net: trans_start cleanups

Now that core network takes care of trans_start updates, dont do it
in drivers themselves, if possible. Drivers can avoid one cache miss
(on dev->trans_start) in their start_xmit() handler.

Exceptions are NETIF_F_LLTX drivers

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tulip/tulip_core.c b/drivers/net/tulip/tulip_core.c
index 22e766e..254643e 100644
--- a/drivers/net/tulip/tulip_core.c
+++ b/drivers/net/tulip/tulip_core.c
@@ -605,7 +605,7 @@
 
 out_unlock:
 	spin_unlock_irqrestore (&tp->lock, flags);
-	dev->trans_start = jiffies;
+	dev->trans_start = jiffies; /* prevent tx timeout */
 	netif_wake_queue (dev);
 }
 
@@ -707,8 +707,6 @@
 
 	spin_unlock_irqrestore(&tp->lock, flags);
 
-	dev->trans_start = jiffies;
-
 	return NETDEV_TX_OK;
 }