Re: [PATCH] mm: thp: register mm for khugepaged when merging vma for shmem

[Yang Shi]

On 6/21/18 3:24 PM, Yang Shi wrote:
> On 6/21/18 3:10 PM, Kirill A. Shutemov wrote:
> > On Fri, Jun 22, 2018 at 05:40:47AM +0800, Yang Shi wrote:
> > > When merging anonymous page vma, if the size of vam can fit in at least
> > s/vam/vma/
> >
> > > one hugepage, the mm will be registered for khugepaged for collapsing
> > > THP in the future.
> > >
> > > But, it skips shmem vma. Doing so for shmem too when merging vma in
> > > order to increase the odd to collapse hugepage by khugepaged.
> > Good catch. Thanks.
> >
> > I think the fix incomplete. We shouldn't require vma->anon_vma for 
> > shmem,
> > only for anonymous mappings. We don't support file-private THPs.
>
> So you mean, shmem_file(vma->vm_file) && PageAnon(page)?

I got your point. Please disregard the question.

> > > Also increase the count of shmem THP collapse. It looks missed before.
> > Separate patch, please.
>
> Sure.
>
> Thanks,
> Yang
>
> >