From owner-svn-src-all@FreeBSD.ORG Thu Mar 17 05:00:33 2011 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5C90A1065688; Thu, 17 Mar 2011 05:00:33 +0000 (UTC) (envelope-from julian@freebsd.org) Received: from vps1.elischer.org (vps1.elischer.org [204.109.63.16]) by mx1.freebsd.org (Postfix) with ESMTP id 26E868FC2F; Thu, 17 Mar 2011 05:00:32 +0000 (UTC) Received: from julian-mac.elischer.org (home-nat.elischer.org [67.100.89.137]) (authenticated bits=0) by vps1.elischer.org (8.14.4/8.14.4) with ESMTP id p2H4eMWW095598 (version=TLSv1/SSLv3 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO); Wed, 16 Mar 2011 21:40:23 -0700 (PDT) (envelope-from julian@freebsd.org) Message-ID: <4D8190C1.4090004@freebsd.org> Date: Wed, 16 Mar 2011 21:40:33 -0700 From: Julian Elischer User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X 10.4; en-US; rv:1.9.2.15) Gecko/20110303 Thunderbird/3.1.9 MIME-Version: 1.0 To: Ivan Voras References: <201103152145.p2FLjAlt060256@svn.freebsd.org> <20110316004503.GM99496@mdounin.ru> <201103161233.16347.jkim@FreeBSD.org> <20110316174553.GA6367@freebsd.org> <20110316200346.GA36431@owl.midgard.homeip.net> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Erik Trulsson , src-committers@freebsd.org, Roman Divacky , svn-src-head@freebsd.org, svn-src-all@freebsd.org, Jung-uk Kim Subject: Re: svn commit: r219679 - head/sys/i386/include X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Mar 2011 05:00:33 -0000 On 3/16/11 2:16 PM, Ivan Voras wrote: > On 16 March 2011 21:03, Erik Trulsson wrote: >> On Wed, Mar 16, 2011 at 06:45:53PM +0100, Roman Divacky wrote: >>> On Wed, Mar 16, 2011 at 12:32:56PM -0400, Jung-uk Kim wrote: >>>> On Tuesday 15 March 2011 08:45 pm, Maxim Dounin wrote: >>>>> This isn't really different as long as GENERIC kernel used, as >>>>> GENERIC defines I486_CPU. >>>> Fixed in r219698, sorry. >>>> >>>> Actually, I think we should remove i486 from GENERIC at some point. >>>> It has too many limitations. For example, I really love to implement >>>> atomic 64-bit mem read/write using cmpxchg8b (no 0xf00f joke, please) >>>> but I cannot do that cleanly without removing I486 support or >>>> checking cpu_class at run-time. :-( >>> if we drop i486 I think it makes sense to require something that has >>> at least SSE2, thus we can have the same expectations as on amd64. >> No, that would remove support from far too many machines that people >> actually use to run FreeBSD. >> There are probably only a handful of people (if that) who actually run >> FreeBSD on an actual 486-class machine, but requiring SSE2 would mean >> dropping support for Pentium-III and Athlon-XP equipped machines and >> I believe there are a large number of such machines still in use, and >> they are still perfectly suitable for a large number of tasks. > This is understandable but I also think it deserves a poll at stable@ > and current@. It might be worth keeping i486 for all of 9-stable but > removing it before 10-stable. Judging from previous releases, 9.x > would be supported until at least 2016. I don't follow the embedded > world that much, but from what I saw, most (incl. Soekris) are moving > to Atom designs which support SSE2. not sure what is in the Soekris and other embedded machines but do keep them in mind. many are now 586 class I guess but there may still be some 486 ones around. I believe you can now get a 486 core in some arrays. >