From a05ffdce7155769ea5ac3409e1490fb9116dbaed Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Mon, 30 Mar 2015 16:21:40 +1100 Subject: ftracetest: Cope properly with stack tracer not being enabled If the stack tracer (CONFIG_STACK_TRACER) is disabled, the fgraph-filter-stack test blows chunks: [8] ftrace - function graph filters with stack tracer [FAIL] + reset_tracer + echo nop ./ftracetest: 19: /home/michael/selftests/ftrace/test.d/ftrace/fgraph-filter-stack.tc: cannot create /proc/sys/kernel/stack_tracer_enabled: Directory nonexistent Fix it by checking if the proc file exists before echoing to it. With the patch applied it fails correctly with: [8] ftrace - function graph filters with stack tracer [UNSUPPORTED] Signed-off-by: Michael Ellerman Acked-by: Steven Rostedt Signed-off-by: Shuah Khan --- tools/testing/selftests/ftrace/test.d/ftrace/fgraph-filter-stack.tc | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'tools/testing/selftests/ftrace') diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-filter-stack.tc b/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-filter-stack.tc index c15e018e0220..3b1cf20cf6d8 100644 --- a/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-filter-stack.tc +++ b/tools/testing/selftests/ftrace/test.d/ftrace/fgraph-filter-stack.tc @@ -16,7 +16,9 @@ fi do_reset() { reset_tracer - echo 0 > /proc/sys/kernel/stack_tracer_enabled + if [ -e /proc/sys/kernel/stack_tracer_enabled ]; then + echo 0 > /proc/sys/kernel/stack_tracer_enabled + fi enable_tracing clear_trace echo > set_ftrace_filter -- cgit v1.2.3-55-g7522