Hi Robin, On Wed, Sep 12, 2018 at 04:24:11PM +0100, Robin Murphy wrote: > John raised the issue[1] that we have some unnecessary refcount contention > in the DMA ops path which shows scalability problems now that we have more > real high-performance hardware using iommu-dma. The x86 IOMMU drivers are > sidestepping this by stashing domain references in archdata, but since > that's not very nice for architecture-agnostic code, I think it's time to > look at a generic API-level solution. > > These are a couple of quick patches based on the idea I had back when > first implementing iommu-dma, but didn't have any way to justify at the > time. However, the reports of 10-25% better networking performance on v1 > suggest that it's very worthwhile (and far more significant than I ever > would have guessed). > > As far as merging goes, I don't mind at all whether this goes via IOMMU, > or via dma-mapping provided Joerg's happy to ack it.
I think it makes most sense for Joerg to take this series via his tree. Anyway, I've been running them on my TX2 box and things are happy enough, so: Tested-by: Will Deacon <[email protected]> Will _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
