diff mbox series

memory: samsung: exynos5422-dmc: Additional locking for 'curr_rate'

Message ID 20200811101727.3976-1-lukasz.luba@arm.com (mailing list archive)
State Accepted
Headers show
Series memory: samsung: exynos5422-dmc: Additional locking for 'curr_rate' | expand

Commit Message

Lukasz Luba Aug. 11, 2020, 10:17 a.m. UTC
The 'curr_rate' is protected by local 'dmc->lock' in various places, but
not in a function exynos5_dmc_get_status(). The lock protects frequency
(and voltage) change process and the corresponding value stored in
'curr_rate'. Add the locking mechanism to protect the 'curr_rate' reading
also in the exynos5_dmc_get_status().

Suggested-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
---
 drivers/memory/samsung/exynos5422-dmc.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Krzysztof Kozlowski Aug. 17, 2020, 11:54 a.m. UTC | #1
On Tue, Aug 11, 2020 at 11:17:27AM +0100, Lukasz Luba wrote:
> The 'curr_rate' is protected by local 'dmc->lock' in various places, but
> not in a function exynos5_dmc_get_status(). The lock protects frequency
> (and voltage) change process and the corresponding value stored in
> 'curr_rate'. Add the locking mechanism to protect the 'curr_rate' reading
> also in the exynos5_dmc_get_status().
> 
> Suggested-by: Krzysztof Kozlowski <krzk@kernel.org>
> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
> ---
>  drivers/memory/samsung/exynos5422-dmc.c | 3 +++

Thanks, applied.

Best regards,
Krzysztof
Lukasz Luba Aug. 17, 2020, 12:28 p.m. UTC | #2
Hi Krzysztof,

On 8/17/20 12:54 PM, Krzysztof Kozlowski wrote:
> On Tue, Aug 11, 2020 at 11:17:27AM +0100, Lukasz Luba wrote:
>> The 'curr_rate' is protected by local 'dmc->lock' in various places, but
>> not in a function exynos5_dmc_get_status(). The lock protects frequency
>> (and voltage) change process and the corresponding value stored in
>> 'curr_rate'. Add the locking mechanism to protect the 'curr_rate' reading
>> also in the exynos5_dmc_get_status().
>>
>> Suggested-by: Krzysztof Kozlowski <krzk@kernel.org>
>> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
>> ---
>>   drivers/memory/samsung/exynos5422-dmc.c | 3 +++
> 
> Thanks, applied.
> 

Thank you for applying it.

Regards,
Lukasz
diff mbox series

Patch

diff --git a/drivers/memory/samsung/exynos5422-dmc.c b/drivers/memory/samsung/exynos5422-dmc.c
index b9c7956e5031..952bc61e68f4 100644
--- a/drivers/memory/samsung/exynos5422-dmc.c
+++ b/drivers/memory/samsung/exynos5422-dmc.c
@@ -908,7 +908,10 @@  static int exynos5_dmc_get_status(struct device *dev,
 	int ret;
 
 	if (dmc->in_irq_mode) {
+		mutex_lock(&dmc->lock);
 		stat->current_frequency = dmc->curr_rate;
+		mutex_unlock(&dmc->lock);
+
 		stat->busy_time = dmc->load;
 		stat->total_time = dmc->total;
 	} else {