[PATCH 4/4] tracing: Only trace sched_wakeup if it actually work something up

[Steven Rostedt]

From: Steven Rostedt <srostedt@xxxxxxxxxx>

Currently the tracepoint sched_wakeup traces the wakeup event even
if the wakeup failed to wake anything up. This is quite stupid
but it happens because we did not want to add a conditional
to the core kernel code that would just slow down the wakeup events.

This patch changes the wakeup tracepoints to use the

 DEFINE_EVENT_CONDITIONAL()

to test the "success" parameter and will only trace the event if
the wakeup was successfull.

The success field in the tracepoint is removed since it is no
longer needed.

Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
 include/trace/events/sched.h |   16 ++++++++--------
 1 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index f633478..29e6030 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -62,7 +62,6 @@ DECLARE_EVENT_CLASS(sched_wakeup_template,
 		__array(	char,	comm,	TASK_COMM_LEN	)
 		__field(	pid_t,	pid			)
 		__field(	int,	prio			)
-		__field(	int,	success			)
 		__field(	int,	target_cpu		)
 	),
 
@@ -70,25 +69,26 @@ DECLARE_EVENT_CLASS(sched_wakeup_template,
 		memcpy(__entry->comm, p->comm, TASK_COMM_LEN);
 		__entry->pid		= p->pid;
 		__entry->prio		= p->prio;
-		__entry->success	= success;
 		__entry->target_cpu	= task_cpu(p);
 	),
 
-	TP_printk("comm=%s pid=%d prio=%d success=%d target_cpu=%03d",
+	TP_printk("comm=%s pid=%d prio=%d target_cpu=%03d",
 		  __entry->comm, __entry->pid, __entry->prio,
-		  __entry->success, __entry->target_cpu)
+		  __entry->target_cpu)
 );
 
-DEFINE_EVENT(sched_wakeup_template, sched_wakeup,
+DEFINE_EVENT_CONDITION(sched_wakeup_template, sched_wakeup,
 	     TP_PROTO(struct task_struct *p, int success),
-	     TP_ARGS(p, success));
+	     TP_ARGS(p, success),
+	     TP_CONDITION(success));
 
 /*
  * Tracepoint for waking up a new task:
  */
-DEFINE_EVENT(sched_wakeup_template, sched_wakeup_new,
+DEFINE_EVENT_CONDITION(sched_wakeup_template, sched_wakeup_new,
 	     TP_PROTO(struct task_struct *p, int success),
-	     TP_ARGS(p, success));
+	     TP_ARGS(p, success),
+	     TP_CONDITION(success));
 
 #ifdef CREATE_TRACE_POINTS
 static inline long __trace_sched_switch_state(struct task_struct *p)
-- 
1.7.2.3


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