From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Pirko Subject: Re: [patch iproute2 v2 repost 3/3] tc/actions: introduce support for goto chain action Date: Fri, 2 Jun 2017 10:15:12 +0200 Message-ID: <20170602081512.GB2015@nanopsycho.orion> References: <20170516172802.1317-1-jiri@resnulli.us> <20170516172937.1391-3-jiri@resnulli.us> <20170531142702.6d0ca6fa@griffin> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, davem@davemloft.net, jhs@mojatatu.com, xiyou.wangcong@gmail.com, dsa@cumulusnetworks.com, edumazet@google.com, stephen@networkplumber.org, daniel@iogearbox.net, alexander.h.duyck@intel.com, simon.horman@netronome.com, mlxsw@mellanox.com To: Jiri Benc Return-path: Received: from mail-wm0-f68.google.com ([74.125.82.68]:34674 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750826AbdFBIPP (ORCPT ); Fri, 2 Jun 2017 04:15:15 -0400 Received: by mail-wm0-f68.google.com with SMTP id d127so17022608wmf.1 for ; Fri, 02 Jun 2017 01:15:14 -0700 (PDT) Content-Disposition: inline In-Reply-To: <20170531142702.6d0ca6fa@griffin> Sender: netdev-owner@vger.kernel.org List-ID: Wed, May 31, 2017 at 02:27:02PM CEST, jbenc@redhat.com wrote: >On Tue, 16 May 2017 19:29:37 +0200, Jiri Pirko wrote: >> From: Jiri Pirko >> >> Allow user to set control action "goto" with filter chain index as >> a parameter. >> >> Signed-off-by: Jiri Pirko >> --- >> include/linux/pkt_cls.h | 16 +++++++++++++++- >> man/man8/tc-ife.8 | 2 +- >> man/man8/tc-pedit.8 | 2 +- >> man/man8/tc-police.8 | 2 +- >> man/man8/tc-vlan.8 | 2 +- > >Jiri, this *seriously* needs a proper documentation. I consider myself >to be well above average in understanding tc filters and actions, and as >you know I participated at least passively in some chats about the >chains. Yet I'm still very lost in semantics of chains. I cannot >imagine how an average user would be able to use this. > >Some questions about the semantics: > >- What chain(s) are processed by default? If I don't use goto_chain but > have multiple chains, will only chain 0 be processed, or more? In > what order, what are the rules? If I don't have a chain 0, what would > happen? 0 only. I exepcter it makes sense. But you are right, I will put it to man. > >- What is the relation between priorities and chains? I expected that > chains are under the same priority but that's not the case in your > example. For a user, it's very unclear why there are priorities and > chains. They appear to do the same thing, why can't I just jump > between priorities? Basically, what we had previously was single chain (0) only. Now we have multichain, each chain is completely independent list of tps, each tp having its prio. I will also add this to man. > >Please, in addition to explaining here on the list, add detailed >explanation to the man pages. > >Thanks, > > Jiri