[PATCH v2 2/3] perf ftrace: Add --graph-opts option to profile subcommand

[Namhyung Kim <namhyung@kernel.org>]

Like trace subcommand, it should be able to pass some options to control
the tracing behavior for the function graph tracer.  But some options
are limited in order to maintain the internal behavior.

For example, it can limit the function call depth like below:

  # perf ftrace profile --graph-opts depth=5 -- myprog

Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/Documentation/perf-ftrace.txt | 8 ++++++++
 tools/perf/builtin-ftrace.c              | 4 ++++
 2 files changed, 12 insertions(+)

diff --git a/tools/perf/Documentation/perf-ftrace.txt b/tools/perf/Documentation/perf-ftrace.txt
index eccc0483f7faecad..b77f58c4d2fdcff9 100644
--- a/tools/perf/Documentation/perf-ftrace.txt
+++ b/tools/perf/Documentation/perf-ftrace.txt
@@ -201,6 +201,14 @@ OPTIONS for 'perf ftrace profile'
 	Sort the result by the given field.  Available values are:
 	total, avg, max, count, name.  Default is 'total'.
 
+--graph-opts::
+	List of options allowed to set:
+
+	  - nosleep-time - Measure on-CPU time only for function_graph tracer.
+	  - noirqs       - Ignore functions that happen inside interrupt.
+	  - thresh=<n>   - Setup trace duration threshold in microseconds.
+	  - depth=<n>    - Set max depth for function graph tracer to follow.
+
 
 SEE ALSO
 --------
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index 2a786047ba32bcb7..08c1cc429b27e169 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -1064,6 +1064,7 @@ static int prepare_func_profile(struct perf_ftrace *ftrace)
 {
 	ftrace->tracer = "function_graph";
 	ftrace->graph_tail = 1;
+	ftrace->graph_verbose = 0;
 
 	ftrace->profile_hash = hashmap__new(profile_hash, profile_equal, NULL);
 	if (ftrace->profile_hash == NULL)
@@ -1650,6 +1651,9 @@ int cmd_ftrace(int argc, const char **argv)
 	OPT_CALLBACK('s', "sort", &profile_sort, "key",
 		     "Sort result by key: total (default), avg, max, count, name.",
 		     parse_sort_key),
+	OPT_CALLBACK(0, "graph-opts", &ftrace, "options",
+		     "Graph tracer options, available options: nosleep-time,noirqs,thresh=<n>,depth=<n>",
+		     parse_graph_tracer_opts),
 	OPT_PARENT(common_options),
 	};
 	const struct option *options = ftrace_options;
-- 
2.47.1.613.gc27f4b7a9f-goog