thermal: core: Store trip sysfs attributes in thermal_trip_desc

Instead of allocating memory for trip point sysfs attributes separately,
store them in struct thermal_trip_desc for each trip individually which
allows a few extra memory allocations to be avoided.

No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/46571375.fMDQidcC6G@rjwysocki.net

drivers/thermal/thermal_core.h

@@ -15,8 +15,20 @@
 #include "thermal_netlink.h"
 #include "thermal_debugfs.h"
 
+struct thermal_attr {
+	struct device_attribute attr;
+	char name[THERMAL_NAME_LENGTH];
+};
+
+struct thermal_trip_attrs {
+	struct thermal_attr type;
+	struct thermal_attr temp;
+	struct thermal_attr hyst;
+};
+
 struct thermal_trip_desc {
 	struct thermal_trip trip;
+	struct thermal_trip_attrs trip_attrs;
 	struct list_head notify_list_node;
 	int notify_temp;
 	int threshold;
@@ -56,9 +68,6 @@ struct thermal_governor {
  * @device:	&struct device for this thermal zone
  * @removal:	removal completion
  * @resume:	resume completion
- * @trip_temp_attrs:	attributes for trip points for sysfs: trip temperature
- * @trip_type_attrs:	attributes for trip points for sysfs: trip type
- * @trip_hyst_attrs:	attributes for trip points for sysfs: trip hysteresis
  * @mode:		current mode of this thermal zone
  * @devdata:	private pointer for device private data
  * @num_trips:	number of trip points the thermal zone supports
@@ -102,9 +111,6 @@ struct thermal_zone_device {
 	struct completion removal;
 	struct completion resume;
 	struct attribute_group trips_attribute_group;
-	struct thermal_attr *trip_temp_attrs;
-	struct thermal_attr *trip_type_attrs;
-	struct thermal_attr *trip_hyst_attrs;
 	enum thermal_device_mode mode;
 	void *devdata;
 	int num_trips;
@@ -188,11 +194,6 @@ int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 
 struct thermal_zone_device *thermal_zone_get_by_id(int id);
 
-struct thermal_attr {
-	struct device_attribute attr;
-	char name[THERMAL_NAME_LENGTH];
-};
-
 static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev)
 {
 	return cdev->ops->get_requested_power && cdev->ops->state2power &&

drivers/thermal/thermal_sysfs.c

@@ -382,87 +382,55 @@ static const struct attribute_group *thermal_zone_attribute_groups[] = {
  */
 static int create_trip_attrs(struct thermal_zone_device *tz)
 {
-	const struct thermal_trip_desc *td;
+	struct thermal_trip_desc *td;
 	struct attribute **attrs;
-
-	/* This function works only for zones with at least one trip */
-	if (tz->num_trips <= 0)
-		return -EINVAL;
-
-	tz->trip_type_attrs = kcalloc(tz->num_trips, sizeof(*tz->trip_type_attrs),
-				      GFP_KERNEL);
-	if (!tz->trip_type_attrs)
-		return -ENOMEM;
-
-	tz->trip_temp_attrs = kcalloc(tz->num_trips, sizeof(*tz->trip_temp_attrs),
-				      GFP_KERNEL);
-	if (!tz->trip_temp_attrs) {
-		kfree(tz->trip_type_attrs);
-		return -ENOMEM;
-	}
-
-	tz->trip_hyst_attrs = kcalloc(tz->num_trips,
-				      sizeof(*tz->trip_hyst_attrs),
-				      GFP_KERNEL);
-	if (!tz->trip_hyst_attrs) {
-		kfree(tz->trip_type_attrs);
-		kfree(tz->trip_temp_attrs);
-		return -ENOMEM;
-	}
+	int i;
 
 	attrs = kcalloc(tz->num_trips * 3 + 1, sizeof(*attrs), GFP_KERNEL);
-	if (!attrs) {
-		kfree(tz->trip_type_attrs);
-		kfree(tz->trip_temp_attrs);
-		kfree(tz->trip_hyst_attrs);
+	if (!attrs)
 		return -ENOMEM;
-	}
 
