Re: [PATCH 00/10] HMM updates for 5.1

From: Dan Williams
Date: Tue Mar 19 2019 - 14:42:13 EST


On Tue, Mar 19, 2019 at 10:45 AM Jerome Glisse <jglisse@xxxxxxxxxx> wrote:
>
> On Tue, Mar 19, 2019 at 10:33:57AM -0700, Dan Williams wrote:
> > On Tue, Mar 19, 2019 at 10:19 AM Jerome Glisse <jglisse@xxxxxxxxxx> wrote:
> > >
> > > On Tue, Mar 19, 2019 at 10:12:49AM -0700, Andrew Morton wrote:
> > > > On Tue, 19 Mar 2019 12:58:02 -0400 Jerome Glisse <jglisse@xxxxxxxxxx> wrote:
> > [..]
> > > > Also, the discussion regarding [07/10] is substantial and is ongoing so
> > > > please let's push along wth that.
> > >
> > > I can move it as last patch in the serie but it is needed for ODP RDMA
> > > convertion too. Otherwise i will just move that code into the ODP RDMA
> > > code and will have to move it again into HMM code once i am done with
> > > the nouveau changes and in the meantime i expect other driver will want
> > > to use this 2 helpers too.
> >
> > I still hold out hope that we can find a way to have productive
> > discussions about the implementation of this infrastructure.
> > Threatening to move the code elsewhere to bypass the feedback is not
> > productive.
>
> I am not threatening anything that code is in ODP _today_ with that
> patchset i was factering it out so that i could also use it in nouveau.
> nouveau is built in such way that right now i can not use it directly.
> But i wanted to factor out now in hope that i can get the nouveau
> changes in 5.2 and then convert nouveau in 5.3.
>
> So when i said that code will be in ODP it just means that instead of
> removing it from ODP i will keep it there and it will just delay more
> code sharing for everyone.

The point I'm trying to make is that the code sharing for everyone is
moving the implementation closer to canonical kernel code and use
existing infrastructure. For example, I look at 'struct hmm_range' and
see nothing hmm specific in it. I think we can make that generic and
not build up more apis and data structures in the "hmm" namespace.