On Thu, Jul 13, 2023 at 10:47:23AM -0400, Michael S. Tsirkin wrote: > There are a gazillion virtio drivers and most of them just use the > virtio API, without bothering with these micro-optimizations. virtio > already tracks addresses so mapping/unmapping them for DMA is easier > done in the core. It's only networking and only with XDP where the > difference becomes measureable. Yes, but now you two differing code paths (which then branch into another two with the fake DMA mappings). I'm really worried about the madness that follows like the USB dma mapping code that is a constant soure of trouble.
