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 03694ECAAA1 for ; Fri, 2 Sep 2022 06:12:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235444AbiIBGMO (ORCPT ); Fri, 2 Sep 2022 02:12:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52900 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235413AbiIBGML (ORCPT ); Fri, 2 Sep 2022 02:12:11 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1E2BB9F93 for ; Thu, 1 Sep 2022 23:12:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1662099130; x=1693635130; h=from:to:cc:subject:references:date:in-reply-to: message-id:mime-version; bh=V1LrsReCOZOn0uyOPVtRtxNfCUOuD4F2LfutTySDfRs=; b=EJOeJqIJLj8PExMTwWibw9O/Kxu3U2Qvnl6Do19+0jaqi0Qs3o0eUnqJ euPM3TF6MqiiSAp8pvyS3PzIM8GvX04Ut7dsxVvX22ZZoNF/S+nYS2ggX fvC0u56sJ4V94DOZEMWy+RIvM+u45TWGwnF/XOSIqC9Bf3fnVkaJVFqDG DbjYoWsMbIupkuQkkN6Xi1ZT3d1syMPCXa3LB/Ihn/KjXbB0drlvDXA+5 F6WgNQWLJ8RO0TUG7Qp3l27vitKl0lsANeOancCh+KJU+D33kUPxsn6sc lDRI0sL7GJdx9SaSfSonJgicpDiYWQ9DM+hoB9cy1EXi12A1dGwKUlK4j A==; X-IronPort-AV: E=McAfee;i="6500,9779,10457"; a="296686273" X-IronPort-AV: E=Sophos;i="5.93,283,1654585200"; d="scan'208";a="296686273" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Sep 2022 23:12:09 -0700 X-IronPort-AV: E=Sophos;i="5.93,283,1654585200"; d="scan'208";a="563850475" Received: from yhuang6-desk2.sh.intel.com (HELO yhuang6-desk2.ccr.corp.intel.com) ([10.238.208.55]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Sep 2022 23:12:04 -0700 From: "Huang, Ying" To: Aneesh Kumar K V Cc: Wei Xu , Johannes Weiner , Linux MM , Andrew Morton , Yang Shi , Davidlohr Bueso , Tim C Chen , Michal Hocko , Linux Kernel Mailing List , Hesham Almatary , Dave Hansen , Jonathan Cameron , Alistair Popple , Dan Williams , jvgediya.oss@gmail.com, Bharata B Rao , Greg Thelen Subject: Re: [PATCH v3 updated] mm/demotion: Expose memory tier details via sysfs References: <20220830081736.119281-1-aneesh.kumar@linux.ibm.com> <87tu5rzigc.fsf@yhuang6-desk2.ccr.corp.intel.com> <87pmgezkhp.fsf@yhuang6-desk2.ccr.corp.intel.com> <87fshaz63h.fsf@yhuang6-desk2.ccr.corp.intel.com> <698120ce-d4df-3d13-dea9-a8f5c298783c@linux.ibm.com> Date: Fri, 02 Sep 2022 14:12:02 +0800 In-Reply-To: <698120ce-d4df-3d13-dea9-a8f5c298783c@linux.ibm.com> (Aneesh Kumar K. V.'s message of "Fri, 2 Sep 2022 11:16:14 +0530") Message-ID: <87bkryz4nh.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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Aneesh Kumar K V writes: > On 9/2/22 11:10 AM, Huang, Ying wrote: >> Aneesh Kumar K V writes: >> >>> On 9/2/22 10:39 AM, Wei Xu wrote: >>>> On Thu, Sep 1, 2022 at 5:33 PM Huang, Ying wrote: >>>>> >>>>> Aneesh Kumar K V writes: >>>>> >>>>>> On 9/1/22 12:31 PM, Huang, Ying wrote: >>>>>>> "Aneesh Kumar K.V" writes: >>>>>>> >>>>>>>> This patch adds /sys/devices/virtual/memory_tiering/ where all memory tier >>>>>>>> related details can be found. All allocated memory tiers will be listed >>>>>>>> there as /sys/devices/virtual/memory_tiering/memory_tierN/ >>>>>>>> >>>>>>>> The nodes which are part of a specific memory tier can be listed via >>>>>>>> /sys/devices/virtual/memory_tiering/memory_tierN/nodes >>>>>>> >>>>>>> I think "memory_tier" is a better subsystem/bus name than >>>>>>> memory_tiering. Because we have a set of memory_tierN devices inside. >>>>>>> "memory_tier" sounds more natural. I know this is subjective, just my >>>>>>> preference. >>>>>>> >>> >>> >>> I missed replying to this earlier. I will keep memory_tiering as subsystem name in v4 >>> because we would want it to a susbsystem where all memory tiering related details can be found >>> including memory type in the future. This is as per discussion >>> >>> https://lore.kernel.org/linux-mm/CAAPL-u9TKbHGztAF=r-io3gkX7gorUunS2UfstudCWuihrA=0g@mail.gmail.com >> >> I don't think that it's a good idea to mix 2 types of devices in one >> subsystem (bus). If my understanding were correct, that breaks the >> driver core convention. >> > > All these are virtual devices .I am not sure i follow what you mean by 2 types of devices. > memory_tiering is a subsystem that represents all the details w.r.t memory tiering. It shows > details of memory tiers and can possibly contain details of different memory types . IMHO, memory_tier and memory_type are 2 kind of devices. They have almost totally different attributes (sysfs file). So, we should create 2 buses for them. Each has its own attribute group. "virtual" itself isn't a subsystem. Best Regards, Huang, Ying