Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934915AbaGXXco (ORCPT ); Thu, 24 Jul 2014 19:32:44 -0400 Received: from e8.ny.us.ibm.com ([32.97.182.138]:39986 "EHLO e8.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934568AbaGXXcm (ORCPT ); Thu, 24 Jul 2014 19:32:42 -0400 Date: Thu, 24 Jul 2014 16:32:30 -0700 From: Nishanth Aravamudan To: Jiang Liu Cc: Tony Luck , Andrew Morton , Mel Gorman , David Rientjes , Mike Galbraith , Peter Zijlstra , "Rafael J . Wysocki" , "linux-mm@kvack.org" , linux-hotplug@vger.kernel.org, Linux Kernel Mailing List Subject: Re: [RFC Patch V1 00/30] Enable memoryless node on x86 platforms Message-ID: <20140724233230.GD24458@linux.vnet.ibm.com> References: <1405064267-11678-1-git-send-email-jiang.liu@linux.intel.com> <20140721172331.GB4156@linux.vnet.ibm.com> <20140721175736.GG4156@linux.vnet.ibm.com> <53CF7048.20302@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <53CF7048.20302@linux.intel.com> X-Operating-System: Linux 3.13.0-32-generic (x86_64) User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14072423-0320-0000-0000-00000013476B Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 23.07.2014 [16:20:24 +0800], Jiang Liu wrote: > > > On 2014/7/22 1:57, Nishanth Aravamudan wrote: > > On 21.07.2014 [10:41:59 -0700], Tony Luck wrote: > >> On Mon, Jul 21, 2014 at 10:23 AM, Nishanth Aravamudan > >> wrote: > >>> It seems like the issue is the order of onlining of resources on a > >>> specific x86 platform? > >> > >> Yes. When we online a node the BIOS hits us with some ACPI hotplug events: > >> > >> First: Here are some new cpus > > > > Ok, so during this period, you might get some remote allocations. Do you > > know the topology of these CPUs? That is they belong to a > > (soon-to-exist) NUMA node? Can you online that currently offline NUMA > > node at this point (so that NODE_DATA()) resolves, etc.)? > Hi Nishanth, > We have method to get the NUMA information about the CPU, and > patch "[RFC Patch V1 30/30] x86, NUMA: Online node earlier when doing > CPU hot-addition" tries to solve this issue by onlining NUMA node > as early as possible. Actually we are trying to enable memoryless node > as you have suggested. Ok, it seems like you have two sets of patches then? One is to fix the NUMA information timing (30/30 only). The rest of the patches are general discussions about where cpu_to_mem() might be used instead of cpu_to_node(). However, based upon Tejun's feedback, it seems like rather than force all callers to use cpu_to_mem(), we should be looking at the core VM to ensure fallback is occuring appropriately when memoryless nodes are present. Do you have a specific situation, once you've applied 30/30, where kmalloc_node() leads to an Oops? Thanks, Nish -- 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/