hlist: Add hlist_is_singular_node() helper

[cascardo/linux.git] / include / linux / list.h

diff --git a/include/linux/list.h b/include/linux/list.h
index 5356f4d..5183138 100644 (file)
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -678,6 +678,16 @@ static inline bool hlist_fake(struct hlist_node *h)
        return h->pprev == &h->next;
 }
 
+/*
+ * Check whether the node is the only node of the head without
+ * accessing head:
+ */
+static inline bool
+hlist_is_singular_node(struct hlist_node *n, struct hlist_head *h)
+{
+       return !n->next && n->pprev == &h->first;
+}
+
 /*
  * Move a list from one list head to another. Fixup the pprev
  * reference of the first entry if it exists.