From owner-freebsd-current@FreeBSD.ORG Wed Apr 27 18:45:52 2005 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3452F16A4CE for ; Wed, 27 Apr 2005 18:45:52 +0000 (GMT) Received: from mail25.sea5.speakeasy.net (mail25.sea5.speakeasy.net [69.17.117.27]) by mx1.FreeBSD.org (Postfix) with ESMTP id C990B43D5F for ; Wed, 27 Apr 2005 18:45:51 +0000 (GMT) (envelope-from jhb@FreeBSD.org) Received: (qmail 31847 invoked from network); 27 Apr 2005 18:45:51 -0000 Received: from server.baldwin.cx ([216.27.160.63]) (envelope-sender )AES256-SHA encrypted SMTP for ; 27 Apr 2005 18:45:50 -0000 Received: from [10.50.41.242] (gw1.twc.weather.com [216.133.140.1]) (authenticated bits=0) by server.baldwin.cx (8.13.1/8.13.1) with ESMTP id j3RIiqag044824; Wed, 27 Apr 2005 14:45:38 -0400 (EDT) (envelope-from jhb@FreeBSD.org) From: John Baldwin To: freebsd-current@FreeBSD.org Date: Wed, 27 Apr 2005 14:10:00 -0400 User-Agent: KMail/1.8 References: <1114052573.1075.10.camel@dirk.no.domain> <20050422200102.G10333@carver.gumbysoft.com> <4269C309.30702@freebsd.org> In-Reply-To: <4269C309.30702@freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200504271410.02151.jhb@FreeBSD.org> X-Spam-Status: No, score=-102.8 required=4.2 tests=ALL_TRUSTED, USER_IN_WHITELIST autolearn=failed version=3.0.2 X-Spam-Checker-Version: SpamAssassin 3.0.2 (2004-11-16) on server.baldwin.cx cc: David Xu cc: Sam Lawrance Subject: Re: kern/78474 for 5.4? (kernel stack swapout problem again) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Apr 2005 18:45:52 -0000 On Friday 22 April 2005 11:37 pm, David Xu wrote: > Doug White wrote: > >On Thu, 21 Apr 2005, David Xu wrote: > >>Sam Lawrance wrote: > >>>Will this problem: > >>> > >>>Swapped out procs not brought in immediately after child exits > >>>http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/78474 > >>> > >>>be dealt with for the release of 5.4? > >>> > >>>Perhaps I'm the only FreeBSD user with swapped out processes ;-) > >>> > >>>-Sam > >> > >>I have noticed that current spinlock implementation no longer means that > >>CPU must be in critical region (critical_enter is called), even previous > >>hack TDP_WAKEPROC0 is no longer correct, :(, I think it is the time to > >>disable swapout. > > > >I'm sorry, I can't parse your double negative. On -CURRENT critical > >sections (entered with critical_enter()) no longer disable interrupts, but > >do inhibit preemption. But spinlocks still do critical_enter() (see > >spinlock_enter()). > > I will commit the patch provided in the PR, it should work. I am just > worrying > TDP_WAKEPROC0 will not work if spinlock does not entering critical region. Read what Doug wrote. spinlock_enter() still calls critical_enter(), so all spin locks still contain critical sections. -- John Baldwin <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.org