On Mon, Jul 16, 2018 at 11:28:03AM +0800, Jason Wang wrote: > Hi all: > > This series implements packed virtqueues. The code were tested with > Tiwei's guest driver series at https://patchwork.ozlabs.org/cover/942297/ > > > Pktgen test for both RX and TX does not show obvious difference with > split virtqueues. The main bottleneck is the guest Linux driver, since > it can not stress vhost for a 100% CPU utilization. A full TCP > benchmark is ongoing. Will test virtio-net pmd as well when it was > ready. Well the question then is why we should bother merging this if this doesn't give a performance gain. Do you see a gain in CPU utilization maybe? If not - let's wait for that TCP benchmark result? > Notes: > - This version depends on Tiwei's series at https://patchwork.ozlabs.org/cover/942297/ > > This version were tested with: > > - Zerocopy (Out of Order) support > - vIOMMU support > - mergeable buffer on/off > - busy polling on/off > - vsock (nc-vsock) > > Changes from V1: > - drop uapi patch and use Tiwei's > - split the enablement of packed virtqueue into a separate patch > > Changes from RFC V5: > > - save unnecessary barriers during vhost_add_used_packed_n() > - more compact math for event idx > - fix failure of SET_VRING_BASE when avail_wrap_counter is true > - fix not copy avail_wrap_counter during GET_VRING_BASE > - introduce SET_VRING_USED_BASE/GET_VRING_USED_BASE for syncing last_used_idx > - rename used_wrap_counter to last_used_wrap_counter > - rebase to net-next > > Changes from RFC V4: > > - fix signalled_used index recording > - track avail index correctly > - various minor fixes > > Changes from RFC V3: > > - Fix math on event idx checking > - Sync last avail wrap counter through GET/SET_VRING_BASE > - remove desc_event prefix in the driver/device structure > > Changes from RFC V2: > > - do not use & in checking desc_event_flags > - off should be most significant bit > - remove the workaround of mergeable buffer for dpdk prototype > - id should be in the last descriptor in the chain > - keep _F_WRITE for write descriptor when adding used > - device flags updating should use ADDR_USED type > - return error on unexpected unavail descriptor in a chain > - return false in vhost_ve_avail_empty is descriptor is available > - track last seen avail_wrap_counter > - correctly examine available descriptor in get_indirect_packed() > - vhost_idx_diff should return u16 instead of bool > > Changes from RFC V1: > > - Refactor vhost used elem code to avoid open coding on used elem > - Event suppression support (compile test only). > - Indirect descriptor support (compile test only). > - Zerocopy support. > - vIOMMU support. > - SCSI/VSOCK support (compile test only). > - Fix several bugs > > Jason Wang (8): > vhost: move get_rx_bufs to vhost.c > vhost: hide used ring layout from device > vhost: do not use vring_used_elem > vhost_net: do not explicitly manipulate vhost_used_elem > vhost: vhost_put_user() can accept metadata type > vhost: packed ring support > vhost: event suppression for packed ring > vhost: enable packed virtqueues > > drivers/vhost/net.c | 143 ++----- > drivers/vhost/scsi.c | 62 +-- > drivers/vhost/vhost.c | 994 ++++++++++++++++++++++++++++++++++++++++----- > drivers/vhost/vhost.h | 55 ++- > drivers/vhost/vsock.c | 42 +- > include/uapi/linux/vhost.h | 7 + > 6 files changed, 1035 insertions(+), 268 deletions(-) > > -- > 2.7.4
