From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f171.google.com (mail-wi0-f171.google.com [209.85.212.171]) by kanga.kvack.org (Postfix) with ESMTP id D5C516B0036 for ; Wed, 9 Apr 2014 11:39:25 -0400 (EDT) Received: by mail-wi0-f171.google.com with SMTP id q5so9149079wiv.4 for ; Wed, 09 Apr 2014 08:39:24 -0700 (PDT) Received: from mx2.suse.de (cantor2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id cy3si2996434wib.39.2014.04.09.08.39.22 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 09 Apr 2014 08:39:23 -0700 (PDT) Date: Wed, 9 Apr 2014 16:39:17 +0100 From: Mel Gorman Subject: Re: [PATCH 2/3] x86: Define _PAGE_NUMA with unused physical address bits PMD and PTE levels Message-ID: <20140409153916.GT7292@suse.de> References: <20140407182854.GH7292@suse.de> <5342FC0E.9080701@zytor.com> <20140407193646.GC23983@moon> <5342FFB0.6010501@zytor.com> <20140407212535.GJ7292@suse.de> <20140408160250.GE31554@phenom.dumpdata.com> <20140408165123.GN7292@suse.de> <20140409151827.GA6445@phenom.dumpdata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20140409151827.GA6445@phenom.dumpdata.com> Sender: owner-linux-mm@kvack.org List-ID: To: Konrad Rzeszutek Wilk Cc: "H. Peter Anvin" , Steven Noonan , Cyrill Gorcunov , David Vrabel , Linus Torvalds , Ingo Molnar , Rik van Riel , Andrew Morton , Peter Zijlstra , Andrea Arcangeli , Linux-MM , Linux-X86 , LKML , Pavel Emelyanov On Wed, Apr 09, 2014 at 11:18:27AM -0400, Konrad Rzeszutek Wilk wrote: > On Tue, Apr 08, 2014 at 05:51:23PM +0100, Mel Gorman wrote: > > On Tue, Apr 08, 2014 at 12:02:50PM -0400, Konrad Rzeszutek Wilk wrote: > > > .snip.. > > > > >>> David Vrabel has a patchset which I presumed would be pulled through > > > > >the > > > > >>> Xen tree this merge window: > > > > >>> > > > > >>> [PATCHv5 0/8] x86/xen: fixes for mapping high MMIO regions (and > > > > >remove > > > > >>> _PAGE_IOMAP) > > > > >>> > > > > >>> That frees up this bit. > > > > >>> > > > > >> > > > > >> Thanks, I was not aware of that patch. Based on it, I intend to > > > > >force > > > > >> automatic NUMA balancing to depend on !XEN and see what the reaction > > > > >is. If > > > > >> support for Xen is really required then it potentially be re-enabled > > > > >if/when > > > > >> that series is merged assuming they do not need the bit for something > > > > >else. > > > > >> > > > > > > > > > >Amazon EC2 does have large memory instance types with NUMA exposed to > > > > >the guest (e.g. c3.8xlarge, i2.8xlarge, etc), so it'd be preferable > > > > >(to me anyway) if we didn't require !XEN. > > > > > > What about the patch that David Vrabel posted: > > > > > > http://osdir.com/ml/general/2014-03/msg41979.html > > > > > > Has anybody taken it for a spin? > > > > Alternatively "[PATCH 4/5] mm: use paravirt friendly ops for NUMA > > hinting ptes" which modifies the NUMA pte helpers instead of the main > > set/clear ones. > > Ah nice! Looking forward to it being posted as non-RFC and could you also > please CC 'xen-devel@lists.xenproject.org' on it? > Yes I will. Unless the x86 maintainers push for it on the grounds that it is a functional fix for xen, I'm going to wait until after the merge window to resend it. That'd give it some chance of being tested in -next before hitting mainline. -- Mel Gorman SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org