From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 49F71C433EF for ; Mon, 13 Jun 2022 09:15:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240803AbiFMJO1 (ORCPT ); Mon, 13 Jun 2022 05:14:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240840AbiFMJNj (ORCPT ); Mon, 13 Jun 2022 05:13:39 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DA6711146; Mon, 13 Jun 2022 02:13:37 -0700 (PDT) Received: from dggpemm500023.china.huawei.com (unknown [172.30.72.56]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4LM5Pk4sDyzRj0Y; Mon, 13 Jun 2022 17:10:18 +0800 (CST) Received: from dggpemm500014.china.huawei.com (7.185.36.153) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 13 Jun 2022 17:13:04 +0800 Received: from [10.174.178.120] (10.174.178.120) by dggpemm500014.china.huawei.com (7.185.36.153) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 13 Jun 2022 17:13:02 +0800 Message-ID: <590a1211-d316-d51d-6577-eb9983126dd0@huawei.com> Date: Mon, 13 Jun 2022 17:13:02 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.10.0 From: mawupeng Subject: Re: [PATCH v4 6/6] memblock: Disable mirror feature if kernelcore is not specified To: , , , CC: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , References: <20220613082147.183145-1-mawupeng1@huawei.com> <20220613082147.183145-7-mawupeng1@huawei.com> Content-Language: en-US In-Reply-To: <20220613082147.183145-7-mawupeng1@huawei.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.178.120] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpemm500014.china.huawei.com (7.185.36.153) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/13/2022 4:21 PM, Wupeng Ma wrote: > From: Ma Wupeng > > If system have some mirrored memory and mirrored feature is not specified > in boot parameter, the basic mirrored feature will be enabled and this will > lead to the following situations: > > - memblock memory allocation prefers mirrored region. This may have some > unexpected influence on numa affinity. > > - contiguous memory will be split into several parts if parts of them > is mirrored memory via memblock_mark_mirror(). > > To fix this, variable mirrored_kernelcore will be checked in > memblock_mark_mirror(). Mark mirrored memory with flag MEMBLOCK_MIRROR iff > kernelcore=mirror is added in the kernel parameters. > > Signed-off-by: Ma Wupeng > --- > mm/internal.h | 2 ++ > mm/memblock.c | 3 +++ > mm/page_alloc.c | 2 +- > 3 files changed, 6 insertions(+), 1 deletion(-) > > diff --git a/mm/internal.h b/mm/internal.h > index c0f8fbe0445b..ddd2d6a46f1b 100644 > --- a/mm/internal.h > +++ b/mm/internal.h > @@ -861,4 +861,6 @@ struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags); > > DECLARE_PER_CPU(struct per_cpu_nodestat, boot_nodestats); > > +extern bool mirrored_kernelcore; > + > #endif /* __MM_INTERNAL_H */ > diff --git a/mm/memblock.c b/mm/memblock.c > index b1d2a0009733..a9f18b988b7f 100644 > --- a/mm/memblock.c > +++ b/mm/memblock.c > @@ -924,6 +924,9 @@ int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size) > */ > int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size) > { > + if (!mirrored_kernelcore) > + return 0; > + > system_has_some_mirror = true; > > return memblock_setclr_flag(base, size, 1, MEMBLOCK_MIRROR); > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index e008a3df0485..9b030aeb4983 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -356,7 +356,7 @@ static unsigned long required_kernelcore_percent __initdata; > static unsigned long required_movablecore __initdata; > static unsigned long required_movablecore_percent __initdata; > static unsigned long zone_movable_pfn[MAX_NUMNODES] __initdata; > -static bool mirrored_kernelcore __meminitdata; > +bool mirrored_kernelcore __initdata; __initdata here is not suitable and will lead to compile warnings. In my test, __initdata_memblock and ro_after_init are both fine, but I am not sure which one to choose? Do you have any idea on this? > > /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */ > int movable_zone;