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From: Lukasz Luba <lukasz.luba@arm.com>
To: oss-self-reviewed-patches@listhost.cambridge.arm.com,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org,
	linux-samsung-soc@vger.kernel.org, krzk@kernel.org
Cc: kgene@kernel.org, b.zolnierkie@samsung.com, lukasz.luba@arm.com
Subject: [PATCH] memory: samsung: exynos5422-dmc: Additional locking for 'curr_rate'
Date: Tue, 11 Aug 2020 11:17:27 +0100	[thread overview]
Message-ID: <20200811101727.3976-1-lukasz.luba@arm.com> (raw)

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(+)

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 {
-- 
2.17.1


WARNING: multiple messages have this Message-ID (diff)
From: Lukasz Luba <lukasz.luba@arm.com>
To: oss-self-reviewed-patches@listhost.cambridge.arm.com,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-pm@vger.kernel.org,
	linux-samsung-soc@vger.kernel.org, krzk@kernel.org
Cc: kgene@kernel.org, lukasz.luba@arm.com, b.zolnierkie@samsung.com
Subject: [PATCH] memory: samsung: exynos5422-dmc: Additional locking for 'curr_rate'
Date: Tue, 11 Aug 2020 11:17:27 +0100	[thread overview]
Message-ID: <20200811101727.3976-1-lukasz.luba@arm.com> (raw)

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(+)

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 {
-- 
2.17.1


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             reply	other threads:[~2020-08-11 10:17 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-11 10:17 Lukasz Luba [this message]
2020-08-11 10:17 ` [PATCH] memory: samsung: exynos5422-dmc: Additional locking for 'curr_rate' Lukasz Luba
2020-08-17 11:54 ` Krzysztof Kozlowski
2020-08-17 11:54   ` Krzysztof Kozlowski
2020-08-17 12:28   ` Lukasz Luba
2020-08-17 12:28     ` Lukasz Luba
  -- strict thread matches above, loose matches on Subject: below --
2020-08-11 10:16 Lukasz Luba
2020-08-11 10:16 ` Lukasz Luba

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