[PATCH v8 8/8] selftests/ftrace: Add funcgraph-retval test case

[Donglin Peng <pengdonglin@sangfor.com.cn>]

Add a test case for the funcgraph-retval and funcgraph-retval-hex
trace options.

Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn>
---
v8:
 - Fix issues in selftest
---
 .../ftrace/test.d/ftrace/fgraph-retval.tc     | 39 +++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 tools/testing/selftests/ftrace/test.d/ftrace/fgraph-retval.tc

diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-retval.tc b/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-retval.tc
new file mode 100644
index 000000000000..ac6d0183e4d9
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-retval.tc
@@ -0,0 +1,39 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: ftrace - function graph print function return value
+# requires: set_graph_function options/funcgraph-retval options/funcgraph-retval-hex function_graph:tracer
+
+# Make sure that funcgraph-retval works
+
+fail() { # msg
+    echo $1
+    exit_fail
+}
+
+echo proc_reg_write > set_graph_function
+echo function_graph > current_tracer
+echo funcgraph-retval > trace_options
+
+enable_tracing
+
+set +e
+echo > /proc/interrupts
+set -e
+
+disable_tracing
+
+: "Test printing the error code in signed decimal format"
+echo nofuncgraph-retval-hex > trace_options
+count=`cat trace | grep 'proc_reg_write' | grep '= -5' | wc -l`
+if [ $count -eq 0 ]; then
+    fail "Return value can not be printed in signed decimal format"
+fi
+
+: "Test printing the error code in hexadecimal format"
+echo funcgraph-retval-hex > trace_options
+count=`cat trace | grep 'proc_reg_write' | grep 'fffffffb' | wc -l`
+if [ $count -eq 0 ]; then
+    fail "Return value can not be printed in hexadecimal format"
+fi
+
+exit 0
-- 
2.25.1