From patchwork Mon Sep 14 17:32:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Tony Nguyen X-Patchwork-Id: 1363839 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=intel.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4Bqtkk1JRRz9sTC for ; Tue, 15 Sep 2020 03:33:50 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726038AbgINRdr (ORCPT ); Mon, 14 Sep 2020 13:33:47 -0400 Received: from mga09.intel.com ([134.134.136.24]:61353 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726306AbgINRcl (ORCPT ); Mon, 14 Sep 2020 13:32:41 -0400 IronPort-SDR: KHm7dtWl1kJCyqI22z5p6PjPKFqjOs98BHNSLQzoZBjUwnRC4zLmP/ZdIpqKHXQ2svrY4GOM42 ZTM2lx8wpmqw== X-IronPort-AV: E=McAfee;i="6000,8403,9744"; a="160056114" X-IronPort-AV: E=Sophos;i="5.76,426,1592895600"; d="scan'208";a="160056114" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Sep 2020 10:32:31 -0700 IronPort-SDR: ZjdwJWkvWTxX2r/h91TWvxi10LE62XFsYLZXCIqWZODXTbFix+allIQ78EVBlCVv2YrFDxtTx0 JCMpmyE4H8QA== X-IronPort-AV: E=Sophos;i="5.76,426,1592895600"; d="scan'208";a="319137317" Received: from jtkirshe-desk1.jf.intel.com ([134.134.177.86]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Sep 2020 10:32:31 -0700 From: Tony Nguyen To: davem@davemloft.net Cc: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , netdev@vger.kernel.org, nhorman@redhat.com, sassmann@redhat.com, jeffrey.t.kirsher@intel.com, anthony.l.nguyen@intel.com, Aaron Brown Subject: [net-next v2 3/5] i40e, xsk: remove HW descriptor prefetch in AF_XDP path Date: Mon, 14 Sep 2020 10:32:22 -0700 Message-Id: <20200914173224.692707-4-anthony.l.nguyen@intel.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200914173224.692707-1-anthony.l.nguyen@intel.com> References: <20200914173224.692707-1-anthony.l.nguyen@intel.com> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Björn Töpel The software prefetching of HW descriptors has a negative impact on the performance. Therefore, it is now removed. Performance for the rx_drop benchmark increased with 2%. Signed-off-by: Björn Töpel Tested-by: Aaron Brown Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/i40e/i40e_txrx.c | 13 +++++++++++++ drivers/net/ethernet/intel/i40e/i40e_txrx_common.h | 13 ------------- drivers/net/ethernet/intel/i40e/i40e_xsk.c | 12 ++++++++++++ 3 files changed, 25 insertions(+), 13 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c index 8500e1c1a16b..b43bc20f701d 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c @@ -2295,6 +2295,19 @@ void i40e_finalize_xdp_rx(struct i40e_ring *rx_ring, unsigned int xdp_res) } } +/** + * i40e_inc_ntc: Advance the next_to_clean index + * @rx_ring: Rx ring + **/ +static void i40e_inc_ntc(struct i40e_ring *rx_ring) +{ + u32 ntc = rx_ring->next_to_clean + 1; + + ntc = (ntc < rx_ring->count) ? ntc : 0; + rx_ring->next_to_clean = ntc; + prefetch(I40E_RX_DESC(rx_ring, ntc)); +} + /** * i40e_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf * @rx_ring: rx descriptor ring to transact packets on diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h b/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h index 667c4dc4b39f..1397dd3c1c57 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx_common.h @@ -99,19 +99,6 @@ static inline bool i40e_rx_is_programming_status(u64 qword1) return qword1 & I40E_RXD_QW1_LENGTH_SPH_MASK; } -/** - * i40e_inc_ntc: Advance the next_to_clean index - * @rx_ring: Rx ring - **/ -static inline void i40e_inc_ntc(struct i40e_ring *rx_ring) -{ - u32 ntc = rx_ring->next_to_clean + 1; - - ntc = (ntc < rx_ring->count) ? ntc : 0; - rx_ring->next_to_clean = ntc; - prefetch(I40E_RX_DESC(rx_ring, ntc)); -} - void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring); void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring); bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi); diff --git a/drivers/net/ethernet/intel/i40e/i40e_xsk.c b/drivers/net/ethernet/intel/i40e/i40e_xsk.c index 2a1153d8957b..cf48758447c2 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_xsk.c +++ b/drivers/net/ethernet/intel/i40e/i40e_xsk.c @@ -257,6 +257,18 @@ static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring, return skb; } +/** + * i40e_inc_ntc: Advance the next_to_clean index + * @rx_ring: Rx ring + **/ +static void i40e_inc_ntc(struct i40e_ring *rx_ring) +{ + u32 ntc = rx_ring->next_to_clean + 1; + + ntc = (ntc < rx_ring->count) ? ntc : 0; + rx_ring->next_to_clean = ntc; +} + /** * i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring * @rx_ring: Rx ring