The call of rcu_idle_enter() from within cpuidle_idle_call() was
removed in commit 1098582a0f6c ("sched,idle,rcu: Push rcu_idle deeper
into the idle path") which makes the comment out of place.

Signed-off-by: Christian Loehle <christian.loehle@arm.com>
---
 kernel/sched/idle.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 6135fbe83d68..3cc1a592d9a1 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -179,12 +179,6 @@ static void cpuidle_idle_call(void)
 		return;
 	}
 
-	/*
-	 * The RCU framework needs to be told that we are entering an idle
-	 * section, so no more rcu read side critical sections and one more
-	 * step to the grace period
-	 */
-
 	if (cpuidle_not_available(drv, dev)) {
 		tick_nohz_idle_stop_tick();
 
-- 
2.34.1

On 6/3/2024 5:30 PM, Christian Loehle wrote:
> The call of rcu_idle_enter() from within cpuidle_idle_call() was
> removed in commit 1098582a0f6c ("sched,idle,rcu: Push rcu_idle deeper
> into the idle path") which makes the comment out of place.
>
> Signed-off-by: Christian Loehle <christian.loehle@arm.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


> ---
>   kernel/sched/idle.c | 6 ------
>   1 file changed, 6 deletions(-)
>
> diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
> index 6135fbe83d68..3cc1a592d9a1 100644
> --- a/kernel/sched/idle.c
> +++ b/kernel/sched/idle.c
> @@ -179,12 +179,6 @@ static void cpuidle_idle_call(void)
>   		return;
>   	}
>   
> -	/*
> -	 * The RCU framework needs to be told that we are entering an idle
> -	 * section, so no more rcu read side critical sections and one more
> -	 * step to the grace period
> -	 */
> -
>   	if (cpuidle_not_available(drv, dev)) {
>   		tick_nohz_idle_stop_tick();
>

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     764d5fcc2a58d789629f6800451975fc93f25822
Gitweb:        https://git.kernel.org/tip/764d5fcc2a58d789629f6800451975fc93f25822
Author:        Christian Loehle <christian.loehle@arm.com>
AuthorDate:    Mon, 03 Jun 2024 16:30:39 +01:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Wed, 05 Jun 2024 15:52:35 +02:00

idle: Remove stale RCU comment

The call of rcu_idle_enter() from within cpuidle_idle_call() was
removed in commit 1098582a0f6c ("sched,idle,rcu: Push rcu_idle deeper
into the idle path") which makes the comment out of place.

Signed-off-by: Christian Loehle <christian.loehle@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/5b936388-47df-4050-9229-6617a6c2bba5@arm.com
---
 kernel/sched/idle.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 770e698..6e78d07 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -179,12 +179,6 @@ static void cpuidle_idle_call(void)
 		return;
 	}
 
-	/*
-	 * The RCU framework needs to be told that we are entering an idle
-	 * section, so no more RCU read side critical sections and one more
-	 * step to the grace period
-	 */
-
 	if (cpuidle_not_available(drv, dev)) {
 		tick_nohz_idle_stop_tick();