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

[Balbir Singh]

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, JÃrÃme 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?

Balbir Singh.