Hi all: This series implements packed virtqueues. The code were tested with Tiwei's RFC V6 at https://lkml.org/lkml/2018/6/5/120. 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. This version were tested with: - Zerocopy (Out of Order) support - vIOMMU support - mergeable buffer on/off - busy polling on/off 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 virtio: introduce packed ring defines vhost: packed ring support vhost: event suppression for packed ring drivers/vhost/net.c | 144 ++---- drivers/vhost/scsi.c | 62 +-- drivers/vhost/vhost.c | 996 +++++++++++++++++++++++++++++++++---- drivers/vhost/vhost.h | 52 +- drivers/vhost/vsock.c | 42 +- include/uapi/linux/vhost.h | 7 + include/uapi/linux/virtio_config.h | 2 + include/uapi/linux/virtio_ring.h | 32 ++ 8 files changed, 1070 insertions(+), 267 deletions(-) -- 2.7.4
