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=-0.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 ED9B7C1B08C for ; Thu, 15 Jul 2021 13:04:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D9EDE613C1 for ; Thu, 15 Jul 2021 13:04:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235623AbhGONHg (ORCPT ); Thu, 15 Jul 2021 09:07:36 -0400 Received: from mout.gmx.net ([212.227.17.22]:45775 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229624AbhGONHf (ORCPT ); Thu, 15 Jul 2021 09:07:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1626354271; bh=3XKnCVe17/cL/PJQD7dAeEz7KGEt/61iS/itcmUBvTw=; h=X-UI-Sender-Class:From:To:Cc:Subject:Date:In-Reply-To:References; b=AehGIjIFryTdfYB6UGcGPOqsSWwkRDhvA9wnNHEX9IOamuDhN9gc7QCCvMHE3Zd3s Dz/OxXYKsuqzGYVqn7kCXssY9XIOI4bOtkOcm6uG8weCe6muMWB/EBU2o2A4hilAkj VgNjkq/IwYAWMFVoXPWu8vU1sIZCpm47eGQqPuno= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [87.130.101.138] ([87.130.101.138]) by web-mail.gmx.net (3c-app-gmx-bap31.server.lan [172.19.172.101]) (via HTTP); Thu, 15 Jul 2021 15:04:31 +0200 MIME-Version: 1.0 Message-ID: From: Lino Sanfilippo To: Vladimir Oltean Cc: Andrew Lunn , woojung.huh@microchip.com, UNGLinuxDriver@microchip.com, vivien.didelot@gmail.com, f.fainelli@gmail.com, davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Aw: Re: [PATCH 2/2] net: dsa: tag_ksz: dont let the hardware process the layer 4 checksum Content-Type: text/plain; charset=UTF-8 Date: Thu, 15 Jul 2021 15:04:31 +0200 Importance: normal Sensitivity: Normal In-Reply-To: <20210715114908.ripblpevmdujkf2m@skbuf> References: <20210714191723.31294-1-LinoSanfilippo@gmx.de> <20210714191723.31294-3-LinoSanfilippo@gmx.de> <20210714194812.stay3oqyw3ogshhj@skbuf> <20210715065455.7nu7zgle2haa6wku@skbuf> <20210715114908.ripblpevmdujkf2m@skbuf> X-UI-Message-Type: mail X-Priority: 3 X-Provags-ID: V03:K1:BSfJAEMGWpjmadghZep1FdQXRxpw04ktpiPXQm4UEOWb2hn8UaCaD6/RHVTWWsP9vxrgu 6KOGEfPGPo7MRxTIC+sfYhjtkA9IEFAVzHKA06WD9cicrV55JhssXal3b7xvyu/MUSyd+ITHCZiO EB+xYMQLNp6CKwx7r9A57F5RYfiCoaZQETxVKzLC81uM93bUUUMxRh1aVKGvEX+F/WSMZil7dg3J 4OXOXly6RXBdsXD+9RvwjnL2tjWxLJC/dovEuIrMP0PFeWj1EhdkybWPBJQvNKF0jhjA5CFSkqsA dg= X-UI-Out-Filterresults: notjunk:1;V03:K0:3Ad/TgTgTrE=:KMdnEyIsLgBVyIkXwHnnZQ bykJuNOiF6M8cmKG49845vHTRtMeIbThHhNNfLNDnjlMj3Eei6r8scvlGZaC8EPAfBLuE3ht/ PzEuOX4giqxS+zc4hL6YYP8XAzf2EzBgIy0vpNZaoNE0foMzYvdwtas1FTFDfVnbv0F1G9bCP /HtdoOsJ0H3U8VghjPrPOkBGvzllW1ii59I95Lmrs1nztOM50NVbJmYW0cnfKfZQa840x1zjH P0omxUqhT72A9sw6yRMAcx0YazzUIl6p0ZgWV/YmW/NUr3aYl3kE/uk450ZRkjJQavc9bSc4g hsv8nVQ3ozNTvNCh9bILkd8kE8FgoxVi8T8atnUIVLmcjNdY0SpI8qSR9pWr+jYgA/GaKrSEf gVE3vEGhqU40FJwxXMG101qR1j1xETsuSb7Zx30rzBJdQ0bgeULqdknrHYIYbILeRQrgtB22a TMHVrACpewIYGaTfAxYurxGc204JddUOWzq6yzoXD1VCESeG17Ty++wGrQBLnOBX7UfRIuUSe 1c4HZ/bWNAKkuAFmIqwZGZmGZWcVe6N9QTaDJaRrKU7YPZ7fU9ZUB+xl+xmdZTky5d9FaOYNg +is3FIp7XOMnFiUEdBdZ0y2cYFuEiGctEcDaJn9LQLViK2G00B8bgolG7tbxmBlGlow9utteJ 4iBrGjGACCXtgnypUGmPJKqIBZmf5AjID8jY0HRzlC4QsxwYHsw25VflS1h8cGfPmU7GW/8tq TmwSuk0jN7QRPSFf4pj9UOPYwwYlvooFV0M4KkGCaQMNSdn4M3ZfWwtYa3Gn++TweR+NWlF+F x7jqYzpSHmI80LLv7/GW9WHUVZDWzTO6qcyw/X/+6MN8MEbnAA= Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Gesendet: Donnerstag, 15. Juli 2021 um 13:49 Uhr > Von: "Vladimir Oltean" > An: "Lino Sanfilippo" > Cc: "Andrew Lunn" , woojung.huh@microchip.com, UNGLinuxD= river@microchip.com, vivien.didelot@gmail.com, f.fainelli@gmail.com, davem= @davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger= .kernel.org > Betreff: Re: [PATCH 2/2] net: dsa: tag_ksz: dont let the hardware proces= s the layer 4 checksum > > On Thu, Jul 15, 2021 at 01:16:12PM +0200, Lino Sanfilippo wrote: > > Sure, I will test this solution. But I think NETIF_F_FRAGLIST should a= lso be > > cleared in this case, right? > > Hmm, interesting question. I think only hns3 makes meaningful use of > NETIF_F_FRAGLIST, right? I'm looking at hns3_fill_skb_to_desc(). > Other drivers seem to set it for ridiculous reasons - looking at commit > 66aa0678efc2 ("ibmveth: Support to enable LSO/CSO for Trunk VEA.") - > they set NETIF_F_FRAGLIST and then linearize the skb chain anyway. The > claimed 4x throughput benefit probably has to do with less skbs > traversing the stack? I don't know. > > Anyway, it is hard to imagine all the things that could go wrong with > chains of IP fragments on a DSA interface, precisely because I have so > few examples to look at. I would say, header taggers are probably fine, > tail taggers not so much, so apply the same treatment as for NETIF_F_SG? > Please note that skb_put() asserts that the SKB is linearized. So I think = we should rather clear both NETIF_F_FRAGLIST and NETIF_F_SG unconditionally s= ince also header taggers use some form of skb_put() dont they?