux-pm/20240306085428.88011-1-daniel.lezcano@linaro.org/ > Reported-by: Daniel Lezcano <daniel.lezcano@linaro.org> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > > v2 -> v3: Rebase, update changelog, add notify_temp to struct thermal_trip_desc > > v1 -> v2: New patch > > --- > drivers/thermal/thermal_core.c | 41 +++++++++++++++++++++++++++++++++++------ > drivers/thermal/thermal_core.h | 2 ++ > 2 files changed, 37 insertions(+), 6 deletions(-) > > Index: linux-pm/drivers/thermal/thermal_core.c > =================================================================== > --- linux-pm.orig/drivers/thermal/thermal_core.c > +++ linux-pm/drivers/thermal/thermal_core.c > @@ -15,6 +15,7 @@ > #include <linux/slab.h> > #include <linux/kdev_t.h> > #include <linux/idr.h> > +#include <linux/list_sort.h> > #include <linux/thermal.h> > #include <linux/reboot.h> > #include <linux/string.h> > @@ -361,7 +362,9 @@ static void handle_critical_trips(struct > } > > static void handle_thermal_trip(struct thermal_zone_device *tz, > - struct thermal_trip_desc *td) > + struct thermal_trip_desc *td, > + struct list_head *way_up_list, > + struct list_head *way_down_list) > { > const struct thermal_trip *trip = &td->trip; > int old_threshold; > @@ -387,8 +390,8 @@ static void handle_thermal_trip(struct t > * In that case, the trip temperature becomes the new threshold. > */ > if (tz->temperature < trip->temperature - trip->hysteresis) { > - thermal_notify_tz_trip_down(tz, trip); > - thermal_debug_tz_trip_down(tz, trip); > + list_add(&td->notify_list_node, way_down_list); > + td->notify_temp = trip->temperature - trip->hysteresis; > } else { > td->threshold -= trip->hysteresis; > } > @@ -398,8 +401,8 @@ static void handle_thermal_trip(struct t > * if the zone temperature exceeds the trip one. The new > * threshold is then set to the low temperature of the trip. > */ > - thermal_notify_tz_trip_up(tz, trip); > - thermal_debug_tz_trip_up(tz, trip); > + list_add_tail(&td->notify_list_node, way_up_list); > + td->notify_temp = trip->temperature; > td->threshold -= trip->hysteresis; > } > > @@ -452,10 +455,24 @@ static void thermal_zone_device_init(str > pos->initialized = false; > } > > +static int thermal_trip_notify_cmp(void *ascending, const struct list_head *a, > + const struct list_head *b) > +{ > + struct thermal_trip_desc *tda = container_of(a, struct thermal_trip_desc, > + notify_list_node); > + struct thermal_trip_desc *tdb = container_of(b, struct thermal_trip_desc, > + notify_list_node); > + int ret = tdb->notify_temp - tda->notify_temp; > + > + return ascending ? ret : -ret; > +} > + > void __thermal_zone_device_update(struct thermal_zone_device *tz, > enum thermal_notify_event event) > { > struct thermal_trip_desc *td; > + LIST_HEAD(way_down_list); > + LIST_HEAD(way_up_list); > > if (tz->suspended) > return; > @@ -470,7 +487,19 @@ void __thermal_zone_device_update(struct > tz->notify_event = event; > > for_each_trip_desc(tz, td) > - handle_thermal_trip(tz, td); > + handle_thermal_trip(tz, td, &way_up_list, &way_down_list); > + > + list_sort(&way_up_list, &way_up_list, thermal_trip_notify_cmp); > + list_for_each_entry(td, &way_up_list, notify_list_node) { > + thermal_notify_tz_trip_up(tz, &td->trip); > + thermal_debug_tz_trip_up(tz, &td->trip); > + } > + > + list_sort(NULL, &way_down_list, thermal_trip_notify_cmp); > + list_for_each_entry(td, &way_down_list, notify_list_node) { > + thermal_notify_tz_trip_down(tz, &td->trip); > + thermal_debug_tz_trip_down(tz, &td->trip); > + } > > monitor_thermal_zone(tz); > } > Index: linux-pm/drivers/thermal/thermal_core.h > =================================================================== > --- linux-pm.orig/drivers/thermal/thermal_core.h > +++ linux-pm/drivers/thermal/thermal_core.h > @@ -17,6 +17,8 @@ > > struct thermal_trip_desc { > struct thermal_trip trip; > + struct list_head notify_list_node; > + int notify_temp; > int threshold; > }; > > > > Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Index: linux-pm/drivers/thermal/thermal_core.c =================================================================== --- linux-pm.orig/drivers/thermal/thermal_core.c +++ linux-pm/drivers/thermal/thermal_core.c @@ -15,6 +15,7 @@ #include <linux/slab.h> #include <linux/kdev_t.h> #include <linux/idr.h> +#include <linux/list_sort.h> #include <linux/thermal.h> #include <linux/reboot.h> #include <linux/string.h> @@ -361,7 +362,9 @@ static void handle_critical_trips(struct } static void handle_thermal_trip(struct thermal_zone_device *tz, - struct thermal_trip_desc *td) + struct thermal_trip_desc *td, + struct list_head *way_up_list, + struct list_head *way_down_list) { const struct thermal_trip *trip = &td->trip; int old_threshold; @@ -387,8 +390,8 @@ static void handle_thermal_trip(struct t * In that case, the trip temperature becomes the new threshold. */ if (tz->temperature < trip->temperature - trip->hysteresis) { - thermal_notify_tz_trip_down(tz, trip); - thermal_debug_tz_trip_down(tz, trip); + list_add(&td->notify_list_node, way_down_list); + td->notify_temp = trip->temperature - trip->hysteresis; } else { td->threshold -= trip->hysteresis; } @@ -398,8 +401,8 @@ static void handle_thermal_trip(struct t * if the zone temperature exceeds the trip one. The new * threshold is then set to the low temperature of the trip. */ - thermal_notify_tz_trip_up(tz, trip); - thermal_debug_tz_trip_up(tz, trip); + list_add_tail(&td->notify_list_node, way_up_list); + td->notify_temp = trip->temperature; td->threshold -= trip->hysteresis; } @@ -452,10 +455,24 @@ static void thermal_zone_device_init(str pos->initialized = false; } +static int thermal_trip_notify_cmp(void *ascending, const struct list_head *a, + const struct list_head *b) +{ + struct thermal_trip_desc *tda = container_of(a, struct thermal_trip_desc, + notify_list_node); + struct thermal_trip_desc *tdb = container_of(b, struct thermal_trip_desc, + notify_list_node); + int ret = tdb->notify_temp - tda->notify_temp; + + return ascending ? ret : -ret; +} + void __thermal_zone_device_update(struct thermal_zone_device *tz, enum thermal_notify_event event) { struct thermal_trip_desc *td; + LIST_HEAD(way_down_list); + LIST_HEAD(way_up_list); if (tz->suspended) return; @@ -470,7 +487,19 @@ void __thermal_zone_device_update(struct tz->notify_event = event; for_each_trip_desc(tz, td) - handle_thermal_trip(tz, td); + handle_thermal_trip(tz, td, &way_up_list, &way_down_list); + + list_sort(&way_up_list, &way_up_list, thermal_trip_notify_cmp); + list_for_each_entry(td, &way_up_list, notify_list_node) { + thermal_notify_tz_trip_up(tz, &td->trip); + thermal_debug_tz_trip_up(tz, &td->trip); + } + + list_sort(NULL, &way_down_list, thermal_trip_notify_cmp); + list_for_each_entry(td, &way_down_list, notify_list_node) { + thermal_notify_tz_trip_down(tz, &td->trip); + thermal_debug_tz_trip_down(tz, &td->trip); + } monitor_thermal_zone(tz); } Index: linux-pm/drivers/thermal/thermal_core.h =================================================================== --- linux-pm.orig/drivers/thermal/thermal_core.h +++ linux-pm/drivers/thermal/thermal_core.h @@ -17,6 +17,8 @@ struct thermal_trip_desc { struct thermal_trip trip; + struct list_head notify_list_node; + int notify_temp; int threshold; };