| Message ID | 002d01ce797b$49c441a0$dd4cc4e0$@samsung.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
Hi, On Friday, July 05, 2013 09:29:26 PM Cho KyongHo 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. This change is not of a "fix type" and is not required to make the driver work so it would probably be best to move it to the end of a patch series (IOW just making it the last patch in the series). Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics > Signed-off-by: Cho KyongHo <pullip.cho@samsung.com> > --- > 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); -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> From: Bartlomiej Zolnierkiewicz [mailto:b.zolnierkie@samsung.com] > Sent: Saturday, July 13, 2013 12:31 AM > > Hi, > > On Friday, July 05, 2013 09:29:26 PM Cho KyongHo 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. > > This change is not of a "fix type" and is not required to make the driver > work so it would probably be best to move it to the end of a patch series > (IOW just making it the last patch in the series). > Thank you for advice. I will do that in the next patchset :) Cho KyongHo. > Best regards, > -- > Bartlomiej Zolnierkiewicz > Samsung R&D Institute Poland > Samsung Electronics > > > Signed-off-by: Cho KyongHo <pullip.cho@samsung.com> > > --- > > 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); -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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);
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 | 32 ++++++++++++++++---------------- 1 files changed, 16 insertions(+), 16 deletions(-)