From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 804ECC4320E for ; Thu, 5 Aug 2021 18:43:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5EB4660F01 for ; Thu, 5 Aug 2021 18:43:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241570AbhHESoE (ORCPT ); Thu, 5 Aug 2021 14:44:04 -0400 Received: from fllv0016.ext.ti.com ([198.47.19.142]:33964 "EHLO fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241568AbhHESoC (ORCPT ); Thu, 5 Aug 2021 14:44:02 -0400 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id 175IhhCt001060; Thu, 5 Aug 2021 13:43:43 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1628189023; bh=46JDL8MQEgeXUPygiDI9iRLIqECk9VxRHBRsZUVsTe0=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=bFzVWr8IUighh8u3JJL/AhOWz4wbdb5iju+RonuFifeBvPOIGI23vz1tur4qrRe1j A3khATTv+PEdRheUlpVj5wT9zzxitwVxlblKXE9tnNhNKF5KXV+jzw82CIjnNXVFzE 1FG+MtcFDzUmJ9yjT78ImAdn/3bT1g9ocqbgLhbQ= Received: from DFLE109.ent.ti.com (dfle109.ent.ti.com [10.64.6.30]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 175Ihhqe023395 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 5 Aug 2021 13:43:43 -0500 Received: from DFLE106.ent.ti.com (10.64.6.27) by DFLE109.ent.ti.com (10.64.6.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Thu, 5 Aug 2021 13:43:43 -0500 Received: from fllv0039.itg.ti.com (10.64.41.19) by DFLE106.ent.ti.com (10.64.6.27) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2 via Frontend Transport; Thu, 5 Aug 2021 13:43:43 -0500 Received: from [10.250.100.73] (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id 175IhebH020200; Thu, 5 Aug 2021 13:43:41 -0500 Subject: Re: [PATCH net v2] net: ethernet: ti: cpsw: fix min eth packet size for non-switch use-cases To: "David S. Miller" , , Jakub Kicinski , Ben Hutchings CC: , Vignesh Raghavendra , , Lokesh Vutla , , Ilias Apalodimas References: <20210805145511.12016-1-grygorii.strashko@ti.com> From: Grygorii Strashko Message-ID: <85769243-daa0-c5c4-f441-6270c4b21cd5@ti.com> Date: Thu, 5 Aug 2021 21:43:39 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210805145511.12016-1-grygorii.strashko@ti.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/08/2021 17:55, Grygorii Strashko wrote: > The CPSW switchdev driver inherited fix from commit 9421c9015047 ("net: > ethernet: ti: cpsw: fix min eth packet size") which changes min TX packet > size to 64bytes (VLAN_ETH_ZLEN, excluding ETH_FCS). It was done to fix HW > packed drop issue when packets are sent from Host to the port with PVID and > un-tagging enabled. Unfortunately this breaks some other non-switch > specific use-cases, like: > - [1] CPSW port as DSA CPU port with DSA-tag applied at the end of the > packet > - [2] Some industrial protocols, which expects min TX packet size 60Bytes > (excluding FCS). > > Fix it by configuring min TX packet size depending on driver mode > - 60Bytes (ETH_ZLEN) for multi mac (dual-mac) mode > - 64Bytes (VLAN_ETH_ZLEN) for switch mode > and update it during driver mode change and annotate with > READ_ONCE()/WRITE_ONCE() as it can be read by napi while writing. > > [1] https://lore.kernel.org/netdev/20210531124051.GA15218@cephalopod/ > [2] https://e2e.ti.com/support/arm/sitara_arm/f/791/t/701669 > > > Cc: stable@vger.kernel.org > Fixes: ed3525eda4c4 ("net: ethernet: ti: introduce cpsw switchdev