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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_HIGH,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 47EA8C28CF6 for ; Fri, 3 Aug 2018 13:33:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E767721763 for ; Fri, 3 Aug 2018 13:33:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="IV0Iev/Z" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E767721763 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732037AbeHCP3Z (ORCPT ); Fri, 3 Aug 2018 11:29:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:42714 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728758AbeHCP3Z (ORCPT ); Fri, 3 Aug 2018 11:29:25 -0400 Received: from jouet.infradead.org (unknown [186.208.79.165]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F23512175D; Fri, 3 Aug 2018 13:33:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1533303182; bh=Y22UxhHswyuxWH2fD+DUOM2O/RHz7KWbRJjXabSSSrE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IV0Iev/ZFSWmNvGoyYyt3t0s6ED5JTwT5m1wcCF4GUtiBDjlxiWt3fne4jqqyD2Zf U3Ja95k/qFzXbM2sAGqc++BH5dT4X3AZCClnJiZ9o0TWWfHZAzgrq27CxSoD0Rdple RWJiDOF/PZzHqeR8KM2MZH9Jf8ET7vFrxJoY1b5g= Received: by jouet.infradead.org (Postfix, from userid 1000) id 52B5C140A1C; Fri, 3 Aug 2018 10:32:52 -0300 (-03) Date: Fri, 3 Aug 2018 10:32:52 -0300 From: Arnaldo Carvalho de Melo To: Hendrik Brueckner Cc: Thomas Richter , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, brueckner@linux.vnet.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com Subject: Re: [PATCH 1/3] perf auxtrace: Support for perf report -D for s390 Message-ID: <20180803133252.GE7996@kernel.org> References: <20180802074622.13641-1-tmricht@linux.ibm.com> <20180802074622.13641-2-tmricht@linux.ibm.com> <20180802124909.GB7996@kernel.org> <20180803100758.GA28475@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180803100758.GA28475@linux.ibm.com> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Fri, Aug 03, 2018 at 12:07:58PM +0200, Hendrik Brueckner escreveu: > Arnaldo, > > On Thu, Aug 02, 2018 at 09:49:09AM -0300, Arnaldo Carvalho de Melo wrote: > > Em Thu, Aug 02, 2018 at 09:46:20AM +0200, Thomas Richter escreveu: > > > Add initial support for s390 auxiliary traces using the > > > CPU-Measurement Sampling Facility. > > > > Could you please provide one or two paragraphs explaining what is this > > "CPU-Measurement Sampling Facility", in which hardware this is available > > (all s/390 hardware has it? Just the 64-bit model(s)?) and provide a > > public URL for people interested in further reading? > > The CPU-Measurement Facility (CPU-MF) provides a set of functions to obtain > performance information on the mainframe. Basically, it was introduced > with System z10 years ago for the z/Architecture, that means, 64-bit. > For Linux, there are two facilities of interest, counter facility and sampling > facility. The counter facility provides hardware counters for instructions, > cycles, crypto-activities, and many more. > > The sampling facility is a hardware sampler that when started will write > samples at a particular interval into a sampling buffer. At some point, > for example, if a sample block is full, it generates an interrupt to collect > samples (while the sampler continues to run). > > Few years ago, I started to provide the a perf PMU to use the counter > and sampling facilities. Recently, the device driver was updated to also > "export" the sampling buffer into the AUX area. Thomas now completed the > related perf work to interpret and process these AUX data. > > If people are more interested in the sampling facility, they can have a > look into: > > - The Load-Program-Parameter and the CPU-Measurement Facilities, SA23-2260-05 > http://www-01.ibm.com/support/docview.wss?uid=isg26fcd1cc32246f4c8852574ce0044734a > > and to learn how-to use it for Linux on Z, have look at chapter 54, > "Using the CPU-measurement facilities" in the: > > - Device Drivers, Features, and Commands, SC33-8411-34 > http://public.dhe.ibm.com/software/dw/linux390/docu/l416dd34.pdf ----------------------- Thanks a lot, I added this to the first commit, people investigating this should be able to find that when doing research about the implementation details. - Arnaldo