Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754827AbZDGB1h (ORCPT ); Mon, 6 Apr 2009 21:27:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752299AbZDGB1Y (ORCPT ); Mon, 6 Apr 2009 21:27:24 -0400 Received: from mx2.redhat.com ([66.187.237.31]:51324 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750994AbZDGB1X (ORCPT ); Mon, 6 Apr 2009 21:27:23 -0400 Subject: Re: [PATCH] Update old Mini-HOWTO for ftrace From: Steven Rostedt To: GeunSik Lim Cc: Ingo Molnar , rt-users , "linux-kernel@vger.kernel.org" In-Reply-To: <49b7c2350904060717l1a87cca7p880b6843ea92c702@mail.gmail.com> References: <49b7c2350904060702j3f725a45ub5e7d3ee3af883c1@mail.gmail.com> <49b7c2350904060717l1a87cca7p880b6843ea92c702@mail.gmail.com> Content-Type: text/plain Organization: Red Hat Date: Mon, 06 Apr 2009 21:26:56 -0400 Message-Id: <1239067616.4753.12.camel@localhost.localdomain> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2790 Lines: 76 On Mon, 2009-04-06 at 23:17 +0900, GeunSik Lim wrote: > I attached patch file again because no-operation is changed > from "none"word to "nop" word. > > for example, > - "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" > + "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" > > ./trace_nop.c:struct tracer nop_trace __read_mostly = > .name = "nop", > .init = nop_trace_init, > .reset = nop_trace_reset, > .selftest = trace_selftest_startup_nop, > .flags = &nop_flags, > .set_flag = nop_set_flag > > > > 2009/4/6 GeunSik Lim : > > Dear Steven, > > > > The author of ftrace(Internal kernel Function Tracer) feature > > renamed the ftrace tracer > > to function to avoid further confusion between the ftrace > > infrastructure and the > > function tracer on Oct-20, 2008. > > > > But, Update of Mini-HOWTO document are still not working > > . > > Most of the developers often utilize "/debug/tracing/README" file > > as Mini-HOWTO. > > They will confuse definition and usage about ftrace between > > README(ftrace) file > > and available_tracers(function) file after linux-2.6.27 like me. > > And, I want you to append "chrt -f 5 sleep 1" command as simple > > example for latency. > > > > Signed-off-by: GeunSik Lim > > Signed-off-by: Steven Rostedt > > Signed-off-by: Ingo Molnar > > --- > > kernel/trace/trace.c | 3 ++- > > 1 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[] = > > "# mkdir /debug\n" > > "# mount -t debugfs nodev /debug\n\n" > > "# cat /debug/tracing/available_tracers\n" > > - "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" > > + "wakeup preemptirqsoff preemptoff irqsoff function > > sched_switch none\n\n" > > "# cat /debug/tracing/current_tracer\n" > > "none\n" > > "# echo sched_switch > /debug/tracing/current_tracer\n" > > @@ -2368,6 +2368,7 @@ static const char readme_msg[] = > > "noprint-parent nosym-offset nosym-addr noverbose\n" > > "# echo print-parent > /debug/tracing/trace_options\n" > > "# echo 1 > /debug/tracing/tracing_enabled\n" > > + "# chrt -f 5 sleep 1\n" What's the chrt for? -- Steve -- 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/