tracing: irqsoff: Account for additional preempt_disable

[sfrench/cifs-2.6.git] / kernel / trace / trace_irqsoff.c

diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 770cd30cda40158b2bf3f2fd697070d8777b233f..ffbf1505d5bcb8c1b0865e814f89068c0fa5a74f 100644 (file)
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -603,14 +603,40 @@ static void irqsoff_tracer_stop(struct trace_array *tr)
  */
 static void tracer_hardirqs_on(void *none, unsigned long a0, unsigned long a1)
 {
+       /*
+        * Tracepoint probes are expected to be called with preempt disabled,
+        * We don't care about being called with preempt disabled but we need
+        * to know in the future if that changes so we can remove the next
+        * preempt_enable.
+        */
+       WARN_ON_ONCE(!preempt_count());
+
+       /* Tracepoint probes disable preemption atleast once, account for that */
+       preempt_enable_notrace();
+
        if (!preempt_trace() && irq_trace())
                stop_critical_timing(a0, a1);
+
+       preempt_disable_notrace();
 }
 
 static void tracer_hardirqs_off(void *none, unsigned long a0, unsigned long a1)
 {
+       /*
+        * Tracepoint probes are expected to be called with preempt disabled,
+        * We don't care about being called with preempt disabled but we need
+        * to know in the future if that changes so we can remove the next
+        * preempt_enable.
+        */
+       WARN_ON_ONCE(!preempt_count());
+
+       /* Tracepoint probes disable preemption atleast once, account for that */
+       preempt_enable_notrace();
+
        if (!preempt_trace() && irq_trace())
                start_critical_timing(a0, a1);
+
+       preempt_disable_notrace();
 }
 
 static int irqsoff_tracer_init(struct trace_array *tr)