Re: [PATCH] mm/doc: add usage description for migrate_vma_*()

From: Alistair Popple
Date: Mon Sep 14 2020 - 21:05:20 EST


On Friday, 11 September 2020 3:25:14 AM AEST Jason Gunthorpe wrote:
> On Thu, Sep 10, 2020 at 10:56:57AM -0600, Jonathan Corbet wrote:
> > On Wed, 9 Sep 2020 14:29:56 -0700
> >
> > Ralph Campbell <rcampbell@xxxxxxxxxx> wrote:
> > > The migrate_vma_setup(), migrate_vma_pages(), and migrate_vma_finalize()
> > > API usage by device drivers is not well documented.
> > > Add a description for how device drivers are expected to use it.
> > >
> > > Signed-off-by: Ralph Campbell <rcampbell@xxxxxxxxxx>
> > >
> > > There shouldn't be any merge conflict with my previous patch which
> > > touched hmm.rst but since Jonathan Corbet took my last patch, perhaps he
> > > would like to take this one through his tree too.
> >
> > I'm happy to take it, but it certainly needs an ack from somebody who
> > understands HMM better than I do.
>
> Ralph wrote all the in kernel tests for this API, so I think he is
> well positioned to write the documentation :)

I have recently read through most of the code to get back up to date with
recent HMM developments and the documentation here didn't conflict with my
understanding based on the code. The description of pgmap_owner is good as
it's usage wasn't immediately clear on the first code read through. So feel
free to add:

Reviewed-by: Alistair Popple <apopple@xxxxxxxxxx>

> Jason