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 582BAC25B07 for ; Wed, 10 Aug 2022 01:09:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id AEC488E0002; Tue, 9 Aug 2022 21:09:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A759C8E0001; Tue, 9 Aug 2022 21:09:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 915E68E0002; Tue, 9 Aug 2022 21:09:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 810AC8E0001 for ; Tue, 9 Aug 2022 21:09:18 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 1BF141C68BD for ; Wed, 10 Aug 2022 01:09:18 +0000 (UTC) X-FDA: 79781899596.10.DBE25BE Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf06.hostedemail.com (Postfix) with ESMTP id 50A63180153 for ; Wed, 10 Aug 2022 01:09:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1660093756; x=1691629756; h=from:to:cc:subject:references:date:in-reply-to: message-id:mime-version; bh=y16BOvHxV1nZ3NiVQoMe+MGNwetNYFK6shxb0qVq6cM=; b=QHbEt5M4PbcXOStRUaHSZwiqKBy6WjOvDgxc8LOLVy1sbp2AlrG5loaS q+qaQBRFB0WUJBo5GqIlQHgfgT/a0uKo1SbvkN2spF/GzruFKKQQNs+fT t1/n4ri4QbT8J7mf0cOR5mQxElt3Y+usTbLauBePJyuiL+h31SiUjGyIF ZnEgo7GmDhCrJpwYgCUzL2momJEwiRSlPdCCsYzsJd2wWy6PUI33/nEYH 3kLyMziRv4C9akjmLeEjL1qaFSKcT/MBetCC0tvRW6PcQMC0yPObnhA+j te+ZzqDrJ9id/QDPiXxGBzOW/TAYSt81EsL0BQLnGjHKebG82fjv1/JEH w==; X-IronPort-AV: E=McAfee;i="6400,9594,10434"; a="277907232" X-IronPort-AV: E=Sophos;i="5.93,225,1654585200"; d="scan'208";a="277907232" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Aug 2022 18:09:14 -0700 X-IronPort-AV: E=Sophos;i="5.93,225,1654585200"; d="scan'208";a="781058671" Received: from yhuang6-desk2.sh.intel.com (HELO yhuang6-desk2.ccr.corp.intel.com) ([10.238.208.55]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Aug 2022 18:09:10 -0700 From: "Huang, Ying" To: Aneesh Kumar K V Cc: linux-mm@kvack.org, akpm@linux-foundation.org, Wei Xu , Yang Shi , Davidlohr Bueso , Tim C Chen , Michal Hocko , Linux Kernel Mailing List , Hesham Almatary , Dave Hansen , Jonathan Cameron , Alistair Popple , Dan Williams , Johannes Weiner , jvgediya.oss@gmail.com Subject: Re: [PATCH v13 4/9] mm/demotion/dax/kmem: Set node's abstract distance to MEMTIER_DEFAULT_DAX_ADISTANCE References: <20220808062601.836025-1-aneesh.kumar@linux.ibm.com> <20220808062601.836025-5-aneesh.kumar@linux.ibm.com> <87o7wuglrq.fsf@yhuang6-desk2.ccr.corp.intel.com> <46c8d7c2-004f-1945-8614-2452d4f28d2a@linux.ibm.com> Date: Wed, 10 Aug 2022 09:09:07 +0800 In-Reply-To: <46c8d7c2-004f-1945-8614-2452d4f28d2a@linux.ibm.com> (Aneesh Kumar K. V.'s message of "Tue, 9 Aug 2022 11:03:22 +0530") Message-ID: <87o7wsgb0s.fsf@yhuang6-desk2.ccr.corp.intel.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=ascii ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1660093757; a=rsa-sha256; cv=none; b=mPLW2psVmZErncGJUbtxEqcGI7+W8mAnkTF8q3w8Nw/lWSmv6IXPkrua3kpdcA1HkeiIxH HQG+QEpJAX4tUJzH224vovQKJ3UX2j+L2+Lhovdefk9+qhImeN/s37wwO+5oyZ1L1J/pK2 Mu8Zbv5ZzQ6H/ghkpRxTGgEX/Q2G2x8= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1660093757; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=4sbn6e9oUmW/B8y76y04P2z9ylHa9/t4OGQ6SGGutVM=; b=F6phepTch2TX/AXg6pYRFXNpq69g8vVlg/tSDGtQtTXYKDfTiljB2WFu8dJHloJxMS1GcG z336hl7sthAXTH3PAvq7uDCM1U7CNFOWbs/Vm2/lM3ra5dU/F+ku+BpxuHDxmWecrlEJyZ DQpDTuFUSWvms+8Z7GNnya6RyQoo0e0= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=QHbEt5M4; spf=pass (imf06.hostedemail.com: domain of ying.huang@intel.com designates 134.134.136.20 as permitted sender) smtp.mailfrom=ying.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com X-Stat-Signature: tgrg9yopy4urmx9g6swb9ii3cppopu56 X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 50A63180153 Authentication-Results: imf06.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=QHbEt5M4; spf=pass (imf06.hostedemail.com: domain of ying.huang@intel.com designates 134.134.136.20 as permitted sender) smtp.mailfrom=ying.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com X-HE-Tag: 1660093756-306228 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: Aneesh Kumar K V writes: > On 8/9/22 8:34 AM, Huang, Ying wrote: >> "Aneesh Kumar K.V" writes: >> >>> By default, all nodes are assigned to the default memory tier which >>> is the memory tier designated for nodes with DRAM >>> >>> Set dax kmem device node's tier to slower memory tier by assigning >>> abstract distance to MEMTIER_DEFAULT_DAX_ADISTANCE. Low-level drivers >>> like papr_scm or ACPI NFIT can initialize memory device type to a >>> more accurate value based on device tree details or HMAT. >> >> I don't know how ACPI NFIT can help here. Can you teach me? >> >> Per my understanding, we may use the information provided by ACPI SLIT >> or HMAT (or device tree via papr_scm) to create memory types. Before >> that is implemented, we just create a memory type with default abstract >> distance. >> > > My idea is to use ACPI NFIT driver that creates a persistent memory region > (nvdimm_region_create) to also create memory type and assign that to the > NUMA node mapping that region. For now NFIT driver manages all the persistent > memory region/DIMM creation (drivers/acpi/nfit/core.c). It can also do the > memory type creation using other ACPI information like SLIT/HMAT etc. Similarly > CXL driver can do the same using CDAT. I still think that it's better to create memory types in dax/kmem.c and CXL driver. But we can discuss further on that later. Best Regards, Huang, Ying