Return-Path: linux-nfs-owner@vger.kernel.org Received: from hydra.sisk.pl ([212.160.235.94]:55540 "EHLO hydra.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753616Ab3CEXzw (ORCPT ); Tue, 5 Mar 2013 18:55:52 -0500 From: "Rafael J. Wysocki" To: "J. Bruce Fields" Cc: Tejun Heo , Jeff Layton , "Myklebust, Trond" , Oleg Nesterov , Mandeep Singh Baines , Ming Lei , Linux Kernel Mailing List , "linux-nfs@vger.kernel.org" , Andrew Morton , Ingo Molnar Subject: Re: LOCKDEP: 3.9-rc1: mount.nfs/4272 still has locks held! Date: Wed, 06 Mar 2013 01:02:46 +0100 Message-ID: <5144293.t44nDELk4d@vostro.rjw.lan> In-Reply-To: <20130305231110.GK15816@fieldses.org> References: <20130305174954.GG12795@htj.dyndns.org> <20130305231110.GK15816@fieldses.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Tuesday, March 05, 2013 06:11:10 PM J. Bruce Fields wrote: > On Tue, Mar 05, 2013 at 09:49:54AM -0800, Tejun Heo wrote: > > On Tue, Mar 05, 2013 at 09:46:48AM -0800, Tejun Heo wrote: > > > So, I think this is why implementing freezer as a separate blocking > > > mechanism isn't such a good idea. We're effectively introducing a > > > completely new waiting state to a lot of unsuspecting paths which > > > generates a lot of risks and eventually extra complexity to work > > > around those. I think we really should update freezer to re-use the > > > blocking points we already have - the ones used for signal delivery > > > and ptracing. That way, other code paths don't have to worry about an > > > extra stop state and we can confine most complexities to freezer > > > proper. > > > > Also, consolidating those wait states means that we can solve the > > event-to-response latency problem for all three cases - signal, ptrace > > and freezer, rather than adding separate backing-out strategy for > > freezer. > > Meanwhile, as none of this sounds likely to be done this time > around--are we backing out the new lockdep warnings? I think we should do that. Thanks, Rafael -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.