Patch "cpufreq/amd-pstate: convert mutex use to guard()" has been added to the 6.12-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    cpufreq/amd-pstate: convert mutex use to guard()

to the 6.12-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     cpufreq-amd-pstate-convert-mutex-use-to-guard.patch
and it can be found in the queue-6.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit ea16a7ceb11c3ba3d1179b32d4abce18d3272a18
Author: Mario Limonciello <mario.limonciello@xxxxxxx>
Date:   Mon Dec 9 12:52:37 2024 -0600

    cpufreq/amd-pstate: convert mutex use to guard()
    
    [ Upstream commit 6c093d5a5b73ec1caf1e706510ae6031af2f9d43 ]
    
    Using scoped guard declaration will unlock mutexes automatically.
    
    Reviewed-by: Gautham R. Shenoy <gautham.shenoy@xxxxxxx>
    Link: https://lore.kernel.org/r/20241209185248.16301-5-mario.limonciello@xxxxxxx
    Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
    Stable-dep-of: 3ace20038e19 ("cpufreq/amd-pstate: Fix cpufreq_policy ref counting")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 145a48fc49034..33777f5ab7d16 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -696,12 +696,12 @@ static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state)
 		pr_err("Boost mode is not supported by this processor or SBIOS\n");
 		return -EOPNOTSUPP;
 	}
-	mutex_lock(&amd_pstate_driver_lock);
+	guard(mutex)(&amd_pstate_driver_lock);
+
 	ret = amd_pstate_cpu_boost_update(policy, state);
 	WRITE_ONCE(cpudata->boost_state, !ret ? state : false);
 	policy->boost_enabled = !ret ? state : false;
 	refresh_frequency_limits(policy);
-	mutex_unlock(&amd_pstate_driver_lock);
 
 	return ret;
 }
@@ -792,7 +792,8 @@ static void amd_pstate_update_limits(unsigned int cpu)
 	if (!amd_pstate_prefcore)
 		return;
 
-	mutex_lock(&amd_pstate_driver_lock);
+	guard(mutex)(&amd_pstate_driver_lock);
+
 	ret = amd_get_highest_perf(cpu, &cur_high);
 	if (ret)
 		goto free_cpufreq_put;
@@ -812,7 +813,6 @@ static void amd_pstate_update_limits(unsigned int cpu)
 	if (!highest_perf_changed)
 		cpufreq_update_policy(cpu);
 
-	mutex_unlock(&amd_pstate_driver_lock);
 }
 
 /*
@@ -1145,11 +1145,11 @@ static ssize_t store_energy_performance_preference(
 	if (ret < 0)
 		return -EINVAL;
 
-	mutex_lock(&amd_pstate_limits_lock);
+	guard(mutex)(&amd_pstate_limits_lock);
+
 	ret = amd_pstate_set_energy_pref_index(cpudata, ret);
-	mutex_unlock(&amd_pstate_limits_lock);
 
-	return ret ?: count;
+	return ret ? ret : count;
 }
 
 static ssize_t show_energy_performance_preference(
@@ -1297,13 +1297,10 @@ EXPORT_SYMBOL_GPL(amd_pstate_update_status);
 static ssize_t status_show(struct device *dev,
 			   struct device_attribute *attr, char *buf)
 {
-	ssize_t ret;
 
-	mutex_lock(&amd_pstate_driver_lock);
-	ret = amd_pstate_show_status(buf);
-	mutex_unlock(&amd_pstate_driver_lock);
+	guard(mutex)(&amd_pstate_driver_lock);
 
-	return ret;
+	return amd_pstate_show_status(buf);
 }
 
 static ssize_t status_store(struct device *a, struct device_attribute *b,
@@ -1312,9 +1309,8 @@ static ssize_t status_store(struct device *a, struct device_attribute *b,
 	char *p = memchr(buf, '\n', count);
 	int ret;
 
-	mutex_lock(&amd_pstate_driver_lock);
+	guard(mutex)(&amd_pstate_driver_lock);
 	ret = amd_pstate_update_status(buf, p ? p - buf : count);
-	mutex_unlock(&amd_pstate_driver_lock);
 
 	return ret < 0 ? ret : count;
 }
@@ -1614,13 +1610,11 @@ static int amd_pstate_epp_cpu_offline(struct cpufreq_policy *policy)
 
 	min_perf = READ_ONCE(cpudata->lowest_perf);
 
-	mutex_lock(&amd_pstate_limits_lock);
+	guard(mutex)(&amd_pstate_limits_lock);
 
 	amd_pstate_update_perf(cpudata, min_perf, 0, min_perf, false);
 	amd_pstate_set_epp(cpudata, AMD_CPPC_EPP_BALANCE_POWERSAVE);
 
-	mutex_unlock(&amd_pstate_limits_lock);
-
 	return 0;
 }
 
@@ -1656,13 +1650,11 @@ static int amd_pstate_epp_resume(struct cpufreq_policy *policy)
 	struct amd_cpudata *cpudata = policy->driver_data;
 
 	if (cpudata->suspended) {
-		mutex_lock(&amd_pstate_limits_lock);
+		guard(mutex)(&amd_pstate_limits_lock);
 
 		/* enable amd pstate from suspend state*/
 		amd_pstate_epp_reenable(cpudata);
 
-		mutex_unlock(&amd_pstate_limits_lock);
-
 		cpudata->suspended = false;
 	}