From mboxrd@z Thu Jan 1 00:00:00 1970 From: Changli Gao Subject: Re: [PATCH v5] rps: Receive Packet Steering Date: Fri, 15 Jan 2010 17:20:43 +0800 Message-ID: <412e6f7f1001150120r622450eem2d9f54da27c42fba@mail.gmail.com> References: <4B5008F5.6090007@gmail.com> <412e6f7f1001142239n704d2827q614f59255e85e328@mail.gmail.com> <4B5011F4.8010204@gmail.com> <20100115.004915.64525965.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: eric.dumazet@gmail.com, therbert@google.com, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org To: David Miller Return-path: Received: from fg-out-1718.google.com ([72.14.220.158]:53268 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753394Ab0AOJUp convert rfc822-to-8bit (ORCPT ); Fri, 15 Jan 2010 04:20:45 -0500 In-Reply-To: <20100115.004915.64525965.davem@davemloft.net> Sender: netfilter-devel-owner@vger.kernel.org List-ID: On Fri, Jan 15, 2010 at 4:49 PM, David Miller wro= te: > > Actually, no thanks. =C2=A0Have you actually taken a look at > ipv6_skip_exthdr()? > > Do that, then tell me that you want the extra function call, plus all > of the processing and data touching that that function does, just to > handle the case that there "might" be ipv6 extension headers there. > I don't think ipv6_skip_exthdr() is too weight. If there isn't any extra header, only some compare and jump instruments are added, and no more data references. If there are some headers, I think distributing packets among CPUs is more important than the extra cost introduced by calling ipv6_skip_exthdr(). > It is the exception rather than the rule, and I think it's just > assume we have a real protocol header next. > > And that's what skb_tx_hash() used to do too before we started using > the recorded RX queue and socket hash values. > > Nobody cared and nobody complained. =C2=A0Guess why? =C2=A0Because in= practice > it doesn't matter. > Maybe they don't know it.If it was a performance regression, I think more people might pay attention on it. --=20 Regards=EF=BC=8C Changli Gao(xiaosuo@gmail.com) -- To unsubscribe from this list: send the line "unsubscribe netfilter-dev= el" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html