From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757247Ab2GQW3r (ORCPT ); Tue, 17 Jul 2012 18:29:47 -0400 Received: from mail-yw0-f46.google.com ([209.85.213.46]:47763 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757182Ab2GQW3p (ORCPT ); Tue, 17 Jul 2012 18:29:45 -0400 Date: Tue, 17 Jul 2012 15:29:43 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Andrew Morton cc: Joonsoo Kim , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Christoph Lameter , Mel Gorman Subject: Re: [PATCH] mm: fix wrong argument of migrate_huge_pages() in soft_offline_huge_page() In-Reply-To: <20120717134915.76adf9bd.akpm@linux-foundation.org> Message-ID: References: <1342544460-20095-1-git-send-email-js1304@gmail.com> <20120717134915.76adf9bd.akpm@linux-foundation.org> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 17 Jul 2012, Andrew Morton wrote: > > > Commit a6bc32b899223a877f595ef9ddc1e89ead5072b8 ('mm: compaction: introduce > > > sync-light migration for use by compaction') change declaration of > > > migrate_pages() and migrate_huge_pages(). > > > But, it miss changing argument of migrate_huge_pages() > > > in soft_offline_huge_page(). In this case, we should call with MIGRATE_SYNC. > > > So change it. > > > > > > Additionally, there is mismatch between type of argument and function > > > declaration for migrate_pages(). So fix this simple case, too. > > > > > > Signed-off-by: Joonsoo Kim > > > > Acked-by: David Rientjes > > > > Should be cc'd to stable for 3.3+. > > Well, why? I'm suspecting a switch from MIGRATE_SYNC_LIGHT to > MIGRATE_SYNC will have no discernable effect. Unless it triggers hitherto > unknkown about deadlocks... > > For a -stable backport we should have a description of the end-user > visible effects of the bug. This changelog lacked such a description. > I would put this: MIGRATE_SYNC_LIGHT will not aggressively attempt to defragment memory when allocating hugepages for migration with MIGRATE_SYNC_LIGHT, such as not defragmenting dirty pages, so MADV_SOFT_OFFLINE and /sys/devices/system/memory/soft_offline_page would be significantly less successful without this patch. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx150.postini.com [74.125.245.150]) by kanga.kvack.org (Postfix) with SMTP id 62CF06B005A for ; Tue, 17 Jul 2012 18:29:46 -0400 (EDT) Received: by ghrr18 with SMTP id r18so1206000ghr.14 for ; Tue, 17 Jul 2012 15:29:45 -0700 (PDT) Date: Tue, 17 Jul 2012 15:29:43 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH] mm: fix wrong argument of migrate_huge_pages() in soft_offline_huge_page() In-Reply-To: <20120717134915.76adf9bd.akpm@linux-foundation.org> Message-ID: References: <1342544460-20095-1-git-send-email-js1304@gmail.com> <20120717134915.76adf9bd.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Joonsoo Kim , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Christoph Lameter , Mel Gorman On Tue, 17 Jul 2012, Andrew Morton wrote: > > > Commit a6bc32b899223a877f595ef9ddc1e89ead5072b8 ('mm: compaction: introduce > > > sync-light migration for use by compaction') change declaration of > > > migrate_pages() and migrate_huge_pages(). > > > But, it miss changing argument of migrate_huge_pages() > > > in soft_offline_huge_page(). In this case, we should call with MIGRATE_SYNC. > > > So change it. > > > > > > Additionally, there is mismatch between type of argument and function > > > declaration for migrate_pages(). So fix this simple case, too. > > > > > > Signed-off-by: Joonsoo Kim > > > > Acked-by: David Rientjes > > > > Should be cc'd to stable for 3.3+. > > Well, why? I'm suspecting a switch from MIGRATE_SYNC_LIGHT to > MIGRATE_SYNC will have no discernable effect. Unless it triggers hitherto > unknkown about deadlocks... > > For a -stable backport we should have a description of the end-user > visible effects of the bug. This changelog lacked such a description. > I would put this: MIGRATE_SYNC_LIGHT will not aggressively attempt to defragment memory when allocating hugepages for migration with MIGRATE_SYNC_LIGHT, such as not defragmenting dirty pages, so MADV_SOFT_OFFLINE and /sys/devices/system/memory/soft_offline_page would be significantly less successful without this patch. -- 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