iommu/iova: Put free_iova_mem() outside of spinlock iova_rbtree_lock

It is not necessary to put free_iova_mem() inside of spinlock/unlock
iova_rbtree_lock which only leads to more completion for the spinlock.
It has a small promote on the performance after the change. And also
rename private_free_iova() as remove_iova() because the function will not
free iova after that change.

Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1620647582-194621-1-git-send-email-chenxiang66@hisilicon.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index b7ecd5b..b6cf5f1 100644 (file)
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -412,12 +412,11 @@ private_find_iova(struct iova_domain *iovad, unsigned long pfn)
        return NULL;
 }
 
-static void private_free_iova(struct iova_domain *iovad, struct iova *iova)
+static void remove_iova(struct iova_domain *iovad, struct iova *iova)
 {
        assert_spin_locked(&iovad->iova_rbtree_lock);
        __cached_rbnode_delete_update(iovad, iova);
        rb_erase(&iova->node, &iovad->rbroot);
-       free_iova_mem(iova);
 }
 
 /**
@@ -452,8 +451,9 @@ __free_iova(struct iova_domain *iovad, struct iova *iova)
        unsigned long flags;
 
        spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
-       private_free_iova(iovad, iova);
+       remove_iova(iovad, iova);
        spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+       free_iova_mem(iova);
 }
 EXPORT_SYMBOL_GPL(__free_iova);
 
@@ -472,10 +472,13 @@ free_iova(struct iova_domain *iovad, unsigned long pfn)
 
        spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
        iova = private_find_iova(iovad, pfn);
-       if (iova)
-               private_free_iova(iovad, iova);
+       if (!iova) {
+               spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+               return;
+       }
+       remove_iova(iovad, iova);
        spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
-
+       free_iova_mem(iova);
 }
 EXPORT_SYMBOL_GPL(free_iova);
 
@@ -825,7 +828,8 @@ iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)
                if (WARN_ON(!iova))
                        continue;
 
-               private_free_iova(iovad, iova);
+               remove_iova(iovad, iova);
+               free_iova_mem(iova);
        }
 
        spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);