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=-8.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 EECC4C2D0A3 for ; Mon, 2 Nov 2020 20:54:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8D428206D8 for ; Mon, 2 Nov 2020 20:54:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="FYV9DxEe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727116AbgKBUyd (ORCPT ); Mon, 2 Nov 2020 15:54:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726447AbgKBUwc (ORCPT ); Mon, 2 Nov 2020 15:52:32 -0500 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C024EC0617A6 for ; Mon, 2 Nov 2020 12:52:30 -0800 (PST) Received: by mail-pf1-x441.google.com with SMTP id w65so12217310pfd.3 for ; Mon, 02 Nov 2020 12:52:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=ZwEoERCM5ujoro0z9B5jHtM/h0u16bE0c9lNBDoMQGo=; b=FYV9DxEe3LESDsPWIJyej96C1k9vpyc48tLQPGjIJLlrjRBxO0eHHs427SSx3nfy+f v46hRGb771C1Zdx2FrxkxB2S6OFXoVvh8mhCwQuAEEFgH49yPzzo9stj6K4VRmPZztwt wPET9HNDVPgz3ZZKomMHMm8H+fvriot2qbPliZ8gJwU0zAqkaO/nHQDTfl8S1w8Sj/XC tlD17BoObOlJXsR8QoBNxnUfuavkuR3QvFyk5gPN3ygxOy17WZL5T20U1kGN7JQ+rc8O HOZ5uKwBLuBoazdomDW4NGVR4dya/tEGqtGBXZMR4/Lmy9wJkOYSlGMAJl7exlJzhATv sI4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=ZwEoERCM5ujoro0z9B5jHtM/h0u16bE0c9lNBDoMQGo=; b=dObd/sOKJ338UpviySAtv0EfdSmUZ+xoqCZopZpW8S4mIz5rKIcjuwz4931BBXVg94 dkbPVC/nVCeYMXUm7IWhAwI43KGD9Uh1HgrdeW6B92kLSvQMYKBxpu0W+EAzj4U+o1Tw Zzk7duLYD3n0jjynaeo9m/5NEofdd/sAVtEUAPpoFSuvuU1iSMw/rOmeRhVHyeOIqR2F OtL3/ezHIV0glSDaBhHPvVvpvBUoVVIiZ+juUCTt5l+XFlxwXSyQhrnGJ2EFGLuLNBDa dCTRzwFaSt1eNqJ5xIxKTgOAGukWvZUXqrRxRZvM47WQIvRZYrBWvadTnyeeTIbKevoS Np4g== X-Gm-Message-State: AOAM533SQz0jUBvj0WBtNWrk0sshIFBvpwYgFxGY8H4iXt+o2ng+y0X7 eNBbIYB5e8qeKAgNfNRYYVo= X-Google-Smtp-Source: ABdhPJz+La6CPkU93A459wh+FPV7MXp+3zVcSQom8RGKeBFpSb258BeEVsOxff63VZRqsGk7kOv27g== X-Received: by 2002:a17:90b:994:: with SMTP id bl20mr38848pjb.34.1604350350327; Mon, 02 Nov 2020 12:52:30 -0800 (PST) Received: from [10.230.28.234] ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id jy19sm392713pjb.9.2020.11.02.12.52.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 02 Nov 2020 12:52:29 -0800 (PST) Subject: Re: [PATCH v3 net-next 11/12] net: dsa: tag_gswip: let DSA core deal with TX reallocation To: Vladimir Oltean , netdev@vger.kernel.org Cc: andrew@lunn.ch, vivien.didelot@gmail.com, kuba@kernel.org, Christian Eggers , Kurt Kanzenbach , Hauke Mehrtens References: <20201101191620.589272-1-vladimir.oltean@nxp.com> <20201101191620.589272-12-vladimir.oltean@nxp.com> From: Florian Fainelli Message-ID: <8fe096a9-6d30-5e54-39b5-b371ed00d1f7@gmail.com> Date: Mon, 2 Nov 2020 12:52:27 -0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Firefox/78.0 Thunderbird/78.4.0 MIME-Version: 1.0 In-Reply-To: <20201101191620.589272-12-vladimir.oltean@nxp.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 11/1/2020 11:16 AM, Vladimir Oltean wrote: > Now that we have a central TX reallocation procedure that accounts for > the tagger's needed headroom in a generic way, we can remove the > skb_cow_head call. > > This one is interesting, the DSA tag is 8 bytes on RX and 4 bytes on TX. > Because DSA is unaware of asymmetrical tag lengths, the overhead/needed > headroom is declared as 8 bytes and therefore 4 bytes larger than it > needs to be. If this becomes a problem, and the GSWIP driver can't be > converted to a uniform header length, we might need to make DSA aware of > separate RX/TX overhead values. > > Cc: Hauke Mehrtens > Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli -- Florian