From mboxrd@z Thu Jan 1 00:00:00 1970 From: GeunSik Lim Subject: Re: [PATCH] Update old Mini-HOWTO for ftrace Date: Tue, 7 Apr 2009 14:08:10 +0900 Message-ID: <49b7c2350904062208qc16ef6ag9a33bef66721f4e@mail.gmail.com> References: <49b7c2350904060702j3f725a45ub5e7d3ee3af883c1@mail.gmail.com> <1239068812.4753.15.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ingo Molnar , rt-users , "linux-kernel@vger.kernel.org" , Nikanth Karthikensan To: Steven Rostedt Return-path: Received: from rv-out-0506.google.com ([209.85.198.233]:52831 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750979AbZDGFIM convert rfc822-to-8bit (ORCPT ); Tue, 7 Apr 2009 01:08:12 -0400 In-Reply-To: <1239068812.4753.15.camel@localhost.localdomain> Sender: linux-rt-users-owner@vger.kernel.org List-ID: Dear steven, I confirm http://lkml.org/lkml/2009/3/23/24 webpage now. I am gratified with a similar patch that another people sent this prob= lem. In fact, I figured out trivial problem of old mini-HOWTO according to http://www.redhat.com/docs/en-US/Red_Hat_Enterprise_MRG/1.1/html/Realti= me_Tuning_Guide/sect-Realtime_Tuning_Guide-Realtime_Specific_Tuning-Usi= ng_the_ftrace_Utility_for_Tracing_Latencies.html web manual. I want you to change MRG Kernel from ftrace to function for consistency in private. Thank you for interesting article Regards, GeunSik Lim.. 2009/4/7 Steven Rostedt : > > On Mon, 2009-04-06 at 23:02 +0900, GeunSik Lim wrote: >> Dear Steven, >> >> =C2=A0 =C2=A0The author of ftrace(Internal kernel Function Tracer) f= eature >> renamed the ftrace tracer >> =C2=A0 =C2=A0 to function to avoid further confusion between the ftr= ace >> infrastructure and the >> =C2=A0 =C2=A0 function tracer on Oct-20, 2008. >> >> =C2=A0 =C2=A0 But, Update of Mini-HOWTO document are still not worki= ng >> =C2=A0 =C2=A0 . >> =C2=A0 =C2=A0 Most of the developers often utilize "/debug/tracing/R= EADME" file >> as Mini-HOWTO. >> =C2=A0 =C2=A0 They will confuse definition and usage about ftrace =C2= =A0between >> README(ftrace) file >> =C2=A0 =C2=A0 and available_tracers(function) file after linux-2.6.2= 7 like me. >> =C2=A0 =C2=A0 And, I want you to append "chrt -f 5 sleep 1" command = as simple >> example for latency. >> >> =C2=A0 =C2=A0 Signed-off-by: GeunSik Lim >> =C2=A0 =C2=A0 Signed-off-by: Steven Rostedt >> =C2=A0 =C2=A0 Signed-off-by: Ingo Molnar >> --- >> =C2=A0kernel/trace/trace.c | =C2=A0 =C2=A03 ++- >> =C2=A01 files changed, 2 insertions(+), 1 deletions(-) >> >> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c >> index a0174a4..15f0eec 100644 >> --- a/kernel/trace/trace.c >> +++ b/kernel/trace/trace.c >> @@ -2358,7 +2358,7 @@ static const char readme_msg[] =3D >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "# mkdir /debug\n" >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "# mount -t debugfs nodev /debug\n\n" >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "# cat /debug/tracing/available_tracers\= n" >> - =C2=A0 =C2=A0 =C2=A0 "wakeup preemptirqsoff preemptoff irqsoff ftr= ace sched_switch none\n\n" >> + =C2=A0 =C2=A0 =C2=A0 "wakeup preemptirqsoff preemptoff irqsoff fun= ction >> sched_switch none\n\n" >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "# cat /debug/tracing/current_tracer\n" >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "none\n" >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "# echo sched_switch > /debug/tracing/cu= rrent_tracer\n" >> @@ -2368,6 +2368,7 @@ static const char readme_msg[] =3D >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "noprint-parent nosym-offset nosym-addr = noverbose\n" >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "# echo print-parent > /debug/tracing/tr= ace_options\n" >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "# echo 1 > /debug/tracing/tracing_enabl= ed\n" >> + =C2=A0 =C2=A0 =C2=A0 "# chrt -f 5 sleep 1\n" >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "# cat /debug/tracing/trace > /tmp/trace= =2Etxt\n" >> =C2=A0 =C2=A0 =C2=A0 =C2=A0 "echo 0 > /debug/tracing/tracing_enabled= \n" >> =C2=A0; >> > > Actually Nikanth sent a similar patch a month ago, but somehow it > slipped under the radar. I'll be picking that one up instead. > > http://lkml.org/lkml/2009/3/23/24 > > But thanks anyway. > > -- Steve > > > --=20 Regards, GeunSik Lim -- 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/ -- To unsubscribe from this list: send the line "unsubscribe linux-rt-user= s" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html