From: Jie Liu <jeff....@oracle.com>
Introduce a trivial helper list_last_entry_or_null() to fetch the
last entry from a list, return NULL if the list is empty.
Signed-off-by: Jie Liu <jeff....@oracle.com>
---
include/linux/list.h | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/include/linux/list.h b/include/linux/list.h
index ef95941..3337249 100644
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -384,6 +384,17 @@ static inline void list_splice_tail_init(struct list_head
*list,
(!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL)
/**
+ * list_last_entry_or_null - get the last 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_last_entry_or_null(ptr, type, member) \
+ (!list_empty(ptr) ? list_last_entry(ptr, type, member) : NULL)
+
+/**
* list_next_entry - get the next element in list
* @pos: the type * to cursor
* @member: the name of the list_struct within the struct.
--
1.8.3.2
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