From patchwork Thu Jun 21 12:15:10 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirsher, Jeffrey T" X-Patchwork-Id: 166299 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 8ED1FB6FA3 for ; Thu, 21 Jun 2012 22:15:21 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759428Ab2FUMPT (ORCPT ); Thu, 21 Jun 2012 08:15:19 -0400 Received: from mga01.intel.com ([192.55.52.88]:30552 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757071Ab2FUMPR (ORCPT ); Thu, 21 Jun 2012 08:15:17 -0400 Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga101.fm.intel.com with ESMTP; 21 Jun 2012 05:15:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.71,315,1320652800"; d="scan'208";a="168484422" Received: from unknown (HELO jtkirshe-mobl.amr.corp.intel.com) ([10.255.12.68]) by fmsmga001.fm.intel.com with ESMTP; 21 Jun 2012 05:15:16 -0700 From: Jeff Kirsher To: davem@davemloft.net Cc: Stephen Hemminger , netdev@vger.kernel.org, gospo@redhat.com, sassmann@redhat.com, Jeff Kirsher Subject: [net] ixgbe: simplify padding and length checks Date: Thu, 21 Jun 2012 05:15:10 -0700 Message-Id: <1340280910-22651-1-git-send-email-jeffrey.t.kirsher@intel.com> X-Mailer: git-send-email 1.7.10.2 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Stephen Hemminger 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 Tested-by: Phil Schmitt Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index cbb05d6..9afe0cb 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -6383,17 +6383,12 @@ 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; }