On Tue, 2017-04-18 at 16:24 -0600, Jason Gunthorpe wrote: > Basically, all this list processing is a huge overhead compared to > just putting a helper call in the existing sg iteration loop of the > actual op. Particularly if the actual op is a no-op like no-mmu x86 > would use. Yes, I'm leaning toward that approach too. The helper itself could hang off the devmap though. > Since dma mapping is a performance path we must be careful not to > create intrinsic inefficiencies with otherwise nice layering :) > > Jason
