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: Frederic 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: Paul E. McKenney <paulmck@kernel.org>
This commit is contained in:
Frederic Weisbecker 2022-02-16 16:42:06 +01:00 committed by Paul E. McKenney
parent 8d2aaa9b7c
commit 2eed973adc

View file

@ -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) {
rcutree_prepare_cpu(cpu);
rcu_cpu_starting(cpu);
rcutree_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);