Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752239AbZFWJKJ (ORCPT ); Tue, 23 Jun 2009 05:10:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752531AbZFWJJ6 (ORCPT ); Tue, 23 Jun 2009 05:09:58 -0400 Received: from mga06.intel.com ([134.134.136.21]:28585 "EHLO orsmga101.jf.intel.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752161AbZFWJJ5 (ORCPT ); Tue, 23 Jun 2009 05:09:57 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.42,274,1243839600"; d="scan'208";a="424523290" Date: Tue, 23 Jun 2009 16:53:21 +0800 From: Yong Wang To: eranian@gmail.com Cc: Yong Wang , "Wang, Yong Y" , Ingo Molnar , Peter Zijlstra , LKML , Paul Mackerras , Andi Kleen Subject: Re: perf_counter Atom patch Message-ID: <20090623085321.GC23534@ywang-moblin2.bj.intel.com> References: <7c86c4470906221326j6edbf9f3g5d65e96d86aaf7ab@mail.gmail.com> <9F0C1DB20AFA954FA1DA05309350433D7B2584D1@pdsmsx503.ccr.corp.intel.com> <7c86c4470906230045k578bc146wa0e09e4094d937a5@mail.gmail.com> <20090623075959.GA23534@ywang-moblin2.bj.intel.com> <7c86c4470906230127g4f574b61p24f109c7a94c6e39@mail.gmail.com> <7c86c4470906230140p35ce043fw24e0c20651568f31@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7c86c4470906230140p35ce043fw24e0c20651568f31@mail.gmail.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1670 Lines: 44 On Tue, Jun 23, 2009 at 10:40:45AM +0200, stephane eranian wrote: > Yong, > > On Tue, Jun 23, 2009 at 10:27 AM, stephane > eranian wrote: > > Hi, > > > > On Tue, Jun 23, 2009 at 9:59 AM, Yong Wang wrote: > >> On Tue, Jun 23, 2009 at 09:45:03AM +0200, stephane eranian wrote: > >>> > >>> Unfortunately, I don't have a N270 to compare with your results. > >>> We need to verify whether or not N270 implements the fixed counters. > >>> Does it report architected perfmon v3 or v1? > >>> > >> > >> All Atom processors report perfmon v3 as specified in SDM. N270 is no > >> exception. > >> > > V3 does not set a minimal number of fixed counters, could be zero. But > > that seems > > odd. Let me ask around. > > > Second thought on this: > x86_pmu.num_counters_fixed = > max((int)edx.split.num_counters_fixed, 3); > > rdmsrl(MSR_CORE_PERF_GLOBAL_CTRL, x86_pmu.intel_ctrl); > > > Forcing num_counter_fixed is not enough, you need to make sure they are actually > activated in GLOBAL_CTRL, i.e., make sure bits 32-34 are set in intel_ctrl. > Depending on which machine you're on, the power on value for GLOBAL_CTRL > changes. The correct value for it should be that ONLY generic counters are on > by default. > Oh, this might be why fixed counter do not work on my Atom box. I will look into it. BTW, why should ONLY generic counters be on by default? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/