Hi: This series tries to access virtqueue metadata through kernel virtual address instead of copy_user() friends since they had too much overheads like checks, spec barriers or even hardware feature toggling. Test shows about 24% improvement on TX PPS. It should benefit other cases as well. Changes from V1: - instead of pinning pages, use MMU notifier to invalidate vmaps and remap duing metadata prefetch - fix build warning on MIPS Please review Jason Wang (3): vhost: generalize adding used elem vhost: fine grain userspace memory accessors vhost: access vq metadata through kernel virtual address drivers/vhost/net.c | 4 +- drivers/vhost/vhost.c | 362 ++++++++++++++++++++++++++++++++++++++---- drivers/vhost/vhost.h | 15 +- 3 files changed, 348 insertions(+), 33 deletions(-) -- 2.17.1
