答复: 答复: 答复: [PATCH V2] vfio dma_map/unmap: optimized for hugetlbfs pages

From: Maoming (maoming, Cloud Infrastructure Service Product Dept.)
Date: Tue Sep 01 2020 - 08:47:11 EST


>
> On 2020/8/28 下午10:24, Peter Xu wrote:
> > On Fri, Aug 28, 2020 at 09:23:08AM +0000, Maoming (maoming, Cloud
> Infrastructure Service Product Dept.) wrote:
> >> In hugetlb_put_pfn(), I delete unpin_user_pages_dirty_lock() and use some
> simple code to put hugetlb pages.
> >> Is this right?
> > I think we should still use the APIs because of the the same reason.
> > However again I don't know the performance impact of that to your
> > patch, but I still think that could be done inside gup itself when
> > needed (e.g., a special path for hugetlbfs for [un]pinning continuous
> > pages; though if that's the case that could be something to be discussed on
> -mm then as a separate patch, imho).
> >
> > Thanks,
>
>
> +1, we should make this as a generic optimization instead of VFIO
> specific consider there're a lot of GUP users.
>
> Thanks
>


Thanks for your suggestions.
You are right, I will fix it in the next version.