Since acquiring read_lock is not more frequent than write_lock, it is not beneficial to use rwlock, this commit changes rwlock to spinlock.
Signed-off-by: Cho KyongHo <[email protected]> --- drivers/iommu/exynos-iommu.c | 32 ++++++++++++++++---------------- 1 files changed, 16 insertions(+), 16 deletions(-) diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c index 390f8b7..6793661 100644 --- a/drivers/iommu/exynos-iommu.c +++ b/drivers/iommu/exynos-iommu.c @@ -175,7 +175,7 @@ struct sysmmu_drvdata { void __iomem **sfrbases; struct clk *clk[2]; int activations; - rwlock_t lock; + spinlock_t lock; struct iommu_domain *domain; sysmmu_fault_handler_t fault_handler; unsigned long pgtable; @@ -259,7 +259,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev, BUG_ON((base0 + size0) <= base0); BUG_ON((size1 > 0) && ((base1 + size1) <= base1)); - read_lock_irqsave(&data->lock, flags); + spin_lock_irqsave(&data->lock, flags); if (!is_sysmmu_active(data)) goto finish; @@ -289,7 +289,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev, } } finish: - read_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); } static void __set_fault_handler(struct sysmmu_drvdata *data, @@ -297,9 +297,9 @@ static void __set_fault_handler(struct sysmmu_drvdata *data, { unsigned long flags; - write_lock_irqsave(&data->lock, flags); + spin_lock_irqsave(&data->lock, flags); data->fault_handler = handler; - write_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); } void exynos_sysmmu_set_fault_handler(struct device *dev, @@ -347,7 +347,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id) int i, ret = -ENOSYS; - read_lock(&data->lock); + spin_lock(&data->lock); WARN_ON(!is_sysmmu_active(data)); @@ -391,7 +391,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id) if (itype != SYSMMU_FAULT_UNKNOWN) sysmmu_unblock(data->sfrbases[i]); - read_unlock(&data->lock); + spin_unlock(&data->lock); return IRQ_HANDLED; } @@ -402,7 +402,7 @@ static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data) bool disabled = false; int i; - write_lock_irqsave(&data->lock, flags); + spin_lock_irqsave(&data->lock, flags); if (!set_sysmmu_inactive(data)) goto finish; @@ -419,7 +419,7 @@ 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, "(%s) Disabled\n", data->dbgname); @@ -442,7 +442,7 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data, int i, 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)) { @@ -481,7 +481,7 @@ static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data, dev_dbg(data->sysmmu, "(%s) Enabled\n", data->dbgname); finish: - write_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); return ret; } @@ -528,7 +528,7 @@ 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)) { int i; @@ -545,7 +545,7 @@ static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova) data->dbgname); } - read_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); } void exynos_sysmmu_tlb_invalidate(struct device *dev) @@ -553,7 +553,7 @@ 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)) { int i; @@ -569,7 +569,7 @@ void exynos_sysmmu_tlb_invalidate(struct device *dev) data->dbgname); } - read_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); } static int exynos_sysmmu_probe(struct platform_device *pdev) @@ -666,7 +666,7 @@ 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); __set_fault_handler(data, &default_fault_handler); -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
