Re: [Patch v2 3/3] iommu: avoid taking iova_rbtree_lock twice

From: Cong Wang
Date: Sat Nov 30 2019 - 01:04:08 EST


On Fri, Nov 29, 2019 at 5:34 AM John Garry <john.garry@xxxxxxxxxx> wrote:
>
> On 29/11/2019 00:48, Cong Wang wrote:
> > 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 the critical section by calling the unlock
> > versions instead.
>
> Since generally the iova would be non-NULL, this seems a reasonable
> change (which could be mentioned in the commit log)

I think it is too obvious to mention it. There are many things we can
mention but we should only mention what's necessary, right?

Thanks.