+	i = 0;
 	for_each_trip_desc(tz, td) {
-		int indx = thermal_zone_trip_id(tz, &td->trip);
+		struct thermal_trip_attrs *trip_attrs = &td->trip_attrs;
 
 		/* create trip type attribute */
-		snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
-			 "trip_point_%d_type", indx);
+		snprintf(trip_attrs->type.name, THERMAL_NAME_LENGTH,
+			 "trip_point_%d_type", i);
 
-		sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
-		tz->trip_type_attrs[indx].attr.attr.name =
-						tz->trip_type_attrs[indx].name;
-		tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
-		tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
-		attrs[indx] = &tz->trip_type_attrs[indx].attr.attr;
+		sysfs_attr_init(&trip_attrs->type.attr.attr);
+		trip_attrs->type.attr.attr.name = trip_attrs->type.name;
+		trip_attrs->type.attr.attr.mode = S_IRUGO;
+		trip_attrs->type.attr.show = trip_point_type_show;
+		attrs[i] = &trip_attrs->type.attr.attr;
 
 		/* create trip temp attribute */
-		snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
-			 "trip_point_%d_temp", indx);
-
-		sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
-		tz->trip_temp_attrs[indx].attr.attr.name =
-						tz->trip_temp_attrs[indx].name;
-		tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
-		tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
+		snprintf(trip_attrs->temp.name, THERMAL_NAME_LENGTH,
+			 "trip_point_%d_temp", i);
+
+		sysfs_attr_init(&trip_attrs->temp.attr.attr);
+		trip_attrs->temp.attr.attr.name = trip_attrs->temp.name;
+		trip_attrs->temp.attr.attr.mode = S_IRUGO;
+		trip_attrs->temp.attr.show = trip_point_temp_show;
 		if (td->trip.flags & THERMAL_TRIP_FLAG_RW_TEMP) {
-			tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
-			tz->trip_temp_attrs[indx].attr.store =
-							trip_point_temp_store;
+			trip_attrs->temp.attr.attr.mode |= S_IWUSR;
+			trip_attrs->temp.attr.store = trip_point_temp_store;
 		}
-		attrs[indx + tz->num_trips] = &tz->trip_temp_attrs[indx].attr.attr;
+		attrs[i + tz->num_trips] = &trip_attrs->temp.attr.attr;
 
-		snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
-			 "trip_point_%d_hyst", indx);
+		snprintf(trip_attrs->hyst.name, THERMAL_NAME_LENGTH,
+			 "trip_point_%d_hyst", i);
 
-		sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
-		tz->trip_hyst_attrs[indx].attr.attr.name =
-					tz->trip_hyst_attrs[indx].name;
-		tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
-		tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
+		sysfs_attr_init(&trip_attrs->hyst.attr.attr);
+		trip_attrs->hyst.attr.attr.name = trip_attrs->hyst.name;
+		trip_attrs->hyst.attr.attr.mode = S_IRUGO;
+		trip_attrs->hyst.attr.show = trip_point_hyst_show;
 		if (td->trip.flags & THERMAL_TRIP_FLAG_RW_HYST) {
-			tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
-			tz->trip_hyst_attrs[indx].attr.store =
-					trip_point_hyst_store;
+			trip_attrs->hyst.attr.attr.mode |= S_IWUSR;
+			trip_attrs->hyst.attr.store = trip_point_hyst_store;
 		}
-		attrs[indx + tz->num_trips * 2] =
-					&tz->trip_hyst_attrs[indx].attr.attr;
+		attrs[i + 2 * tz->num_trips] = &trip_attrs->hyst.attr.attr;
+		i++;
 	}
 	attrs[tz->num_trips * 3] = NULL;
 
@@ -479,13 +447,8 @@ static int create_trip_attrs(struct thermal_zone_device *tz)
  */
 static void destroy_trip_attrs(struct thermal_zone_device *tz)
 {
-	if (!tz)
-		return;
-
-	kfree(tz->trip_type_attrs);
-	kfree(tz->trip_temp_attrs);
-	kfree(tz->trip_hyst_attrs);
-	kfree(tz->trips_attribute_group.attrs);
+	if (tz)
+		kfree(tz->trips_attribute_group.attrs);
 }
 
 int thermal_zone_create_device_groups(struct thermal_zone_device *tz)