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> --- drivers/iommu/exynos-iommu.c | 36 ++++++++++++++++++------------------ 1 files changed, 18 insertions(+), 18 deletions(-) diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c index 56aead9..2d16fc0 100644 --- a/drivers/iommu/exynos-iommu.c +++ b/drivers/iommu/exynos-iommu.c @@ -185,7 +185,7 @@ struct sysmmu_drvdata { struct clk *clk; struct clk *clk_master; int activations; - rwlock_t lock; + spinlock_t lock; struct iommu_domain *domain; bool runtime_active; unsigned long pgtable; @@ -285,7 +285,7 @@ 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; @@ -319,7 +319,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev, clk_disable(data->clk_master); finish: - read_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); } static void show_fault_information(const char *name, @@ -372,7 +372,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id) clk_enable(data->clk_master); if (client) spin_lock(&client->lock); - read_lock(&data->lock); + spin_lock(&data->lock); if (i == data->nsfrs) { itype = SYSMMU_FAULT_UNKNOWN; @@ -405,7 +405,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id) clk_disable(data->clk_master); - read_unlock(&data->lock); + spin_unlock(&data->lock); if (client) spin_unlock(&client->lock); @@ -432,7 +432,7 @@ static bool __sysmmu_disable(struct sysmmu_drvdata *data) bool disabled; unsigned long flags; - write_lock_irqsave(&data->lock, flags); + spin_lock_irqsave(&data->lock, flags); disabled = set_sysmmu_inactive(data); @@ -449,7 +449,7 @@ static bool __sysmmu_disable(struct sysmmu_drvdata *data) data->activations); } - write_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); return disabled; } @@ -503,7 +503,7 @@ static int __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)) { data->pgtable = pgtable; data->domain = domain; @@ -521,7 +521,7 @@ static int __sysmmu_enable(struct sysmmu_drvdata *data, if (WARN_ON(ret < 0)) set_sysmmu_inactive(data); /* decrement count */ - write_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); return ret; } @@ -612,7 +612,7 @@ static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova) data = dev_get_drvdata(client->sysmmu[i]); - read_lock_irqsave(&data->lock, flags); + spin_lock_irqsave(&data->lock, flags); if (is_sysmmu_active(data) && data->runtime_active) { int i; clk_enable(data->clk_master); @@ -625,7 +625,7 @@ static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova) "disabled. Skipping TLB invalidation @ %#lx\n", iova); } - read_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); } } @@ -640,7 +640,7 @@ void exynos_sysmmu_tlb_invalidate(struct device *dev) data = dev_get_drvdata(client->sysmmu[i]); - read_lock_irqsave(&data->lock, flags); + spin_lock_irqsave(&data->lock, flags); if (is_sysmmu_active(data) && data->runtime_active) { int i; @@ -656,7 +656,7 @@ void exynos_sysmmu_tlb_invalidate(struct device *dev) } else { dev_dbg(dev, "disabled. Skipping TLB invalidation\n"); } - read_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); } } @@ -745,7 +745,7 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev) data->runtime_active = !pm_runtime_enabled(dev); - rwlock_init(&data->lock); + spin_lock_init(&data->lock); platform_set_drvdata(pdev, data); dev_dbg(dev, "Probed and initialized\n"); @@ -758,11 +758,11 @@ static int sysmmu_suspend(struct device *dev) { struct sysmmu_drvdata *data = dev_get_drvdata(dev); unsigned long flags; - read_lock_irqsave(&data->lock, flags); + spin_lock_irqsave(&data->lock, flags); if (is_sysmmu_active(data) && (!pm_runtime_enabled(dev) || data->runtime_active)) __sysmmu_disable_nocount(data); - read_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); return 0; } @@ -770,11 +770,11 @@ static int sysmmu_resume(struct device *dev) { struct sysmmu_drvdata *data = dev_get_drvdata(dev); unsigned long flags; - read_lock_irqsave(&data->lock, flags); + spin_lock_irqsave(&data->lock, flags); if (is_sysmmu_active(data) && (!pm_runtime_enabled(dev) || data->runtime_active)) __sysmmu_enable_nocount(data); - read_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); return 0; } #endif -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html