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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 B5908C2B9F4 for ; Fri, 25 Jun 2021 16:18:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9538861976 for ; Fri, 25 Jun 2021 16:18:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229940AbhFYQUw (ORCPT ); Fri, 25 Jun 2021 12:20:52 -0400 Received: from mga05.intel.com ([192.55.52.43]:3083 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229445AbhFYQUv (ORCPT ); Fri, 25 Jun 2021 12:20:51 -0400 IronPort-SDR: LJ3/kmBeNYtBxvNPJxipEv/uejtkR0GbmpWu4MQnUE4aeGnLt8Sd9246dLXi5+OwQ7NQL4j9lk T/hVDSF3LA3A== X-IronPort-AV: E=McAfee;i="6200,9189,10026"; a="293334646" X-IronPort-AV: E=Sophos;i="5.83,299,1616482800"; d="scan'208";a="293334646" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Jun 2021 09:18:30 -0700 IronPort-SDR: RY9/tckYGDaQjbLmr+ko/K0n7McmAgYGkcNaqEQWqmyRiGuzx12JMhajkMA8K4ESy1KkFn6yrQ 80c54OQ+D2Jw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.83,299,1616482800"; d="scan'208";a="557742457" Received: from linux.intel.com ([10.54.29.200]) by fmsmga001.fm.intel.com with ESMTP; 25 Jun 2021 09:18:30 -0700 Received: from [10.212.190.24] (kliang2-MOBL.ccr.corp.intel.com [10.212.190.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by linux.intel.com (Postfix) with ESMTPS id 7813B58060A; Fri, 25 Jun 2021 09:18:29 -0700 (PDT) Subject: Re: [PATCH 2/7] perf: Create a symlink for a PMU From: "Liang, Kan" To: Andi Kleen , Greg KH Cc: peterz@infradead.org, mingo@redhat.com, linux-kernel@vger.kernel.org, eranian@google.com, namhyung@kernel.org, acme@kernel.org, jolsa@redhat.com References: <1624497729-158864-1-git-send-email-kan.liang@linux.intel.com> <1624497729-158864-3-git-send-email-kan.liang@linux.intel.com> <1e536604-cf93-0f09-401e-2073924c5582@linux.intel.com> <29d5f315-578f-103c-9523-ae890e29c7e7@linux.intel.com> <540d8a38-da12-56c8-8306-8d3d61ae1d6b@linux.intel.com> <6f2941a4-4a32-ea09-bbc6-5a8e4836411b@linux.intel.com> <82fe02c8-2ac6-fc53-490c-382df3e07dc4@linux.intel.com> Message-ID: <1edc6666-c4b3-ebf5-964a-e5ffc97d8563@linux.intel.com> Date: Fri, 25 Jun 2021 12:18:28 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <82fe02c8-2ac6-fc53-490c-382df3e07dc4@linux.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/25/2021 11:57 AM, Liang, Kan wrote: > > > On 6/25/2021 11:44 AM, Andi Kleen wrote: >> >>> We have an attribute "caps/pmu_name" for the core PMU. Maybe we >>> should add it for uncore PMU as well. For example, >>> >>> $ cat /sys/devices/uncore_type_0_0/caps/pmu_name >>> cha_0 >>> >>> Userspace tool can get clues about what type_0_0 is. >> >> It would break all the old tools, but I suppose it could work for >> updated tools. >> > > Right, users have to update their perf tool to use the new name, > uncore_cha_0. I think the above example is misleading. Let me rephrase. Here is what I'm planing to do in V2. With the V2 platform-specific patch, uncore driver will only create a meaningful uncore name, e.g., uncore_cha_0. An attribute "caps/pmu_name" is also created to indicate the previous name. For example, $ cat /sys/devices/uncore_cha_0/caps/pmu_name type_0_0 If any users use the old numeric name, they have to update either their script or a perf tool which supports "caps/pmu_name". In the future, if the users already use a perf tool which supports "caps/pmu_name", nothing needs to be updated. The old numeric name should just work. Thanks, Kan