From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: TUN device performance regression Date: Mon, 14 Apr 2014 10:43:14 -0400 Message-ID: <534BF402.6010505@gmail.com> References: <1397475118.11864.5.camel@interceptor.in.smoula.net> <1397475759.12568.0.camel@interceptor.in.smoula.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit To: Martin Filip , netdev@vger.kernel.org Return-path: Received: from mail-qa0-f41.google.com ([209.85.216.41]:51142 "EHLO mail-qa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754994AbaDNOnR (ORCPT ); Mon, 14 Apr 2014 10:43:17 -0400 Received: by mail-qa0-f41.google.com with SMTP id j5so8187235qaq.28 for ; Mon, 14 Apr 2014 07:43:17 -0700 (PDT) In-Reply-To: <1397475759.12568.0.camel@interceptor.in.smoula.net> Sender: netdev-owner@vger.kernel.org List-ID: On 04/14/2014 07:42 AM, Martin Filip wrote: >> Hello, >> >> I've noticed significant TUN device performance drop between 3.13 and >> 3.14 kernels, problem seems to persist until current git version. >> >> With good kernel I can achieve full 100mbps through openvpn without any >> problem, with problematic kernel TX performance drops down to ~50kbps. >> >> According to git bisect it seems that root of all evil is commit >> 53d6471cef17262d3ad1c7ce8982a234244f68ec. >> >> I can confirm that performance is great again with current kernel when I >> revert this one. >> > I've forgot to mention kernel bug: > https://bugzilla.kernel.org/show_bug.cgi?id=74051 > Could you please try this patch. --- net/core/dev.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 45fa2f1..6088927 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -2289,7 +2289,7 @@ EXPORT_SYMBOL(skb_checksum_help); __be16 skb_network_protocol(struct sk_buff *skb, int *depth) { __be16 type = skb->protocol; - int vlan_depth = ETH_HLEN; + int vlan_depth = skb->mac_len; /* Tunnel gso handlers can set protocol to ethernet. */ if (type == htons(ETH_P_TEB)) {