From: Stephen Hemminger <shemminger@vyatta.com>
Date: Thu, 21 Jun 2012 02:15:10 +0000 (+0000)
Subject: ixgbe: simplify padding and length checks
X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=f73332fc39e35a6ac14f892390adcd34a63b00d3;p=~shefty%2Frdma-dev.git

ixgbe: simplify padding and length checks

The check for length <= 0 is bogus because length is unsigned, and network
stack never sends zero length packets (unless it is totally broken).

The check for really small packets can be optimized (using unlikely)
and calling skb_pad directly.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index b0ddfd47e47..69a660b5621 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -6380,17 +6380,12 @@ static netdev_tx_t ixgbe_xmit_frame(struct sk_buff *skb,
 	struct ixgbe_adapter *adapter = netdev_priv(netdev);
 	struct ixgbe_ring *tx_ring;
 
-	if (skb->len <= 0) {
-		dev_kfree_skb_any(skb);
-		return NETDEV_TX_OK;
-	}
-
 	/*
 	 * The minimum packet size for olinfo paylen is 17 so pad the skb
 	 * in order to meet this minimum size requirement.
 	 */
-	if (skb->len < 17) {
-		if (skb_padto(skb, 17))
+	if (unlikely(skb->len < 17)) {
+		if (skb_pad(skb, 17 - skb->len))
 			return NETDEV_TX_OK;
 		skb->len = 17;
 	}