On Wed, Jan 20, 2016 at 10:47:45PM +0200, Adam Morrison wrote:
> On Wed, Jan 20, 2016 at 8:10 PM, Shaohua Li <[email protected]> wrote:
> > On Wed, Jan 20, 2016 at 01:21:03PM +0100, Joerg Roedel wrote:
> >> On Sun, Jan 10, 2016 at 07:37:59PM -0800, Shaohua Li wrote:
> >> > I don't know you already posted one. Roughly looked at the patches. We
> >> > are using exactly the same idea. I'm happy we pursue your patches. At
> >> > the first look, the per-cpu allocation in your patch doesn't check
> >> > pfn_limit, that could be wrong, but should be easy to fix. I'll take a
> >> > close look tomorrow.
> >>
> >> Sounds great. Your approaches with the per-cpu are pretty similar, so I
> >> would appreciate if you two come up with a combined patch-set?
> >
> > I'll do this if Adam doesn't object.
> 
> My understanding from the above is that the only issue with our
> patchset was not dealing with pfn_limit.  I can just fix that and
> repost, sounds good?

Sure, please do it. For the patches, I'm not comformatable about the
per-cpu deferred invalidation. One important benefit of IOMMU is
isolation. Deferred invalidation already loose the isolation, per-cpu
invalidation loose further. It would be better we can flush all per-cpu
invalidation entries if one cpu hits its per-cpu limit. Also you'd
better look at CPU hotplug. We don't want to lose the invalidation
entries if one cpu is hot removed.

The per-cpu iova implementation looks unnecessary complicated. I know
you are referring the paper, but the whole point is batch
allocation/free.

Please cc me if you post the patches again. I don't subscribe the iommu
list.

Thanks,
Shaohua
_______________________________________________
iommu mailing list
[email protected]
https://lists.linuxfoundation.org/mailman/listinfo/iommu

Reply via email to