On Wed, Sep 3, 2025 at 3:18 PM Zihuan Zhang <zhangzih...@kylinos.cn> wrote:
>
> Replace the manual cpufreq_cpu_put() with __free(put_cpufreq_policy)
> annotation for policy references. This reduces the risk of reference
> counting mistakes and aligns the code with the latest kernel style.
>
> No functional change intended.
>
> Signed-off-by: Zihuan Zhang <zhangzih...@kylinos.cn>
> ---
> drivers/powercap/dtpm_cpu.c | 30 +++++++++++-------------------
> 1 file changed, 11 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c
> index 99390ec1481f..f76594185fa2 100644
> --- a/drivers/powercap/dtpm_cpu.c
> +++ b/drivers/powercap/dtpm_cpu.c
> @@ -144,19 +144,17 @@ static int update_pd_power_uw(struct dtpm *dtpm)
> static void pd_release(struct dtpm *dtpm)
> {
> struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm);
> - struct cpufreq_policy *policy;
>
> if (freq_qos_request_active(&dtpm_cpu->qos_req))
> freq_qos_remove_request(&dtpm_cpu->qos_req);
>
> - policy = cpufreq_cpu_get(dtpm_cpu->cpu);
> - if (policy) {
> + struct cpufreq_policy *policy __free(put_cpufreq_policy) =
> + cpufreq_cpu_get(dtpm_cpu->cpu);
> +
> + if (policy)
> for_each_cpu(dtpm_cpu->cpu, policy->related_cpus)
> per_cpu(dtpm_per_cpu, dtpm_cpu->cpu) = NULL;
>
> - cpufreq_cpu_put(policy);
> - }
> -
> kfree(dtpm_cpu);
> }
>
> @@ -192,7 +190,6 @@ static int cpuhp_dtpm_cpu_online(unsigned int cpu)
> static int __dtpm_cpu_setup(int cpu, struct dtpm *parent)
> {
> struct dtpm_cpu *dtpm_cpu;
> - struct cpufreq_policy *policy;
> struct em_perf_state *table;
> struct em_perf_domain *pd;
> char name[CPUFREQ_NAME_LEN];
> @@ -202,21 +199,19 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm
> *parent)
> if (dtpm_cpu)
> return 0;
>
> - policy = cpufreq_cpu_get(cpu);
> + struct cpufreq_policy *policy __free(put_cpufreq_policy) =
> + cpufreq_cpu_get(cpu);
> +
> if (!policy)
> return 0;
>
> pd = em_cpu_get(cpu);
> - if (!pd || em_is_artificial(pd)) {
> - ret = -EINVAL;
> - goto release_policy;
> - }
> + if (!pd || em_is_artificial(pd))
> + return -EINVAL;
>
> dtpm_cpu = kzalloc(sizeof(*dtpm_cpu), GFP_KERNEL);
> - if (!dtpm_cpu) {
> - ret = -ENOMEM;
> - goto release_policy;
> - }
> + if (!dtpm_cpu)
> + return -ENOMEM;
>
> dtpm_init(&dtpm_cpu->dtpm, &dtpm_ops);
> dtpm_cpu->cpu = cpu;
> @@ -239,7 +234,6 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent)
> if (ret < 0)
> goto out_dtpm_unregister;
So this change kind of goes against another recommendation given in cleanup.h:
* Lastly, given that the benefit of cleanup helpers is removal of
* "goto", and that the "goto" statement can jump between scopes, the
* expectation is that usage of "goto" and cleanup helpers is never
* mixed in the same function. I.e. for a given routine, convert all
* resources that need a "goto" cleanup to scope-based cleanup, or
* convert none of them.
>
> - cpufreq_cpu_put(policy);
> return 0;
>
> out_dtpm_unregister:
> @@ -251,8 +245,6 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent)
> per_cpu(dtpm_per_cpu, cpu) = NULL;
> kfree(dtpm_cpu);
>
> -release_policy:
> - cpufreq_cpu_put(policy);
> return ret;
> }
>
> --
