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Subject[PATCH] Cpufreq: Acquire read lock in the cpufreq_policy_restore() rather than write lock
Date
From: Lan Tianyu <tianyu.lan@intel.com>

In the cpufreq_policy_restore(), policy before system suspend is read from
from percpu's cpufreq_cpu_data_fallback. It's read operation rather than
write operation. So convert write lock to read lock

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
---
drivers/cpufreq/cpufreq.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 81ceea6..b762f9b 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -912,11 +912,11 @@ static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu)
struct cpufreq_policy *policy;
unsigned long flags;

- write_lock_irqsave(&cpufreq_driver_lock, flags);
+ read_lock_irqsave(&cpufreq_driver_lock, flags);

policy = per_cpu(cpufreq_cpu_data_fallback, cpu);

- write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+ read_unlock_irqrestore(&cpufreq_driver_lock, flags);

return policy;
}
--
1.8.4.rc0.1.g8f6a3e5.dirty


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