tracing/function-graph-tracer: provide a selftest for the function graph tracer
Making it more easy to do a basic regression test for this tracer.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index b9838f4..a011ec0 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -500,6 +500,8 @@
#ifdef CONFIG_FTRACE_STARTUP_TEST
extern int trace_selftest_startup_function(struct tracer *trace,
struct trace_array *tr);
+extern int trace_selftest_startup_function_graph(struct tracer *trace,
+ struct trace_array *tr);
extern int trace_selftest_startup_irqsoff(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_preemptoff(struct tracer *trace,
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 222f97d..88f8d9d 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -750,6 +750,9 @@
.print_line = print_graph_function,
.print_header = print_graph_headers,
.flags = &tracer_flags,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_function_graph,
+#endif
};
static __init int init_graph_trace(void)
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 445700e..0c9aa14 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -13,6 +13,8 @@
case TRACE_PRINT:
case TRACE_SPECIAL:
case TRACE_BRANCH:
+ case TRACE_GRAPH_ENT:
+ case TRACE_GRAPH_RET:
return 1;
}
return 0;
@@ -227,6 +229,54 @@
}
#endif /* CONFIG_FUNCTION_TRACER */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+/*
+ * Pretty much the same than for the function tracer from which the selftest
+ * has been borrowed.
+ */
+int
+trace_selftest_startup_function_graph(struct tracer *trace,
+ struct trace_array *tr)
+{
+ int ret;
+ unsigned long count;
+
+ ret = tracer_init(trace, tr);
+ if (ret) {
+ warn_failed_init_tracer(trace, ret);
+ goto out;
+ }
+
+ /* Sleep for a 1/10 of a second */
+ msleep(100);
+
+ tracing_stop();
+
+ /* check the trace buffer */
+ ret = trace_test_buffer(tr, &count);
+
+ trace->reset(tr);
+ tracing_start();
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ goto out;
+ }
+
+ /* Don't test dynamic tracing, the function tracer already did */
+
+out:
+ /* Stop it if we failed */
+ if (ret)
+ ftrace_graph_stop();
+
+ return ret;
+}
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+
#ifdef CONFIG_IRQSOFF_TRACER
int
trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
