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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 76CE1C433FE for ; Sat, 12 Nov 2022 07:53:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234325AbiKLHxw (ORCPT ); Sat, 12 Nov 2022 02:53:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34860 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232943AbiKLHxu (ORCPT ); Sat, 12 Nov 2022 02:53:50 -0500 Received: from mail-wr1-x42d.google.com (mail-wr1-x42d.google.com [IPv6:2a00:1450:4864:20::42d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA70B55A4 for ; Fri, 11 Nov 2022 23:53:47 -0800 (PST) Received: by mail-wr1-x42d.google.com with SMTP id d9so4420563wrm.13 for ; Fri, 11 Nov 2022 23:53:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=resnulli-us.20210112.gappssmtp.com; s=20210112; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=VMzacoN6vjh7WbGaZ9Fu+CzW5whG2XJrlcSaFUOkTfs=; b=Vr/X3nBTBFZXGxJR2ZtOST8HBJJtfP3OPyKhLw0exZDW2rug0maAiNrRg17TDTZRlA 6bo5RGjP28zcACvmwMCnGZTIdZhg+B23E/qNegsUmZDIbG/d1Uifq3I8GBGmLz0/ED79 1uk3iqpkUWz2yZsq5eBDPVhHb2EMhnSUotK2Hvlc7QbJyjdeVNFlt1Ppl2vrbZUFoFXg dWNa/kMyE8VUDs8mg+9m2rL+r9r5xME1T9/8/0ZI5ayxYgzxT1cuH/Fej8+aWtDKM5d6 Sn6azD91+xz1uLePkikzYjlb3QQU/sz3+y9wy8gv/a0rgz5SdwwBKCrgBauylEq04/GQ g71Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=VMzacoN6vjh7WbGaZ9Fu+CzW5whG2XJrlcSaFUOkTfs=; b=5EDxjxFZThmR7TUan05aa8iGkwbzBv4hJ54ioGlP+5gK7UxWsmiRl9Gez+MkfzzPFi sjmcQUS79GcVsudIGGj01P4G5p5vwNZA4tN7ZYwql4U22Bg4mM3cEvnT1FHybxE7cRRk 2yu/vlDnJsg1A2U1y66NKZsHATL6vX+iefSI6rlTUfrWKUekuvrEhpmXK23a8exKu+5B GfNfDoHsb8eegMW5dNwB8Qm58fFF7OWoBP+jQnbQmH0lnuAicS6sjjzJvzKFXv/93vBp Uqmzz2O8k+iTHjCOF+oq3nIptSbddmc6nJ/XWrCfXvZ1Uv4Vvhe6ungaFCHoFQF3HaxW OKeQ== X-Gm-Message-State: ANoB5pnlfmqNsgAI2fOYixsZZ27UmlpBfXU6HL736WTARdvfA5Hj82ki faOEt0PXJP+6cdXqrUaFzApPMi6ZMDTVt1VD X-Google-Smtp-Source: AA0mqf7MrXsXbFVieHgTqIU9AI6pdfpA3c0rc2d08vYkrHMP99oFna8xtIv2rFs09XhjXaAGOPe+4A== X-Received: by 2002:a5d:414d:0:b0:236:5e78:b1af with SMTP id c13-20020a5d414d000000b002365e78b1afmr2866755wrq.266.1668239626102; Fri, 11 Nov 2022 23:53:46 -0800 (PST) Received: from localhost (host-213-179-129-39.customer.m-online.net. [213.179.129.39]) by smtp.gmail.com with ESMTPSA id c17-20020adffb11000000b002417f35767asm477783wrr.40.2022.11.11.23.53.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 11 Nov 2022 23:53:45 -0800 (PST) Date: Sat, 12 Nov 2022 08:53:43 +0100 From: Jiri Pirko To: Andrew Lunn Cc: John Ousterhout , Stephen Hemminger , netdev@vger.kernel.org Subject: Re: Upstream Homa? Message-ID: References: <20221110132540.44c9463c@hermes.local> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Fri, Nov 11, 2022 at 08:25:44PM CET, andrew@lunn.ch wrote: >On Fri, Nov 11, 2022 at 10:59:58AM -0800, John Ousterhout wrote: >> The netlink and 32-bit kernel issues are new for me; I've done some digging to >> learn more, but still have some questions. >> > >> * Is the intent that netlink replaces *all* uses of /proc and ioctl? Homa >> currently uses ioctls on sockets for I/O (its APIs aren't sockets-compatible). Why exactly it isn't sockets-comatible? >> It looks like switching to netlink would double the number of system calls that >> have to be invoked, which would be unfortunate given Homa's goal of getting the >> lowest possible latency. It also looks like netlink might be awkward for >> dumping large volumes of kernel data to user space (potential for buffer >> overflow?). Netlink is slow, you should use it for fast path. It is for configuration and stats.