mbox

[v3,0/3] net/virtio: Rx paths improvements

Message ID 20181220172718.9615-1-maxime.coquelin@redhat.com (mailing list archive)
Headers

Message

Maxime Coquelin Dec. 20, 2018, 5:27 p.m. UTC 
  First version of this series did merge out-of-order mergeable
and non-mergeable receive paths, but Intel STV team highlighted
some performance regression when using multiqueue with two cores
enqueueing descs on host, while a single core dequeues the
two queues.

I didn't manage to close the performance gap, so I decided to
give-up this refactoring. But while trying to optimize, I reworked
the meargeable function so that it looks like the in-order one.
I.e. descriptors are now dequeued in batches, so are descriptors
refilled. Doing that, I measure a perfromance gain of 6% when doing
rxonly microbenchmark with two cores on host, one in guest.


Changes since v2:
- Rebase after Jens' packed ring series
- Break refill loop if VQ_RING_DESC_CHAIN_END (Tiwei)
- Fixup commit message

Maxime Coquelin (3):
  net/virtio: inline refill and offload helpers
  net/virtio: add non-mergeable support to in-order path
  net/virtio: improve batching in mergeable path

 drivers/net/virtio/virtio_ethdev.c |  14 +-
 drivers/net/virtio/virtio_ethdev.h |   2 +-
 drivers/net/virtio/virtio_rxtx.c   | 257 ++++++++++++++++-------------
 3 files changed, 145 insertions(+), 128 deletions(-)