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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EB834C1B0F7 for ; Fri, 18 Jan 2019 20:44:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B839F20883 for ; Fri, 18 Jan 2019 20:44:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729551AbfARUoD (ORCPT ); Fri, 18 Jan 2019 15:44:03 -0500 Received: from mga14.intel.com ([192.55.52.115]:41566 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729471AbfARUoC (ORCPT ); Fri, 18 Jan 2019 15:44:02 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 18 Jan 2019 12:44:02 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,492,1539673200"; d="scan'208";a="128950048" Received: from unknown (HELO localhost.localdomain) ([10.232.112.69]) by orsmga001.jf.intel.com with ESMTP; 18 Jan 2019 12:44:01 -0800 Date: Fri, 18 Jan 2019 13:42:51 -0700 From: Keith Busch To: "Rafael J. Wysocki" Cc: Linux Kernel Mailing List , ACPI Devel Maling List , Linux Memory Management List , Greg Kroah-Hartman , Dave Hansen , Dan Williams Subject: Re: [PATCHv4 05/13] Documentation/ABI: Add new node sysfs attributes Message-ID: <20190118204251.GI31543@localhost.localdomain> References: <20190116175804.30196-1-keith.busch@intel.com> <20190116175804.30196-6-keith.busch@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 17, 2019 at 12:41:19PM +0100, Rafael J. Wysocki wrote: > On Wed, Jan 16, 2019 at 6:59 PM Keith Busch wrote: > > > > Add entries for memory initiator and target node class attributes. > > > > Signed-off-by: Keith Busch > > I would recommend combining this with the previous patch, as the way > it is now I need to look at two patches at the time. :-) Will do. > > --- > > Documentation/ABI/stable/sysfs-devices-node | 25 ++++++++++++++++++++++++- > > 1 file changed, 24 insertions(+), 1 deletion(-) > > > > diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node > > index 3e90e1f3bf0a..a9c47b4b0eee 100644 > > --- a/Documentation/ABI/stable/sysfs-devices-node > > +++ b/Documentation/ABI/stable/sysfs-devices-node > > @@ -90,4 +90,27 @@ Date: December 2009 > > Contact: Lee Schermerhorn > > Description: > > The node's huge page size control/query attributes. > > - See Documentation/admin-guide/mm/hugetlbpage.rst > > \ No newline at end of file > > + See Documentation/admin-guide/mm/hugetlbpage.rst > > + > > +What: /sys/devices/system/node/nodeX/classY/ > > +Date: December 2018 > > +Contact: Keith Busch > > +Description: > > + The node's relationship to other nodes for access class "Y". > > + > > +What: /sys/devices/system/node/nodeX/classY/initiator_nodelist > > +Date: December 2018 > > +Contact: Keith Busch > > +Description: > > + The node list of memory initiators that have class "Y" access > > + to this node's memory. CPUs and other memory initiators in > > + nodes not in the list accessing this node's memory may have > > + different performance. > > This does not follow the general "one value per file" rule of sysfs (I > know that there are other sysfs files with more than one value in > them, but it is better to follow this rule as long as that makes > sense). I think it actually does make sense to use "%*pbl" format here. The type we're displaying is a bit array, so this is one value for that attribute. There are many precedents for disapling bit arrays this way. The existing node attributes that we're appending to show cpu lists, and the top loevel shows node lists for "possible", "online", "has_memory", "has_cpu". This new attribute should fit well with exisiting similar attributes from this subsystem. > > + > > +What: /sys/devices/system/node/nodeX/classY/target_nodelist > > +Date: December 2018 > > +Contact: Keith Busch > > +Description: > > + The node list of memory targets that this initiator node has > > + class "Y" access. Memory accesses from this node to nodes not > > + in this list may have differet performance. > > -- > > Same here. > > And if you follow the recommendation given in the previous message > (add "initiators" and "targets" subdirs under "classX"), you won't > even need the two files above. I think that makes sense, I'll take try out this suggestion. > And, of course, the symlinks part needs to be documented as well. I > guess you can follow the > Documentation/ABI/testing/sysfs-devices-power_resources_D0 with that.