ftrace: give time for wakeup test to run

It is possible that the testing thread in the ftrace wakeup test does not
run before we stop the trace. This will cause the trace to fail since nothing
will be in the buffers.

This patch adds a small wait in the wakeup test to allow for the woken task
to run and be traced.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 82db9103b9bc10f726a5d80b2af614fffa281dbd..5ebd4b13549847cf590697bf6238d95d7e5bd228 100644 (file)
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -498,6 +498,9 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
 
        wake_up_process(p);
 
+       /* give a little time to let the thread wake up */
+       msleep(100);
+
        /* stop the tracing. */
        tr->ctrl = 0;
        trace->ctrl_update(tr);