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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 8AE10C43331 for ; Mon, 28 Dec 2020 13:11:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 59363208D5 for ; Mon, 28 Dec 2020 13:11:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731444AbgL1NKn (ORCPT ); Mon, 28 Dec 2020 08:10:43 -0500 Received: from mail.kernel.org ([198.145.29.99]:37570 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729679AbgL1NKk (ORCPT ); Mon, 28 Dec 2020 08:10:40 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5D42422AAA; Mon, 28 Dec 2020 13:10:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609161024; bh=eIeAnZ6izoxXlyAWa6UdwaNo4l0ahH+vpR/Z9cdwvp4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C2YgrOSOufYyrcNXJOgvfvRQVSmj5YlkdcQsEOQsfpXIkPL7SkcDCv1JgBiScUX79 hkY73Z5weoTsk8sJI8DhgmGtBDKrf5m8eusA8igRE8sIRyR7p/4VzDrDARy1sYZsn1 5lM2TeaPOnGQ8o57nEe5KViU15BEOjRyKUsBcalU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Annika Wickert , Sven Eckelmann , Annika Wickert , Jakub Kicinski , Sasha Levin Subject: [PATCH 4.14 044/242] vxlan: Add needed_headroom for lower device Date: Mon, 28 Dec 2020 13:47:29 +0100 Message-Id: <20201228124906.846772470@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228124904.654293249@linuxfoundation.org> References: <20201228124904.654293249@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sven Eckelmann [ Upstream commit 0a35dc41fea67ac4495ce7584406bf9557a6e7d0 ] It was observed that sending data via batadv over vxlan (on top of wireguard) reduced the performance massively compared to raw ethernet or batadv on raw ethernet. A check of perf data showed that the vxlan_build_skb was calling all the time pskb_expand_head to allocate enough headroom for: min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len + VXLAN_HLEN + iphdr_len; But the vxlan_config_apply only requested needed headroom for: lowerdev->hard_header_len + VXLAN6_HEADROOM or VXLAN_HEADROOM So it completely ignored the needed_headroom of the lower device. The first caller of net_dev_xmit could therefore never make sure that enough headroom was allocated for the rest of the transmit path. Cc: Annika Wickert Signed-off-by: Sven Eckelmann Tested-by: Annika Wickert Link: https://lore.kernel.org/r/20201126125247.1047977-1-sven@narfation.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/vxlan.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 82efa5bbf568b..c21f28840f05b 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -3184,6 +3184,7 @@ static void vxlan_config_apply(struct net_device *dev, dev->gso_max_segs = lowerdev->gso_max_segs; needed_headroom = lowerdev->hard_header_len; + needed_headroom += lowerdev->needed_headroom; max_mtu = lowerdev->mtu - (use_ipv6 ? VXLAN6_HEADROOM : VXLAN_HEADROOM); -- 2.27.0