From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754434AbcGTOiu (ORCPT ); Wed, 20 Jul 2016 10:38:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37152 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753981AbcGTOiq (ORCPT ); Wed, 20 Jul 2016 10:38:46 -0400 Date: Wed, 20 Jul 2016 16:38:42 +0200 From: Jiri Olsa To: Nikolay Borisov Cc: Peter Zijlstra , "Linux-Kernel@Vger. Kernel. Org" , andi@firstfloor.org Subject: Re: Strange behavior of perf top with PEBS Message-ID: <20160720143842.GB25992@krava> References: <578F7C82.6090500@kyup.com> <20160720143417.GA25992@krava> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160720143417.GA25992@krava> User-Agent: Mutt/1.6.2 (2016-07-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 20 Jul 2016 14:38:45 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 20, 2016 at 04:34:17PM +0200, Jiri Olsa wrote: > On Wed, Jul 20, 2016 at 04:28:34PM +0300, Nikolay Borisov wrote: > > Hello, > > > > Running perf version 4.4.14.g0cb188d (no modification to the PMU/perf > > code) I observed that "perf top" counts no cycles and produces no > > output. After a bit of head scratching and testing I figured that > > running "perf top -e cycles" actually works whereas the default option > > is equivalent to running "perf top -e cycles:p". So the latter version > > seems to not work on my machine. > > hum, I think Core2 has PEBs valid only for instructions not cycles.. > > I'll check why perf top forcing the precise for cycles > I thought we had that automated already oops, too soon ;) we have: perf/x86/intel: Fix Core2,Atom,NHM,WSM cycles:pp events commit 517e6341fa123ec3a2f9ea78ad547be910529881 Author: Peter Zijlstra Date: Sat Apr 11 12:16:22 2015 +0200 so i guess it should work.. checking ;-) jirka