From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx179.postini.com [74.125.245.179]) by kanga.kvack.org (Postfix) with SMTP id 3275D6B0071 for ; Wed, 4 Jul 2012 06:49:55 -0400 (EDT) Message-ID: <4FF41FF2.1010600@cn.fujitsu.com> Date: Wed, 04 Jul 2012 18:50:26 +0800 From: Lai Jiangshan MIME-Version: 1.0 Subject: Re: [RFC PATCH 2/3 V1] mm, page migrate: add MIGRATE_HOTREMOVE type References: <1341386778-8002-1-git-send-email-laijs@cn.fujitsu.com> <1341386778-8002-3-git-send-email-laijs@cn.fujitsu.com> <20120704101942.GM13141@csn.ul.ie> In-Reply-To: <20120704101942.GM13141@csn.ul.ie> Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Chris Metcalf , Len Brown , Greg Kroah-Hartman , Andi Kleen , Julia Lawall , David Howells , Benjamin Herrenschmidt , Kay Sievers , Ingo Molnar , Paul Gortmaker , Daniel Kiper , Andrew Morton , Konrad Rzeszutek Wilk , Michal Hocko , KAMEZAWA Hiroyuki , Minchan Kim , Michal Nazarewicz , Marek Szyprowski , Rik van Riel , Bjorn Helgaas , Christoph Lameter , David Rientjes , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org On 07/04/2012 06:19 PM, Mel Gorman wrote: > On Wed, Jul 04, 2012 at 03:26:17PM +0800, Lai Jiangshan wrote: >> MIGRATE_HOTREMOVE is a special kind of MIGRATE_MOVABLE, but it is stable: >> any page of the type can NOT be changed to the other type nor be moved to >> the other free list. >> >> So the pages of MIGRATE_HOTREMOVE are always movable, this ability is >> useful for hugepages and hotremove ...etc. >> >> MIGRATE_HOTREMOVE pages is the used as the first candidate when >> we allocate movable pages. >> >> 1) add small routine is_migrate_movable() for movable-like types >> 2) add small routine is_migrate_stable() for stable types >> 3) fix some comments >> 4) fix get_any_page(). The get_any_page() may change >> MIGRATE_CMA/HOTREMOVE types page to MOVABLE which may cause this page >> to be changed to UNMOVABLE. >> > > Reuse MIGRATE_CMA. Will do it. > Even if the pages are on the movable lists it should > not be a problem for memory hot-remove. It does have problem, unmovable pages may be allocated on it. The movable lists can be used for other type when ohter type is empty. Or we can rename current movable-lists to movable-preference-lists. Thanks, Lai -- 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