[PATCH 15/36] cpuidle,cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}()

Peter Zijlstra
2022-06-08T14:50:41Z

All callers should still have RCU enabled.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
kernel/cpu_pm.c | 9 ---------
1 file changed, 9 deletions(-)

--- a/kernel/cpu_pm.c
+++ b/kernel/cpu_pm.c
@@ -30,16 +30,9 @@ static int cpu_pm_notify(enum cpu_pm_eve
{
int ret;

- /*
- * This introduces a RCU read critical section, which could be
- * disfunctional in cpu idle. Copy RCU_NONIDLE code to let RCU know
- * this.
- */
- rcu_irq_enter_irqson();
rcu_read_lock();
ret = raw_notifier_call_chain(&cpu_pm_notifier.chain, event, NULL);
rcu_read_unlock();
- rcu_irq_exit_irqson();

return notifier_to_errno(ret);
}
@@ -49,11 +42,9 @@ static int cpu_pm_notify_robust(enum cpu
unsigned long flags;
int ret;

- rcu_irq_enter_irqson();
raw_spin_lock_irqsave(&cpu_pm_notifier.lock, flags);
ret = raw_notifier_call_chain_robust(&cpu_pm_notifier.chain, event_up, event_down, NULL);
raw_spin_unlock_irqrestore(&cpu_pm_notifier.lock, flags);
- rcu_irq_exit_irqson();

return notifier_to_errno(ret);
}