Messages in this thread | | | Date | Wed, 9 Dec 2020 02:22:18 +0100 | From | Andrew Lunn <> | Subject | Re: [PATCH net v1 2/2] lan743x: boost performance: limit PCIe bandwidth requirement |
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> dma_sync_single_for_{cpu,device} is what you would need in order to make > a partial cache line invalidation. You would still need to unmap the > same address+length pair that was used for the initial mapping otherwise > the DMA-API debugging will rightfully complain.
But often you don't unmap it, you call dma_sync_single_for_device and put it back into the ring.
Andrew
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