[PATCH 3.2 201/202] list: introduce list_first_entry_or_null

[Ben Hutchings]

3.2.87-rc2 review patch.  If anyone has any objections, please let me know.

------------------

From: Jiri Pirko <jiri@xxxxxxxxxxx>

commit 6d7581e62f8be462440d7b22c6361f7c9fa4902b upstream.

non-rcu variant of list_first_or_null_rcu

Signed-off-by: Jiri Pirko <jiri@xxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 include/linux/list.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/include/linux/list.h b/include/linux/list.h
index 6a1f8df9144b..b83e5657365a 100644
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -362,6 +362,17 @@ static inline void list_splice_tail_init(struct list_head *list,
 	list_entry((ptr)->next, type, member)
 
 /**
+ * list_first_entry_or_null - get the first element from a list
+ * @ptr:	the list head to take the element from.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_struct within the struct.
+ *
+ * Note that if the list is empty, it returns NULL.
+ */
+#define list_first_entry_or_null(ptr, type, member) \
+	(!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL)
+
+/**
  * list_for_each	-	iterate over a list
  * @pos:	the &struct list_head to use as a loop cursor.
  * @head:	the head for your list.