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=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 EC204C5CFEB for ; Mon, 9 Jul 2018 19:20:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B2BC620881 for ; Mon, 9 Jul 2018 19:20:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B2BC620881 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754694AbeGITUK (ORCPT ); Mon, 9 Jul 2018 15:20:10 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:41710 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754521AbeGITUJ (ORCPT ); Mon, 9 Jul 2018 15:20:09 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A1D3F7D84D; Mon, 9 Jul 2018 19:20:08 +0000 (UTC) Received: from localhost (ovpn-200-25.brq.redhat.com [10.40.200.25]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1FACD1C596; Mon, 9 Jul 2018 19:20:04 +0000 (UTC) Date: Mon, 9 Jul 2018 21:20:03 +0200 From: Jesper Dangaard Brouer To: Taeung Song Cc: Alexei Starovoitov , Daniel Borkmann , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, brouer@redhat.com Subject: Re: [PATCH] samples/bpf: Fix tc and ip path in xdp2skb_meta.sh Message-ID: <20180709212003.10b8e490@redhat.com> In-Reply-To: <30be797e-e247-1b34-6607-0f0fd3b898fd@gmail.com> References: <20180709150418.32034-1-treeze.taeung@gmail.com> <20180709174029.3c05e750@redhat.com> <30be797e-e247-1b34-6607-0f0fd3b898fd@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Mon, 09 Jul 2018 19:20:08 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Mon, 09 Jul 2018 19:20:08 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'brouer@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 10 Jul 2018 02:44:06 +0900 Taeung Song wrote: > Hi Jesper Dangaard Brouer, > > On 07/10/2018 12:40 AM, Jesper Dangaard Brouer wrote: > > On Tue, 10 Jul 2018 00:04:18 +0900 > > Taeung Song wrote: > > > >> The below path error can occur: > >> > >> # ./xdp2skb_meta.sh --dev eth0 --list > >> ./xdp2skb_meta.sh: line 61: /usr/sbin/tc: No such file or directory > >> > >> # which tc > >> /sbin/tc > >> > >> So use 'which' command instead of absolute path of tc and ip > >> > >> Fixes: 36e04a2d78d9 ("samples/bpf: xdp2skb_meta shows transferring info from XDP to SKB") > >> Cc: Jesper Dangaard Brouer > >> Signed-off-by: Taeung Song > >> --- > >> samples/bpf/xdp2skb_meta.sh | 4 ++-- > >> 1 file changed, 2 insertions(+), 2 deletions(-) > >> > >> diff --git a/samples/bpf/xdp2skb_meta.sh b/samples/bpf/xdp2skb_meta.sh > >> index b9c9549c4c27..67cf7b5f336d 100755 > >> --- a/samples/bpf/xdp2skb_meta.sh > >> +++ b/samples/bpf/xdp2skb_meta.sh > >> @@ -16,8 +16,8 @@ > >> BPF_FILE=xdp2skb_meta_kern.o > >> DIR=$(dirname $0) > >> > >> -export TC=/usr/sbin/tc > >> -export IP=/usr/sbin/ip > >> +export TC=`which tc` > >> +export IP=`which ip` > > > > This is not a good solution, as 'which' can return something else. > > E.g. on my system I've aliased 'tc' to 'sudo tc', and `which tc` returns: > > > > $ which tc > > alias tc='sudo tc' > > /usr/bin/sudo > > > > The easiest solution is to simply do: > > > > export TC=tc > > export IP=ip > > > > The more fancy solution is to allow callers to redefine $IP and $TC: > > > > [ -z "$TC" ] && TC=tc > > [ -z "$IP" ] && IP=ip > > > > Yep, you are right, I'll change it. > > > And then you should also fix the use of 'basename', see below patch... > > > > I thought it'd be fine to leave 'basename' as it is, > because if callers redefine TC=/home/taeung/tc and give > the options --verbose or --dry-run, 'basename' can more tidily show outputs. The 'basename' does not work correctly if e.g. TC='sudo tc'. Below output is with 'basename' removed, else it would say "sudo qdisc del ..." TC='sudo tc' IP='sudo ip' ./xdp2skb_meta.sh -v --dev mlx5p1 --dry-run # Device set to: DEV=mlx5p1 # Dry-run mode: enable VERBOSE and don't call TC+IP sudo tc qdisc del dev mlx5p1 clsact sudo tc qdisc add dev mlx5p1 clsact sudo tc filter add dev mlx5p1 ingress prio 1 handle 1 bpf da obj ./xdp2skb_meta_kern.o sec tc_mark # Flush XDP on device: mlx5p1 sudo ip link set dev mlx5p1 xdp off sudo ip link set dev mlx5p1 xdp obj ./xdp2skb_meta_kern.o sec xdp_mark > But it seems to be trivial, I'll resend this patch as v2 based on your > comment ! Thx, already ACKed it :-) -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer