From: Zihuan Zhang <zhangzihuan@kylinos.cn>

During S3/S4 suspend and resume, cpufreq policies are not freed or
recreated; the freq_table and policy structure remain intact. However,
set_freq_table_sorted() currently resets policy->freq_table_sorted to
UNSORTED unconditionally, which is unnecessary since the table order
does not change across suspend/resume.

This patch adds a check to skip validation if policy->freq_table_sorted
is already ASCENDING or DESCENDING. This avoids unnecessary traversal
of the frequency table on S3/S4 resume or repeated online events,
reducing overhead while preserving correctness.

Signed-off-by: Zihuan Zhang <zhangzihuan@kylinos.cn>
---
 drivers/cpufreq/cpufreq.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 852e024facc3..4a27f6cb07d3 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1421,9 +1421,12 @@ static int cpufreq_policy_online(struct cpufreq_policy *policy,
 		 * If there is a problem with its frequency table, take it
 		 * offline and drop it.
 		 */
-		ret = cpufreq_table_validate_and_sort(policy);
-		if (ret)
-			goto out_offline_policy;
+		if (policy->freq_table_sorted != CPUFREQ_TABLE_SORTED_ASCENDING &&
+		    policy->freq_table_sorted != CPUFREQ_TABLE_SORTED_DESCENDING) {
+			ret = cpufreq_table_validate_and_sort(policy);
+			if (ret)
+				goto out_offline_policy;
+		}
 
 		/* related_cpus should at least include policy->cpus. */
 		cpumask_copy(policy->related_cpus, policy->cpus);
-- 
2.25.1

On Sat, Oct 11, 2025 at 9:24 AM zzhwaxy <zhangzihuan@kylinos.cn> wrote:
>
> From: Zihuan Zhang <zhangzihuan@kylinos.cn>
>
> During S3/S4 suspend and resume, cpufreq policies are not freed or
> recreated; the freq_table and policy structure remain intact. However,
> set_freq_table_sorted() currently resets policy->freq_table_sorted to
> UNSORTED unconditionally, which is unnecessary since the table order
> does not change across suspend/resume.
>
> This patch adds a check to skip validation if policy->freq_table_sorted
> is already ASCENDING or DESCENDING. This avoids unnecessary traversal
> of the frequency table on S3/S4 resume or repeated online events,
> reducing overhead while preserving correctness.
>
> Signed-off-by: Zihuan Zhang <zhangzihuan@kylinos.cn>
> ---
>  drivers/cpufreq/cpufreq.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 852e024facc3..4a27f6cb07d3 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -1421,9 +1421,12 @@ static int cpufreq_policy_online(struct cpufreq_policy *policy,
>                  * If there is a problem with its frequency table, take it
>                  * offline and drop it.
>                  */
> -               ret = cpufreq_table_validate_and_sort(policy);
> -               if (ret)
> -                       goto out_offline_policy;
> +               if (policy->freq_table_sorted != CPUFREQ_TABLE_SORTED_ASCENDING &&
> +                   policy->freq_table_sorted != CPUFREQ_TABLE_SORTED_DESCENDING) {
> +                       ret = cpufreq_table_validate_and_sort(policy);
> +                       if (ret)
> +                               goto out_offline_policy;
> +               }
>
>                 /* related_cpus should at least include policy->cpus. */
>                 cpumask_copy(policy->related_cpus, policy->cpus);
> --

Applied as 6.19 material, thanks!