On Fri, 13 Apr 2018 17:39:15 +0200 Steffen Maier <[email protected]> wrote:
> I fell into the trap of having set up function tracer with a very > limited filter and then switched over to function_graph and was > erroneously wondering why the latter did not trace what I expected, > which was the full unabridged graph recursion. > > Signed-off-by: Steffen Maier <[email protected]> > Cc: Steven Rostedt <[email protected]> Looks good. Reviewed-by: Steven Rostedt (VMware) <[email protected]> > Cc: Ingo Molnar <[email protected]> > Cc: Jonathan Corbet <[email protected]> Jon, you want to take it in your tree? -- Steve > Cc: [email protected] > --- > > Changes since v1: > Integrated review comments by Steven Rostedt > * less emotional phrasing > * also mention function profiling with set_ftrace_filter > (hopefully I got that right as I don't have experience with it) > > Documentation/trace/ftrace.rst | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/Documentation/trace/ftrace.rst b/Documentation/trace/ftrace.rst > index e45f0786f3f9..9bbd3aefadb2 100644 > --- a/Documentation/trace/ftrace.rst > +++ b/Documentation/trace/ftrace.rst > @@ -224,6 +224,8 @@ of ftrace. Here is a list of some of the key files: > has a side effect of enabling or disabling specific functions > to be traced. Echoing names of functions into this file > will limit the trace to only those functions. > + This influences the tracers "function" and "function_graph" > + and thus also function profiling (see "function_profile_enabled"). > > The functions listed in "available_filter_functions" are what > can be written into this file. > @@ -265,6 +267,8 @@ of ftrace. Here is a list of some of the key files: > Functions listed in this file will cause the function graph > tracer to only trace these functions and the functions that > they call. (See the section "dynamic ftrace" for more details). > + Note, set_ftrace_filter and set_ftrace_notrace still affects > + what functions are being traced. > > set_graph_notrace: > > @@ -277,7 +281,8 @@ of ftrace. Here is a list of some of the key files: > > This lists the functions that ftrace has processed and can trace. > These are the function names that you can pass to > - "set_ftrace_filter" or "set_ftrace_notrace". > + "set_ftrace_filter", "set_ftrace_notrace", > + "set_graph_function", or "set_graph_notrace". > (See the section "dynamic ftrace" below for more details.) > > dyn_ftrace_total_info: -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
