ftrace: timestamp syncing, prepare

rename and uninline now() to ftrace_now().

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 5d8ad7a..e5d34b7 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -20,7 +20,7 @@
 {
 	int cpu;
 
-	tr->time_start = now(tr->cpu);
+	tr->time_start = ftrace_now(tr->cpu);
 
 	for_each_online_cpu(cpu)
 		tracing_reset(tr->data[cpu]);