Re: [PATCH v1] cpufreq: Allow exit latency to exceed target residency

[Christian Loehle]

On 6/17/26 17:16, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> 
> Commit 76934e495cdc ("cpuidle: Add sanity check for exit latency and
> target residency") had added a check to prevent the exit latency of an
> idle state from exceeding its target residency that later was limited to
> printing a warning message in that case in commit 4bf944f3fcb6 ("cpuidle:
> Warn instead of bailing out if target residency check fails").
> 
> However, a thorough code inspection with that in mind leads to the
> conclusion that actually there are no assumptions in cpuidle regarding
> the relationship between the exit latency and target residency of a
> given idle state.  It is generally assumed that the idle states table
> provided by a cpuidle driver will be sorted by both the target residency
> and exit latency in ascending order, but that's a different matter.
> 
> Accordingly, drop the check in question along with the message printed
> when it triggers and the inaccurate comment preceding it.
> 
> Fixes: 4bf944f3fcb6 ("cpuidle: Warn instead of bailing out if target residency check fails")
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> ---
>  drivers/cpuidle/driver.c           |    8 --------
>  drivers/cpuidle/governors/ladder.c |    2 ++

ladder.c?

>  2 files changed, 2 insertions(+), 8 deletions(-)
> 
> --- a/drivers/cpuidle/driver.c
> +++ b/drivers/cpuidle/driver.c
> @@ -195,14 +195,6 @@ static void __cpuidle_driver_init(struct
>  			s->exit_latency_ns =  0;
>  		else
>  			s->exit_latency = div_u64(s->exit_latency_ns, NSEC_PER_USEC);
> -
> -		/*
> -		 * Warn if the exit latency of a CPU idle state exceeds its
> -		 * target residency which is assumed to never happen in cpuidle
> -		 * in multiple places.
> -		 */
> -		if (s->exit_latency_ns > s->target_residency_ns)
> -			pr_warn("Idle state %d target residency too low\n", i);
>  	}
>  }
>  
> 

Fine with me, but the title is cpufreq: instead of cpuidle.
If you'll fix it when applying:
Reviewed-by: Christian Loehle <christian.loehle@xxxxxxx>