Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755223AbZIVNUP (ORCPT ); Tue, 22 Sep 2009 09:20:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754642AbZIVNUO (ORCPT ); Tue, 22 Sep 2009 09:20:14 -0400 Received: from gir.skynet.ie ([193.1.99.77]:36768 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754474AbZIVNUN (ORCPT ); Tue, 22 Sep 2009 09:20:13 -0400 Date: Tue, 22 Sep 2009 14:20:19 +0100 From: Mel Gorman To: Sachin Sant Cc: Christoph Lameter , Nick Piggin , Pekka Enberg , heiko.carstens@de.ibm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Tejun Heo , Benjamin Herrenschmidt Subject: Re: [RFC PATCH 0/3] Fix SLQB on memoryless configurations V2 Message-ID: <20090922132018.GB25965@csn.ul.ie> References: <1253549426-917-1-git-send-email-mel@csn.ul.ie> <20090921174656.GS12726@csn.ul.ie> <20090921180739.GT12726@csn.ul.ie> <4AB85A8F.6010106@in.ibm.com> <20090922125546.GA25965@csn.ul.ie> <4AB8CB81.4080309@in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <4AB8CB81.4080309@in.ibm.com> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2795 Lines: 73 On Tue, Sep 22, 2009 at 06:35:05PM +0530, Sachin Sant wrote: > Mel Gorman wrote: >> On Tue, Sep 22, 2009 at 10:33:11AM +0530, Sachin Sant wrote: >> >>> Mel Gorman wrote: >>> >>>> On Mon, Sep 21, 2009 at 01:54:12PM -0400, Christoph Lameter wrote: >>>> >>>>> Lets just keep SLQB back until the basic issues with memoryless nodes are >>>>> resolved. >>>>> >>>> It's not even super-clear that the memoryless nodes issues are entirely >>>> related to SLQB. Sachin for example says that there was a stall issue >>>> with memoryless nodes that could be triggered without SLQB. Sachin, is >>>> that still accurate? >>>> >>> I think there are two different problems that we are dealing with. >>> >>> First one is the SLQB not working on a ppc64 box which seems to be specific >>> to only one machine and i haven't seen that on other power boxes.The patches >>> that you have posted seems to allow the box to boot, but eventually it hits >>> the stall issue(related to percpu dynamic allocator not working on ppc64), >>> which is the second problem we are dealing with. >>> >>> >> >> Ok, I've sent out V3 of this. It's only a partial fix but it's about as >> far as it can be brought until the other difficulties are resolved. >> > Thanks Mel. > >> >>> The stall issue seems to be much more critical as it is affecting almost >>> all of the power boxes that i have tested with (4 in all). >>> This issue is seen with Linus tree as well and was first seen with >>> 2.6.31-git5 (0cb583fd..) >>> >>> The stall issue was reported here: >>> http://lists.ozlabs.org/pipermail/linuxppc-dev/2009-September/075791.html >>> >>> >> >> Can you bisect this please? >> > The problem seems to have been introduced with > commit ada3fa15057205b7d3f727bba5cd26b5912e350f. > > Specifically this patch : powerpc64: convert to dynamic percpu allocator > That is commit c2a7e818019f20a5cf7fb26a6eb59e212e6c0cd8. > If i revert this patch i am able to boot latest git > on a powerpc box. > Ok, this is then independent of the corruption I was seeing which I now believe is based entirely within SLQBs handling of remote nodes. I was based on 2.6.31 with SLQB applied on top. This patch was applied in a time after the baseline I was working from. Tejun, have you looked at that stall problem? Sorry if you have already, I haven't dug around for related threads. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/