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 problem. 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/Realtime_Tuning_Guide/sect-Realtime_Tuning_Guide-Realtime_Specific_Tuning-Using_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 <srostedt@xxxxxxxxxx>: > > On Mon, 2009-04-06 at 23:02 +0900, GeunSik Lim wrote: >> 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 <leemgs1@xxxxxxxxx> >> Signed-off-by: Steven Rostedt <srostedt@xxxxxxxxxx> >> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> >> --- >> 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" >> "# cat /debug/tracing/trace > /tmp/trace.txt\n" >> "echo 0 > /debug/tracing/tracing_enabled\n" >> ; >> > > 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 > > > -- Regards, GeunSik Lim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@xxxxxxxxxxxxxxx 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-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
