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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50654C433F5 for ; Fri, 12 Nov 2021 06:43:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2FB02604AC for ; Fri, 12 Nov 2021 06:43:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232841AbhKLGqa (ORCPT ); Fri, 12 Nov 2021 01:46:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48436 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230259AbhKLGq3 (ORCPT ); Fri, 12 Nov 2021 01:46:29 -0500 Received: from mail-ed1-x544.google.com (mail-ed1-x544.google.com [IPv6:2a00:1450:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 02346C061766; Thu, 11 Nov 2021 22:43:39 -0800 (PST) Received: by mail-ed1-x544.google.com with SMTP id f8so33926519edy.4; Thu, 11 Nov 2021 22:43:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=mXSkFnc6W0uhF72QqlDzmJCFzXvpezEdkesJtVNnp3E=; b=UpRk14MJ7uYWNUuWq6RGfSl03WE0hF/rRg8e3ANeTB90dB9PQHvdgrgRwe6VL5aSnH 6LfrlZ/Zpc6PlQFibFSYVOURI+qcjWMI7rSVy/N0GMRAN22lvWnZvotdM13snSHe0AQ0 2OUWUTLJsnneMa7zKIneZxyqwbITw9onKJ/+yxLr8CZoOJeO8yG6u83bz0V5FaM+FLqU AIXRkp/iXKAG0UCgSL0eqCMMEns5d1mCCRmXyPUxYHaiRTdfIkhm9FUc6ESHwxdvhSbo bskx4+UDUpHjYA+R/km39C3L0gBtQ1xtJFlwFHeeMvfHTfotl3Sd9kZ198pyjgxjyKJJ A2sQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=mXSkFnc6W0uhF72QqlDzmJCFzXvpezEdkesJtVNnp3E=; b=w/kuWxP/2ZjLtnkyWV9SezmOTDMwYliuP7RLAQlpSjFhy+usWioPVFB5kOBsCVN2T4 wbjChwNpCeu0L9dxDq3D3IMhV0hyWVX/TvM2hUJs8+eBtak7Ws9hVklqLhRNllv7Ymz2 D5TXPt7YkaX8Y1vqszJEjvJ+QPFoJakj0I7aALSq7DH2xSU/3akRxiBTD0uOulBd1y0V MBFKkZ54gs4NBv7fsI+FqS9Ukd2k+jx//RF/KTWT5iNSYAMZq4Cwf8fn3yAMY4iiGeoT qja0M/5wJvWNLMAfXFkBbYl285OD5sXBc5MyeX0f7lidNlfUwUmzZ97m3Oo/0YcaNtbO wGLQ== X-Gm-Message-State: AOAM5311BkL4zFaMoesNh7vOHfEJVXXfK1ZM0sCbTMfrobzsLXgTwYbW iIga29zhnnt8RUwXmlp9RYd+GQQGULSXw5hTNdI= X-Google-Smtp-Source: ABdhPJwbJWR2WlmTMbOdEF6bvWmcevTpX6YpBmODKhY0/OXyhaT7s03WYdjeMHmqzQQjTteukvUzoyLBuZqOB9LuTm4= X-Received: by 2002:a17:906:8a62:: with SMTP id hy2mr16490299ejc.347.1636699417619; Thu, 11 Nov 2021 22:43:37 -0800 (PST) MIME-Version: 1.0 References: <20211111133530.2156478-1-imagedong@tencent.com> <20211111060827.5906a2f9@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <20211111175032.14999302@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <20211111175032.14999302@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> From: Menglong Dong Date: Fri, 12 Nov 2021 14:42:23 +0800 Message-ID: Subject: Re: [PATCH net-next 0/2] net: snmp: tracepoint support for snmp To: Jakub Kicinski Cc: David Miller , Steven Rostedt , mingo@redhat.com, Hideaki YOSHIFUJI , dsahern@kernel.org, Menglong Dong , LKML , netdev Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Fri, Nov 12, 2021 at 9:50 AM Jakub Kicinski wrote: > > On Fri, 12 Nov 2021 09:40:47 +0800 Menglong Dong wrote: > > > I feel like I have seen this idea before. Is this your first posting? > > > > > > Would you mind including links to previous discussion if you're aware > > > of any? > > > > This is the first time that I post this patch. Do you mean that someone > > else has done this before? Sorry, I didn't find it~ > > I see. Yes, I believe very similar changes were proposed in the past. > > I believe that concerns about the performance impact had prevented them > from being merged. I have found a similar post: https://lore.kernel.org/netdev/20090303165747.GA1480@hmsreliant.think-freely.org/ And this is the tracepoint for kfree_skb(). I also concerns about the performance. However, with the tracepoints disabled, they don't have any impact; with enabled, their impact is no more than the tracepoint in kfree_skb() and consume_skb(). What's more, I have also realized another version: create tracepoint for every statistics type, such as snmp_udp_incsumerrors, snmp_udp_rcvbuferrors, etc. This can solve performance issue, as users can enable part of them, which may be triggered not frequently. However, too many tracepoint are created, and I think it may be not applicable. Thanks! Menglong Dong