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 201DEC433DB for ; Mon, 28 Dec 2020 13:41:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E3A36207B2 for ; Mon, 28 Dec 2020 13:41:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404017AbgL1Nlk (ORCPT ); Mon, 28 Dec 2020 08:41:40 -0500 Received: from mail.kernel.org ([198.145.29.99]:41182 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391511AbgL1NlA (ORCPT ); Mon, 28 Dec 2020 08:41:00 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8F4CC22A84; Mon, 28 Dec 2020 13:40:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609162819; bh=jlsM12PnKPXZL1Ky68Ox9ha9r6zBCa6jDqNLVuiki0k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WLPRAfj/Homk2beFZHmW+/Tx5Zk6cWn0CqCkYSgo1ushswpbuXw+xvE/YT8NWa/s7 /E0TrbnQxwPgAzRZAnFt2pwCSw0ouRxgKqGufvsV7xSQ/FRYulcddq99EzI9+EvDBn Vm/C+eVmAU6/nEaYX6afp9sgeU7ZI56RAS6Y+XAY= 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 5.4 042/453] vxlan: Add needed_headroom for lower device Date: Mon, 28 Dec 2020 13:44:38 +0100 Message-Id: <20201228124939.284399062@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228124937.240114599@linuxfoundation.org> References: <20201228124937.240114599@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 630ac00a34ede..3753cf0942865 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -3538,6 +3538,7 @@ 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