Merge branch 'vxlan_rco'
Tom Herbert says:
====================
net: Remote checksum offload for VXLAN
This patch set adds support for remote checksum offload in VXLAN.
The remote checksum offload is generalized by creating a common
function (remcsum_adjust) that does the work of modifying the
checksum in remote checksum offload. This function can be called
from normal or GRO path. GUE was modified to use this function.
To support RCO is VXLAN we use the 9th bit in the reserved
flags to indicated remote checksum offload. The start and offset
values are encoded n a compressed form in the low order (reserved)
byte of the vni field.
Remote checksum offload is described in
https://tools.ietf.org/html/draft-herbert-remotecsumoffload-01
Changes in v2:
- Add udp_offload_callbacks which has GRO functions that take a
udp_offload pointer argument. This argument can be used to retrieve
a per port structure of the encapsulation for use in gro processing
(mostly by doing container_of on the structure).
- Use the 10th bit in VXLAN flags for RCO which does not seem to
conflict with other proposals at this time (ie. VXLAN-GPE and
VXLAN-GPB)
- Require that RCO must be explicitly enabled on the receiver
as well as the sender.
Tested by running 200 TCP_STREAM connections with VXLAN (over IPv4).
With UDP checksums and Remote Checksum Offload
IPv4
Client
11.84% CPU utilization
Server
12.96% CPU utilization
9197 Mbps
IPv6
Client
12.46% CPU utilization
Server
14.48% CPU utilization
8963 Mbps
With UDP checksums, no remote checksum offload
IPv4
Client
15.67% CPU utilization
Server
14.83% CPU utilization
9094 Mbps
IPv6
Client
16.21% CPU utilization
Server
14.32% CPU utilization
9058 Mbps
No UDP checksums
IPv4
Client
15.03% CPU utilization
Server
23.09% CPU utilization
9089 Mbps
IPv6
Client
16.18% CPU utilization
Server
26.57% CPU utilization
8954 Mbps
====================
Signed-off-by: David S. Miller <davem@davemloft.net>