Re: [HMM 00/15] HMM (Heterogeneous Memory Management) v22

[Jerome Glisse]

 On Thu, Jun 01, 2017 at 12:04:02PM +1000, Balbir Singh wrote:
> On Thu, May 25, 2017 at 3:53 AM, Jerome Glisse <jglisse@xxxxxxxxxx> wrote:
> > On Wed, May 24, 2017 at 11:55:12AM +1000, Balbir Singh wrote:
> >> On Tue, May 23, 2017 at 2:51 AM, Jérôme Glisse <jglisse@xxxxxxxxxx> wrote:
> >> > Patchset is on top of mmotm mmotm-2017-05-18, git branch:
> >> >
> >> > https://cgit.freedesktop.org/~glisse/linux/log/?h=hmm-v22
> >> >
> >> > Change since v21 is adding back special refcounting in put_page() to
> >> > catch when a ZONE_DEVICE page is free (refcount going from 2 to 1
> >> > unlike regular page where a refcount of 0 means the page is free).
> >> > See patch 8 of this serie for this refcounting. I did not use static
> >> > keys because it kind of scares me to do that for an inline function.
> >> > If people strongly feel about this i can try to make static key works
> >> > here. Kirill will most likely want to review this.
> >> >
> >> >
> >> > Everything else is the same. Below is the long description of what HMM
> >> > is about and why. At the end of this email i describe briefly each patch
> >> > and suggest reviewers for each of them.
> >> >
> >> >
> >> > Heterogeneous Memory Management (HMM) (description and justification)
> >> >
> >>
> >> Thanks for the patches! These patches are very helpful. There are a
> >> few additional things we would need on top of this (once HMM the base
> >> is merged)
> >>
> >> 1. Support for other architectures, we'd like to make sure we can get
> >> this working for powerpc for example. As a first step we have
> >> ZONE_DEVICE enablement patches, but I think we need some additional
> >> patches for iomem space searching and memory hotplug, IIRC
> >> 2. HMM-CDM and physical address based migration bits. In a recent RFC
> >> we decided to try and use the HMM CDM route as a route to implementing
> >> coherent device memory as a starting point. It would be nice to have
> >> those patches on top of these once these make it to mm -
> >> https://lwn.net/Articles/720380/
> >>
> >
> > I intend to post the updated HMM CDM patchset early next week. I am
> > tie in couple internal backport but i should be able to resume work
> > on that this week.
> >
> 
> Thanks, I am looking at the HMM CDM branch and trying to forward port
> and see what the results look like on top of HMM-v23. Do we have a timeline
> for the v23 merge?
> 

So i am moving to new office and it has taken me more time than i thought
to pack stuff. Attach is first step of CDM on top of lastest HMM. I hope
to have more time tomorrow or next week to finish rebasing patches and to
run some test with stolen ram as CDM memory.

Jérôme