based driver part 1 - dual-emac") > Reported-by: Ben Hutchings > Signed-off-by: Grygorii Strashko > --- > > Changes in v2: > - use skb_put_padto > - update description > - annotate tx_packet_min with READ_ONCE()/WRITE_ONCE() > > I'm not going to add additional changes in cpdma configuration interface and, > instead, will send patches to convert all cpdma users to use skb_put_padto() and > drop frames padding from cpdma. > > v1: https://patchwork.kernel.org/project/netdevbpf/patch/20210611132732.10690-1-grygorii.strashko@ti.com/ > > drivers/net/ethernet/ti/cpsw_new.c | 7 +++++-- > drivers/net/ethernet/ti/cpsw_priv.h | 4 +++- > 2 files changed, 8 insertions(+), 3 deletions(-) > Cc: Ilias Apalodimas > diff --git a/drivers/net/ethernet/ti/cpsw_new.c b/drivers/net/ethernet/ti/cpsw_new.c > index ae167223e87f..d904f4ca4b37 100644 > --- a/drivers/net/ethernet/ti/cpsw_new.c > +++ b/drivers/net/ethernet/ti/cpsw_new.c > @@ -921,7 +921,7 @@ static netdev_tx_t cpsw_ndo_start_xmit(struct sk_buff *skb, > struct cpdma_chan *txch; > int ret, q_idx; > > - if (skb_padto(skb, CPSW_MIN_PACKET_SIZE)) { > + if (skb_put_padto(skb, READ_ONCE(priv->tx_packet_min))) { > cpsw_err(priv, tx_err, "packet pad failed\n"); > ndev->stats.tx_dropped++; > return NET_XMIT_DROP; > @@ -1101,7 +1101,7 @@ static int cpsw_ndo_xdp_xmit(struct net_device *ndev, int n, > > for (i = 0; i < n; i++) { > xdpf = frames[i]; > - if (xdpf->len < CPSW_MIN_PACKET_SIZE) > + if (xdpf->len < READ_ONCE(priv->tx_packet_min)) > break; > > if (cpsw_xdp_tx_frame(priv, xdpf, NULL, priv->emac_port)) > @@ -1390,6 +1390,7 @@ static int cpsw_create_ports(struct cpsw_common *cpsw) > priv->dev = dev; > priv->msg_enable = netif_msg_init(debug_level, CPSW_DEBUG); > priv->emac_port = i + 1; > + priv->tx_packet_min = CPSW_MIN_PACKET_SIZE; > > if (is_valid_ether_addr(slave_data->mac_addr)) { > ether_addr_copy(priv->mac_addr, slave_data->mac_addr); > @@ -1698,6 +1699,7 @@ static int cpsw_dl_switch_mode_set(struct devlink *dl, u32 id, > > priv = netdev_priv(sl_ndev); > slave->port_vlan = vlan; > + WRITE_ONCE(priv->tx_packet_min, CPSW_MIN_PACKET_SIZE_VLAN); > if (netif_running(sl_ndev)) > cpsw_port_add_switch_def_ale_entries(priv, > slave); > @@ -1726,6 +1728,7 @@ static int cpsw_dl_switch_mode_set(struct devlink *dl, u32 id, > > priv = netdev_priv(slave->ndev); > slave->port_vlan = slave->data->dual_emac_res_vlan; > + WRITE_ONCE(priv->tx_packet_min, CPSW_MIN_PACKET_SIZE); > cpsw_port_add_dual_emac_def_ale_entries(priv, slave); > } > > diff --git a/drivers/net/ethernet/ti/cpsw_priv.h b/drivers/net/ethernet/ti/cpsw_priv.h > index a323bea54faa..2951fb7b9dae 100644 > --- a/drivers/net/ethernet/ti/cpsw_priv.h > +++ b/drivers/net/ethernet/ti/cpsw_priv.h > @@ -89,7 +89,8 @@ do { \ > > #define CPSW_POLL_WEIGHT 64 > #define CPSW_RX_VLAN_ENCAP_HDR_SIZE 4 > -#define CPSW_MIN_PACKET_SIZE (VLAN_ETH_ZLEN) > +#define CPSW_MIN_PACKET_SIZE_VLAN (VLAN_ETH_ZLEN) > +#define CPSW_MIN_PACKET_SIZE (ETH_ZLEN) > #define CPSW_MAX_PACKET_SIZE (VLAN_ETH_FRAME_LEN +\ > ETH_FCS_LEN +\ > CPSW_RX_VLAN_ENCAP_HDR_SIZE) > @@ -380,6 +381,7 @@ struct cpsw_priv { > u32 emac_port; > struct cpsw_common *cpsw; > int offload_fwd_mark; > + u32 tx_packet_min; > }; > > #define ndev_to_cpsw(ndev) (((struct cpsw_priv *)netdev_priv(ndev))->cpsw) > -- Best regards, grygorii