nmi, tracing: Make hardware latency tracing noinstr safe

The hardware latency tracer calls into instrumentable functions. Move the
calls into the RCU watching sections and annotate them.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20200521202116.904176298@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/hardirq.h

@@ -87,20 +87,24 @@ extern void rcu_nmi_exit(void);
 		arch_nmi_enter();				\
 		printk_nmi_enter();				\
 		lockdep_off();					\
-		ftrace_nmi_enter();				\
 		BUG_ON(in_nmi() == NMI_MASK);			\
 		__preempt_count_add(NMI_OFFSET + HARDIRQ_OFFSET);	\
 		rcu_nmi_enter();				\
 		lockdep_hardirq_enter();			\
+		instrumentation_begin();			\
+		ftrace_nmi_enter();				\
+		instrumentation_end();				\
 	} while (0)
 
 #define nmi_exit()						\
 	do {							\
+		instrumentation_begin();			\
+		ftrace_nmi_exit();				\
+		instrumentation_end();				\
 		lockdep_hardirq_exit();				\
 		rcu_nmi_exit();					\
 		BUG_ON(!in_nmi());				\
 		__preempt_count_sub(NMI_OFFSET + HARDIRQ_OFFSET);	\
-		ftrace_nmi_exit();				\
 		lockdep_on();					\
 		printk_nmi_exit();				\
 		arch_nmi_exit();				\