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 A1A7ACA9EAF for ; Tue, 22 Oct 2019 02:40:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 729B5214B2 for ; Tue, 22 Oct 2019 02:40:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="IEzAouKU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387538AbfJVCku (ORCPT ); Mon, 21 Oct 2019 22:40:50 -0400 Received: from mail-pl1-f169.google.com ([209.85.214.169]:46223 "EHLO mail-pl1-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727264AbfJVCku (ORCPT ); Mon, 21 Oct 2019 22:40:50 -0400 Received: by mail-pl1-f169.google.com with SMTP id q24so7571640plr.13 for ; Mon, 21 Oct 2019 19:40:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=iMhPIZNyIdvIDV2I55lP3X83QZvIWU0XIDvHalmkorg=; b=IEzAouKUhzPhbS8a95MfrQgFBuQU8k9vZUFMw2VsfGtIdeZeeaBdPTkUhBq1BWrhn3 hWoK1VUNnmW68adNsepy8Xp2/HgSxdSb1rIV/k4L9hgLKAPTV4JyiAWkQUQcNUkT2xy+ bmWsBhEaEhi/cYwLa46ekbcW6NcD3TobVpZ33cJwkqJmQ2W0JuL+6is2xWyWDmr+3ywA JWejdVbAynyfOIaUT2/LOQigtrD/rwkCpoC9Gm2ID3tNVPOyir4Z+i8hv6TUqJap3ZmD 47NrlsB29Eqn6EV41tJ3AlVIkxX/qv7gGwirRLvuKjoLiBWMnosuMZYQ5dnpHdWVFUsG QccQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=iMhPIZNyIdvIDV2I55lP3X83QZvIWU0XIDvHalmkorg=; b=iR54lMyq9kJmt8+6rVWcVEVtc2Vp3zhpxXkOuWtRXeS9xvWmS75zyJIi4rEPg9p41L EHdl8bWwuv6HvlVDsJci0ySB1iCD2m3Mf1f9TZL7gdQlYrsgkGRlu1lLSBHvIL5nd4fn zUcwhtP+C2RJljwoxrLeWqT5JAgLEhux6rHK/rAuNYOEH5Pm3tSISeveV4p+LZvBSYKm gkrRFe9XXIZBhHxXiTkdvn2fsQZ8KkhYWWljEpJXyzZ+BUJzpzPnlLLVt9gLDzvvo4Ei Z+AupS/MNA5Vmhz0BDE/Z2LeyT7d18o+CpXY27IXGYjS/1GYcJ9kR27y00ut785mtdPe 5B9Q== X-Gm-Message-State: APjAAAUaAubRCwiopyQTgHwiXImp10pbh/SL/tPP54YQqAu1pQV0/KkX WbvgOBA273S/sNVz6gz8+PVd0HwU X-Google-Smtp-Source: APXvYqz4pIA1a1/YAqHvxYoEFUubEcXndPKENN8Bnpd/WLVYYANVkZqhVyJro36CguHuMRaNYgXSXQ== X-Received: by 2002:a17:902:788d:: with SMTP id q13mr1228404pll.41.1571712049250; Mon, 21 Oct 2019 19:40:49 -0700 (PDT) Received: from [192.168.86.235] (c-73-241-150-70.hsd1.ca.comcast.net. [73.241.150.70]) by smtp.gmail.com with ESMTPSA id l24sm17507611pff.151.2019.10.21.19.40.48 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 21 Oct 2019 19:40:48 -0700 (PDT) Subject: Re: [net-next] tipc: improve throughput between nodes in netns To: Hoang Le , jon.maloy@ericsson.com, maloy@donjonn.com, tipc-discussion@lists.sourceforge.net, netdev@vger.kernel.org References: <20191022022036.19961-1-hoang.h.le@dektech.com.au> From: Eric Dumazet Message-ID: <88e00511-ae7f-cbd3-46b1-df0f0509c04e@gmail.com> Date: Mon, 21 Oct 2019 19:40:47 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20191022022036.19961-1-hoang.h.le@dektech.com.au> 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 10/21/19 7:20 PM, Hoang Le wrote: > n->net = net; > n->capabilities = capabilities; > + n->pnet = NULL; > + for_each_net_rcu(tmp) { This does not scale well, if say you have a thousand netns ? > + tn_peer = net_generic(tmp, tipc_net_id); > + if (!tn_peer) > + continue; > + /* Integrity checking whether node exists in namespace or not */ > + if (tn_peer->net_id != tn->net_id) > + continue; > + if (memcmp(peer_id, tn_peer->node_id, NODE_ID_LEN)) > + continue; > + > + hash_chk = tn_peer->random; > + hash_chk ^= net_hash_mix(&init_net); Why the xor with net_hash_mix(&init_net) is needed ? > + hash_chk ^= net_hash_mix(tmp); > + if (hash_chk ^ hash_mixes) > + continue; > + n->pnet = tmp; > + break; > + } How can we set n->pnet without increasing netns ->count ? Using check_net() later might trigger an use-after-free.