net/udp: do not touch skb->peeked unless really needed

[karo-tx-linux.git] / net / core / datagram.c

diff --git a/net/core/datagram.c b/net/core/datagram.c
index 49816af8586bb832e806972b486588041a99524c..9482037a5c8c64aec79e42c65bd2691bdd9450a3 100644 (file)
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -214,6 +214,7 @@ struct sk_buff *__skb_try_recv_datagram(struct sock *sk, unsigned int flags,
        if (error)
                goto no_packet;
 
+       *peeked = 0;
        do {
                /* Again only user level code calls this function, so nothing
                 * interrupt level will suddenly eat the receive_queue.
@@ -227,22 +228,22 @@ struct sk_buff *__skb_try_recv_datagram(struct sock *sk, unsigned int flags,
                spin_lock_irqsave(&queue->lock, cpu_flags);
                skb_queue_walk(queue, skb) {
                        *last = skb;
-                       *peeked = skb->peeked;
                        if (flags & MSG_PEEK) {
                                if (_off >= skb->len && (skb->len || _off ||
                                                         skb->peeked)) {
                                        _off -= skb->len;
                                        continue;
                                }
-
-                               skb = skb_set_peeked(skb);
-                               error = PTR_ERR(skb);
-                               if (IS_ERR(skb)) {
-                                       spin_unlock_irqrestore(&queue->lock,
-                                                              cpu_flags);
-                                       goto no_packet;
+                               if (!skb->len) {
+                                       skb = skb_set_peeked(skb);
+                                       if (IS_ERR(skb)) {
+                                               error = PTR_ERR(skb);
+                                               spin_unlock_irqrestore(&queue->lock,
+                                                                      cpu_flags);
+                                               goto no_packet;
+                                       }
                                }
-
+                               *peeked = 1;
                                atomic_inc(&skb->users);
                        } else {
                                __skb_unlink(skb, queue);