From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760131Ab0JGHmX (ORCPT ); Thu, 7 Oct 2010 03:42:23 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:52716 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751173Ab0JGHmW (ORCPT ); Thu, 7 Oct 2010 03:42:22 -0400 Date: Thu, 7 Oct 2010 00:42:52 -0700 From: Andrew Morton To: Nikanth Karthikesan Cc: linux-kernel@vger.kernel.org, x86@kernel.org, Yinghai Lu , Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner Subject: Re: [PATCH] Assign CPUs to nodes in round-robin manner on Fake NUMA. Message-Id: <20101007004252.599b6888.akpm@linux-foundation.org> In-Reply-To: <201009301734.10787.knikanth@suse.de> References: <201009301734.10787.knikanth@suse.de> X-Mailer: Sylpheed 2.7.1 (GTK+ 2.18.9; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 30 Sep 2010 17:34:10 +0530 Nikanth Karthikesan wrote: > Assign CPUs to nodes in round-robin manner on Fake NUMA. > > commit d9c2d5ac6af87b4491bff107113aaf16f6c2b2d9 > "x86, numa: Use near(er) online node instead of roundrobin for NUMA" > changed NUMA initialization on Intel to choose the nearest online node or > first node. Fake NUMA would be better of with round-robin initialization, > instead of the all CPUS on first node. Change the choice of first node, back > to round-robin. > Why would fake NUMA "be better off with round-robin initialization"? > > --- > > diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c > index 85f69cd..47dd171 100644 > --- a/arch/x86/kernel/cpu/intel.c > +++ b/arch/x86/kernel/cpu/intel.c > @@ -283,9 +283,7 @@ static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c) > /* Don't do the funky fallback heuristics the AMD version employs > for now. */ > node = apicid_to_node[apicid]; > - if (node == NUMA_NO_NODE) > - node = first_node(node_online_map); > - else if (!node_online(node)) { > + if (node == NUMA_NO_NODE || !node_online(node)) { > /* reuse the value from init_cpu_to_node() */ > node = cpu_to_node(cpu); > } > -- > 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/