[PATCH 01/12 v2] selftest/ftrace: Fix function trigger test to handle trace not disabling the tracer

From: Steven Rostedt
Date: Thu Mar 19 2020 - 19:27:37 EST


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

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@xxxxxxxxxxxxxxxxxx

Cc: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
Cc: linux-kselftest@xxxxxxxxxxxxxxx
Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
.../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
--
2.25.1