From: "Steven Rostedt (VMware)" rostedt@goodmis.org

The ftrace selftest "ftrace - test for function traceon/off triggers" enables all events and reads the trace file. Now that the trace file does not disable tracing, and will attempt to continually read new data that is added, the selftest gets stuck reading the trace file. This is because the data added to the trace file will fill up quicker than the reading of it.

By only enabling scheduling events, the read can keep up with the writes. Instead of enabling all events, only enable the scheduler events.

Link: http://lkml.kernel.org/r/20200318111345.0516642e@gandalf.local.home

Cc: Shuah Khan skhan@linuxfoundation.org Cc: linux-kselftest@vger.kernel.org Acked-by: Masami Hiramatsu mhiramat@kernel.org Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org --- .../selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc index 0c04282d33dd..1947387fe976 100644 --- a/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc +++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc @@ -41,7 +41,7 @@ fi

echo '** ENABLE EVENTS'

-echo 1 > events/enable +echo 1 > events/sched/enable

echo '** ENABLE TRACING' enable_tracing