On Fri, 17 Aug 2018 01:40:30 +0900 Masami Hiramatsu <mhira...@kernel.org> wrote:
> Add a testcase for max stack tracer, which checks basic > max stack usage tracing and its filter feature. > > Signed-off-by: Masami Hiramatsu <mhira...@kernel.org> > --- > .../ftrace/test.d/ftrace/func_stack_tracer.tc | 39 > ++++++++++++++++++++ > 1 file changed, 39 insertions(+) > create mode 100644 > tools/testing/selftests/ftrace/test.d/ftrace/func_stack_tracer.tc > > diff --git > a/tools/testing/selftests/ftrace/test.d/ftrace/func_stack_tracer.tc > b/tools/testing/selftests/ftrace/test.d/ftrace/func_stack_tracer.tc > new file mode 100644 > index 000000000000..b414f0e3c646 > --- /dev/null > +++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_stack_tracer.tc > @@ -0,0 +1,39 @@ > +#!/bin/sh > +# SPDX-License-Identifier: GPL-2.0 > +# description: ftrace - Max stack tracer > +# Test the basic function of max-stack usage tracing > + > +if [ ! -f stack_trace ]; then > + echo "Max stack tracer is not supported - please make > CONFIG_STACK_TRACER=y" > + exit_unsupported > +fi > + > +echo > stack_trace_filter > +echo 0 > stack_max_size > +echo 1 > /proc/sys/kernel/stack_tracer_enabled > + > +: "Fork and wait for the first entry become !lock" > +timeout=10 > +while [ $timeout -ne 0 ]; do > + ( echo "forked" ) > + FL=`grep " 0)" stack_trace` > + echo $FL | grep -q "lock" || break; > + timeout=$((timeout - 1)) > +done > +echo 0 > /proc/sys/kernel/stack_tracer_enabled > + > +echo '*lock*' > stack_trace_filter > +test `cat stack_trace_filter | wc -l` -eq `grep lock stack_trace_filter | wc > -l` > + > +echo 0 > stack_max_size > +echo 1 > /proc/sys/kernel/stack_tracer_enabled This test fails quite a bit because it doesn't guarantee that another stack trace gets in that is bigger, and we don't find the "lock". -- Steve > + > +: "Fork and always the first entry including lock" > +timeout=10 > +while [ $timeout -ne 0 ]; do > + ( echo "forked" ) > + FL=`grep " 0)" stack_trace` > + echo $FL | grep -q "lock" > + timeout=$((timeout - 1)) > +done > +echo 0 > /proc/sys/kernel/stack_tracer_enabled
