[PATCH v3 3/3] iommu/io-pgtable: Avoid redundant TLB syncs

[Will Deacon]

On Tue, Jan 26, 2016 at 05:13:15PM +0000, Robin Murphy wrote:
> In certain unmapping situations it is quite possible to end up issuing
> back-to-back TLB synchronisations, which at best is a waste of time and
> effort, and at worst causes some hardware to get rather confused. Whilst
> the pagetable implementations, or the IOMMU drivers, or both, could keep
> track of things to avoid this happening, it seems to make the most sense
> to prevent code duplication and add some simple state tracking in the
> common interface between the two.
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> Signed-off-by: Robin Murphy <robin.murphy at arm.com>
> ---
>  drivers/iommu/io-pgtable.h | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)

Acked-by: Will Deacon <will.deacon at arm.com>

Will