From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 09F29C10F27 for ; Tue, 10 Mar 2020 15:27:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CF2D420578 for ; Tue, 10 Mar 2020 15:27:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WCjs9HdE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727320AbgCJP16 (ORCPT ); Tue, 10 Mar 2020 11:27:58 -0400 Received: from mail-qt1-f174.google.com ([209.85.160.174]:37962 "EHLO mail-qt1-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726451AbgCJP15 (ORCPT ); Tue, 10 Mar 2020 11:27:57 -0400 Received: by mail-qt1-f174.google.com with SMTP id e20so9945053qto.5 for ; Tue, 10 Mar 2020 08:27:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=IgrTYteBKTbEmOfaI7gCgsUk4gIf0PC9kOfOWYsikcw=; b=WCjs9HdE7hsQSl4+kXOFKDADFzCFOkU4JSwFJ9HSEx6pyT/m/CkgbZ9fpCA/jknzWW 3MmSUchVKFqtPyQ0oc482bJcND3X9Vmr/azqsRzM8VeWshkvhv8jrJJpOoxXljOITwSJ Dk6FCKtEjs4GKzvZyVE1cC1ZCJG6R1rxy0n3f3HAot131mct+jST3HIDrkWDsmqykBGw sAr8I7XXK2+EbjXfQQ0is2p5INUNXE8pBUqvCjLfR0WWv/lVF1ioXnUVPGXcJvQJizmU JSFZOVGjVzBmJWCj4hNIcYesIPu5j7LE8qo8+5yi/Kjqec7FqD/PUEEHxw7fqmesSin7 HOOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=IgrTYteBKTbEmOfaI7gCgsUk4gIf0PC9kOfOWYsikcw=; b=N1tGI3UQHJ7rB54YTT2gMFN7DTDaJyNZBTCOvmgllTEUMhw6R3D18pnaameeCiZM7/ bdJarmyogjrS/Z5Zf/POJA70JzynodJtghcV//PF0717x+NCaDCDZr3uTfFTU4LTPzng awzPnPhK9BnuJmqjr8E17Be1gG1jMw9bfs9dbKHgi7F7gE41N6w0Ol4ptS9Ql9qSWhc1 kPgjhKb2xLO6n7q7POrOdRyJQwhKmFHPwz5/6vc3zoCwv1gnsBcB0a8akXRGF8Kqxncs buX/Dx/4Pqv05LE5ZRshDTEMS5qxOFxh8Tzexvu37dDiYHaZSyKWgMuGP6C1kUfeKRL/ pROw== X-Gm-Message-State: ANhLgQ2EyZtIM0pj+LbLoagBTNLyf/gNRB6nl6v+TI10Fl063Fx8ChU3 Uobob6cxKTBEtF90e6AEtiE= X-Google-Smtp-Source: ADFU+vunJX0vhEiGWr+cF6nyUd9Wl4qRvukRmkuzYyhzFQ9QRI9vRfCkaeMZ4NbBxWu8X8beLeF0Ag== X-Received: by 2002:ac8:4442:: with SMTP id m2mr19169229qtn.86.1583854076499; Tue, 10 Mar 2020 08:27:56 -0700 (PDT) Received: from ?IPv6:2601:282:803:7700:b876:5d04:c7e4:4480? ([2601:282:803:7700:b876:5d04:c7e4:4480]) by smtp.googlemail.com with ESMTPSA id g8sm15181301qke.1.2020.03.10.08.27.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 10 Mar 2020 08:27:55 -0700 (PDT) Subject: Re: IPv6 regression introduced by commit 3b6761d18bc11f2af2a6fc494e9026d39593f22c To: Alarig Le Lay Cc: netdev@vger.kernel.org, jack@basilfillan.uk, Vincent Bernat References: <20200305081747.tullbdlj66yf3w2w@mew.swordarmor.fr> <20200308105729.72pbglywnahbl7hs@mew.swordarmor.fr> <27457094-b62a-f029-e259-f7a274fee49d@gmail.com> <20200310103541.aplhwhfsvcflczhp@mew.swordarmor.fr> From: David Ahern Message-ID: <92f8ca32-af23-effd-55d8-8d1065f644f8@gmail.com> Date: Tue, 10 Mar 2020 09:27:53 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20200310103541.aplhwhfsvcflczhp@mew.swordarmor.fr> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 3/10/20 4:35 AM, Alarig Le Lay wrote: > On dim. 8 mars 20:15:14 2020, David Ahern wrote: >> If you are using x86 based CPU you can do this: >> perf probe ip6_dst_alloc%return ret=%ax >> >> perf record -e probe:* -a -g -- sleep 10 >> --> run this during the flapping >> >> perf script > > For this probe I see that: https://paste.swordarmor.fr/raw/pt9b none of the dst allocations are failing. Are the failing windows always ~30 seconds long? > >> this will show if the flapping is due to dst alloc failures. >> >> Other things to try: >> perf probe ip6_dst_gc >> perf stat -e probe:* -a -I 1000 >> --> will show calls/sec to running dst gc > > https://paste.swordarmor.fr/raw/uBnm This is not lining up with dst allocations above. gc function is only invoked from dst_alloc, and for ipv6 all dst allocations go through ip6_dst_alloc. > >> perf probe __ip6_rt_update_pmtu >> perf stat -e probe:* -a -I 1000 >> --> will show calls/sec to mtu updating > > This probe always stays at 0 even when the NDP is failing. > >> perf probe rt6_insert_exception >> perf state -e probe:* -a -I 1000 >> --> shows calls/sec to inserting exceptions > > Same as the last one. so no exception handling. How many ipv6 sockets are open? (ss -6tpn) How many ipv6 neighbor entries exist? (ip -6 neigh sh)