Re: [RFC 1/6] sched: Add nice value change notifier

On Thu, Sep 30, 2021 at 06:15:47PM +0100, Tvrtko Ursulin wrote:

void set_user_nice(struct task_struct *p, long nice) { bool queued, running;

• int old_prio;

• int old_prio, ret; struct rq_flags rf; struct rq *rq;

@@ -6913,6 +6945,9 @@ void set_user_nice(struct task_struct *p, long nice) */ p->sched_class->prio_changed(rq, p, old_prio);

• ret = atomic_notifier_call_chain(&user_nice_notifier_list, nice, p);
• WARN_ON_ONCE(ret != NOTIFY_DONE);

out_unlock: task_rq_unlock(rq, p, &rf); }

No, we're not going to call out to exported, and potentially unbounded, functions under scheduler locks.