Messages in this thread Patch in this message | | | From | John Garry <> | Subject | [PATCH v3 4/4] iommu: avoid taking iova_rbtree_lock twice | Date | Thu, 12 Nov 2020 19:28:29 +0800 |
| |
From: Cong Wang <xiyou.wangcong@gmail.com>
Both find_iova() and __free_iova() take iova_rbtree_lock, there is no reason to take and release it twice inside free_iova().
Fold them into one critical section by calling the unlock versions instead.
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: John Garry <john.garry@huawei.com> --- drivers/iommu/iova.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index 386005055aca..3b32e6746c70 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -398,10 +398,14 @@ EXPORT_SYMBOL_GPL(__free_iova); void free_iova(struct iova_domain *iovad, unsigned long pfn) { - struct iova *iova = find_iova(iovad, pfn); + unsigned long flags; + struct iova *iova; + spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); + iova = private_find_iova(iovad, pfn); if (iova) - __free_iova(iovad, iova); + private_free_iova(iovad, iova); + spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); } EXPORT_SYMBOL_GPL(free_iova); -- 2.26.2
| |