Re: [PATCH v6 09/10] iommu/arm-smmu-v3: Skip cd sync if CD table isn't active

From: Michael Shavit
Date: Mon Aug 21 2023 - 06:16:48 EST


On Wed, Aug 16, 2023 at 9:20 PM Michael Shavit <mshavit@xxxxxxxxxx> wrote:
>
> This commit explicitly keeps track of whether a CD table is installed in
> an STE so that arm_smmu_sync_cd can skip the sync when unnecessary. This
> was previously achieved through the domain->devices list, but we are
> moving to a model where arm_smmu_sync_cd directly operates on a master
> and the master's CD table instead of a domain.
>
> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Reviewed-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
> Signed-off-by: Michael Shavit <mshavit@xxxxxxxxxx>
> ---
> Happy to drop this commit if we don't think it's useful.

Hi Will,
Do you have any recommendations for keeping or dropping this commit in
the end? It's only purpose is to minimize any potential performance
impact from the refactor but can certainly be dropped if you don't
think it's worth the complication.