On Fri, Nov 24, 2023 at 04:59:38PM +0100, Niklas Schnelle wrote: > This should be as easy as adding > > #define memcpy_toio_64(to, from) zpci_memcpy_toio(to, from, 64) > > to arch/s390/include/asm/io.h. I'm wondering if we should do that as > part of this series. It's not as good as a special case but probably > better than the existing loop. Makes sense > I don't think we have any existing in-kernel users of memcpy_toio() on > s390 so far though so I'd like to give this some extra testing. Could > you share instructions on how to exercise the code path of patch 2 on a > ConnectX-5 or 6? Is this exercised e.g. when using NVMe-oF RDMA? Simply boot and look at pr_debug from mlx5 to see if writecombining is on or off - you want to see on. Thanks, Jason
