On Wed, 6 Sep 2023 19:57:24 +0800 Zheng Yejian <zhengyejian1@xxxxxxxxxx> wrote: > BTW, I do reproduce with following testcase fix, then just run: > ./ftracetest test.d/instances/instance-event.tc > diff --git > a/tools/testing/selftests/ftrace/test.d/instances/instance-event.tc > b/tools/testing/selftests/ftrace/test.d/instances/instance-event.tc > index 0eb47fbb3f44..42422e425107 100644 > --- a/tools/testing/selftests/ftrace/test.d/instances/instance-event.tc > +++ b/tools/testing/selftests/ftrace/test.d/instances/instance-event.tc > @@ -39,7 +39,7 @@ instance_read() { > > instance_set() { > while :; do > - echo 1 > foo/events/sched/sched_switch > + echo 1 > foo/events/sched/sched_switch/enable > done 2> /dev/null > } Ah thanks. I didn't have that on my test box :-p Although I'm still having issues reproducing it. Do you have anything special on your kernel command line? -- Steve