From patchwork Mon Apr 27 18:57:08 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Catherine Sullivan X-Patchwork-Id: 465186 X-Patchwork-Delegate: jeffrey.t.kirsher@intel.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from hemlock.osuosl.org (hemlock.osuosl.org [140.211.166.133]) by ozlabs.org (Postfix) with ESMTP id 9E2A914007D for ; Tue, 28 Apr 2015 04:54:43 +1000 (AEST) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id E852B94E82; Mon, 27 Apr 2015 18:54:42 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id D6Bx4kbx2me1; Mon, 27 Apr 2015 18:54:41 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by hemlock.osuosl.org (Postfix) with ESMTP id B8F2994E7E; Mon, 27 Apr 2015 18:54:41 +0000 (UTC) X-Original-To: intel-wired-lan@lists.osuosl.org Delivered-To: intel-wired-lan@lists.osuosl.org Received: from whitealder.osuosl.org (whitealder.osuosl.org [140.211.166.138]) by ash.osuosl.org (Postfix) with ESMTP id 19CED1C21C0 for ; Mon, 27 Apr 2015 18:54:41 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 156CC8B8A7 for ; Mon, 27 Apr 2015 18:54:41 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id J9X5cueH7pzi for ; Mon, 27 Apr 2015 18:54:40 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by whitealder.osuosl.org (Postfix) with ESMTP id 8AEE48B694 for ; Mon, 27 Apr 2015 18:54:40 +0000 (UTC) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga102.fm.intel.com with ESMTP; 27 Apr 2015 11:54:40 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,658,1422950400"; d="scan'208";a="486315434" Received: from catheri1-tigger.jf.intel.com ([134.134.176.92]) by FMSMGA003.fm.intel.com with ESMTP; 27 Apr 2015 11:54:40 -0700 From: Catherine Sullivan To: intel-wired-lan@lists.osuosl.org Date: Mon, 27 Apr 2015 14:57:08 -0400 Message-Id: <1430161042-28494-2-git-send-email-catherine.sullivan@intel.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1430161042-28494-1-git-send-email-catherine.sullivan@intel.com> References: <1430161042-28494-1-git-send-email-catherine.sullivan@intel.com> Subject: [Intel-wired-lan] [net-next S5 01/15] i40e/i40evf: improve tx performance with a small tweak X-BeenThere: intel-wired-lan@lists.osuosl.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Intel Wired Ethernet Linux Kernel Driver Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-wired-lan-bounces@lists.osuosl.org Sender: "Intel-wired-lan" From: Jesse Brandeburg Add a prefetch for the next tx descriptor to be used when we know there are more coming. Signed-off-by: Jesse Brandeburg Change-ID: Ibb9acab11d508eec2db7da795df74debc16eeacb Tested-by: Jim Young --- drivers/net/ethernet/intel/i40e/i40e_txrx.c | 2 ++ drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c index e1596dc..74022ac 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c @@ -2623,6 +2623,8 @@ static inline void i40e_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb, netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev, tx_ring->queue_index))) writel(i, tx_ring->tail); + else + prefetchw(tx_desc + 1); return; diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c index 11de5a5..e629762 100644 --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c @@ -1844,6 +1844,8 @@ static inline void i40evf_tx_map(struct i40e_ring *tx_ring, struct sk_buff *skb, netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev, tx_ring->queue_index))) writel(i, tx_ring->tail); + else + prefetchw(tx_desc + 1); return;