tracing: timer: Add deferrable flag to timer_start

The timer_start event now shows whether the timer is deferrable in case of a low-res timer. The debug_activate function now includes deferrable flag while calling trace_timer_start event.

Signed-off-by Badhri Jagan Sridharan <[email protected]>

---
Changelog since v1:
- fixed indentation
- moved deferrable flag checking to tracing code

  include/trace/events/timer.h | 14 +++++++++-----
  kernel/time/timer.c          |  3 ++-
  2 files changed, 11 insertions(+), 6 deletions(-)

include/trace/events/timer.h +9 -5

index 68c2c20..e69bb03 100644
@@ -43,15 +43,17 @@ DEFINE_EVENT(timer_class, timer_init,
   */
  TRACE_EVENT(timer_start,
 
-	TP_PROTO(struct timer_list *timer, unsigned long expires),
+	TP_PROTO(struct timer_list *timer,
+		unsigned long expires, char deferrable),
 
-	TP_ARGS(timer, expires),
+	TP_ARGS(timer, expires, deferrable),
 
  	TP_STRUCT__entry(
  		__field( void *,	timer		)
  		__field( void *,	function	)
  		__field( unsigned long,	expires		)
  		__field( unsigned long,	now		)
+		__field( char,		deferrable	)
  	),
 
  	TP_fast_assign(

@@ -59,11 +61,13 @@ TRACE_EVENT(timer_start,
  		__entry->function	= timer->function;
  		__entry->expires	= expires;
  		__entry->now		= jiffies;
+		__entry->deferrable     = deferrable;
  	),
 
-	TP_printk("timer=%p function=%pf expires=%lu [timeout=%ld]",
-		  __entry->timer, __entry->function, __entry->expires,
-		  (long)__entry->expires - __entry->now)
+	TP_printk("timer=%p function=%pf expires=%lu [timeout=%ld] defer=%c",
+		__entry->timer, __entry->function, __entry->expires,
+		(long)__entry->expires - __entry->now,
+		__entry->deferrable > 0 ? 'y':'n')
  );
 
  /**

kernel/time/timer.c +2 -1

index 2ece3aa..e5588da 100644
@@ -648,7 +648,8 @@ static inline void
  debug_activate(struct timer_list *timer, unsigned long expires)
  {
  	debug_timer_activate(timer);
-	trace_timer_start(timer, expires);
+	trace_timer_start(timer, expires,
+		tbase_get_deferrable(timer->base));
  }
 
  static inline void debug_deactivate(struct timer_list *timer)