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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DA894C43334 for ; Mon, 13 Jun 2022 06:05:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: List-Owner; bh=qqNviP9E+tKgwwAkmAa7ON01ZfDDwRdLk2zdRkehQq4=; b=tpJgSPElg5MHfz PTWWLFEPAOTVMmPBs9w+vL+ivU2M0eUwyl3rsjQumFSh/zsV1QSMQ4LRlUnLN2EhugJzh7ZBgLqRJ eex0THr6o+/zCluvQqY+/nEu59NhYKhi58dUvunx7wzy5sqt6xjo29hPSmnS0nSGQmzAbncKsVIw+ lTC0SM56ESNDBQMr/ieci5MQB55TrBrcx+d2L4zENC1M/2JuPBUtsmEFg9T6kqfRW04Zc3QZURKqK e+LkaKn2yUc3BTpGJt6a8XoaiKCPLFW+xhBVGhLE69gRZjnEMAlSvrIQUzcKQQr0I6Sfm9jCepo6g c3nQvgkbB5Nf1NzRbLHQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1o0dBE-001aTd-DA; Mon, 13 Jun 2022 06:04:04 +0000 Received: from szxga08-in.huawei.com ([45.249.212.255]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1o0dBA-001aQj-Go for linux-arm-kernel@lists.infradead.org; Mon, 13 Jun 2022 06:04:02 +0000 Received: from kwepemi100012.china.huawei.com (unknown [172.30.72.55]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4LM1DC6jqXz1K9Nw; Mon, 13 Jun 2022 14:01:47 +0800 (CST) Received: from kwepemi500016.china.huawei.com (7.221.188.220) by kwepemi100012.china.huawei.com (7.221.188.202) 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 14:03:42 +0800 Received: from kwepemi500016.china.huawei.com ([7.221.188.220]) by kwepemi500016.china.huawei.com ([7.221.188.220]) with mapi id 15.01.2375.024; Mon, 13 Jun 2022 14:03:42 +0800 From: Zhouguanghui To: Anshuman Khandual , "akpm@linux-foundation.org" , "rppt@kernel.org" , "will@kernel.org" CC: "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "linux-arm-kernel@lists.infradead.org" , "xuqiang (M)" Subject: Re: [PATCH v3] memblock,arm64: Expand the static memblock memory table Thread-Topic: [PATCH v3] memblock,arm64: Expand the static memblock memory table Thread-Index: AQHYcatwg17tpfOKIU2lxCQfbCJwZA== Date: Mon, 13 Jun 2022 06:03:42 +0000 Message-ID: References: <20220527091832.63489-1-zhouguanghui1@huawei.com> Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.174.178.157] MIME-Version: 1.0 X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220612_230400_949748_6F9E6CDC X-CRM114-Status: GOOD ( 19.90 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-2022-jp" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 在 2022/6/7 14:43, Anshuman Khandual 写道: > Hello Zhou, > > On 5/27/22 14:48, Zhou Guanghui wrote: >> In a system using HBM, a multi-bit ECC error occurs, and the BIOS >> will mark the corresponding area (for example, 2 MB) as unusable. >> When the system restarts next time, these areas are not reported >> or reported as EFI_UNUSABLE_MEMORY. Both cases lead to an increase >> in the number of memblocks, whereas EFI_UNUSABLE_MEMORY leads to a >> larger number of memblocks. >> >> For example, if the EFI_UNUSABLE_MEMORY type is reported: >> ... >> memory[0x92] [0x0000200834a00000-0x0000200835bfffff], 0x0000000001200000 bytes on node 7 flags: 0x0 >> memory[0x93] [0x0000200835c00000-0x0000200835dfffff], 0x0000000000200000 bytes on node 7 flags: 0x4 >> memory[0x94] [0x0000200835e00000-0x00002008367fffff], 0x0000000000a00000 bytes on node 7 flags: 0x0 >> memory[0x95] [0x0000200836800000-0x00002008369fffff], 0x0000000000200000 bytes on node 7 flags: 0x4 >> memory[0x96] [0x0000200836a00000-0x0000200837bfffff], 0x0000000001200000 bytes on node 7 flags: 0x0 >> memory[0x97] [0x0000200837c00000-0x0000200837dfffff], 0x0000000000200000 bytes on node 7 flags: 0x4 >> memory[0x98] [0x0000200837e00000-0x000020087fffffff], 0x0000000048200000 bytes on node 7 flags: 0x0 >> memory[0x99] [0x0000200880000000-0x0000200bcfffffff], 0x0000000350000000 bytes on node 6 flags: 0x0 >> memory[0x9a] [0x0000200bd0000000-0x0000200bd01fffff], 0x0000000000200000 bytes on node 6 flags: 0x4 >> memory[0x9b] [0x0000200bd0200000-0x0000200bd07fffff], 0x0000000000600000 bytes on node 6 flags: 0x0 >> memory[0x9c] [0x0000200bd0800000-0x0000200bd09fffff], 0x0000000000200000 bytes on node 6 flags: 0x4 >> memory[0x9d] [0x0000200bd0a00000-0x0000200fcfffffff], 0x00000003ff600000 bytes on node 6 flags: 0x0 >> memory[0x9e] [0x0000200fd0000000-0x0000200fd01fffff], 0x0000000000200000 bytes on node 6 flags: 0x4 >> memory[0x9f] [0x0000200fd0200000-0x0000200fffffffff], 0x000000002fe00000 bytes on node 6 flags: 0x0 >> ... > > Although this patch did not mention about a real world system requiring > this support, as been reported on the thread, Ampere Altra does seem to > get benefited. Regardless, it's always better to describe platform test > scenarios in more detail. > I encountered this scenario on Huawei Ascend ARM64 SoC. >> >> The EFI memory map is parsed to construct the memblock arrays before >> the memblock arrays can be resized. As the result, memory regions >> beyond INIT_MEMBLOCK_REGIONS are lost. >> >> Allow overriding memblock.memory array size with architecture defined >> INIT_MEMBLOCK_MEMORY_REGIONS and make arm64 to set >> INIT_MEMBLOCK_MEMORY_REGIONS to 1024 when CONFIG_EFI is enabled. > > Right, but first this needs to mention that INIT_MEMBLOCK_MEMORY_REGIONS > (new macro) is being added to replace INIT_MEMBLOCK_REGIONS, representing > max memory regions in the memblock. Platform override comes afterwards. > Add a paragraph before the description,like this? Add a new macro INIT_MEMBLOCK_MEMORY_REGTIONS to replace INIT_MEMBLOCK_REGTIONS to define the size of the static memblock.memory array. >> >> Signed-off-by: Zhou Guanghui >> Acked-by: Mike Rapoport >> --- >> arch/arm64/include/asm/memory.h | 9 +++++++++ >> mm/memblock.c | 14 +++++++++----- >> 2 files changed, 18 insertions(+), 5 deletions(-) >> >> diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h >> index 0af70d9abede..eda61c0389c4 100644 >> --- a/arch/arm64/include/asm/memory.h >> +++ b/arch/arm64/include/asm/memory.h >> @@ -364,6 +364,15 @@ void dump_mem_limit(void); >> # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1) >> #endif >> >> +/* >> + * memory regions which marked with flag MEMBLOCK_NOMAP may divide a continuous >> + * memory block into multiple parts. As a result, the number of memory regions >> + * is large. >> + */ > > As mentioned in the previous version's thread, > > This comment needs be more specific about this increased static array size, being > applicable ONLY for MEMBLOCK_NOMAP regions on EFI system with EFI_UNUSABLE_MEMORY > tagging/flag support. > EFI_UNUSABLE_MEMORY is only one type of the MEMBLOCK_NOMAP region, as shown in the is_usable_memory function. However, However, I currently have too many memblocks due to this flag. >> +#ifdef CONFIG_EFI >> +#define INIT_MEMBLOCK_MEMORY_REGIONS 1024 > > Although 1024 seems adequate as compared to 128 memory regions in the memblock to > handle such error scenarios, but a co-relation with INIT_MEMBLOCK_REGIONS would > be preferred similar to when INIT_MEMBLOCK_RESERVED_REGIONS gets overridden. This > avoid a precedence when random numbers could get assigned in other archs later on. > > $git grep INIT_MEMBLOCK_RESERVED_REGIONS arch/ > arch/arm64/include/asm/memory.h:# define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS + 1) > arch/loongarch/include/asm/sparsemem.h:#define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CPUS) > > Something like > > #define INIT_MEMBLOCK_MEMORY_REGIONS (INIT_MEMBLOCK_REGIONS * 8) > I don't think this is necessary because INIT_MEMBLOCK_REGIONS is not configurable. The newly added INIT_MEMBLOCK_MEMORY_REGIONS macro is customized for each platform. > > - Anshuman > Thanks! _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41E01C43334 for ; Mon, 13 Jun 2022 06:03:52 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B64B98D0154; Mon, 13 Jun 2022 02:03:51 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B138E8D0142; Mon, 13 Jun 2022 02:03:51 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9DB0D8D0154; Mon, 13 Jun 2022 02:03:51 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 8ED778D0142 for ; 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Mon, 13 Jun 2022 14:03:42 +0800 From: Zhouguanghui To: Anshuman Khandual , "akpm@linux-foundation.org" , "rppt@kernel.org" , "will@kernel.org" CC: "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "linux-arm-kernel@lists.infradead.org" , "xuqiang (M)" Subject: Re: [PATCH v3] memblock,arm64: Expand the static memblock memory table Thread-Topic: [PATCH v3] memblock,arm64: Expand the static memblock memory table Thread-Index: AQHYcatwg17tpfOKIU2lxCQfbCJwZA== Date: Mon, 13 Jun 2022 06:03:42 +0000 Message-ID: References: <20220527091832.63489-1-zhouguanghui1@huawei.com> Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.174.178.157] Content-Type: text/plain; charset="iso-2022-jp" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-CFilter-Loop: Reflected ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1655100231; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding:in-reply-to: references:references; bh=vRzpXt2ho4vBrVlNSxDyDUAuuWeRSInEPs6t/2ZTu7o=; b=JRJaA33h9jv6Ubfr51CU5XTgKzJ32eyhI7y7SkCqi33M2ei7jrHOzmJKFyg3qydu7qFc4b lTG0rIAkvSqWJ7EVtS0CtM7PsZR6q+dvRHrzIRGVnFBInLiqS7d5QlnYeFp38o0aGSZNn3 AicZYikVlhQ2g4h7W94xE72+05bLN/s= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1655100231; a=rsa-sha256; cv=none; b=LBmvBwcCQxeeMXIHQ1AvIZeC1lXowWCAf3zbDNugg+hc9Xx8qJ0sB1iSy/Rj/a2wnit48L 7vIW2GPSI9JiZxYadUTGXYC/qdUvB5ZPYDLIUQPArS79TBmuqnh7Nl6r38txNGZ4I+j9iw hBr2KinKCvvooLb8y+pWa+FB0wJ7WpQ= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf16.hostedemail.com: domain of zhouguanghui1@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=zhouguanghui1@huawei.com X-Rspamd-Server: rspam11 X-Rspam-User: Authentication-Results: imf16.