Re: [PATCH v1 03/10] thermal: core: Prepare for moving trips between sorted lists

[Lukasz Luba <lukasz.luba@arm.com>]

On 10/16/24 12:24, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> 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>
> ---
>   drivers/thermal/thermal_core.c |   25 ++++++++++++++++++-------
>   1 file changed, 18 insertions(+), 7 deletions(-)
> 
> Index: linux-pm/drivers/thermal/thermal_core.c
> ===================================================================
> --- linux-pm.orig/drivers/thermal/thermal_core.c
> +++ linux-pm/drivers/thermal/thermal_core.c
> @@ -408,11 +408,17 @@ static void handle_critical_trips(struct
>   		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 t
>   		 */
>   		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 t
>   		 * 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
>   				  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_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);
> @@ -1490,6 +1500,7 @@ thermal_zone_device_register_with_trips(
>   	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
> 
> 
> 

Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>