[PATCH] small loopback.c cleanups

[Mitchell Blank Jr <mitch@xxxxxxxxxx>]

Few trivial cleanups/improvements to drivers/net/loopback.c  Seems to work
fine for me, although I don't know how to stress all of the code paths.

Patch is versus 2.6.0-test3 (should apply to current BK fine)

-Mitch

--- linux-2.6.0-test3-VIRGIN/drivers/net/loopback.c     2003-07-13 
20:30:48.000000000 -0700
+++ linux-2.6.0-test3mnb1/drivers/net/loopback.c        2003-08-16 
08:37:29.000000000 -0700
@@ -128,17 +128,13 @@
         *      instead are lobbed from tx queue to rx queue 
         */
 
-       if(atomic_read(&skb->users) != 1)
-       {
+       if (skb_shared(skb)) {
                struct sk_buff *skb2=skb;
                skb=skb_clone(skb, GFP_ATOMIC);         /* Clone the buffer */
-               if(skb==NULL) {
-                       kfree_skb(skb2);
+               kfree_skb(skb2);
+               if (unlikely(skb==NULL))
                        return 0;
-               }
-               kfree_skb(skb2);
-       }
-       else
+       } else
                skb_orphan(skb);
 
        skb->protocol=eth_type_trans(skb,dev);
@@ -148,12 +144,8 @@
 #endif
 
        if (skb_shinfo(skb)->tso_size) {
-               struct iphdr *iph = skb->nh.iph;
-
-               if (skb->protocol != htons(ETH_P_IP))
-                       BUG();
-               if (iph->protocol != IPPROTO_TCP)
-                       BUG();
+               BUG_ON(skb->protocol != htons(ETH_P_IP));
+               BUG_ON(skb->nh.iph->protocol != IPPROTO_TCP);
 
                emulate_large_send_offload(skb);
                return 0;