From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751672AbcGRHpZ (ORCPT ); Mon, 18 Jul 2016 03:45:25 -0400 Received: from mx2.suse.de ([195.135.220.15]:46776 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751398AbcGRHpY (ORCPT ); Mon, 18 Jul 2016 03:45:24 -0400 Subject: Re: [PATCH 1/2] mem-hotplug: use GFP_HIGHUSER_MOVABLE in, alloc_migrate_target() To: Joonsoo Kim , Xishi Qiu References: <57884EAA.9030603@huawei.com> <20160718055150.GF9460@js1304-P5Q-DELUXE> Cc: David Rientjes , Andrew Morton , Naoya Horiguchi , Linux MM , LKML From: Vlastimil Babka Message-ID: Date: Mon, 18 Jul 2016 09:45:20 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.1.1 MIME-Version: 1.0 In-Reply-To: <20160718055150.GF9460@js1304-P5Q-DELUXE> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/18/2016 07:51 AM, Joonsoo Kim wrote: > On Fri, Jul 15, 2016 at 10:47:06AM +0800, Xishi Qiu wrote: >> alloc_migrate_target() is called from migrate_pages(), and the page >> is always from user space, so we can add __GFP_HIGHMEM directly. > > No, all migratable pages are not from user space. For example, > blockdev file cache has __GFP_MOVABLE and migratable but it has no > __GFP_HIGHMEM and __GFP_USER. > > And, zram's memory isn't GFP_HIGHUSER_MOVABLE but has __GFP_MOVABLE. Right, and there's also Minchan's series for arbitrary driver page migration... > Thanks. > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f72.google.com (mail-wm0-f72.google.com [74.125.82.72]) by kanga.kvack.org (Postfix) with ESMTP id 9E2366B0261 for ; Mon, 18 Jul 2016 03:45:24 -0400 (EDT) Received: by mail-wm0-f72.google.com with SMTP id r190so52433626wmr.0 for ; Mon, 18 Jul 2016 00:45:24 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id a72si13343625wma.76.2016.07.18.00.45.23 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 18 Jul 2016 00:45:23 -0700 (PDT) Subject: Re: [PATCH 1/2] mem-hotplug: use GFP_HIGHUSER_MOVABLE in, alloc_migrate_target() References: <57884EAA.9030603@huawei.com> <20160718055150.GF9460@js1304-P5Q-DELUXE> From: Vlastimil Babka Message-ID: Date: Mon, 18 Jul 2016 09:45:20 +0200 MIME-Version: 1.0 In-Reply-To: <20160718055150.GF9460@js1304-P5Q-DELUXE> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Joonsoo Kim , Xishi Qiu Cc: David Rientjes , Andrew Morton , Naoya Horiguchi , Linux MM , LKML On 07/18/2016 07:51 AM, Joonsoo Kim wrote: > On Fri, Jul 15, 2016 at 10:47:06AM +0800, Xishi Qiu wrote: >> alloc_migrate_target() is called from migrate_pages(), and the page >> is always from user space, so we can add __GFP_HIGHMEM directly. > > No, all migratable pages are not from user space. For example, > blockdev file cache has __GFP_MOVABLE and migratable but it has no > __GFP_HIGHMEM and __GFP_USER. > > And, zram's memory isn't GFP_HIGHUSER_MOVABLE but has __GFP_MOVABLE. Right, and there's also Minchan's series for arbitrary driver page migration... > 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