thermal: core: Prepare for moving trips between sorted lists

Subsequently, trips will be moved between sorted lists in multiple
places, so replace add_trip_to_sorted_list() with an analogous
function, move_trip_to_sorted_list(), that will move a given trip
to a given sorted list.

To allow list_del() used in the new function to work, initialize the
list_node fields in trip descriptors where applicable so they are
always valid.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/2960197.e9J7NaK4W3@rjwysocki.net

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index e3cd8cd3502b7cdcdc208cff3ad7cca852332913..9252c89ec38e5243ba5741a3aa29d8ea0fa8973b 100644 (file)
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -408,11 +408,17 @@ static void handle_critical_trips(struct thermal_zone_device *tz,
                tz->ops.hot(tz);
 }
 
-static void add_trip_to_sorted_list(struct thermal_trip_desc *td,
-                                   struct list_head *list)
+static void move_trip_to_sorted_list(struct thermal_trip_desc *td,
+                                    struct list_head *list)
 {
        struct thermal_trip_desc *entry;
 
+       /*
+        * Delete upfront and then add to make relocation within the same list
+        * work.
+        */
+       list_del(&td->list_node);
+
        /* Assume that the new entry is likely to be the last one. */
        list_for_each_entry_reverse(entry, list, list_node) {
                if (entry->notify_temp <= td->notify_temp) {
@@ -453,7 +459,7 @@ static void handle_thermal_trip(struct thermal_zone_device *tz,
                 */
                if (tz->temperature < trip->temperature - trip->hysteresis) {
                        td->notify_temp = trip->temperature - trip->hysteresis;
-                       add_trip_to_sorted_list(td, way_down_list);
+                       move_trip_to_sorted_list(td, way_down_list);
 
                        if (trip->type == THERMAL_TRIP_PASSIVE) {
                                tz->passive--;
@@ -469,7 +475,7 @@ static void handle_thermal_trip(struct thermal_zone_device *tz,
                 * threshold is then set to the low temperature of the trip.
                 */
                td->notify_temp = trip->temperature;
-               add_trip_to_sorted_list(td, way_up_list);
+               move_trip_to_sorted_list(td, way_up_list);
 
                td->threshold -= trip->hysteresis;
 
@@ -538,7 +544,7 @@ void __thermal_zone_device_update(struct thermal_zone_device *tz,
                                  enum thermal_notify_event event)
 {
        struct thermal_governor *governor = thermal_get_tz_governor(tz);
-       struct thermal_trip_desc *td;
+       struct thermal_trip_desc *td, *next;
        LIST_HEAD(way_down_list);
        LIST_HEAD(way_up_list);
        int low = -INT_MAX, high = INT_MAX;
@@ -586,11 +592,15 @@ void __thermal_zone_device_update(struct thermal_zone_device *tz,
 
        thermal_zone_set_trips(tz, low, high);
 
-       list_for_each_entry(td, &way_up_list, list_node)
+       list_for_each_entry_safe(td, next, &way_up_list, list_node) {
                thermal_trip_crossed(tz, &td->trip, governor, true);
+               list_del_init(&td->list_node);
+       }
 
-       list_for_each_entry_reverse(td, &way_down_list, list_node)
+       list_for_each_entry_safe_reverse(td, next, &way_down_list, list_node) {
                thermal_trip_crossed(tz, &td->trip, governor, false);
+               list_del_init(&td->list_node);
+       }
 
        if (governor->manage)
                governor->manage(tz);
@@ -1484,6 +1494,7 @@ thermal_zone_device_register_with_trips(const char *type,
        for_each_trip_desc(tz, td) {
                td->trip = *trip++;
                INIT_LIST_HEAD(&td->thermal_instances);
+               INIT_LIST_HEAD(&td->list_node);
                /*
                 * Mark all thresholds as invalid to start with even though
                 * this only matters for the trips that start as invalid and