net offloading: Pass features into netif_needs_gso().

Now that there is a single function that can compute the device
features relevant to a packet, we don't want to run it for each
offload.  This converts netif_needs_gso() to take the features
of the device, rather than computing them itself.
Signed-off-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/xen-netfront.c

@@ -488,7 +488,7 @@ static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	if (unlikely(!netif_carrier_ok(dev) ||
 		     (frags > 1 && !xennet_can_sg(dev)) ||
-		     netif_needs_gso(dev, skb))) {
+		     netif_needs_gso(skb, netif_skb_features(skb)))) {
 		spin_unlock_irq(&np->tx_lock);
 		goto drop;
 	}

include/linux/netdevice.h

@@ -2317,16 +2317,10 @@ static inline int skb_gso_ok(struct sk_buff *skb, int features)
 	       (!skb_has_frag_list(skb) || (features & NETIF_F_FRAGLIST));
 }
 
-static inline int netif_needs_gso(struct net_device *dev, struct sk_buff *skb)
+static inline int netif_needs_gso(struct sk_buff *skb, int features)
 {
-	if (skb_is_gso(skb)) {
-		int features = netif_skb_features(skb);
-
-		return (!skb_gso_ok(skb, features) ||
-			unlikely(skb->ip_summed != CHECKSUM_PARTIAL));
-	}
-
-	return 0;
+	return skb_is_gso(skb) && (!skb_gso_ok(skb, features) ||
+		unlikely(skb->ip_summed != CHECKSUM_PARTIAL));
 }
 
 static inline void netif_set_gso_max_size(struct net_device *dev,

net/core/dev.c

@@ -2086,6 +2086,8 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
 	int rc = NETDEV_TX_OK;
 
 	if (likely(!skb->next)) {
+		int features;
+
 		/*
 		 * If device doesnt need skb->dst, release it right now while
 		 * its hot in this cpu cache
@@ -2098,8 +2100,10 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
 
 		skb_orphan_try(skb);
 
+		features = netif_skb_features(skb);
+
 		if (vlan_tx_tag_present(skb) &&
-		    !(dev->features & NETIF_F_HW_VLAN_TX)) {
+		    !(features & NETIF_F_HW_VLAN_TX)) {
 			skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb));
 			if (unlikely(!skb))
 				goto out;
@@ -2107,7 +2111,7 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
 			skb->vlan_tci = 0;
 		}
 
-		if (netif_needs_gso(dev, skb)) {
+		if (netif_needs_gso(skb, features)) {
 			if (unlikely(dev_gso_segment(skb)))
 				goto out_kfree_skb;
 			if (skb->next)