From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f182.google.com (mail-io0-f182.google.com [209.85.223.182]) by kanga.kvack.org (Postfix) with ESMTP id 21AF66B0038 for ; Thu, 17 Dec 2015 00:02:27 -0500 (EST) Received: by mail-io0-f182.google.com with SMTP id q126so43473034iof.2 for ; Wed, 16 Dec 2015 21:02:27 -0800 (PST) Received: from mgwkm03.jp.fujitsu.com (mgwkm03.jp.fujitsu.com. [202.219.69.170]) by mx.google.com with ESMTPS id e17si4889607ioj.6.2015.12.16.21.02.25 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 16 Dec 2015 21:02:26 -0800 (PST) Received: from m3050.s.css.fujitsu.com (msm.b.css.fujitsu.com [10.134.21.208]) by kw-mxq.gw.nic.fujitsu.com (Postfix) with ESMTP id 5A242AC015E for ; Thu, 17 Dec 2015 14:02:20 +0900 (JST) Subject: Re: [PATCH v3 2/2] mm: Introduce kernelcore=mirror option References: <1449631109-14756-1-git-send-email-izumi.taku@jp.fujitsu.com> <1449631177-14863-1-git-send-email-izumi.taku@jp.fujitsu.com> <56679FDC.1080800@huawei.com> <3908561D78D1C84285E8C5FCA982C28F39F7F4CD@ORSMSX114.amr.corp.intel.com> <5668D1FA.4050108@huawei.com> <56691819.3040105@huawei.com> <566A9AE1.7020001@huawei.com> <56722258.6030800@huawei.com> <567223A7.9090407@jp.fujitsu.com> <56723E8B.8050201@huawei.com> From: Kamezawa Hiroyuki Message-ID: <567241BE.5030806@jp.fujitsu.com> Date: Thu, 17 Dec 2015 14:01:50 +0900 MIME-Version: 1.0 In-Reply-To: <56723E8B.8050201@huawei.com> Content-Type: text/plain; charset=iso-2022-jp Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Xishi Qiu Cc: "Izumi, Taku" , "Luck, Tony" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "akpm@linux-foundation.org" , "mel@csn.ul.ie" , "Hansen, Dave" , "matt@codeblueprint.co.uk" On 2015/12/17 13:48, Xishi Qiu wrote: > On 2015/12/17 10:53, Kamezawa Hiroyuki wrote: > >> On 2015/12/17 11:47, Xishi Qiu wrote: >>> On 2015/12/17 9:38, Izumi, Taku wrote: >>> >>>> Dear Xishi, >>>> >>>> Sorry for late. >>>> >>>>> -----Original Message----- >>>>> From: Xishi Qiu [mailto:qiuxishi@huawei.com] >>>>> Sent: Friday, December 11, 2015 6:44 PM >>>>> To: Izumi, Taku/泉 拓 >>>>> Cc: Luck, Tony; linux-kernel@vger.kernel.org; linux-mm@kvack.org; akpm@linux-foundation.org; Kamezawa, Hiroyuki/亀澤 寛 >>>>> 之; mel@csn.ul.ie; Hansen, Dave; matt@codeblueprint.co.uk >>>>> Subject: Re: [PATCH v3 2/2] mm: Introduce kernelcore=mirror option >>>>> >>>>> On 2015/12/11 13:53, Izumi, Taku wrote: >>>>> >>>>>> Dear Xishi, >>>>>> >>>>>>> Hi Taku, >>>>>>> >>>>>>> Whether it is possible that we rewrite the fallback function in buddy system >>>>>>> when zone_movable and mirrored_kernelcore are both enabled? >>>>>> >>>>>> What does "when zone_movable and mirrored_kernelcore are both enabled?" mean ? >>>>>> >>>>>> My patchset just provides a new way to create ZONE_MOVABLE. >>>>>> >>>>> >>>>> Hi Taku, >>>>> >>> >>> Hi Taku, >>> >>> We can NOT specify kernelcore= "nn[KMG]" and "mirror" at the same time. >>> So when we use "mirror", in fact, the movable zone is a new zone. I think it is >>> more appropriate with this name "mirrored zone", and also we can rewrite the >>> fallback function in buddy system in this case. >> >> kernelcore ="mirrored zone" ? > > No, it's zone_names[MAX_NR_ZONES] > How about "Movable", -> "Non-mirrored"? > That will break many user apps. I think we don't have enough reason. >> >> BTW, let me confirm. >> >> ZONE_NORMAL = mirrored >> ZONE_MOVABLE = not mirrored. >> > > Yes, > >> so, the new zone is "not-mirrored" zone. >> >> Now, fallback function is >> >> movable -> normal -> DMA. >> >> As Tony requested, we may need a knob to stop a fallback in "movable->normal", later. >> > > If the mirrored memory is small and the other is large, > I think we can both enable "non-mirrored -> normal" and "normal -> non-mirrored". Size of mirrored memory can be configured by software(EFI var). So, having both is just overkill and normal->non-mirroed fallback is meaningless considering what the feature want to guarantee. Thanks, -Kame -- 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