drm: rework delayed connector cleanup in connector_iter

[mirror_ubuntu-bionic-kernel.git] / drivers / gpu / drm / drm_connector.c

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index c4dfcbc861a1523d7fde924b3d932d5be8759ec4..9ae236036e324c345177bcb8f9cd84b20110a582 100644 (file)
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -152,14 +152,23 @@ static void drm_connector_free(struct kref *kref)
        connector->funcs->destroy(connector);
 }
 
-static void drm_connector_free_work_fn(struct work_struct *work)
+void drm_connector_free_work_fn(struct work_struct *work)
 {
-       struct drm_connector *connector =
-               container_of(work, struct drm_connector, free_work);
-       struct drm_device *dev = connector->dev;
+       struct drm_connector *connector, *n;
+       struct drm_device *dev =
+               container_of(work, struct drm_device, mode_config.connector_free_work);
+       struct drm_mode_config *config = &dev->mode_config;
+       unsigned long flags;
+       struct llist_node *freed;
 
-       drm_mode_object_unregister(dev, &connector->base);
-       connector->funcs->destroy(connector);
+       spin_lock_irqsave(&config->connector_list_lock, flags);
+       freed = llist_del_all(&config->connector_free_list);
+       spin_unlock_irqrestore(&config->connector_list_lock, flags);
+
+       llist_for_each_entry_safe(connector, n, freed, free_node) {
+               drm_mode_object_unregister(dev, &connector->base);
+               connector->funcs->destroy(connector);
+       }
 }
 
 /**
@@ -191,8 +200,6 @@ int drm_connector_init(struct drm_device *dev,
        if (ret)
                return ret;
 
-       INIT_WORK(&connector->free_work, drm_connector_free_work_fn);
-
        connector->base.properties = &connector->properties;
        connector->dev = dev;
        connector->funcs = funcs;
@@ -547,10 +554,17 @@ EXPORT_SYMBOL(drm_connector_list_iter_begin);
  * actually release the connector when dropping our final reference.
  */
 static void
-drm_connector_put_safe(struct drm_connector *conn)
+__drm_connector_put_safe(struct drm_connector *conn)
 {
-       if (refcount_dec_and_test(&conn->base.refcount.refcount))
-               schedule_work(&conn->free_work);
+       struct drm_mode_config *config = &conn->dev->mode_config;
+
+       lockdep_assert_held(&config->connector_list_lock);
+
+       if (!refcount_dec_and_test(&conn->base.refcount.refcount))
+               return;
+
+       llist_add(&conn->free_node, &config->connector_free_list);
+       schedule_work(&config->connector_free_work);
 }
 
 /**
@@ -582,10 +596,10 @@ drm_connector_list_iter_next(struct drm_connector_list_iter *iter)
 
                /* loop until it's not a zombie connector */
        } while (!kref_get_unless_zero(&iter->conn->base.refcount));
-       spin_unlock_irqrestore(&config->connector_list_lock, flags);
 
        if (old_conn)
-               drm_connector_put_safe(old_conn);
+               __drm_connector_put_safe(old_conn);
+       spin_unlock_irqrestore(&config->connector_list_lock, flags);
 
        return iter->conn;
 }
@@ -602,9 +616,15 @@ EXPORT_SYMBOL(drm_connector_list_iter_next);
  */
 void drm_connector_list_iter_end(struct drm_connector_list_iter *iter)
 {
+       struct drm_mode_config *config = &iter->dev->mode_config;
+       unsigned long flags;
+
        iter->dev = NULL;
-       if (iter->conn)
-               drm_connector_put_safe(iter->conn);
+       if (iter->conn) {
+               spin_lock_irqsave(&config->connector_list_lock, flags);
+               __drm_connector_put_safe(iter->conn);
+               spin_unlock_irqrestore(&config->connector_list_lock, flags);
+       }
        lock_release(&connector_list_iter_dep_map, 0, _RET_IP_);
 }
 EXPORT_SYMBOL(drm_connector_list_iter_end);