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authorSteven Rostedt (Red Hat) <rostedt@goodmis.org>2013-04-30 15:46:14 -0400
committerSteven Rostedt <rostedt@goodmis.org>2013-06-11 18:38:46 -0400
commitad71d889b88055e61e3970a6744a271a51a94f42 (patch)
tree716f6e043847000a82449270e3b2d5dcdc9c4f79 /Documentation/trace
parent317ddd256b9c24b0d78fa8018f80f1e495481a10 (diff)
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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: <function>: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 <lclaudio@uudg.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'Documentation/trace')
-rw-r--r--Documentation/trace/ftrace.txt7
1 files changed, 7 insertions, 0 deletions
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
----------