tree a37db37999a01fb1f425a19f5a9615faf1059b73
parent ad71d889b88055e61e3970a6744a271a51a94f42
author Steven Rostedt (Red Hat) <rostedt@goodmis.org> 1367362846 -0400
committer Steven Rostedt <rostedt@goodmis.org> 1370990328 -0400

tracing: Add function probe to trigger a ftrace dump of current CPU trace

Add the "cpudump" command to have the current CPU ftrace buffer dumped
to console if a function is hit. This is useful when debugging a
tripple fault, where you have an idea of a function that is called
just before the tripple fault occurs, and can tell ftrace to dump its
content out to the console before it continues.

This differs from the "dump" command as it only dumps the content of
the ring buffer for the currently executing CPU, and does not show
the contents of the other CPUs.

Format is:

  <function>:cpudump

echo 'bad_address:cpudump' > /debug/tracing/set_ftrace_filter

To remove this:

echo '!bad_address:cpudump' > /debug/tracing/set_ftrace_filter

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>