From mboxrd@z Thu Jan 1 00:00:00 1970 From: m.nazarewicz@samsung.com (=?utf-8?B?TWljaGHFgiBOYXphcmV3aWN6?=) Date: Fri, 29 Oct 2010 16:58:31 +0200 Subject: [RFC][PATCH 0/3] big chunk memory allocator v2 In-Reply-To: <20101029142741.GB19823@gargoyle.fritz.box> References: <20101026190042.57f30338.kamezawa.hiroyu@jp.fujitsu.com> <20101029103154.GA10823@gargoyle.fritz.box> <20101029195900.88559162.kamezawa.hiroyu@jp.fujitsu.com> <20101029122928.GA17792@gargoyle.fritz.box> <20101029142741.GB19823@gargoyle.fritz.box> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, 29 Oct 2010 16:27:41 +0200, Andi Kleen wrote: > On Fri, Oct 29, 2010 at 01:43:51PM +0100, Micha? Nazarewicz wrote: >> Hmm... true. Still the point remains that only movable and reclaimable pages are >> allowed in the marked regions. This in effect means that from unmovable pages >> point of view, the area is unusable but I havn't thought of any other way to >> guarantee that because of fragmentation, long sequence of free/movable/reclaimable >> pages is available. > Essentially a movable zone as defined today. Ah, right, I somehow was under the impresion that movable zone can be used as a fallback zone. When I'm finished with my current approach I'll look more closely into it. > That gets you near all the problems of highmem (except for the mapping > problem and you're a bit more flexible in the splits): > > Someone has to decide at boot how much should be movable > and what not, some workloads will run out of space, some may > deadlock when it runs out of management objects, etc.etc. > Classic highmem had a long string of issues with all of this. Here's where the rest of CMA comes. The solution may be not perfect but it's probably better then nothing. The idea is to define regions for each device (with possibility for a single region to be shared) which, hopefuly, can help with fragmentation. In the current form, CMA is designed mostly for embeded systems where one can define what kind of devices will be used, but in general this could be used for other systems as well. -- Best regards, _ _ | Humble Liege of Serenely Enlightened Majesty of o' \,=./ `o | Computer Science, Micha? "mina86" Nazarewicz (o o) +----[mina86*mina86.com]---[mina86*jabber.org]----ooO--(_)--Ooo-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933926Ab0J2O4M (ORCPT ); Fri, 29 Oct 2010 10:56:12 -0400 Received: from mailout3.w1.samsung.com ([210.118.77.13]:27933 "EHLO mailout3.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757398Ab0J2O4J convert rfc822-to-8bit (ORCPT ); Fri, 29 Oct 2010 10:56:09 -0400 MIME-version: 1.0 Content-type: text/plain; charset=utf-8; format=flowed; delsp=yes Date: Fri, 29 Oct 2010 16:58:31 +0200 From: =?utf-8?B?TWljaGHFgiBOYXphcmV3aWN6?= Subject: Re: [RFC][PATCH 0/3] big chunk memory allocator v2 In-reply-to: <20101029142741.GB19823@gargoyle.fritz.box> To: Andi Kleen Cc: KAMEZAWA Hiroyuki , Minchan Kim , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , KOSAKI Motohiro , "fujita.tomonori@lab.ntt.co.jp" , "felipe.contreras@gmail.com" , linux-arm-kernel , Jonathan Corbet , Russell King , Pawel Osciak , Peter Zijlstra Message-id: Organization: Samsung Electronics Content-transfer-encoding: 8BIT User-Agent: Opera Mail/10.62 (Linux) References: <20101026190042.57f30338.kamezawa.hiroyu@jp.fujitsu.com> <20101029103154.GA10823@gargoyle.fritz.box> <20101029195900.88559162.kamezawa.hiroyu@jp.fujitsu.com> <20101029122928.GA17792@gargoyle.fritz.box> <20101029142741.GB19823@gargoyle.fritz.box> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 29 Oct 2010 16:27:41 +0200, Andi Kleen wrote: > On Fri, Oct 29, 2010 at 01:43:51PM +0100, Michał Nazarewicz wrote: >> Hmm... true. Still the point remains that only movable and reclaimable pages are >> allowed in the marked regions. This in effect means that from unmovable pages >> point of view, the area is unusable but I havn't thought of any other way to >> guarantee that because of fragmentation, long sequence of free/movable/reclaimable >> pages is available. > Essentially a movable zone as defined today. Ah, right, I somehow was under the impresion that movable zone can be used as a fallback zone. When I'm finished with my current approach I'll look more closely into it. > That gets you near all the problems of highmem (except for the mapping > problem and you're a bit more flexible in the splits): > > Someone has to decide at boot how much should be movable > and what not, some workloads will run out of space, some may > deadlock when it runs out of management objects, etc.etc. > Classic highmem had a long string of issues with all of this. Here's where the rest of CMA comes. The solution may be not perfect but it's probably better then nothing. The idea is to define regions for each device (with possibility for a single region to be shared) which, hopefuly, can help with fragmentation. In the current form, CMA is designed mostly for embeded systems where one can define what kind of devices will be used, but in general this could be used for other systems as well. -- Best regards, _ _ | Humble Liege of Serenely Enlightened Majesty of o' \,=./ `o | Computer Science, Michał "mina86" Nazarewicz (o o) +----[mina86*mina86.com]---[mina86*jabber.org]----ooO--(_)--Ooo-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id D69A56B0088 for ; Fri, 29 Oct 2010 10:56:09 -0400 (EDT) Received: from eu_spt1 (mailout1.w1.samsung.com [210.118.77.11]) by mailout1.w1.samsung.com (iPlanet Messaging Server 5.2 Patch 2 (built Jul 14 2004)) with ESMTP id <0LB2001KS45IZI@mailout1.w1.samsung.com> for linux-mm@kvack.org; Fri, 29 Oct 2010 15:56:07 +0100 (BST) Received: from linux.samsung.com ([106.116.38.10]) by spt1.w1.samsung.com (iPlanet Messaging Server 5.2 Patch 2 (built Jul 14 2004)) with ESMTPA id <0LB200CTT45I0E@spt1.w1.samsung.com> for linux-mm@kvack.org; Fri, 29 Oct 2010 15:56:06 +0100 (BST) Date: Fri, 29 Oct 2010 16:58:31 +0200 From: =?utf-8?B?TWljaGHFgiBOYXphcmV3aWN6?= Subject: Re: [RFC][PATCH 0/3] big chunk memory allocator v2 In-reply-to: <20101029142741.GB19823@gargoyle.fritz.box> Message-id: MIME-version: 1.0 Content-type: text/plain; charset=utf-8; format=flowed; delsp=yes Content-transfer-encoding: Quoted-Printable References: <20101026190042.57f30338.kamezawa.hiroyu@jp.fujitsu.com> <20101029103154.GA10823@gargoyle.fritz.box> <20101029195900.88559162.kamezawa.hiroyu@jp.fujitsu.com> <20101029122928.GA17792@gargoyle.fritz.box> <20101029142741.GB19823@gargoyle.fritz.box> Sender: owner-linux-mm@kvack.org To: Andi Kleen Cc: KAMEZAWA Hiroyuki , Minchan Kim , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , KOSAKI Motohiro , "fujita.tomonori@lab.ntt.co.jp" , "felipe.contreras@gmail.com" , linux-arm-kernel , Jonathan Corbet , Russell King , Pawel Osciak , Peter Zijlstra List-ID: On Fri, 29 Oct 2010 16:27:41 +0200, Andi Kleen wr= ote: > On Fri, Oct 29, 2010 at 01:43:51PM +0100, Micha=C5=82 Nazarewicz wrote= : >> Hmm... true. Still the point remains that only movable and reclaimab= le pages are >> allowed in the marked regions. This in effect means that from unmova= ble pages >> point of view, the area is unusable but I havn't thought of any other= way to >> guarantee that because of fragmentation, long sequence of free/movabl= e/reclaimable >> pages is available. > Essentially a movable zone as defined today. Ah, right, I somehow was under the impresion that movable zone can be us= ed as a fallback zone. When I'm finished with my current approach I'll look more closely= into it. > That gets you near all the problems of highmem (except for the mapping= > problem and you're a bit more flexible in the splits): > > Someone has to decide at boot how much should be movable > and what not, some workloads will run out of space, some may > deadlock when it runs out of management objects, etc.etc. > Classic highmem had a long string of issues with all of this. Here's where the rest of CMA comes. The solution may be not perfect but= it's probably better then nothing. The idea is to define regions for each de= vice (with possibility for a single region to be shared) which, hopefuly, can= help with fragmentation. In the current form, CMA is designed mostly for embeded systems where on= e can define what kind of devices will be used, but in general this could be u= sed for other systems as well. -- = Best regards, _ _ | Humble Liege of Serenely Enlightened Majesty of o' \,=3D./ `o | Computer Science, Micha=C5=82 "mina86" Nazarewicz (o o) +----[mina86*mina86.com]---[mina86*jabber.org]----ooO--(_)--Ooo-- -- 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