On Mon, 2025-08-11 at 10:40 +0200, Nam Cao wrote: > Add trace points into enqueue_task() and dequeue_task(). They are > useful to implement RV monitor which validates RT scheduling. > > Signed-off-by: Nam Cao <[email protected]> > ---
Peter, Ingo, this patch adds new tracepoints in the scheduler do agree with the change, can we get an Ack? Thanks, Gabriele > Cc: Ingo Molnar <[email protected]> > Cc: Peter Zijlstra <[email protected]> > Cc: Juri Lelli <[email protected]> > Cc: Vincent Guittot <[email protected]> > Cc: Dietmar Eggemann <[email protected]> > Cc: Ben Segall <[email protected]> > Cc: Mel Gorman <[email protected]> > Cc: Valentin Schneider <[email protected]> > Cc: K Prateek Nayak <[email protected]> > --- > v3: fix up build issue on !SMP > v2: Move the tracepoints to cover all task enqueue/dequeue, not just > RT > --- > include/trace/events/sched.h | 13 +++++++++++++ > kernel/sched/core.c | 8 +++++++- > 2 files changed, 20 insertions(+), 1 deletion(-) > > diff --git a/include/trace/events/sched.h > b/include/trace/events/sched.h > index 7b2645b50e78..696d22af5a98 100644 > --- a/include/trace/events/sched.h > +++ b/include/trace/events/sched.h > @@ -896,6 +896,19 @@ DECLARE_TRACE(sched_set_need_resched, > TP_PROTO(struct task_struct *tsk, int cpu, int tif), > TP_ARGS(tsk, cpu, tif)); > > +/* > + * The two trace points below may not work as expected for fair > tasks due > + * to delayed dequeue. See: > + * > https://lore.kernel.org/lkml/[email protected]/ > + */ > +DECLARE_TRACE(enqueue_task, > + TP_PROTO(int cpu, struct task_struct *task), > + TP_ARGS(cpu, task)); > + > +DECLARE_TRACE(dequeue_task, > + TP_PROTO(int cpu, struct task_struct *task), > + TP_ARGS(cpu, task)); > + > #endif /* _TRACE_SCHED_H */ > > /* This part must be outside protection */ > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index be00629f0ba4..6367799aa023 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -2077,6 +2077,8 @@ unsigned long get_wchan(struct task_struct *p) > > void enqueue_task(struct rq *rq, struct task_struct *p, int flags) > { > + trace_enqueue_task_tp(cpu_of(rq), p); > + > if (!(flags & ENQUEUE_NOCLOCK)) > update_rq_clock(rq); > > @@ -2119,7 +2121,11 @@ inline bool dequeue_task(struct rq *rq, struct > task_struct *p, int flags) > * and mark the task ->sched_delayed. > */ > uclamp_rq_dec(rq, p); > - return p->sched_class->dequeue_task(rq, p, flags); > + if (p->sched_class->dequeue_task(rq, p, flags)) { > + trace_dequeue_task_tp(cpu_of(rq), p); > + return true; > + } > + return false; > } > > void activate_task(struct rq *rq, struct task_struct *p, int flags)
