sched: add latency tracer callbacks to the scheduler

add 3 lightweight callbacks to the tracer backend.

zero impact if tracing is turned off.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index cfa222a91539..463dcdb36ef8 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2467,6 +2467,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
 
 out_activate:
 #endif /* CONFIG_SMP */
+        ftrace_wake_up_task(p, rq->curr);
         schedstat_inc(p, se.nr_wakeups);
         if (sync)
                 schedstat_inc(p, se.nr_wakeups_sync);
@@ -2611,6 +2612,7 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
                 p->sched_class->task_new(rq, p);
                 inc_nr_running(rq);
         }
+        ftrace_wake_up_new_task(p, rq->curr);
         check_preempt_curr(rq, p);
 #ifdef CONFIG_SMP
         if (p->sched_class->task_wake_up)
@@ -2783,6 +2785,7 @@ context_switch(struct rq *rq, struct task_struct *prev,
         struct mm_struct *mm, *oldmm;
 
         prepare_task_switch(rq, prev, next);
+        ftrace_ctx_switch(prev, next);
         mm = next->mm;
         oldmm = prev->active_mm;
         /*