I'm not sure whether the compiler can optimize it, but move it out will
be better. At least, it does not require lock protection.
Signed-off-by: Zhen Lei <thunder.leiz...@huawei.com>
---
drivers/iommu/iova.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index 23abe84..68754e4 100644
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -127,23 +127,16 @@ __cached_rbnode_delete_update(struct iova_domain *iovad,
struct iova *free)
*cached_node = rb_prev(&free->node);
}
-/*
- * Computes the padding size required, to make the start address
- * naturally aligned on the power-of-two order of its size
- */
-static unsigned long
-iova_get_pad_size(unsigned long size, unsigned long limit_pfn)
-{
- return (limit_pfn + 1 - size) & (__roundup_pow_of_two(size) - 1);
-}
-
static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
unsigned long size, unsigned long limit_pfn,
struct iova *new, bool size_aligned)
{
struct rb_node *prev, *curr;
unsigned long flags;
- unsigned long pad_size = 0;
+ unsigned long pad_mask, pad_size = 0;
+
+ if (size_aligned)
+ pad_mask = __roundup_pow_of_two(size) - 1;
/* Walk the tree backwards */
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
@@ -157,8 +150,13 @@ static int __alloc_and_insert_iova_range(struct
iova_domain *iovad,
else if (limit_pfn < curr_iova->pfn_hi)
goto adjust_limit_pfn;
else {
+ /*
+ * Computes the padding size required, to make the start
+ * address naturally aligned on the power-of-two order
+ * of its size
+ */
if (size_aligned)
- pad_size = iova_get_pad_size(size, limit_pfn);
+ pad_size = (limit_pfn + 1 - size) & pad_mask;
if ((curr_iova->pfn_hi + size + pad_size) <= limit_pfn)
break; /* found a free slot */
}
--
2.5.0
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