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 A7FE6C04FE0 for ; Wed, 16 Aug 2023 08:01:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242662AbjHPIA5 (ORCPT ); Wed, 16 Aug 2023 04:00:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242630AbjHPIAn (ORCPT ); Wed, 16 Aug 2023 04:00:43 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D2737109 for ; Wed, 16 Aug 2023 01:00:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1692172842; x=1723708842; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=Ai5IukHLeM/f44frIXUhn+qH7D7SKtBu6usOlz70v1E=; b=kGHZEz3UaHB3vkH8I0fdaqO5NwmvCNyKMT98NwWZrhWddq96CLL6Tgzq mIB18965xNF/jCuCW73aYW5TUs/p/0TRucOLbglPYf/jJOX4zJNaGikcu nEDTH1GbmGFtSBDD96q1rn6ReNVzZHlwmkYTohwsu9m0obItrrlA3zC25 x4TcdWBlt0efc3AsyZlzkz2AuFsk4HXpP2AIEn4nlfhLsc1FSyOJ1BzqI SfmgvEy0hxRHJqN3tNmR3sZ+GRMfuHZD9kDeIwwZ9+xtznPZ8pyWZ5uKI ilkASRm1sb3rBaTCteeqAp3yJhBiCq465HDvy8pJd2W5sv7l3IUSzQiBg w==; X-IronPort-AV: E=McAfee;i="6600,9927,10803"; a="371377637" X-IronPort-AV: E=Sophos;i="6.01,176,1684825200"; d="scan'208";a="371377637" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Aug 2023 01:00:42 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10803"; a="804112767" X-IronPort-AV: E=Sophos;i="6.01,176,1684825200"; d="scan'208";a="804112767" Received: from yhuang6-mobl2.sh.intel.com ([10.238.6.30]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Aug 2023 01:00:38 -0700 From: Huang Ying To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , "Aneesh Kumar K . V" , Wei Xu , Alistair Popple , Dan Williams , Dave Hansen , Davidlohr Bueso , Johannes Weiner , Jonathan Cameron , Michal Hocko , Yang Shi , Rafael J Wysocki Subject: [PATCH -V2 0/4] memory tiering: calculate abstract distance based on ACPI HMAT Date: Wed, 16 Aug 2023 16:00:20 +0800 Message-Id: <20230816080024.105554-1-ying.huang@intel.com> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We have the explicit memory tiers framework to manage systems with multiple types of memory, e.g., DRAM in DIMM slots and CXL memory devices. Where, same kind of memory devices will be grouped into memory types, then put into memory tiers. To describe the performance of a memory type, abstract distance is defined. Which is in direct proportion to the memory latency and inversely proportional to the memory bandwidth. To keep the code as simple as possible, fixed abstract distance is used in dax/kmem to describe slow memory such as Optane DCPMM. To support more memory types, in this series, we added the abstract distance calculation algorithm management mechanism, provided a algorithm implementation based on ACPI HMAT, and used the general abstract distance calculation interface in dax/kmem driver. So, dax/kmem can support HBM (high bandwidth memory) in addition to the original Optane DCPMM. Changelog: V2: - Fix a typo in 4/4. - Collected reviewed-by and tested-by. V1 (from RFC): - Added some comments per Aneesh's comments, Thanks! Best Regards, Huang, Ying