On 07/02/2018 03:56 PM, Marvin Liu wrote:
In latest virtio-spec, new feature bit VIRTIO_F_IN_ORDER was introduced.
When this feature has been negotiated, virtio driver will use
descriptors in ring order: starting from offset 0 in the table, and
wrapping around at the end of the table. Vhost devices will always use
descriptors in the same order in which they have been made available.
This can reduce virtio accesses to used ring.
Based on updated virtio-spec, this series realized IN_ORDER prototype
in virtio driver. Due to new [RT]x path added into selection, also add
two new parameters mrg_rx and in_order into virtio-user vdev parameters
list. This will allow user to configure feature bits thus can impact
[RT]x path selection.
Performance of virtio user with IN_ORDER feature:
Platform: Purely
CPU: Intel(R) Xeon(R) Platinum 8160 CPU @ 2.10GHz
DPDK baseline: 18.05
Setup: testpmd with vhost vdev + testpmd with virtio vdev
+--------------+----------+----------+---------+
|Vhost->Virtio |1 Queue |2 Queues |4 Queues |
+--------------+----------+----------+---------+
|Inorder |12.0Mpps |24.2Mpps |26.0Mpps |
|Normal |12.1Mpps |18.5Mpps |18.9Mpps |
+--------------+----------+----------+---------+
+--------------+----------+----------------+---------+
|Virtio->Vhost |1 Queue |2 Queues |4 Queues |
+--------------+----------+----------------+---------+
|Inorder |13.8Mpps |10.7 ~ 15.2Mpps |11.5Mpps |
|Normal |13.3Mpps |9.8 ~ 14Mpps |10.5Mpps |
+--------------+----------+----------------+---------+
+---------+----------+----------------+----------------+
|Loopback |1 Queue |2 Queues |4 Queues |
+---------+----------+----------------+----------------+
|Inorder |7.4Mpps |9.1 ~ 11.6Mpps |10.5 ~ 11.3Mpps |
+---------+----------+----------------+----------------+
|Normal |7.5Mpps |7.7 ~ 9.0Mpps |7.6 ~ 7.8Mpps |
+---------+----------+----------------+----------------+
v5:
- disable simple Tx when in-order negotiated
- doc update
v4:
- disable simple [RT]x function for ARM
- squash doc update into relevant patches
- fix git-check-log and checkpatch errors
v3:
- refine [RT]x function selection logic
- fix in-order mergeable packets index error
- combine unsupport mask patch
- doc virtio in-order update
- fix checkpatch error
v2:
- merge to latest dpdk-net-virtio
- not use in_direct for normal xmit packets
- update available ring for each descriptor
- clean up IN_ORDER xmit function
- unmask feature bits when disabled in_order or mgr_rxbuf
- extract common part between IN_ORDER and normal functions
- update performance result
Marvin Liu (9):
vhost: advertise support in-order feature
net/virtio: add in-order feature bit definition
net/virtio-user: add unsupported features mask
net/virtio-user: add mrg-rxbuf and in-order vdev parameters
net/virtio: free in-order descriptors before device start
net/virtio: extract common part for in-order functions
net/virtio: support in-order Rx and Tx
net/virtio: add in-order Rx/Tx into selection
net/virtio: advertise support in-order feature
doc/guides/nics/virtio.rst | 23 +-
drivers/net/virtio/virtio_ethdev.c | 32 +-
drivers/net/virtio/virtio_ethdev.h | 7 +
drivers/net/virtio/virtio_pci.h | 8 +
drivers/net/virtio/virtio_rxtx.c | 639 ++++++++++++++++--
.../net/virtio/virtio_user/virtio_user_dev.c | 30 +-
.../net/virtio/virtio_user/virtio_user_dev.h | 4 +-
drivers/net/virtio/virtio_user_ethdev.c | 47 +-
drivers/net/virtio/virtqueue.c | 8 +
drivers/net/virtio/virtqueue.h | 2 +
lib/librte_vhost/socket.c | 6 +
lib/librte_vhost/vhost.h | 10 +-
12 files changed, 736 insertions(+), 80 deletions(-)
Applied to dpdk-next-virtio/master.
Thanks,
Maxime