[PATCH v2 2/2] cpufreq: Serialize global boost updates

[Christian Loehle]

Serialize concurrent global boost sysfs writes with a mutex.

Fixes: 6f19efc0a1ca ("cpufreq: Add boost frequency support in core")
Signed-off-by: Christian Loehle <christian.loehle@xxxxxxx>
Reviewed-by: Pengjie Zhang <zhangpengjie2@xxxxxxxxxx>
---
 drivers/cpufreq/cpufreq.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 23a77f5524df..d95c849f79c5 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2810,6 +2810,8 @@ int cpufreq_boost_set_sw(struct cpufreq_policy *policy, int state)
 }
 EXPORT_SYMBOL_GPL(cpufreq_boost_set_sw);
 
+static DEFINE_MUTEX(cpufreq_boost_mutex);
+
 static int cpufreq_boost_trigger_state(int state)
 {
 	struct cpufreq_policy *policy;
@@ -2817,6 +2819,8 @@ static int cpufreq_boost_trigger_state(int state)
 	bool boost_enabled;
 	int ret = -EOPNOTSUPP;
 
+	guard(mutex)(&cpufreq_boost_mutex);
+
 	/*
 	 * Don't compare 'cpufreq_driver->boost_enabled' with 'state' here to
 	 * make sure all policies are in sync with global boost flag.
-- 
2.34.1