Message ID | 004101ce89f3$90200980$b0601c80$@samsung.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Fri, Jul 26, 2013 at 4:30 AM, Cho KyongHo <pullip.cho@samsung.com> wrote: > 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 <pullip.cho@samsung.com> Reviewed-by: Grant Grundler <grundler@chromium.org> cheers, grant > --- > 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 c62c244..51e5b35 100644 > --- a/drivers/iommu/exynos-iommu.c > +++ b/drivers/iommu/exynos-iommu.c > @@ -187,7 +187,7 @@ 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; > @@ -287,7 +287,7 @@ 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, > @@ -371,7 +371,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id) > > if (client) > spin_lock(&client->lock); > - read_lock(&data->lock); > + spin_lock(&data->lock); > > if (i == data->nsfrs) { > itype = SYSMMU_FAULT_UNKNOWN; > @@ -402,7 +402,7 @@ 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); > if (client) > spin_unlock(&client->lock); > > @@ -429,7 +429,7 @@ 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); > > @@ -446,7 +446,7 @@ static bool __sysmmu_disable(struct sysmmu_drvdata *data) > data->activations); > } > > - write_unlock_irqrestore(&data->lock, flags); > + spin_unlock_irqrestore(&data->lock, flags); > > return disabled; > } > @@ -493,7 +493,7 @@ 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; > @@ -511,7 +511,7 @@ 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; > } > @@ -602,7 +602,7 @@ 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); > @@ -615,7 +615,7 @@ 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); > } > } > > @@ -630,7 +630,7 @@ 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; > @@ -646,7 +646,7 @@ 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); > } > } > > @@ -735,7 +735,7 @@ 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); > INIT_LIST_HEAD(&data->node); > > platform_set_drvdata(pdev, data); > @@ -749,11 +749,11 @@ 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; > } > > @@ -761,11 +761,11 @@ 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 > >
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c index c62c244..51e5b35 100644 --- a/drivers/iommu/exynos-iommu.c +++ b/drivers/iommu/exynos-iommu.c @@ -187,7 +187,7 @@ 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; @@ -287,7 +287,7 @@ 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, @@ -371,7 +371,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id) if (client) spin_lock(&client->lock); - read_lock(&data->lock); + spin_lock(&data->lock); if (i == data->nsfrs) { itype = SYSMMU_FAULT_UNKNOWN; @@ -402,7 +402,7 @@ 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); if (client) spin_unlock(&client->lock); @@ -429,7 +429,7 @@ 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); @@ -446,7 +446,7 @@ static bool __sysmmu_disable(struct sysmmu_drvdata *data) data->activations); } - write_unlock_irqrestore(&data->lock, flags); + spin_unlock_irqrestore(&data->lock, flags); return disabled; } @@ -493,7 +493,7 @@ 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; @@ -511,7 +511,7 @@ 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; } @@ -602,7 +602,7 @@ 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); @@ -615,7 +615,7 @@ 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); } } @@ -630,7 +630,7 @@ 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; @@ -646,7 +646,7 @@ 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); } } @@ -735,7 +735,7 @@ 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); INIT_LIST_HEAD(&data->node); platform_set_drvdata(pdev, data); @@ -749,11 +749,11 @@ 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; } @@ -761,11 +761,11 @@ 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
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 <pullip.cho@samsung.com> --- drivers/iommu/exynos-iommu.c | 36 ++++++++++++++++++------------------ 1 files changed, 18 insertions(+), 18 deletions(-)