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 545DCC77B73 for ; Sun, 23 Apr 2023 13:48:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229779AbjDWNsK (ORCPT ); Sun, 23 Apr 2023 09:48:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54290 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229441AbjDWNsJ (ORCPT ); Sun, 23 Apr 2023 09:48:09 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 88F94E47; Sun, 23 Apr 2023 06:48:07 -0700 (PDT) Received: from lhrpeml500005.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Q48bg0h4kz67KJs; Sun, 23 Apr 2023 21:43:11 +0800 (CST) Received: from localhost (10.48.150.148) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.23; Sun, 23 Apr 2023 14:48:03 +0100 Date: Sun, 23 Apr 2023 14:48:01 +0100 From: Jonathan Cameron To: Dan Williams CC: Liang Kan , , , , , , , , , , Davidlohr Bueso , Dave Jiang Subject: Re: [PATCH v6 4/5] perf: CXL Performance Monitoring Unit driver Message-ID: <20230423144801.00006efd@Huawei.com> In-Reply-To: <6444603653882_1b41629414@dwillia2-mobl3.amr.corp.intel.com.notmuch> References: <20230413142617.15995-1-Jonathan.Cameron@huawei.com> <20230413142617.15995-5-Jonathan.Cameron@huawei.com> <6444603653882_1b41629414@dwillia2-mobl3.amr.corp.intel.com.notmuch> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.48.150.148] X-ClientProxiedBy: lhrpeml500001.china.huawei.com (7.191.163.213) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 22 Apr 2023 15:31:18 -0700 Dan Williams wrote: > Jonathan Cameron wrote: > > CXL rev 3.0 introduces a standard performance monitoring hardware > > block to CXL. Instances are discovered using CXL Register Locator DVSEC > > entries. Each CXL component may have multiple PMUs. > > > > This initial driver supports a subset of types of counter. > > It supports counters that are either fixed or configurable, but requires > > that they support the ability to freeze and write value whilst frozen. > > > > Development done with QEMU model which will be posted shortly. > > > > Example: > > > > $ perf stat -e cxl_pmu_mem0.0/h2d_req_snpcur/ -e cpmu0/h2d_req_snpdata/ -e cpmu0/clock_ticks/ sleep 1 > > > > Performance counter stats for 'system wide': > > > > 96,757,023,244,321 cxl_pmu_mem0.0/h2d_req_snpcur/ > > 96,757,023,244,365 cxl_pmu_mem0.0/h2d_req_snpdata/ > > 193,514,046,488,653 cxl_pmu_mem0.0/clock_ticks/ > > > > 1.090539600 seconds time elapsed > > > > Reviewed-by: Dave Jiang > > Reviewed-by: Kan Liang > > Signed-off-by: Jonathan Cameron > > Jonathan, I was awaiting a "perf maintainer ack" before applying this, > only to now realize there is no maintainer entry for drivers/perf/ in > general, only "ARM PMU PROFILING AND DEBUGGING". Were you waiting on any > additional acks from perf folks for this? I'm always hopeful. For everything similar we've done in the past in drivers/perf, Will Deacon has taken a look and ultimately taken the series (often Mark has as well), but then those drivers could be very loosely termed ARM PMU on basis they happen to be PMUs on an ARM architecture system even if they have nothing at all to do with the ARM architecture itself (e.g. our PCI PMUs). I see the riscv stuff has been going in drivers/perf without an Ack from them though so there is precedent for non ARM stuff in this directory going in through other trees despite the catch all maintainers entry. So, Will / Mark do you consider this in your maintainer scope? Your input is welcome either way but as you might be very busy I don't want to commit you to taking a look at this CXL driver. > > If there are no objections I think this can be included in the back half > of the merge window for v6.4, as it stands now I was still awaiting the > final go ahead. That would be great if possible. If not I'll just back new features up behind this series and hopefully a larger set might go in next cycle. Thanks, Jonathan