2026-01-22T15:56:08Z Gabriele Monaco <[email protected]>: > From: Nam Cao <[email protected]> > > Add trace points into enqueue_task() and dequeue_task(). >
Peter, can I have your Ack on this? (Apologies for the spam, I sent it as HTML by mistake) Thanks, Gabriele > Suggested-by: Peter Zijlstra <[email protected]> > Signed-off-by: Nam Cao <[email protected]> > Reviewed-by: K Prateek Nayak <[email protected]> > Signed-off-by: Gabriele Monaco <[email protected]> > --- > > Notes: > V5: > * Do not fire enqueue tracepoint for delayed enqueues > > include/trace/events/sched.h | 13 +++++++++++++ > kernel/sched/core.c | 10 +++++++++- > kernel/sched/sched.h | 2 ++ > 3 files changed, 24 insertions(+), 1 deletion(-) > > diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h > index 366b2e8ec40c..f4e1d3554e3e 100644 > --- a/include/trace/events/sched.h > +++ b/include/trace/events/sched.h > @@ -912,6 +912,19 @@ DECLARE_TRACE(sched_dl_server_stop, > TP_PROTO(struct sched_dl_entity *dl_se, int cpu), > TP_ARGS(dl_se, cpu)); > > +/* > + * 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(sched_enqueue, > + TP_PROTO(struct task_struct *tsk, int cpu), > + TP_ARGS(tsk, cpu)); > + > +DECLARE_TRACE(sched_dequeue, > + TP_PROTO(struct task_struct *tsk, int cpu), > + TP_ARGS(tsk, cpu)); > + > #endif /* _TRACE_SCHED_H */ > > /* This part must be outside protection */ > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index f6293fa02fb7..c885d7885172 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -2087,6 +2087,9 @@ unsigned long get_wchan(struct task_struct *p) > > void enqueue_task(struct rq *rq, struct task_struct *p, int flags) > { > + if (trace_sched_enqueue_tp_enabled() && !(flags & ENQUEUE_DELAYED)) > + trace_sched_enqueue_tp(p, rq->cpu); > + > if (!(flags & ENQUEUE_NOCLOCK)) > update_rq_clock(rq); > > @@ -2114,6 +2117,8 @@ void enqueue_task(struct rq *rq, struct task_struct *p, > int flags) > */ > inline bool dequeue_task(struct rq *rq, struct task_struct *p, int flags) > { > + int ret; > + > if (sched_core_enabled(rq)) > sched_core_dequeue(rq, p, flags); > > @@ -2131,7 +2136,10 @@ inline bool dequeue_task(struct rq *rq, struct > task_struct *p, int flags) > */ > uclamp_rq_dec(rq, p); > rq->queue_mask |= p->sched_class->queue_mask; > - return p->sched_class->dequeue_task(rq, p, flags); > + ret = p->sched_class->dequeue_task(rq, p, flags); > + if (trace_sched_dequeue_tp_enabled() && !(flags & DEQUEUE_SLEEP)) > + trace_sched_dequeue_tp(p, rq->cpu); > + return ret; > } > > void activate_task(struct rq *rq, struct task_struct *p, int flags) > diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h > index e885a935b716..8465472b40fa 100644 > --- a/kernel/sched/sched.h > +++ b/kernel/sched/sched.h > @@ -2918,6 +2918,8 @@ static inline void sub_nr_running(struct rq *rq, > unsigned count) > > static inline void __block_task(struct rq *rq, struct task_struct *p) > { > + trace_sched_dequeue_tp(p, rq->cpu); > + > if (p->sched_contributes_to_load) > rq->nr_uninterruptible++; > > -- > 2.52.0
