On Tue, 2016-10-25 at 11:39 -0400, Alexander Duyck wrote: > The ARM architecture provides a mechanism for deferring cache line > invalidation in the case of map/unmap.  This patch makes use of this > mechanism to avoid unnecessary synchronization. > > A secondary effect of this change is that the portion of the page that > has > been synchronized for use by the CPU should be writable and could be > passed > up the stack (at least on ARM). > > The last bit that occurred to me is that on architectures where the > sync_for_cpu call invalidates cache lines we were prefetching and then > invalidating the first 128 bytes of the packet.  To avoid that I have > moved > the sync up to before we perform the prefetch and allocate the skbuff so > that we can actually make use of it. > > Signed-off-by: Alexander Duyck >  Acked-by: Jeff Kirsher