When using the function or function_graph tracers from the command line, certain command line options have limitations.
Document that only kernel built-in functions can be filtered via ftrace_filter= or ftrace_graph_filter=. Also document that tracer- specific options cannot be set on the command line via trace_options. Signed-off-by: Peter Hurley <[email protected]> --- Documentation/kernel-parameters.txt | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 4c81a86..6f9dfa0 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1121,6 +1121,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. list of functions. This list can be changed at run time by the set_ftrace_filter file in the debugfs tracing directory. + Only built-in functions can be traced when specified + this way. ftrace_notrace=[function-list] [FTRACE] Do not trace the functions specified in @@ -1134,6 +1136,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. function-list is a comma separated list of functions that can be changed at run time by the set_graph_function file in the debugfs tracing directory. + Only built-in functions can be traced when specified + this way. ftrace_graph_notrace=[function-list] [FTRACE] Do not trace from the functions specified in @@ -3521,6 +3525,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. trace_options=stacktrace + Tracer-specific options are ignored when set this way. + For example, the 'func_stack_trace' option cannot be + set here. + See also Documentation/trace/ftrace.txt "trace options" section. -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
