From owner-freebsd-current Tue May 28 11:56:56 2002 Delivered-To: freebsd-current@freebsd.org Received: from mail.speakeasy.net (mail12.speakeasy.net [216.254.0.212]) by hub.freebsd.org (Postfix) with ESMTP id 3544B37B40F for ; Tue, 28 May 2002 11:56:29 -0700 (PDT) Received: (qmail 19773 invoked from network); 28 May 2002 18:56:25 -0000 Received: from unknown (HELO server.baldwin.cx) ([216.27.160.63]) (envelope-sender ) by mail12.speakeasy.net (qmail-ldap-1.03) with DES-CBC3-SHA encrypted SMTP for ; 28 May 2002 18:56:25 -0000 Received: from laptop.baldwin.cx (gw1.twc.weather.com [216.133.140.1]) by server.baldwin.cx (8.11.6/8.11.6) with ESMTP id g4SIuaF24347; Tue, 28 May 2002 14:56:36 -0400 (EDT) (envelope-from jhb@FreeBSD.org) Message-ID: X-Mailer: XFMail 1.5.2 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <200205280810.g4S8Ah3i071756@rina.r.dl.itc.u-tokyo.ac.jp> Date: Tue, 28 May 2002 14:56:04 -0400 (EDT) From: John Baldwin To: Seigo Tanimura Subject: Re: preemption across processors Cc: current@FreeBSD.org Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG > The prototype patch is at: > > http://people.FreeBSD.org/~tanimura/patches/ippreempt.diff.gz > > And the p4 depot > > //depot/user/tanimura/ippreempt/... > > The patch is for only i386 at the moment. > > The following is the brief description of the patch: I would prefer that this was hung off the preemption stuff I've already done rather than reinventing it. I would also prefer that we get a preemptive kernel w/o this done stable before adding extra complication. > Miscellaneous stuff: > > If a thread spins for an adaptive mutex, propagate its priority to the > owner thread of the mutex. This prevents preemption of the owner > thread by a thread with the priority in between the owner thread and > the spinning thread. Ewww, I'd rather avoid this if possible. This is just an optimization, but it would depend on how complicated this makes the mutex code to see if it's worth it or not. -- 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-current" in the body of the message