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf16.hostedemail.com: domain of zhouguanghui1@huawei.com designates 45.249.212.255 as permitted sender) smtp.mailfrom=zhouguanghui1@huawei.com X-Stat-Signature: jfyn8sjd6p8amwozkny37eidrfszgpbt X-Rspamd-Queue-Id: 53CBB180084 X-HE-Tag: 1655100230-375802 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: =1B$B:_=1B(B 2022/6/7 14:43, Anshuman Khandual =1B$B Hello Zhou,=0A= > =0A= > On 5/27/22 14:48, Zhou Guanghui wrote:=0A= >> In a system using HBM, a multi-bit ECC error occurs, and the BIOS=0A= >> will mark the corresponding area (for example, 2 MB) as unusable.=0A= >> When the system restarts next time, these areas are not reported=0A= >> or reported as EFI_UNUSABLE_MEMORY. Both cases lead to an increase=0A= >> in the number of memblocks, whereas EFI_UNUSABLE_MEMORY leads to a=0A= >> larger number of memblocks.=0A= >>=0A= >> For example, if the EFI_UNUSABLE_MEMORY type is reported:=0A= >> ...=0A= >> memory[0x92] [0x0000200834a00000-0x0000200835bfffff], 0x0000000001200= 000 bytes on node 7 flags: 0x0=0A= >> memory[0x93] [0x0000200835c00000-0x0000200835dfffff], 0x0000000000200= 000 bytes on node 7 flags: 0x4=0A= >> memory[0x94] [0x0000200835e00000-0x00002008367fffff], 0x0000000000a00= 000 bytes on node 7 flags: 0x0=0A= >> memory[0x95] [0x0000200836800000-0x00002008369fffff], 0x0000000000200= 000 bytes on node 7 flags: 0x4=0A= >> memory[0x96] [0x0000200836a00000-0x0000200837bfffff], 0x0000000001200= 000 bytes on node 7 flags: 0x0=0A= >> memory[0x97] [0x0000200837c00000-0x0000200837dfffff], 0x0000000000200= 000 bytes on node 7 flags: 0x4=0A= >> memory[0x98] [0x0000200837e00000-0x000020087fffffff], 0x0000000048200= 000 bytes on node 7 flags: 0x0=0A= >> memory[0x99] [0x0000200880000000-0x0000200bcfffffff], 0x0000000350000= 000 bytes on node 6 flags: 0x0=0A= >> memory[0x9a] [0x0000200bd0000000-0x0000200bd01fffff], 0x0000000000200= 000 bytes on node 6 flags: 0x4=0A= >> memory[0x9b] [0x0000200bd0200000-0x0000200bd07fffff], 0x0000000000600= 000 bytes on node 6 flags: 0x0=0A= >> memory[0x9c] [0x0000200bd0800000-0x0000200bd09fffff], 0x0000000000200= 000 bytes on node 6 flags: 0x4=0A= >> memory[0x9d] [0x0000200bd0a00000-0x0000200fcfffffff], 0x00000003ff600= 000 bytes on node 6 flags: 0x0=0A= >> memory[0x9e] [0x0000200fd0000000-0x0000200fd01fffff], 0x0000000000200= 000 bytes on node 6 flags: 0x4=0A= >> memory[0x9f] [0x0000200fd0200000-0x0000200fffffffff], 0x000000002fe00= 000 bytes on node 6 flags: 0x0=0A= >> ...=0A= > =0A= > Although this patch did not mention about a real world system requiring= =0A= > this support, as been reported on the thread, Ampere Altra does seem to= =0A= > get benefited. Regardless, it's always better to describe platform test= =0A= > scenarios in more detail.=0A= > =0A= =0A= I encountered this scenario on Huawei Ascend ARM64 SoC.=0A= =0A= >>=0A= >> The EFI memory map is parsed to construct the memblock arrays before=0A= >> the memblock arrays can be resized. As the result, memory regions=0A= >> beyond INIT_MEMBLOCK_REGIONS are lost.