From owner-freebsd-advocacy Thu Dec 20 14:51:33 2001 Delivered-To: freebsd-advocacy@freebsd.org Received: from mail5.speakeasy.net (mail5.speakeasy.net [216.254.0.205]) by hub.freebsd.org (Postfix) with ESMTP id 794DE37B416 for ; Thu, 20 Dec 2001 14:51:30 -0800 (PST) Received: (qmail 22568 invoked from network); 20 Dec 2001 22:51:27 -0000 Received: from unknown (HELO laptop.baldwin.cx) ([64.81.54.73]) (envelope-sender ) by mail5.speakeasy.net (qmail-ldap-1.03) with SMTP for ; 20 Dec 2001 22:51:27 -0000 Message-ID: X-Mailer: XFMail 1.4.0 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <026b01c189a6$3bb4b6c0$0a00000a@atkielski.com> Date: Thu, 20 Dec 2001 14:51:02 -0800 (PST) From: John Baldwin To: Anthony Atkielski Subject: Re: Microsoft Advocacy? Cc: Jeremiah Gowdy , Cc: Jeremiah Gowdy , Gilbert Gong , advocacy@FreeBSD.org Sender: owner-freebsd-advocacy@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On 20-Dec-01 Anthony Atkielski wrote: > John writes: > >> Some said (rough paraphrase): >> >> FreeBSD is suitable for use as a desktop for >> specific circumstances. >> >> This is equivalent to: >> >> FreeBSD is suitable for use as a desktop for >> at least one circumstance. >> >> Jeremiah replied with: >> >> "I do not agree." >> >> Which is equivalent to: >> >> FreeBSD is not suitable for use as a desktop >> for at least one circumstance. >> >> Which is equivalent to: >> >> FreeBSD is not suitable for use as a desktop >> for any circumstance. > > Your logic is flawed. Your last two conclusions do not follow from the > first three statements. Hrm, ok, note that statement 3 is simply statement 2 with a "not" added due to the negation. Can you show the logic error regarding equivalence of either 1 and 2 or 3 and 4 then? > Consider this: > > SomeoneBelieves = OSFree && Suitability && Desktop && Specific; > JeremiahBelieves = !(OSType && Suitability && Desktop && Specific); Err, this is not valid. There aren't 4 statements there are two: (1) For a specific instance, (2) FreeBSD is valid as a desktop. > Now I'm getting worried about spin mutexes and locks. Are you completely > sure about those? Yes, I'm fairly sure. Do you have any notion of how Unix works? All its data protection was by disabling interrupts (short-term protection which is what spin mutexes provide) since it was designed for a UP machine. On SMP blocking interrupts is not sufficient protection because another CPU could be executing the same or similar code, hence the need to synchronize via a spin lock. However, if we know we are not SMP (i.e. a UP kernel) we don't have to worry about synchronizing with another CPU, and can simply disable interrupts. -- John Baldwin <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-advocacy" in the body of the message