From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id 80B466B0044 for ; Wed, 28 Oct 2009 05:03:51 -0400 (EDT) Received: from zps37.corp.google.com (zps37.corp.google.com [172.25.146.37]) by smtp-out.google.com with ESMTP id n9S93lWD001638 for ; Wed, 28 Oct 2009 02:03:47 -0700 Received: from pwj8 (pwj8.prod.google.com [10.241.219.72]) by zps37.corp.google.com with ESMTP id n9S93iJt025473 for ; Wed, 28 Oct 2009 02:03:45 -0700 Received: by pwj8 with SMTP id 8so719605pwj.3 for ; Wed, 28 Oct 2009 02:03:44 -0700 (PDT) Date: Wed, 28 Oct 2009 02:03:41 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH v2 1/5] mm: add numa node symlink for memory section in sysfs In-Reply-To: <20091028083137.GA24140@osiris.boeblingen.de.ibm.com> Message-ID: References: <20091022040814.15705.95572.stgit@bob.kio> <20091022041510.15705.5410.stgit@bob.kio> <20091027195907.GJ14102@ldl.fc.hp.com> <20091028083137.GA24140@osiris.boeblingen.de.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Heiko Carstens Cc: Alex Chiang , Andrew Morton , Gary Hade , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Badari Pulavarty , Martin Schwidefsky , Ingo Molnar List-ID: On Wed, 28 Oct 2009, Heiko Carstens wrote: > The short answer is: s390 doesn't support NUMA, because the hardware doesn't > tell us to which node (book in s390 terms) a memory range belongs to. > > Memory layout for a logical partition is striped: first x mbyte belong to > node 0, next x mbyte belong to node 1, etc... > > Also, since there is always a hypervisor running below Linux I don't think > it would make too much sense if we would know to which node a piece of > memory belongs to: if the hypervisor decides to schedule a virtual cpu of > a logical partition to a different node then what? > Ok, so the patchset is a no-op for s390 since it only utilizes the !CONFIG_NUMA code. Alex, I think the safest thing to do in unregister_mem_sect_under_nodes() is to iterate though the section pfns and remove links to the node_device kobjs for all the distinct pfn_to_nid()'s that it encounters. -- 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