From owner-freebsd-stable@FreeBSD.ORG Sat Jan 27 03:01:43 2007 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 1181B16A400 for ; Sat, 27 Jan 2007 03:01:43 +0000 (UTC) (envelope-from john_m_cooper@yahoo.com) Received: from smtp106.biz.mail.re2.yahoo.com (smtp106.biz.mail.re2.yahoo.com [206.190.52.175]) by mx1.freebsd.org (Postfix) with SMTP id B177913C483 for ; Sat, 27 Jan 2007 03:01:42 +0000 (UTC) (envelope-from john_m_cooper@yahoo.com) Received: (qmail 82592 invoked from network); 27 Jan 2007 02:35:01 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Received:X-YMail-OSG:Received:Message-ID:Date:From:User-Agent:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=Cu1idbx2s4OlVxeGCE9TAOMRqA6BupgVuzMBfPTepHEf1ivDnImkYK+2eXWcQ9lNAZxKCVuWUW5vCZphsp49HQA/aH/tADzyWLFf0TKnq8sByMDVfq3o136KFyT1UDZreIo3ciCZKAehR0ZKZH/0kAzOt485RTczYHvip9fXJDU= ; Received: from unknown (HELO borgdemon2.10500cascaderuncourt.home) (j.m.cooper@borgsdemons.com@68.33.224.115 with login) by smtp106.biz.mail.re2.yahoo.com with SMTP; 27 Jan 2007 02:35:00 -0000 X-YMail-OSG: AVhFBkEVM1mc86t9hXOkplc9RSFc33c6K_FWHhc1LZJrywBYOD14usgQuprB8LgvGhD2yMiJjdoTlxWqGNnOCB47RA_MBGPUZmZGy5i9IgpFxAIZpfab7vA6yCzEBpNE6nQxG0vOOKyBkBy_iQucEMLPng7ZaLWi4HNS0d5ZAY7gJe4U0F_bRScOi4VT Received: from [127.0.0.1] (localhost [127.0.0.1]) by borgdemon2.10500cascaderuncourt.home (Postfix) with ESMTP id 66A555C3A; Fri, 26 Jan 2007 21:35:00 -0500 (EST) Message-ID: <45BABA54.2020405@yahoo.com> Date: Fri, 26 Jan 2007 21:35:00 -0500 From: John Merryweather Cooper User-Agent: Thunderbird 1.5.0.9 (X11/20070121) MIME-Version: 1.0 To: "Chris H." References: <20070126173313.y153cjd400so0kk8@webmail.1command.com> In-Reply-To: <20070126173313.y153cjd400so0kk8@webmail.1command.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "\[FBSDS\]" Subject: Re: Why does FBSD always assume it's on an 8080 CPU? X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 27 Jan 2007 03:01:43 -0000 Chris H. wrote: > ...or when will FreeBSD support Pentium features? > > I want to apologize in advance if this should be on the kern@ > But it seemed apropriate for this list too and I'm already on it. > I've noticed building kernels, that since v. >= 5 that during > the phase 2/3 all the lines echoed to the screen contain: > -mno-mmx -mno-3dnow -mno-sse -mno-sse2 ... > As Pentium have been the "norm" for many years now, why aren't > these /assumed/? I'm building on several SMP PIII's and a build > is in process now on a PIV Athalon running 6.2 the source and > ports tree were cvsupped 01-25 @02:03:00 -0800. Yet this > current kernel build is echoing these same -mno- lines. I have > machine i386 > cpu I686_CPU > device apic > uncommented and I386_CPU, I486_CPU & I586_CPU commented. I have > grepped the /src/sys/conf/NOTES as well as the /src/sys/i386/conf/NOTES > Yet the only case I find relating to this is on line: 130 in: > /src/sys/i386/conf/NOTES which reads: > # CPU_ENABLE_SSE enables SSE/MMX2 instructions support. This is default > # on I686_CPU and above. > Default? hmmm... not as far as I can tell. Anyway, I would *greatly* > appreciate any insight on this issue. Do I need to pollute my make.conf > file to achive a Pentium kernel? > > Thank you very much for all your time and consideration. > > --Chris > > Context switching. We already preserve the "core" CPU state and the FPU state between context switches. Adding MMX into the mix means preserving an MMX state (since it can clobber the FPU state) and so forth. jmc