Re: [PATCH v1 00/16] iommufd: Add vIOMMU infrastructure (Part-4 vCMDQ)

Nicolin Chen
2025-04-24T15:54:33Z

On Thu, Apr 24, 2025 at 08:21:08AM +0000, Tian, Kevin wrote:
> > From: Nicolin Chen <nicolinc@nvidia.com>
> > Sent: Friday, April 11, 2025 2:38 PM
> >
> [...]
> > This is a big
> > improvement since there is no VM Exit during an invalidation, compared to
> > the traditional invalidation pathway by trapping a guest-own invalidation
> > queue and forwarding those commands/requests to the host kernel that will
> > eventually fill a HW-owned queue to execute those commands.
> >
>
> any data to show how big the improvements could be in major
> IOMMU usages (kernel dma, user dma and sva)?

I thought I mentioned about the percentage of the gain somewhere
but seemingly not in this series.. Will add.

Thanks!
Nicolin