skbuff: add check for non-linear to warn_if_lro and needs_linearize

We can avoid an unecessary cache miss by checking if the skb is non-linear
before accessing gso_size/gso_type in skb_warn_if_lro, the same can also be
done to avoid a cache miss on nr_frags if data_len is 0.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index bf243fc..645e78d 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2129,7 +2129,8 @@
 	/* LRO sets gso_size but not gso_type, whereas if GSO is really
 	 * wanted then gso_type will be set. */
 	struct skb_shared_info *shinfo = skb_shinfo(skb);
-	if (shinfo->gso_size != 0 && unlikely(shinfo->gso_type == 0)) {
+	if (skb_is_nonlinear(skb) && shinfo->gso_size != 0 &&
+	    unlikely(shinfo->gso_type == 0)) {
 		__skb_warn_lro_forwarding(skb);
 		return true;
 	}