Commit bd3bff9e authored by Ingo Molnar's avatar Ingo Molnar Committed by Thomas Gleixner
Browse files

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: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 75d3bce2

include/linux/sched.h

+26 −0
Original line number Diff line number Diff line
@@ -2117,6 +2117,32 @@ static inline void arch_pick_mmap_layout(struct mm_struct *mm) 
}

#endif



#ifdef CONFIG_CONTEXT_SWITCH_TRACER

extern void

ftrace_ctx_switch(struct task_struct *prev, struct task_struct *next);

#else

static inline void

ftrace_ctx_switch(struct task_struct *prev, struct task_struct *next)

{

}

#endif



#ifdef CONFIG_SCHED_TRACER

extern void

ftrace_wake_up_task(struct task_struct *wakee, struct task_struct *curr);

extern void

ftrace_wake_up_new_task(struct task_struct *wakee, struct task_struct *curr);

#else

static inline void

ftrace_wake_up_task(struct task_struct *wakee, struct task_struct *curr)

{

}

static inline void

ftrace_wake_up_new_task(struct task_struct *wakee, struct task_struct *curr)

{

}

#endif



extern long sched_setaffinity(pid_t pid, const cpumask_t *new_mask);

extern long sched_getaffinity(pid_t pid, cpumask_t *mask);

kernel/sched.c

+3 −0
Original line number Diff line number Diff line
@@ -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;

	/*