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    SubjectRe: [PATCH 1/4] net: thunderx: Fix IOMMU translation faults
    >>
    >> 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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