[PATCH] Update old Mini-HOWTO for ftrace

[GeunSik Lim <leemgs1@gmail.com>]

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   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@gmail.com>
    Signed-off-by: Steven Rostedt <srostedt@redhat.com>
    Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 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"
 ;



-- 
Regards,
GeunSik Lim
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Author: GeunSik  Lim<leemgs1@gmail.com>
Date:   Mon Apr 6 22:48:16 2009 +0900

    [PATCH] Update Mini-HOWTO for ftrace
    
    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@gmail.com>
    Signed-off-by: Steven Rostedt <srostedt@redhat.com>
    Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 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"
 ;