diff mbox series

[v2,14/44] cpuidle,cpu_pm: Remove RCU fiddling from cpu_pm_{enter,exit}()

Message ID 20220919101521.274051658@infradead.org
State Superseded
Headers show
Series cpuidle,rcu: Clean up the mess | expand

Commit Message

Peter Zijlstra Sept. 19, 2022, 9:59 a.m. UTC 
All callers should still have RCU enabled.

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

Comments

Ulf Hansson Oct. 4, 2022, 11:04 a.m. UTC | #1 
On Mon, 19 Sept 2022 at 12:17, Peter Zijlstra <peterz@infradead.org> wrote:
>
> All callers should still have RCU enabled.
>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> Acked-by: Mark Rutland <mark.rutland@arm.com>

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>

Kind regards
Uffe

> ---
>  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.
> -        */
> -       ct_irq_enter_irqson();
>         rcu_read_lock();
>         ret = raw_notifier_call_chain(&cpu_pm_notifier.chain, event, NULL);
>         rcu_read_unlock();
> -       ct_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;
>
> -       ct_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);
> -       ct_irq_exit_irqson();
>
>         return notifier_to_errno(ret);
>  }
>
>
diff mbox series

Patch

--- 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.
-	 */
-	ct_irq_enter_irqson();
 	rcu_read_lock();
 	ret = raw_notifier_call_chain(&cpu_pm_notifier.chain, event, NULL);
 	rcu_read_unlock();
-	ct_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;
 
-	ct_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);
-	ct_irq_exit_irqson();
 
 	return notifier_to_errno(ret);
 }