From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753676Ab0EERXq (ORCPT ); Wed, 5 May 2010 13:23:46 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:44122 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753137Ab0EERXo (ORCPT ); Wed, 5 May 2010 13:23:44 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:content-transfer-encoding :in-reply-to:user-agent; b=DKSFqZqCih/3sLuFrlxexUN0387MHweHgeQGxWeiGm1bnLcrQaQX1M/B1gETWSAlqz dyab/yULwxHEZDe9/8xoWTopXLCq32W1OENYD5NlUQME2OQ8YLw+D1RfFKtF7iiYZfBu jlFYjvdzBMLMAHdg78sCd+hhDhVcvV9CItIUQ= Date: Wed, 5 May 2010 19:23:42 +0200 From: Frederic Weisbecker To: Ronny =?iso-8859-1?Q?Tsch=FCter?= Cc: rostedt@goodmis.org, Arjan van de Ven , Ingo Molnar , Thomas Gleixner , Linux Kernel Mailing List Subject: Re: Tracing of power:power_start events doesn't work Message-ID: <20100505172339.GC6320@nowhere> References: <4BDECD66.2010906@tu-dresden.de> <1273019517.22438.10.camel@gandalf.stny.rr.com> <4BE11169.3010602@tu-dresden.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <4BE11169.3010602@tu-dresden.de> 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 On Wed, May 05, 2010 at 08:34:17AM +0200, Ronny Tschüter wrote: > On Wed 2010-05-05 02:31, Steven Rostedt wrote: >> On Mon, 2010-05-03 at 15:19 +0200, Ronny Tschüter wrote: >> >>> Hello, >>> >>> i use kernel version 2.6.33.2 (x86-64, Core 2 Duo) and the perf events >>> to track frequency and c states of my cpu. But if i want to trace >>> power:power_start events, it does not work. After typing >>> >>> echo "power:power_start" | sudo tee set_event >>> >>> on the console, the trace doesn't contain such events. >>> power:power_frequency and power:power_end events are reported correctly >>> by the system. I read in the mailing list that Robert Schoene had a >>> similiar problem, but with power:power_end events. Is there a known bug >>> regarding to trace_power_start methods in process.c? >>> >> Is this for perf or ftrace? I'm assuming you did this from the debugfs >> tracing directory. The set_event file is for ftrace not perf. >> > It is for perf - i'm interested in event tracing. I used the event > tracing system like it is described in Documentation/trace/events.txt. > In addition i wrote a program which uses syscall(__NR_perf_counter_open, > ... ) to trace power events. But the result is the same - > power:power_end events are reported, power:power_start events not. > > Bye Ronny Hi, can you please compare the perf and ftrace output to see if ftrace works while perf doesn't for example? In perf: perf record -f -c 1 -a -e power:power_start ^C perf report In ftrace: echo 1 > $DEBUGFS/tracing/events/power/power_start/enable cat $DEBUGFS/trace_pipe Thanks.