tracing/ftrace: don't insert TRACE_PRINT during selftests

unsigned long __read_mostly	tracing_max_latency = (cycle_t)ULONG_MAX;

unsigned long __read_mostly	tracing_thresh;

/* We need to change this state when a selftest is running.

 * A selftest will lurk into the ring-buffer to count the

 * entries inserted during the selftest although some concurrent

 * insertions into the ring-buffer such as ftrace_printk could occurred

 * at the same time, giving false positive or negative results.

 */

static atomic_t tracing_selftest_running = ATOMIC_INIT(0);

/* For tracers that don't implement custom flags */

static struct tracer_opt dummy_tracer_opt[] = {

	{ }

		struct tracer *saved_tracer = current_trace;

		struct trace_array *tr = &global_trace;

		int i;

		atomic_set(&tracing_selftest_running, 1);

		/*

		 * Run a selftest on this tracer.

		 * Here we reset the trace buffer, and set the current

		/* the test is responsible for initializing and enabling */

		pr_info("Testing tracer %s: ", type->name);

		ret = type->selftest(type, tr);

		atomic_set(&tracing_selftest_running, 0);

		/* the test is responsible for resetting too */

		current_trace = saved_tracer;

		if (ret) {

	unsigned long flags, irq_flags;

	int cpu, len = 0, size, pc;

	if (tracing_disabled)

	if (tracing_disabled || atomic_read(&tracing_selftest_running))

		return 0;

	pc = preempt_count();