[PATCH v2 10/15] perf ftrace: add support for trace option sleep-time

[Changbin Du]

This adds an option '--graph-nosleep-time' which allow us only to measure
on-CPU time. This option is function_graph tracer only.

Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx>

---
v2: option name '--nosleep-time' -> '--graph-nosleep-time'.
---
 tools/perf/Documentation/perf-ftrace.txt |  3 +++
 tools/perf/builtin-ftrace.c              | 20 ++++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/tools/perf/Documentation/perf-ftrace.txt b/tools/perf/Documentation/perf-ftrace.txt
index 94cdb2ebdf34..a3000436f80b 100644
--- a/tools/perf/Documentation/perf-ftrace.txt
+++ b/tools/perf/Documentation/perf-ftrace.txt
@@ -104,6 +104,9 @@ OPTIONS
 --graph-depth=::
 	Set max depth for function graph tracer to follow
 
+--graph-nosleep-time::
+	Measure on-CPU time only for function_graph tracer.
+
 SEE ALSO
 --------
 linkperf:perf-record[1], linkperf:perf-trace[1]
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index bbfa7973b4fa..eba125a60820 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -42,6 +42,7 @@ struct perf_ftrace {
 	unsigned		buffer_size_kb;
 	bool			inherit;
 	bool			func_stack_trace;
+	bool			graph_nosleep_time;
 };
 
 struct filter_entry {
@@ -200,6 +201,7 @@ static void reset_tracing_options(struct perf_ftrace *ftrace __maybe_unused)
 {
 	write_tracing_option_file("function-fork", "0");
 	write_tracing_option_file("func_stack_trace", "0");
+	write_tracing_option_file("sleep-time", "1");
 }
 
 static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused)
@@ -380,6 +382,17 @@ static int set_tracing_trace_inherit(struct perf_ftrace *ftrace)
 	return 0;
 }
 
+static int set_tracing_sleep_time(struct perf_ftrace *ftrace)
+{
+	if (!ftrace->graph_nosleep_time)
+		return 0;
+
+	if (write_tracing_option_file("sleep-time", "0") < 0)
+		return -1;
+
+	return 0;
+}
+
 static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
 {
 	char *trace_file;
@@ -459,6 +472,11 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv)
 		goto out_reset;
 	}
 
+	if (set_tracing_sleep_time(ftrace) < 0) {
+		pr_err("failed to set tracing option sleep-time\n");
+		goto out_reset;
+	}
+
 	if (write_tracing_file("current_tracer", ftrace->tracer) < 0) {
 		pr_err("failed to set current_tracer to %s\n", ftrace->tracer);
 		goto out_reset;
@@ -638,6 +656,8 @@ int cmd_ftrace(int argc, const char **argv)
 		     "size of per cpu buffer in kb"),
 	OPT_BOOLEAN(0, "inherit", &ftrace.inherit,
 		    "trace children processes"),
+	OPT_BOOLEAN(0, "graph-nosleep-time", &ftrace.graph_nosleep_time,
+		    "measure on-CPU time only for function_graph tracer"),
 	OPT_END()
 	};
 
-- 
2.25.1