[SKB]: __skb_dequeue = skb_peek + __skb_unlink

By rearranging the order of declarations, __skb_dequeue() is expressed in terms of

 * skb_peek() and
 * __skb_unlink(),

thus in effect mirroring the analogue implementation of __skb_dequeue_tail().

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index e517701..c211620 100644 (file)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -734,35 +734,6 @@ static inline void __skb_queue_tail(struct sk_buff_head *list,
        next->prev  = prev->next = newsk;
 }
 
-
-/**
- *     __skb_dequeue - remove from the head of the queue
- *     @list: list to dequeue from
- *
- *     Remove the head of the list. This function does not take any locks
- *     so must be used with appropriate locks held only. The head item is
- *     returned or %NULL if the list is empty.
- */
-extern struct sk_buff *skb_dequeue(struct sk_buff_head *list);
-static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
-{
-       struct sk_buff *next, *prev, *result;
-
-       prev = (struct sk_buff *) list;
-       next = prev->next;
-       result = NULL;
-       if (next != prev) {
-               result       = next;
-               next         = next->next;
-               list->qlen--;
-               next->prev   = prev;
-               prev->next   = next;
-               result->next = result->prev = NULL;
-       }
-       return result;
-}
-
-
 /*
  *     Insert a packet on a list.
  */
@@ -803,8 +774,22 @@ static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
        prev->next = next;
 }
 
-
-/* XXX: more streamlined implementation */
+/**
+ *     __skb_dequeue - remove from the head of the queue
+ *     @list: list to dequeue from
+ *
+ *     Remove the head of the list. This function does not take any locks
+ *     so must be used with appropriate locks held only. The head item is
+ *     returned or %NULL if the list is empty.
+ */
+extern struct sk_buff *skb_dequeue(struct sk_buff_head *list);
+static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
+{
+       struct sk_buff *skb = skb_peek(list);
+       if (skb)
+               __skb_unlink(skb, list);
+       return skb;
+}
 
 /**
  *     __skb_dequeue_tail - remove from the tail of the queue