Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932242AbcKJKbd (ORCPT ); Thu, 10 Nov 2016 05:31:33 -0500 Received: from mail-pf0-f194.google.com ([209.85.192.194]:33977 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754563AbcKJKbb (ORCPT ); Thu, 10 Nov 2016 05:31:31 -0500 Subject: Re: [PATCH v2 09/12] mm: hwpoison: soft offline supports thp migration To: Naoya Horiguchi , linux-mm@kvack.org References: <1478561517-4317-1-git-send-email-n-horiguchi@ah.jp.nec.com> <1478561517-4317-10-git-send-email-n-horiguchi@ah.jp.nec.com> Cc: "Kirill A. Shutemov" , Hugh Dickins , Andrew Morton , Dave Hansen , Andrea Arcangeli , Mel Gorman , Michal Hocko , Vlastimil Babka , Pavel Emelyanov , Zi Yan , linux-kernel@vger.kernel.org, Naoya Horiguchi From: Balbir Singh Message-ID: <6e9aa943-31ea-5b08-8459-2e6a85940546@gmail.com> Date: Thu, 10 Nov 2016 21:31:10 +1100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <1478561517-4317-10-git-send-email-n-horiguchi@ah.jp.nec.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1177 Lines: 32 On 08/11/16 10:31, Naoya Horiguchi wrote: > This patch enables thp migration for soft offline. > > Signed-off-by: Naoya Horiguchi > --- > mm/memory-failure.c | 31 ++++++++++++------------------- > 1 file changed, 12 insertions(+), 19 deletions(-) > > diff --git v4.9-rc2-mmotm-2016-10-27-18-27/mm/memory-failure.c v4.9-rc2-mmotm-2016-10-27-18-27_patched/mm/memory-failure.c > index 19e796d..6cc8157 100644 > --- v4.9-rc2-mmotm-2016-10-27-18-27/mm/memory-failure.c > +++ v4.9-rc2-mmotm-2016-10-27-18-27_patched/mm/memory-failure.c > @@ -1485,7 +1485,17 @@ static struct page *new_page(struct page *p, unsigned long private, int **x) > if (PageHuge(p)) > return alloc_huge_page_node(page_hstate(compound_head(p)), > nid); > - else > + else if (thp_migration_supported() && PageTransHuge(p)) { > + struct page *thp; > + > + thp = alloc_pages_node(nid, > + (GFP_TRANSHUGE | __GFP_THISNODE) & ~__GFP_RECLAIM, > + HPAGE_PMD_ORDER); > + if (!thp) > + return NULL; Just wondering if new_page() fails, migration of that entry fails. Do we then split and migrate? I guess this applies to THP migration in general. Balbir Singh