[patch-rt 5/5] trace: warn if irqs already enabled in irqs_off latency check

[Thomas Gleixner <tglx@linutronix.de>]

[-- Attachment #1: warn-if-irqs-already-enabled-in-irqs-off-latency-check.patch --]
[-- Type: text/plain, Size: 892 bytes --]

Be consistent: Warn if irqs are already enabled in irqs_off latency
processing, same as in preempt_off and in irqs_off && preempt_off. This
warning can now safely be inserted, after a problem was fixed that
caused false positives.

Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>


---
 kernel/trace/trace_hist.c |    1 +
 1 file changed, 1 insertion(+)

Index: linux-2.6.26.8/kernel/trace/trace_hist.c
===================================================================
--- linux-2.6.26.8.orig/kernel/trace/trace_hist.c
+++ linux-2.6.26.8/kernel/trace/trace_hist.c
@@ -356,6 +356,7 @@ notrace void tracing_hist_preempt_stop(i
 #ifdef CONFIG_INTERRUPT_OFF_HIST
 	if (irqs_on &&
 	    per_cpu(hist_irqsoff_tracing, cpu)) {
+		WARN_ON(!irqs_disabled());
 		stop = ftrace_now(cpu);
 		stop_set++;
 		start = per_cpu(hist_irqsoff_start, cpu);