From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758763AbcHDPaL (ORCPT ); Thu, 4 Aug 2016 11:30:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51494 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758687AbcHDPaF (ORCPT ); Thu, 4 Aug 2016 11:30:05 -0400 Date: Thu, 4 Aug 2016 17:29:26 +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: <20160804152926.GA25592@krava> References: <578F7C82.6090500@kyup.com> <20160720143417.GA25992@krava> <20160720143842.GB25992@krava> <579749E6.1030408@kyup.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <579749E6.1030408@kyup.com> 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]); Thu, 04 Aug 2016 15:29:29 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 26, 2016 at 02:30:46PM +0300, Nikolay Borisov wrote: > > > On 07/20/2016 05:38 PM, Jiri Olsa wrote: > > 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 ;-) > > Any update on that? sorry for late response.. I checked on f22 kernel and it's missing the core2 PEBs fix: 1424a09a9e18 perf/x86: fix PEBS issues on Intel Atom/Core2 which was introduced in 4.5.. you should upgrade or include this patch jirka