From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753626AbbLFNLK (ORCPT ); Sun, 6 Dec 2015 08:11:10 -0500 Received: from mail-wm0-f45.google.com ([74.125.82.45]:37510 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752403AbbLFNLH (ORCPT ); Sun, 6 Dec 2015 08:11:07 -0500 Date: Sun, 6 Dec 2015 14:11:02 +0100 From: Ingo Molnar To: vincent.weaver@maine.edu, jolsa@redhat.com, torvalds@linux-foundation.org, eranian@google.com, tglx@linutronix.de, acme@redhat.com, ak@linux.intel.com, peterz@infradead.org, linux-kernel@vger.kernel.org, hpa@zytor.com Cc: linux-tip-commits@vger.kernel.org Subject: Re: [tip:perf/core] perf/x86: Use INST_RETIRED.PREC_DIST for cycles: ppp Message-ID: <20151206131102.GA12167@gmail.com> References: <1448929689-13771-2-git-send-email-andi@firstfloor.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * tip-bot for Andi Kleen wrote: > Commit-ID: 4576ceaa56a86bd0c041c204d51c3f3ca582a49c > Gitweb: http://git.kernel.org/tip/4576ceaa56a86bd0c041c204d51c3f3ca582a49c > Author: Andi Kleen > AuthorDate: Mon, 30 Nov 2015 16:28:09 -0800 > Committer: Ingo Molnar > CommitDate: Fri, 4 Dec 2015 10:08:04 +0100 > > perf/x86: Use INST_RETIRED.PREC_DIST for cycles:ppp > > Add a new 'three-p' precise level, that uses INST_RETIRED.PREC_DIST as > base. The basic mechanism of abusing the inverse cmask to get all > cycles works the same as before. So this commit regressed on the follwing Intel Nehalem box: processor : 15 vendor_id : GenuineIntel cpu family : 6 model : 26 model name : Intel(R) Xeon(R) CPU X55600 @ 2.80GHz stepping : 5 cpu MHz : 2793.000 cache size : 8192 KB it has this perf bootup signature: 0.272504] Performance Events: PEBS fmt1+, 16-deep LBR, Nehalem events, Intel PMU driver. 0.281356] perf_event_intel: CPU erratum AAJ80 worked around the symptom is that latest 'perf top' and 'perf record' produces no samples. So I've removed this commit and the related Skylake commit from -tip: 4576ceaa56a8 perf/x86: Use INST_RETIRED.PREC_DIST for cycles:ppp ac1e1d30cf90 perf/x86: Use INST_RETIRED.TOTAL_CYCLES_PS for cycles:pp for Skylake you need to do better testing next time around. Note: if you resubmit the patches, please also pick up the updates commit changelogs from the tip-bot emails, don't use your original changelogs. Also, I'm not convinced we need a new 'ppp' qualifier for any of this, why not just replace 'pp' with this event - 'pp' is meant to be our most precise event. Thanks, Ingo