From: Cho KyongHo <pullip.cho@xxxxxxxxxxx>
Since acquiring read_lock is not more frequent than write_lock, it is
not beneficial to use rwlock, this commit changes rwlock to spinlock.
Reviewed-by: Grant Grundler <grundler@xxxxxxxxxxxx>
Signed-off-by: Cho KyongHo <pullip.cho@xxxxxxxxxxx>
Signed-off-by: Shaik Ameer Basha <shaik.ameer@xxxxxxxxxxx>
---
drivers/iommu/exynos-iommu.c | 27 ++++++++++++++-------------
1 file changed, 14 insertions(+), 13 deletions(-)
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index c1be65f..d89ad5f 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -164,7 +164,7 @@ struct sysmmu_drvdata {
struct clk *clk;
struct clk *clk_master;
int activations;
- rwlock_t lock;
+ spinlock_t lock;
struct iommu_domain *domain;
phys_addr_t pgtable;
};
@@ -263,12 +263,13 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
unsigned long addr = -1;
int ret = -ENOSYS;
- read_lock(&data->lock);
-
WARN_ON(!is_sysmmu_active(data));
+ spin_lock(&data->lock);
+
if (!IS_ERR(data->clk_master))
clk_enable(data->clk_master);
+
itype = (enum exynos_sysmmu_inttype)
__ffs(__raw_readl(data->sfrbase + REG_INT_STATUS));
if (WARN_ON(!((itype >= 0) && (itype < SYSMMU_FAULT_UNKNOWN))))
@@ -302,7 +303,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
if (!IS_ERR(data->clk_master))
clk_disable(data->clk_master);
- read_unlock(&data->lock);
+ spin_unlock(&data->lock);
return IRQ_HANDLED;
}
@@ -312,7 +313,7 @@ static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
unsigned long flags;
bool disabled = false;
- write_lock_irqsave(&data->lock, flags);
+ spin_lock_irqsave(&data->lock, flags);
if (!set_sysmmu_inactive(data))
goto finish;
@@ -330,7 +331,7 @@ static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
data->pgtable = 0;
data->domain = NULL;
finish:
- write_unlock_irqrestore(&data->lock, flags);
+ spin_unlock_irqrestore(&data->lock, flags);
if (disabled)
dev_dbg(data->sysmmu, "Disabled\n");
@@ -353,7 +354,7 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
int ret = 0;
unsigned long flags;
- write_lock_irqsave(&data->lock, flags);
+ spin_lock_irqsave(&data->lock, flags);
if (!set_sysmmu_active(data)) {
if (WARN_ON(pgtable != data->pgtable)) {
@@ -384,7 +385,7 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
dev_dbg(data->sysmmu, "Enabled\n");
finish:
- write_unlock_irqrestore(&data->lock, flags);
+ spin_unlock_irqrestore(&data->lock, flags);
return ret;
}
@@ -431,7 +432,7 @@ static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova,
unsigned long flags;
struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
- read_lock_irqsave(&data->lock, flags);
+ spin_lock_irqsave(&data->lock, flags);
if (is_sysmmu_active(data)) {
unsigned int maj;
@@ -465,7 +466,7 @@ static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova,
dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
}
- read_unlock_irqrestore(&data->lock, flags);
+ spin_unlock_irqrestore(&data->lock, flags);
}
void exynos_sysmmu_tlb_invalidate(struct device *dev)
@@ -473,7 +474,7 @@ void exynos_sysmmu_tlb_invalidate(struct device *dev)
unsigned long flags;
struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
- read_lock_irqsave(&data->lock, flags);
+ spin_lock_irqsave(&data->lock, flags);
if (is_sysmmu_active(data)) {
if (!IS_ERR(data->clk_master))
@@ -488,7 +489,7 @@ void exynos_sysmmu_tlb_invalidate(struct device *dev)
dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
}
- read_unlock_irqrestore(&data->lock, flags);
+ spin_unlock_irqrestore(&data->lock, flags);
}
static int exynos_sysmmu_probe(struct platform_device *pdev)
@@ -543,7 +544,7 @@ static int exynos_sysmmu_probe(struct platform_device *pdev)
}
data->sysmmu = dev;
- rwlock_init(&data->lock);
+ spin_lock_init(&data->lock);
INIT_LIST_HEAD(&data->node);
platform_set_drvdata(pdev, data);
--
1.7.9.5
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