Commit 4de9ff76 authored Jan 13, 2026 by Peter Zijlstra

sched/deadline: Avoid double update_rq_clock()



When setup_new_dl_entity() is called from enqueue_task_dl() ->
enqueue_dl_entity(), the rq-clock should already be updated, and
calling update_rq_clock() again is not right.

Move the update_rq_clock() to the one other caller of
setup_new_dl_entity(): sched_init_dl_server().

Fixes: 9f239df5 ("sched/deadline: Initialize dl_servers after SMP")
Reported-by: Pierre Gondois <pierre.gondois@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Pierre Gondois <pierre.gondois@arm.com>
Link: https://patch.msgid.link/20260113115622.GA831285@noisy.programming.kicks-ass.net

parent 375410bb

kernel/sched/deadline.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -752,8 +752,6 @@ static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se)
		struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
		struct rq *rq = rq_of_dl_rq(dl_rq);

		update_rq_clock(rq);

		WARN_ON(is_dl_boosted(dl_se));
		WARN_ON(dl_time_before(rq_clock(rq), dl_se->deadline));

		@@ -1839,6 +1837,7 @@ void sched_init_dl_servers(void)
		rq = cpu_rq(cpu);

		guard(rq_lock_irq)(rq);
		update_rq_clock(rq);

		dl_se = &rq->fair_server;