From: Arnd Bergmann After trace_selftest_startup_sched_switch is removed, trace_test_buffer() is only used sometimes, leading to this warning: kernel/trace/trace_selftest.c:62:12: error: 'trace_test_buffer' defined but not used [-Werror=unused-function] There is no simple #ifdef condition that captures well whether the function is in fact used or not, so marking it as __maybe_unused is probably the best way to shut up the warning. The function will then be silently dropped when there is no user. Link: http://lkml.kernel.org/r/20171013142227.1273469-1-arnd@arndb.de Fixes: d8c4deee6dc6 ("tracing: Remove obsolete sched_switch tracer selftest") Signed-off-by: Arnd Bergmann Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_selftest.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index 364f78abdf47..eb9ba5c1ba40 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -59,7 +59,7 @@ static int trace_test_buffer_cpu(struct trace_buffer *buf, int cpu) * Test the trace buffer to see if all the elements * are still sane. */ -static int trace_test_buffer(struct trace_buffer *buf, unsigned long *count) +static int __maybe_unused trace_test_buffer(struct trace_buffer *buf, unsigned long *count) { unsigned long flags, cnt = 0; int cpu, ret = 0; -- 2.13.2