linux-kernel - drivers/acpi/processor_thermal.c: avoid cpufreq_get

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Date:   Wed, 22 Dec 2021 20:14:11 +0100
From:   Manfred Spraul <manfred@...orfullife.com>
To:     LKML <linux-kernel@...r.kernel.org>, linux-acpi@...r.kernel.org,
        "Rafael J . Wysocki " <rafael@...nel.org>,
        Zhang Rui <rui.zhang@...el.com>, Len Brown <lenb@...nel.org>
Cc:     1vier1@....de, Manfred Spraul <manfred@...orfullife.com>
Subject: drivers/acpi/processor_thermal.c: avoid cpufreq_get_policy()

cpu_has_cpufreq() stores a 'struct cpufreq_policy' on the stack.
Unfortunately, with debugging options enabled, the structure can be
larger than 1024 bytes, which causes a compiler warning/error.

(actually observed: 1184 bytes).

Therefore: Switch to cpufreq_cpu_get().

Signed-off-by: Manfred Spraul <manfred@...orfullife.com>

---
 drivers/acpi/processor_thermal.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c
index a3d34e3f9f94..74210d63f62c 100644
--- a/drivers/acpi/processor_thermal.c
+++ b/drivers/acpi/processor_thermal.c
@@ -53,10 +53,19 @@ static int phys_package_first_cpu(int cpu)
 
 static int cpu_has_cpufreq(unsigned int cpu)
 {
-	struct cpufreq_policy policy;
-	if (!acpi_processor_cpufreq_init || cpufreq_get_policy(&policy, cpu))
+	struct cpufreq_policy *policy;
+	int retval;
+
+	if (!acpi_processor_cpufreq_init)
 		return 0;
-	return 1;
+
+	retval = 0;
+	policy = cpufreq_cpu_get(cpu);
+	if (policy) {
+		cpufreq_cpu_put(policy);
+		retval = 1;
+	}
+	return retval;
 }
 
 static int cpufreq_get_max_state(unsigned int cpu)
-- 
2.33.1