From ad71d889b88055e61e3970a6744a271a51a94f42 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Tue, 30 Apr 2013 15:46:14 -0400 Subject: tracing: Add function probe to trigger a ftrace dump to console Add the "dump" command to have the 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. Format is: :dump echo 'bad_address:dump' > /debug/tracing/set_ftrace_filter To remove this: echo '!bad_address:dump' > /debug/tracing/set_ftrace_filter Requested-by: Luis Claudio R. Goncalves Signed-off-by: Steven Rostedt --- Documentation/trace/ftrace.txt | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'Documentation/trace/ftrace.txt') diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt index bfe8c29b1f1d..cc9ec57e157c 100644 --- a/Documentation/trace/ftrace.txt +++ b/Documentation/trace/ftrace.txt @@ -2430,6 +2430,13 @@ The following commands are supported: echo '!schedule:disable_event:sched:sched_switch' > \ set_ftrace_filter +- dump + When the function is hit, it will dump the contents of the ftrace + ring buffer to the console. This is useful if you need to debug + something, and want to dump the trace when a certain function + is hit. Perhaps its a function that is called before a tripple + fault happens and does not allow you to get a regular dump. + trace_pipe ---------- -- cgit v1.2.3