Re: [PATCH v5 2/2] kvm: Use huge pages for DAX-backed files

From: Barret Rhoden
Date: Tue Jan 07 2020 - 14:19:11 EST


Hi -

On 1/7/20 2:05 PM, Sean Christopherson wrote:
On Mon, Dec 16, 2019 at 11:05:26AM -0500, Barret Rhoden wrote:
On 12/13/19 12:19 PM, Sean Christopherson wrote:
Teaching thp_adjust() how to handle 1GB wouldn't be a bad thing. It's
unlikely THP itself will support 1GB pages any time soon, but having the
logic there wouldn't hurt anything.


Cool. This was my main concern - I didn't want to break THP.

I'll rework the series based on all of your comments.

Hopefully you haven't put too much effort into the rework, because I want
to commandeer the proposed changes and use them as the basis for a more
aggressive overhaul of KVM's hugepage handling. Ironically, there's a bug
in KVM's THP handling that I _think_ can be avoided by using the DAX
approach of walking the host PTEs.

I'm in the process of testing, hopefully I'll get a series sent out later
today. If not, I should at least be able to provide an update.

Nice timing. I was just about to get back to this, so I haven't put any time in yet. =)

Please CC me, and I'll try your patches out on my end.

Thanks,

Barret