Re: [PATCH v2 5/8] iommu/arm-smmu-v3: Precompute the invalidation commands

[Mostafa Saleh <smostafa@google.com>]

On Mon, Jul 06, 2026 at 01:26:42PM -0300, Jason Gunthorpe wrote:
> Store the required cmd data in the tlbi and just copy it out when
> processing each item in the invs list. The cmd form only depends on
> if the instance supports RIL or not, otherwise it is always the same.
> 
> This avoids redundant calculations for each invs entry.

I do not understand how does this avoids redundant calculation?
This would be the case if the domain shares multiple SMMUs,
otherwise, a range TLB invalidation should be unique and can not be
reused.
And in that case I am not sure that would be noticeable with modern
CPUs/compilers.

Thanks,
Mostafa

> 
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 132 +++++++++++---------
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h |  11 ++
>  2 files changed, 81 insertions(+), 62 deletions(-)
> 
> 2.43.0
>