=0A= >>=0A= >> Allow overriding memblock.memory array size with architecture defined=0A= >> INIT_MEMBLOCK_MEMORY_REGIONS and make arm64 to set=0A= >> INIT_MEMBLOCK_MEMORY_REGIONS to 1024 when CONFIG_EFI is enabled.=0A= > =0A= > Right, but first this needs to mention that INIT_MEMBLOCK_MEMORY_REGIONS= =0A= > (new macro) is being added to replace INIT_MEMBLOCK_REGIONS, representing= =0A= > max memory regions in the memblock. Platform override comes afterwards.= =0A= > =0A= =0A= Add a paragraph before the description,like this?=0A= =0A= Add a new macro INIT_MEMBLOCK_MEMORY_REGTIONS to replace =0A= INIT_MEMBLOCK_REGTIONS to define the size of the static memblock.memory =0A= array.=0A= =0A= >>=0A= >> Signed-off-by: Zhou Guanghui =0A= >> Acked-by: Mike Rapoport =0A= >> ---=0A= >> arch/arm64/include/asm/memory.h | 9 +++++++++=0A= >> mm/memblock.c | 14 +++++++++-----=0A= >> 2 files changed, 18 insertions(+), 5 deletions(-)=0A= >>=0A= >> diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/me= mory.h=0A= >> index 0af70d9abede..eda61c0389c4 100644=0A= >> --- a/arch/arm64/include/asm/memory.h=0A= >> +++ b/arch/arm64/include/asm/memory.h=0A= >> @@ -364,6 +364,15 @@ void dump_mem_limit(void);=0A= >> # define INIT_MEMBLOCK_RESERVED_REGIONS (INIT_MEMBLOCK_REGIONS + NR_CP= US + 1)=0A= >> #endif=0A= >> =0A= >> +/*=0A= >> + * memory regions which marked with flag MEMBLOCK_NOMAP may divide a co= ntinuous=0A= >> + * memory block into multiple parts. As a result, the number of memory = regions=0A= >> + * is large.=0A= >> + */=0A= > =0A= > As mentioned in the previous version's thread,=0A= > =0A= > This comment needs be more specific about this increased static array siz= e, being=0A= > applicable ONLY for MEMBLOCK_NOMAP regions on EFI system with EFI_UNUSABL= E_MEMORY=0A= > tagging/flag support.=0A= > =0A= =0A= EFI_UNUSABLE_MEMORY is only one type of the MEMBLOCK_NOMAP region, as =0A= shown in the is_usable_memory function. However, However, I currently =0A= have too many memblocks due to this flag.=0A= =0A= >> +#ifdef CONFIG_EFI=0A= >> +#define INIT_MEMBLOCK_MEMORY_REGIONS 1024=0A= > =0A= > Although 1024 seems adequate as compared to 128 memory regions in the mem= block to=0A= > handle such error scenarios, but a co-relation with INIT_MEMBLOCK_REGIONS= would=0A= > be preferred similar to when INIT_MEMBLOCK_RESERVED_REGIONS gets overridd= en. This=0A= > avoid a precedence when random numbers could get assigned in other archs = later on.=0A= > =0A= > $git grep INIT_MEMBLOCK_RESERVED_REGIONS arch/=0A= > arch/arm64/include/asm/memory.h:# define INIT_MEMBLOCK_RESERVED_REGIONS (= INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)=0A= > arch/loongarch/include/asm/sparsemem.h:#define INIT_MEMBLOCK_RESERVED_REG= IONS (INIT_MEMBLOCK_REGIONS + NR_CPUS)=0A= > =0A= > Something like=0A= > =0A= > #define INIT_MEMBLOCK_MEMORY_REGIONS (INIT_MEMBLOCK_REGIONS * 8)=0A= > =0A= =0A= I don't think this is necessary because INIT_MEMBLOCK_REGIONS is not =0A= configurable. The newly added INIT_MEMBLOCK_MEMORY_REGIONS macro is =0A= customized for each platform.=0A= =0A= > =0A= > - Anshuman=0A= > =0A= =0A= Thanks!=0A= =0A=