Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932272Ab3GKLAA (ORCPT ); Thu, 11 Jul 2013 07:00:00 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:43221 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932081Ab3GKK76 (ORCPT ); Thu, 11 Jul 2013 06:59:58 -0400 Date: Thu, 11 Jul 2013 11:58:43 +0100 From: Will Deacon To: Vince Weaver Cc: Peter Zijlstra , Michael Ellerman , Vince Weaver , Runzhen Wang , "linuxppc-dev@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" , "paulus@samba.org" , "acme@redhat.com" , "mingo@kernel.org" , Stephane Eranian , "sukadev@linux.vnet.ibm.com" , "xiaoguangrong@linux.vnet.ibm.com" Subject: Re: [PATCH v2 2/2] perf tools: Make Power7 events available for perf Message-ID: <20130711105843.GG32197@mudshark.cambridge.arm.com> References: <1372170933-4538-1-git-send-email-runzhen@linux.vnet.ibm.com> <1372170933-4538-3-git-send-email-runzhen@linux.vnet.ibm.com> <20130704125218.GA21134@concordia> <20130704125700.GM18898@dyad.programming.kicks-ass.net> <20130709012952.GA7185@concordia> <20130709081434.GI25631@dyad.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1870 Lines: 42 On Tue, Jul 09, 2013 at 04:05:30PM +0100, Vince Weaver wrote: > On Tue, 9 Jul 2013, Peter Zijlstra wrote: > > > On Mon, Jul 08, 2013 at 10:24:34PM -0400, Vince Weaver wrote: > > > > > > So something like they have on ARM? > > > > > > vince@pandaboard:/sys/bus/event_source/devices$ ls -l > > > lrwxrwxrwx 1 root root 0 Jul 8 21:57 ARMv7 Cortex-A9 -> ../../../devices/ARMv7 Cortex-A9 > > > lrwxrwxrwx 1 root root 0 Jul 8 21:57 breakpoint -> ../../../devices/breakpoint > > > lrwxrwxrwx 1 root root 0 Jul 8 21:57 software -> ../../../devices/software > > > lrwxrwxrwx 1 root root 0 Jul 8 21:57 tracepoint -> ../../../devices/tracepoint > > > > Right so what I remember of the ARM case is that their /proc/cpuinfo isn't > > sufficient to identify their PMU. And they don't have a cpuid like instruction > > at all. > > libpfm4 uses the > CPU part : 0xc09 > line in /proc/cpuinfo on ARM, and that's enough for the processors PAPI > supports (Cortex A8/A9/A15 plus the 1176 on the raspberry-pi). I'm > guessing it wouldn't be enough if we wanted to support *all* ARMs with > PMUs. The CPU part you cite is actually A9-specific, so you probably want to probe each CPU specifically. Take a look at the cpuinfo parsing in OProfile (used by operf). > And speaking of ARM, I should be railing at them for breaking the ABI too, > with their (understandable yet still ABI breaking) decision to remove > BogoMIPS from /proc/cpuinfo. That change will impact PAPI as well as > various other programs I maintain that have the misfortune of parsing that > file. Really? Why are you checking for that line at all? Will -- 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/