[PATCH 2/2] selftests: ftrace: Add check for function-fork before running pid filter test

From: Steven Rostedt
Date: Tue Apr 18 2017 - 13:00:45 EST


From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>

Have the func-filter-pid test check for the function-fork option before
testing it. It can still test the pid filtering, but will stop before
testing the function-fork option for children inheriting the pids.
This allows the test to be added before the function-fork feature, but after
a bug fix that triggers one of the bugs the test can cause.

Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
.../ftrace/test.d/ftrace/func-filter-pid.tc | 27 ++++++++++++++++++----
1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-pid.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-pid.tc
index cd552f44c3b4..bab5ff7c607e 100644
--- a/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-pid.tc
+++ b/tools/testing/selftests/ftrace/test.d/ftrace/func-filter-pid.tc
@@ -19,10 +19,19 @@ if [ ! -f set_ftrace_filter ]; then
exit_unsupported
fi

+do_function_fork=1
+
+if [ ! -f options/function-fork ]; then
+ do_function_fork=0
+ echo "no option for function-fork found. Option will not be tested."
+fi
+
read PID _ < /proc/self/stat

-# default value of function-fork option
-orig_value=`grep function-fork trace_options`
+if [ $do_function_fork -eq 1 ]; then
+ # default value of function-fork option
+ orig_value=`grep function-fork trace_options`
+fi

do_reset() {
reset_tracer
@@ -31,6 +40,10 @@ do_reset() {
echo > set_ftrace_filter
echo > set_ftrace_pid

+ if [ $do_function_fork -eq 0 ]; then
+ return
+ fi
+
echo $orig_value > trace_options
}

@@ -53,8 +66,10 @@ do_test() {
echo $PID > set_ftrace_pid
echo function > current_tracer

- # don't allow children to be traced
- echo nofunction-fork > trace_options
+ if [ $do_function_fork -eq 1 ]; then
+ # don't allow children to be traced
+ echo nofunction-fork > trace_options
+ fi

enable_tracing
yield
@@ -70,6 +85,10 @@ do_test() {
disable_tracing
clear_trace

+ if [ $do_function_fork -eq 0 ]; then
+ return
+ fi
+
# allow children to be traced
echo function-fork > trace_options

--
2.10.2