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Ack! I didn't know this was the config that printed the condition for the warn on. I'll make sure to enable it henceforth. [..snip..] >> Since the dequeue on a deadline task can push its deadline, stash the >> task prio towards the end of sched_change_begin(). >> >> The modification to priority within the sched_change guard's scope will >> still be considered as sched_change_end() will supply the priority >> stashed at the end of constructor's execution as the old priority to >> sched_class->prio_changed(). >> > > Would not something like so make more sense? > > --- > diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c > index 80c9559a3e30..60e0c25aae78 100644 > --- a/kernel/sched/deadline.c > +++ b/kernel/sched/deadline.c > @@ -3306,6 +3306,8 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p) > > static u64 get_prio_dl(struct rq *rq, struct task_struct *p) > { > + if (task_current_donor(rq, p)) > + update_curr_dl(rq); > return p->dl.deadline; > } > Yup this makes sense too! Feel free to add a small note like: Catch up the deadline before returning it from get_prio() for the current donor. This ensures the sched_change guard caches the latest value and doesn't mistake the subsequent dequeue to have changed the task's priority. and include: Reviewed-and-tested-by: K Prateek Nayak -- Thanks and Regards, Prateek