From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx145.postini.com [74.125.245.145]) by kanga.kvack.org (Postfix) with SMTP id AD7A36B0005 for ; Sun, 24 Feb 2013 22:35:36 -0500 (EST) Message-ID: <512ADB52.9040008@cn.fujitsu.com> Date: Mon, 25 Feb 2013 11:32:34 +0800 From: Tang Chen MIME-Version: 1.0 Subject: Re: [Bug fix PATCH 1/2] acpi, movablemem_map: Exclude memblock.reserved ranges when parsing SRAT. References: <1361358056-1793-1-git-send-email-tangchen@cn.fujitsu.com> <1361358056-1793-2-git-send-email-tangchen@cn.fujitsu.com> <5124C22B.8030401@cn.fujitsu.com> <5124C32E.1080902@gmail.com> <3908561D78D1C84285E8C5FCA982C28F1E06B55D@ORSMSX108.amr.corp.intel.com> <512ABFF7.9090207@gmail.com> In-Reply-To: <512ABFF7.9090207@gmail.com> Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: owner-linux-mm@kvack.org List-ID: To: Will Huck Cc: "Luck, Tony" , "akpm@linux-foundation.org" , "jiang.liu@huawei.com" , "wujianguo@huawei.com" , "hpa@zytor.com" , "wency@cn.fujitsu.com" , "laijs@cn.fujitsu.com" , "linfeng@cn.fujitsu.com" , "yinghai@kernel.org" , "isimatu.yasuaki@jp.fujitsu.com" , "rob@landley.net" , "kosaki.motohiro@jp.fujitsu.com" , "minchan.kim@gmail.com" , "mgorman@suse.de" , "rientjes@google.com" , "guz.fnst@cn.fujitsu.com" , "rusty@rustcorp.com.au" , "lliubbo@gmail.com" , "jaegeuk.hanse@gmail.com" , "glommer@parallels.com" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" On 02/25/2013 09:35 AM, Will Huck wrote: > On 02/21/2013 06:41 AM, Luck, Tony wrote: >>> What's the relationship between e820 map and SRAT? >> The e820 map (or EFI memory map on some recent systems) provides >> a list of memory ranges together with usage information (e.g. reserved >> for BIOS, or available) and attributes (WB cacheable, uncacheable). >> >> The SRAT table provides topology information for address ranges. It >> tells the OS which memory is close to each cpu, and which is more >> distant. If there are multiple degrees of "distant" then the SLIT table >> provides a matrix of relative latencies between nodes. > > What's the meaning of multiple degrees of "distant" here? Eg, there are > ten nodes, can SRAT tell each node which memory on other node is more > close or distant? If the answer is yes, why need SLIT since processes > can use memory close to their nodes. Hi Will Referring to the ACPI spec, SRAT provides info of each node, and SLIT provides info between nodes and nodes, I think. SRAT provides number of CPUs and memory of node i, memory range, the PXM id which will be mapped to node id, and hotplug info, and so on. SLIT provides a matrix describing the distances between node i and node j. > > > SRAT and SLIT are get from firmware or UEFI? > I think we can get this info from ACPI BIOS. Thanks. :) -- 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