Re: [PATCH net-next V2 0/3] rx busy polling support for virtio-net

On Wed, Jul 16, 2014 at 02:21:44PM +0800, Jason Wang wrote:

Hi all:

This series introduces the support for rx busy polling support. This
was useful for reduing the latency for a kvm guest. Patch 1-2
introduces helpers which is used for rx busy polling. Patch 3
implement the main function.

Test was done between a kvm guest and an external host. Two hosts were
connected through 40gb mlx4 cards. With both busy_poll and busy_read are
set to 50 in guest, 1 byte netperf tcp_rr shows 116% improvement:
transaction rate was increased from 9151.94 to 19787.37.

Changes from V1:
- split the patch info smaller ones
- add more details about test setup/configuration

Please review.

Generally I think we should let host know we are polling.
For example, kick the rq or something. Or maybe add another
io address.
Something like this would need a new feature flag though, so I'm fine
with just polling in guest until that is available.

Jason Wang (3):
  virtio-net: introduce helpers to enable and disable all NAPIs
  virtio-net: introduce virtnet_receive()
  virtio-net: rx busy polling support

 drivers/net/virtio_net.c | 234 ++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 221 insertions(+), 13 deletions(-)

-- 
1.8.3.1