drivers: base: Reduce device link removal code duplication

Reduce device link removal code duplication between the cases when
SRCU is enabled and when it is disabled by moving the only differing
piece of it (which is the removal of the link from the consumer and
supplier lists) into a separate wrapper function (defined differently
for each of the cases in question).

No intentional functional impact.

Reviewed-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/4326215.LvFx2qVVIh@kreacher
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: rafaeljw

drivers/base/core.c

@@ -199,6 +199,12 @@ static void device_link_synchronize_removal(void)
 {
 	synchronize_srcu(&device_links_srcu);
 }
+
+static void device_link_remove_from_lists(struct device_link *link)
+{
+	list_del_rcu(&link->s_node);
+	list_del_rcu(&link->c_node);
+}
 #else /* !CONFIG_SRCU */
 static DECLARE_RWSEM(device_links_lock);
 
@@ -233,6 +239,12 @@ int device_links_read_lock_held(void)
 static inline void device_link_synchronize_removal(void)
 {
 }
+
+static void device_link_remove_from_lists(struct device_link *link)
+{
+	list_del(&link->s_node);
+	list_del(&link->c_node);
+}
 #endif /* !CONFIG_SRCU */
 
 static bool device_is_ancestor(struct device *dev, struct device *target)
@@ -855,7 +867,6 @@ struct device_link *device_link_add(struct device *consumer,
 }
 EXPORT_SYMBOL_GPL(device_link_add);
 
-#ifdef CONFIG_SRCU
 static void __device_link_del(struct kref *kref)
 {
 	struct device_link *link = container_of(kref, struct device_link, kref);
@@ -865,25 +876,9 @@ static void __device_link_del(struct kref *kref)
 
 	pm_runtime_drop_link(link);
 
-	list_del_rcu(&link->s_node);
-	list_del_rcu(&link->c_node);
-	device_unregister(&link->link_dev);
-}
-#else /* !CONFIG_SRCU */
-static void __device_link_del(struct kref *kref)
-{
-	struct device_link *link = container_of(kref, struct device_link, kref);
-
-	dev_info(link->consumer, "Dropping the link to %s\n",
-		 dev_name(link->supplier));
-
-	pm_runtime_drop_link(link);
-
-	list_del(&link->s_node);
-	list_del(&link->c_node);
+	device_link_remove_from_lists(link);
 	device_unregister(&link->link_dev);
 }
-#endif /* !CONFIG_SRCU */
 
 static void device_link_put_kref(struct device_link *link)
 {