From mboxrd@z Thu Jan 1 00:00:00 1970 From: Duan Jiong Subject: Re: [PATCH] ipv6: remove the unnecessary statement in find_match() Date: Thu, 31 Oct 2013 19:09:56 +0800 Message-ID: <52723A84.9080308@cn.fujitsu.com> References: <5270B7AE.9020801@cn.fujitsu.com> <20131030.170837.1882918923249091614.davem@davemloft.net> <20131030211157.GA13902@order.stressinduktion.org> <20131031.002234.45924350853188128.davem@davemloft.net> <5271F263.4020800@cn.fujitsu.com> <20131031084537.GA17210@order.stressinduktion.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org, hannes@stressinduktion.org To: David Miller Return-path: Received: from cn.fujitsu.com ([222.73.24.84]:14148 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752053Ab3JaLOy convert rfc822-to-8bit (ORCPT ); Thu, 31 Oct 2013 07:14:54 -0400 In-Reply-To: <20131031084537.GA17210@order.stressinduktion.org> Sender: netdev-owner@vger.kernel.org List-ID: =E4=BA=8E 2013=E5=B9=B410=E6=9C=8831=E6=97=A5 16:45, Hannes Frederic So= wa =E5=86=99=E9=81=93: > On Thu, Oct 31, 2013 at 02:02:11PM +0800, Duan Jiong wrote: >> =E4=BA=8E 2013=E5=B9=B410=E6=9C=8831=E6=97=A5 12:22, David Miller =E5= =86=99=E9=81=93: >>> From: Hannes Frederic Sowa >>> Date: Wed, 30 Oct 2013 22:11:57 +0100 >>> >>>> On Wed, Oct 30, 2013 at 05:08:37PM -0400, David Miller wrote: >>>>> From: Duan Jiong >>>>> Date: Wed, 30 Oct 2013 15:39:26 +0800 >>>>> >>>>>> >>>>>> After reading the function rt6_check_neigh(), we can >>>>>> know that the RT6_NUD_FAIL_SOFT can be returned only >>>>>> when the IS_ENABLE(CONFIG_IPV6_ROUTER_PREF) is false. >>>>>> so in function find_match(), there is no need to execute >>>>>> the statement !IS_ENABLED(CONFIG_IPV6_ROUTER_PREF). >>>>>> >>>>>> Signed-off-by: Duan Jiong >>>>> >>>>> Applied to net-next, thanks. >>>>> >>>>> CONFIG_IPV6_ROUTER_PREF is another good candidate for Kconfig >>>>> removal. I know we've had several bugs that only apply when >>>>> this option is on vs. off. We're maintaining two different >>>>> code paths, for really no good reason. >>>> >>>> I agree and actually thought about that yesterday. Do you think a = sysctl >>>> is a good option? >>> >>> Every distribution ships with the Kconfig option on, and no sysctl >>> exists currently to control it. >>> >>> So I'd say it's not necessary at all, or at the very least let's ha= ve >>> someone come forward with a real rather than theoretical use case f= or >>> such a feature before adding it. >>> >>> Actually, if RFC 4191 has the usual language like "there SHOULD be >>> an administrative mechanism to disable blah blah blah" I could >>> be convinced to add it now. Can someone take a look? >> >> It seems that there is no such an administrative mechanism in RFC 41= 91. >> >> By the way, if the sysctl is used, we are still maintaining two diff= erent >> code paths, isn't it? so i think David's idea is good. >=20 > Makes life easier, no objections from me. >=20 Removing CONFIG_IPV6_ROUTER_PREF means that the Router Preference is al= ways on, is this understanding right? If that's is correct, i think compatibility issues will arise. For exa= mple, when the CONFIG_IPV6_ROUTER_PREF option is on, the kernel should not do round-ro= bin during default router selection, but when the CONFIG_IPV6_ROUTER_PREF option i= s off, the kernel should do it. Thanks, Duan > Greetings, >=20 > Hannes >=20 > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >=20