Commit 2eed973a authored by Frederic Weisbecker's avatar Frederic Weisbecker Committed by Paul E. McKenney
Browse files

rcu: Assume rcu_init() is called before smp 



The rcu_init() function is called way before SMP is initialized and
therefore only the boot CPU should be online at this stage.

Simplify the boot per-cpu initialization accordingly.

Signed-off-by: default avatarFrederic Weisbecker <frederic@kernel.org>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Uladzislau Rezki <uladzislau.rezki@sony.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 8d2aaa9b

kernel/rcu/tree.c

+5 −6
Original line number Diff line number Diff line
@@ -4782,7 +4782,7 @@ static void __init kfree_rcu_batch_init(void) 


void __init rcu_init(void)

{

	int cpu;

	int cpu = smp_processor_id();



	rcu_early_boot_tests();
@@ -4802,11 +4802,10 @@ void __init rcu_init(void) 
	 * or the scheduler are operational.

	 */

	pm_notifier(rcu_pm_notify, 0);

	for_each_online_cpu(cpu) {

	WARN_ON(num_online_cpus() > 1); // Only one CPU this early in boot.

	rcutree_prepare_cpu(cpu);

	rcu_cpu_starting(cpu);

	rcutree_online_cpu(cpu);

	}



	/* Create workqueue for Tree SRCU and for expedited GPs. */

	rcu_gp_wq = alloc_workqueue("rcu_gp", WQ_MEM_RECLAIM, 0);