From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jamal Hadi Salim Subject: Re: [PATCH net-next v4] rps: selective flow shedding during softnet overflow Date: Tue, 23 Apr 2013 21:44:37 -0400 Message-ID: <51773905.9030005@mojatatu.com> References: <1366749094-5982-1-git-send-email-willemb@google.com> <20130423142333.15479dfa@nehalam.linuxnetplumber.net> <1366753063.8964.14.camel@edumazet-glaptop> <20130423145222.5b696d0c@nehalam.linuxnetplumber.net> <1366762196.8964.46.camel@edumazet-glaptop> <517734A2.9060609@mojatatu.com> <1366767151.8964.56.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="------------010306020506090507080302" Cc: Stephen Hemminger , Willem de Bruijn , netdev@vger.kernel.org, davem@davemloft.net To: Eric Dumazet Return-path: Received: from mail-ob0-f173.google.com ([209.85.214.173]:41784 "EHLO mail-ob0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754902Ab3DXBok (ORCPT ); Tue, 23 Apr 2013 21:44:40 -0400 Received: by mail-ob0-f173.google.com with SMTP id xn12so1045213obc.4 for ; Tue, 23 Apr 2013 18:44:40 -0700 (PDT) In-Reply-To: <1366767151.8964.56.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: This is a multi-part message in MIME format. --------------010306020506090507080302 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 13-04-23 09:32 PM, Eric Dumazet wrote: > On Tue, 2013-04-23 at 21:25 -0400, Jamal Hadi Salim wrote: > Not sure what you mean. The qdisc stuff would replace the 'cpu backlog', Aha ;-> So you would have many little backlogs one per ring per cpu, correct? > not be added to it. Think of having possibility to control backlog using > standard qdiscs, like fq_codel ;) Excellent. So this is not as a big surgery as it sounds then. the backloglets just need to be exposed as netdevs. > Yes, but the per cpu backlog is shared for all devices. We probably want > different qdisc for gre tunnel, eth0, ... Makes sense. BTW, looking at __skb_get_rxhash(), if i had a driver that sets either skb->rxhash (picks it off the dma descriptor), could i not use that instead of computing the hash? something like attached patch. cheers, jamal --------------010306020506090507080302 Content-Type: text/plain; charset=UTF-8; name="p1" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="p1" ZGlmZiAtLWdpdCBhL25ldC9jb3JlL2Zsb3dfZGlzc2VjdG9yLmMgYi9uZXQvY29yZS9mbG93 X2Rpc3NlY3Rvci5jCmluZGV4IGUxODdiZjAuLmE2YWJlZTAgMTAwNjQ0Ci0tLSBhL25ldC9j b3JlL2Zsb3dfZGlzc2VjdG9yLmMKKysrIGIvbmV0L2NvcmUvZmxvd19kaXNzZWN0b3IuYwpA QCAtMTU5LDggKzE1OSw5IEBAIHZvaWQgX19za2JfZ2V0X3J4aGFzaChzdHJ1Y3Qgc2tfYnVm ZiAqc2tiKQogCXN0cnVjdCBmbG93X2tleXMga2V5czsKIAl1MzIgaGFzaDsKIAotCWlmICgh c2tiX2Zsb3dfZGlzc2VjdChza2IsICZrZXlzKSkKKwlpZiAoc2tiLT5yeGhhc2ggfHwgIXNr Yl9mbG93X2Rpc3NlY3Qoc2tiLCAma2V5cykpIHsKIAkJcmV0dXJuOworCX0KIAogCWlmIChr ZXlzLnBvcnRzKQogCQlza2ItPmw0X3J4aGFzaCA9IDE7Cg== --------------010306020506090507080302--