From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: Re: [net-next PATCH v3 1/3] net: sched: consolidate offload decision in cls_u32 Date: Mon, 29 Feb 2016 15:40:26 -0800 Message-ID: <56D4D6EA.50608@gmail.com> References: <20160226154858.5338.90569.stgit@john-Precision-Tower-5810> <20160226155349.5338.74615.stgit@john-Precision-Tower-5810> <56D124F1.3070300@gmail.com> <56D490B5.5060302@gmail.com> <20160229185812.GA2121@nanopsycho.orion> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: Daniel Borkmann , simon.horman@netronome.com, Linux Kernel Network Developers , Alexei Starovoitov , David Miller , Jamal Hadi Salim To: Cong Wang , Jiri Pirko Return-path: Received: from mail-pa0-f41.google.com ([209.85.220.41]:34597 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750832AbcB2Xkk (ORCPT ); Mon, 29 Feb 2016 18:40:40 -0500 Received: by mail-pa0-f41.google.com with SMTP id fy10so100096524pac.1 for ; Mon, 29 Feb 2016 15:40:40 -0800 (PST) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 16-02-29 01:25 PM, Cong Wang wrote: > On Mon, Feb 29, 2016 at 10:58 AM, Jiri Pirko wrote: >> Mon, Feb 29, 2016 at 07:40:53PM CET, john.fastabend@gmail.com wrote: >>> On 16-02-27 08:28 PM, Cong Wang wrote: >>>> On Fri, Feb 26, 2016 at 8:24 PM, John Fastabend >>>> wrote: >>>>> On 16-02-26 09:39 AM, Cong Wang wrote: >>>>>> On Fri, Feb 26, 2016 at 7:53 AM, John Fastabend >>>>>> wrote: >>>>>>> diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h >>>>>>> index 2121df5..e64d20b 100644 >>>>>>> --- a/include/net/pkt_cls.h >>>>>>> +++ b/include/net/pkt_cls.h >>>>>>> @@ -392,4 +392,9 @@ struct tc_cls_u32_offload { >>>>>>> }; >>>>>>> }; >>>>>>> >>>>>>> +static inline bool tc_should_offload(struct net_device *dev) >>>>>>> +{ >>>>>>> + return dev->netdev_ops->ndo_setup_tc; >>>>>>> +} >>>>>>> + >>>>>> >>>>>> These should be protected by CONFIG_NET_CLS_U32, no? >>>>>> >>>>> >>>>> Its not necessary it is a completely general function and I only >>>>> lifted it out of cls_u32 so that the cls_flower classifier could >>>>> also use it. >>>>> >>>>> I don't see the need off-hand to have it wrapped in an ORd ifdef >>>>> statement where its (CONFIG_NET_CLS_U32 | CONFIG_NET_CLS_X ...). >>>>> Any particular reason you were thnking it should be wrapped in ifdefs? >>>>> >>>> >>>> Not a big deal. >>>> >>>> I just feel these don't need to compile when I have CONFIG_NET_CLS_U32=n. >>>> >>>> Thanks. >>>> >>> >>> Well because this is 'static inline' gcc should just remove it >>> if it is not used. Assuming non-ancient gcc and normal compile >>> flags, e.g. you are not including -fkeep-inline-functions or >>> something. >>> >>> So just to keep it readable I would prefer to just leave it >>> as is. >> >> Definitelly. cls_flower will use it in very near future. Making it >> dependent on CONFIG_NET_CLS_U32 makes 0 sense to me. > > Oh, why then do you have u32 in the struct name tc_cls_u32_offload? > > (Note that in the above I said "these" not "this", so I never only refer > to tc_should_offload) > hmm yeah that likely wont be needed by flower although it could be used. I still think its best to leave this as is there doesn't seem to be a very strong precedent to wrap any of the other structs/fields/etc in pkt_cls.h into their respective ifdef/endif blocks. And I think it starts to get a bit much if we do. I'm trusting gcc here can do the right thing when these are included but never used. Thanks, John