Messages in this thread | | | From | Sunil Kovvuri <> | Date | Mon, 6 Mar 2017 18:27:52 +0530 | Subject | Re: [PATCH 1/4] net: thunderx: Fix IOMMU translation faults |
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>> >> We are seeing a 0.75Mpps drop with IP forwarding rate due to that. >> Hence I have restricted calling DMA interfaces to only when IOMMU is enabled. > > What's 0.07Mpps as a percentage of baseline? On a correctly configured > coherent arm64 system, in the absence of an IOMMU, dma_map_*() is > essentially just virt_to_phys() behind a function call or two, so I'd be > interested to know where any non-trivial overhead might be coming from.
It's a 5% drop and yes device is configured as coherent. And the drop is due to additional function calls.
Thanks, Sunil.
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