Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933477AbcK1OeF (ORCPT ); Mon, 28 Nov 2016 09:34:05 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:35891 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933063AbcK1Odf (ORCPT ); Mon, 28 Nov 2016 09:33:35 -0500 Date: Mon, 28 Nov 2016 15:33:32 +0100 From: Michal Hocko To: Naoya Horiguchi Cc: linux-mm@kvack.org, "Kirill A. Shutemov" , Hugh Dickins , Andrew Morton , Dave Hansen , Andrea Arcangeli , Mel Gorman , Vlastimil Babka , Pavel Emelyanov , Zi Yan , Balbir Singh , linux-kernel@vger.kernel.org, Naoya Horiguchi Subject: Re: [PATCH v2 06/12] mm: thp: enable thp migration in generic path Message-ID: <20161128143331.GO14788@dhcp22.suse.cz> References: <1478561517-4317-1-git-send-email-n-horiguchi@ah.jp.nec.com> <1478561517-4317-7-git-send-email-n-horiguchi@ah.jp.nec.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1478561517-4317-7-git-send-email-n-horiguchi@ah.jp.nec.com> User-Agent: Mutt/1.6.0 (2016-04-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 626 Lines: 13 On Tue 08-11-16 08:31:51, Naoya Horiguchi wrote: > This patch makes it possible to support thp migration gradually. If you fail > to allocate a destination page as a thp, you just split the source thp as we > do now, and then enter the normal page migration. If you succeed to allocate > destination thp, you enter thp migration. Subsequent patches actually enable > thp migration for each caller of page migration by allowing its get_new_page() > callback to allocate thps. Does this need to be in a separate patch? Wouldn't it make more sense to have the full THP migration code in a single one? -- Michal Hocko SUSE Labs