linux-kernel - [PATCH v1 06/10] cpufreq: Use locking guard and __free() in cpufreq_update

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Message-ID: <22654186.EfDdHjke4D@rjwysocki.net>
Date: Fri, 28 Mar 2025 21:44:50 +0100
From: "Rafael J. Wysocki" <rjw@...ysocki.net>
To: Linux PM <linux-pm@...r.kernel.org>
Cc: LKML <linux-kernel@...r.kernel.org>,
 Viresh Kumar <viresh.kumar@...aro.org>,
 Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
 Mario Limonciello <mario.limonciello@....com>,
 Sudeep Holla <sudeep.holla@....com>
Subject:
 [PATCH v1 06/10] cpufreq: Use locking guard and __free() in
 cpufreq_update_policy()

From: Rafael J. Wysocki <rafael.j.wysocki@...el.com>

Instead of using cpufreq_cpu_acquire() and cpufreq_cpu_release() in
cpufreq_update_policy(), which is the last user of these functions,
make it use __free() for policy reference counting cleanup and the
"write" locking guard for policy locking.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
---
 drivers/cpufreq/cpufreq.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2752,23 +2752,23 @@
  */
 void cpufreq_update_policy(unsigned int cpu)
 {
-	struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu);
+	struct cpufreq_policy *policy __free(put_cpufreq_policy);

+	policy = cpufreq_cpu_get(cpu);
 	if (!policy)
 		return;

+	guard(cpufreq_policy_write)(policy);
+
 	/*
 	 * BIOS might change freq behind our back
 	 * -> ask driver for current freq and notify governors about a change
 	 */
 	if (cpufreq_driver->get && has_target() &&
 	    (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false))))
-		goto unlock;
+		return;

 	refresh_frequency_limits(policy);
-
-unlock:
-	cpufreq_cpu_release(policy);
 }
 EXPORT_SYMBOL(cpufreq_update_policy);