From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f51.google.com (mail-wm0-f51.google.com [74.125.82.51]) by kanga.kvack.org (Postfix) with ESMTP id A93B96B0038 for ; Thu, 19 Nov 2015 11:44:16 -0500 (EST) Received: by wmec201 with SMTP id c201so34848397wme.0 for ; Thu, 19 Nov 2015 08:44:16 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id gd4si12409270wjb.2.2015.11.19.08.44.15 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 19 Nov 2015 08:44:15 -0800 (PST) Subject: Re: [PATCH 3/5] mm, page_owner: copy page owner info during migration References: <1446649261-27122-1-git-send-email-vbabka@suse.cz> <1446649261-27122-4-git-send-email-vbabka@suse.cz> From: Vlastimil Babka Message-ID: <564DFC5C.2090103@suse.cz> Date: Thu, 19 Nov 2015 17:44:12 +0100 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Hugh Dickins Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Joonsoo Kim , Minchan Kim , Sasha Levin , "Kirill A. Shutemov" , Mel Gorman On 11/08/2015 10:29 PM, Hugh Dickins wrote: > > Would it be possible to move that line into migrate_page_copy()? > > I don't think it's wrong where you placed it, but that block is really > about resetting the old page ready for freeing, and I'd prefer to keep > all the transference of properties from old to new in migrate_page_copy() > if we can. OK, makes sense, will do in v2. > But check how that behaves in the migrate_misplaced_transhuge_page() > case: I haven't studied long enough, but I think you may have been missing > to copy_page_owner in that case; You're right, I missed that path :/ > but beware of its "fail_putback", which > for some things nastily entails undoing what's already been done. Yeah, I think I don't need to reset page owner info in the fail_putback path, for the same reason I don't reset it from the old page when migration is successful. The page is going to be freed anyway, and if it somehow hits a bug before that, we will still have something to print (after patch 5). Thanks! -- 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