From owner-freebsd-current@FreeBSD.ORG Thu Jul 29 03:57:07 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from green.homeunix.org (freefall.freebsd.org [216.136.204.21]) by hub.freebsd.org (Postfix) with ESMTP id DC34D16A4CE; Thu, 29 Jul 2004 03:57:06 +0000 (GMT) Received: from green.homeunix.org (green@localhost [127.0.0.1]) by green.homeunix.org (8.12.11/8.12.11) with ESMTP id i6T3v6TV001080; Wed, 28 Jul 2004 23:57:06 -0400 (EDT) (envelope-from green@green.homeunix.org) Received: (from green@localhost) by green.homeunix.org (8.12.11/8.12.11/Submit) id i6T3v5gd001079; Wed, 28 Jul 2004 23:57:05 -0400 (EDT) (envelope-from green) Date: Wed, 28 Jul 2004 23:57:04 -0400 From: Brian Fundakowski Feldman To: Maxim Maximov Message-ID: <20040729035704.GA1021@green.homeunix.org> References: <200407281329.27271.jhb@FreeBSD.org> <41086F25.3070707@mcsi.pp.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <41086F25.3070707@mcsi.pp.ru> User-Agent: Mutt/1.5.6i cc: current@freebsd.org Subject: Re: A couple of SMP deadlock patches 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: Thu, 29 Jul 2004 03:57:07 -0000 On Thu, Jul 29, 2004 at 07:29:41AM +0400, Maxim Maximov wrote: > John Baldwin wrote: > >Included below are two patches for two different potential deadlocks on > >SMP. The first one I have sent to the list before, but it didn't seem to > >help anyone. I do believe it is a fix for a possible deadlock though so > >I'd like some more testing feedback with the aim of committing it. The > >second patch works around a lock order reversal introduced with the sleep > >queue code (since sched_lock's scope was reduced) at the expense of > >increasing the latency between a swapped out thread becoming runnable and > >the swapper waking up to swap the process back in. > > I'm sorry, but for me PREEMPTION defined in kernel with these patches is > still causing deadlocks. SMP, HTT enabled. These changes seem totally unrelated to my instability with PREEMPTION (so I didn't try to enable it at all, but am running with these changes). They should instead fix some issues Kris Kennaway has been seeing with the ports cluster (but I have not tried to reproduce myself). -- Brian Fundakowski Feldman \'[ FreeBSD ]''''''''''\ <> green@FreeBSD.org \ The Power to Serve! \ Opinions expressed are my own. \,,,,,,,,,,,,,,,,,,,,,,\