Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753940AbYAZHNy (ORCPT ); Sat, 26 Jan 2008 02:13:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751338AbYAZHNs (ORCPT ); Sat, 26 Jan 2008 02:13:48 -0500 Received: from E23SMTP04.au.ibm.com ([202.81.18.173]:56190 "EHLO e23smtp04.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751316AbYAZHNq (ORCPT ); Sat, 26 Jan 2008 02:13:46 -0500 Date: Sat, 26 Jan 2008 12:43:39 +0530 From: Balbir Singh To: Michael Ellerman Cc: linuxppc-dev@ozlabs.org, LKML , Paul Mackerras Subject: Re: [PATCH] Fake NUMA emulation for PowerPC (Take 2) Message-ID: <20080126071339.GA25328@balbir.in.ibm.com> Reply-To: balbir@linux.vnet.ibm.com Mail-Followup-To: Michael Ellerman , linuxppc-dev@ozlabs.org, LKML , Paul Mackerras References: <20071207223714.11448.91386.sendpatchset@balbir-laptop> <1200634493.7806.0.camel@concordia.ozlabs.ibm.com> <1200635099.7806.3.camel@concordia.ozlabs.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <1200635099.7806.3.camel@concordia.ozlabs.ibm.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2318 Lines: 78 * Michael Ellerman [2008-01-18 16:44:58]: > > This fixes it, although I'm a little worried about some of the > removals/movings of node_set_online() in the patch. > > > diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c > index 1666e7d..dcedc26 100644 > --- a/arch/powerpc/mm/numa.c > +++ b/arch/powerpc/mm/numa.c > @@ -49,7 +49,6 @@ static int __cpuinit fake_numa_create_new_node(unsigned long end_pfn, > static unsigned int fake_nid = 0; > static unsigned long long curr_boundary = 0; > > - *nid = fake_nid; > if (!p) > return 0; > > @@ -60,6 +59,7 @@ static int __cpuinit fake_numa_create_new_node(unsigned long end_pfn, > if (mem < curr_boundary) > return 0; > > + *nid = fake_nid; > curr_boundary = mem; > > if ((end_pfn << PAGE_SHIFT) > mem) { > Hi, Michael, Here's a better and more complete fix for the problem. Could you please see if it works for you? I tested it on a real NUMA box and it seemed to work fine there. Description ----------- This patch provides a fix for the problem found by Michael Ellerman while using fake NUMA nodes on a cell box. The code modifies node id iff (as in if and only if) fake NUMA nodes are created. Signed-off-by: Balbir Singh --- arch/powerpc/mm/numa.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff -puN arch/powerpc/mm/numa.c~fix-fake-numa-nid-on-numa arch/powerpc/mm/numa.c --- linux-2.6.24-rc8/arch/powerpc/mm/numa.c~fix-fake-numa-nid-on-numa 2008-01-26 12:20:29.000000000 +0530 +++ linux-2.6.24-rc8-balbir/arch/powerpc/mm/numa.c 2008-01-26 12:27:53.000000000 +0530 @@ -49,7 +49,12 @@ static int __cpuinit fake_numa_create_ne static unsigned int fake_nid = 0; static unsigned long long curr_boundary = 0; - *nid = fake_nid; + /* + * If we did enable fake nodes and cross a node, + * remember the last node and start from there. + */ + if (fake_nid) + *nid = fake_nid; if (!p) return 0; _ -- Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL -- 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/