- * Retry if another thread removed all but one of duplicates
- * since check (this check was performed without lock).
- * Ensure that the node we are about to remove is still in the
- * list (while holding lock).
+ * Find the previous node's next pointer pointing to our node,
+ * so we can update it. Retry if another thread removed all but
+ * one of duplicates since check (this check was performed
+ * without lock). Ensure that the node we are about to remove is
+ * still in the list (while holding lock). No need for RCU
+ * traversal here since we hold the lock on the parent.