On Tue, 28 Sep 2021 09:11:06 +0900 Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote: I'm finally getting through my queue to see this. > Stop tracing before searching the pattern which is expected to > not exist on the trace buffer. In some case, it will take too > long and may not come back eternally because while searching > the tracing data will be increased by the searching activity. > > I found this with enabling kernel debug options, like kmemleak, > lockdep etc. and run it on qemu with 2 CPUs. It did not come > back in 20 minutes and finally I need to interrupt it to stop. One other option is to bring back the old behavior: echo 1 > options/pause-on-trace Which will stop tracing as the trace file is read. But either way works for me. -- Steve > > Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> > --- > .../ftrace/test.d/ftrace/func_profiler.tc | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_profiler.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func_profiler.tc > index 1dbd766c0cd2..440f4d87aa4b 100644 > --- a/tools/testing/selftests/ftrace/test.d/ftrace/func_profiler.tc > +++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_profiler.tc > @@ -56,6 +56,9 @@ clear_trace > sleep 1 > > echo "make sure something other than scheduler is being traced" > + > +echo 0 > tracing_on > + > if ! grep -v -e '^#' -e 'schedule' trace > /dev/null; then > cat trace > fail "no other functions besides schedule was found"
