linux-kernel - [PATCH v3 09/12] powercap: dtpm_cpu: Use scope-based cleanup helper

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Message-Id: <20250901085748.36795-10-zhangzihuan@kylinos.cn>
Date: Mon,  1 Sep 2025 16:57:45 +0800
From: Zihuan Zhang <zhangzihuan@...inos.cn>
To: "Rafael J . wysocki" <rafael@...nel.org>,
	Viresh Kumar <viresh.kumar@...aro.org>,
	Catalin Marinas <catalin.marinas@....com>,
	Will Deacon <will@...nel.org>,
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Cc: Ben Horgan <ben.horgan@....com>,
	zhenglifeng <zhenglifeng1@...wei.com>,
	Zhang Rui <rui.zhang@...el.com>,
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	Sumit Gupta <sumitg@...dia.com>,
	Prasanna Kumar T S M <ptsm@...ux.microsoft.com>,
	Sudeep Holla <sudeep.holla@....com>,
	Yicong Yang <yangyicong@...ilicon.com>,
	linux-pm@...r.kernel.org,
	linux-acpi@...r.kernel.org,
	linuxppc-dev@...ts.ozlabs.org,
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	linux-kernel@...r.kernel.org,
	Zihuan Zhang <zhangzihuan@...inos.cn>
Subject: [PATCH v3 09/12] powercap: dtpm_cpu: Use scope-based cleanup helper

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 <zhangzihuan@...inos.cn>
---
 drivers/powercap/dtpm_cpu.c | 26 +++++++-------------------
 1 file changed, 7 insertions(+), 19 deletions(-)

diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c
index 99390ec1481f..5e18438782f8 100644
--- a/drivers/powercap/dtpm_cpu.c
+++ b/drivers/powercap/dtpm_cpu.c
@@ -144,19 +144,15 @@ 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;
+	struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(dtpm_cpu->cpu);
 
 	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) {
+	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 +188,7 @@ 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 cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpu);
 	struct em_perf_state *table;
 	struct em_perf_domain *pd;
 	char name[CPUFREQ_NAME_LEN];
@@ -202,21 +198,16 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent)
 	if (dtpm_cpu)
 		return 0;
 
-	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 +230,6 @@ static int __dtpm_cpu_setup(int cpu, struct dtpm *parent)
 	if (ret < 0)
 		goto out_dtpm_unregister;
 
-	cpufreq_cpu_put(policy);
 	return 0;
 
 out_dtpm_unregister:
@@ -251,8 +241,6 @@ 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;
 }
 
-- 
2.25.1