Commit 4157e287 authored by Jiri Pirko's avatar Jiri Pirko Committed by Ben Hutchings

list: introduce list_first_entry_or_null

commit 6d7581e6 upstream.

non-rcu variant of list_first_or_null_rcu
Signed-off-by: default avatarJiri Pirko <jiri@resnulli.us>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
parent bbaa1c66
...@@ -361,6 +361,17 @@ static inline void list_splice_tail_init(struct list_head *list, ...@@ -361,6 +361,17 @@ static inline void list_splice_tail_init(struct list_head *list,
#define list_first_entry(ptr, type, member) \ #define list_first_entry(ptr, type, member) \
list_entry((ptr)->next, type, member) 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 * list_for_each - iterate over a list
* @pos: the &struct list_head to use as a loop cursor. * @pos: the &struct list_head to use as a loop cursor.
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment