Commit a03fee33 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

sched/fair: Remove superfluous rcu_read_lock() 



With fair switched to rcu_dereference_all() validation, having IRQ or
preemption disabled is sufficient, remove the rcu_read_lock()
clutter.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://patch.msgid.link/20251127154725.647502625@infradead.org
parent 71fedc41

kernel/sched/fair.c

+1 −8
Original line number Diff line number Diff line
@@ -12856,21 +12856,16 @@ static int sched_balance_newidle(struct rq *this_rq, struct rq_flags *rf) 
	 */

	rq_unpin_lock(this_rq, rf);



	rcu_read_lock();

	sd = rcu_dereference_sched_domain(this_rq->sd);

	if (!sd) {

		rcu_read_unlock();

	if (!sd)

		goto out;

	}



	if (!get_rd_overloaded(this_rq->rd) ||

	    this_rq->avg_idle < sd->max_newidle_lb_cost) {



		update_next_balance(sd, &next_balance);

		rcu_read_unlock();

		goto out;

	}

	rcu_read_unlock();



	/*

	 * Include sched_balance_update_blocked_averages() in the cost
@@ -12883,7 +12878,6 @@ static int sched_balance_newidle(struct rq *this_rq, struct rq_flags *rf) 
	rq_modified_clear(this_rq);

	raw_spin_rq_unlock(this_rq);



	rcu_read_lock();

	for_each_domain(this_cpu, sd) {

		u64 domain_cost;
@@ -12933,7 +12927,6 @@ static int sched_balance_newidle(struct rq *this_rq, struct rq_flags *rf) 
		if (pulled_task || !continue_balancing)

			break;

	}

	rcu_read_unlock();



	raw_spin_rq_lock(this_rq);