Merge branch 'csums-next'
Tom Herbert says:
====================
net: Checksum offload changes - Part V
I am working on overhauling RX checksum offload. Goals of this effort
are:
- Specify what exactly it means when driver returns CHECKSUM_UNNECESSARY
- Preserve CHECKSUM_COMPLETE through encapsulation layers
- Don't do skb_checksum more than once per packet
- Unify GRO and non-GRO csum verification as much as possible
- Unify the checksum functions (checksum_init)
- Simplify code
What is in this fifth patch set:
- Added GRO checksum validation functions
- Call the GRO validations functions from TCP and GRE gro_receive
- Perform checksum verification in the UDP gro_receive path using
GRO functions and add support for gro_receive in UDP6
Changes in V2:
- Change ip_summed to CHECKSUM_UNNECESSARY instead of moving it
to CHECKSUM_COMPLETE from GRO checksum validation. This avoids
performance penalty in checksumming bytes which are before the header
GRO is at.
Please review carefully and test if possible, mucking with basic
checksum functions is always a little precarious :-)
----
Test results with this patch set are below. I did not notice any
performace regression.
Tests run:
TCP_STREAM: super_netperf with 200 streams
TCP_RR: super_netperf with 200 streams and -r 1,1
Device bnx2x (10Gbps):
No GRE RSS hash (RX interrupts occur on one core)
UDP RSS port hashing enabled.
* GRE with checksum with IPv4 encapsulated packets
With fix:
TCP_STREAM
9.91% CPU utilization
5163.78 Mbps
TCP_RR
50.64% CPU utilization
219/347/502 90/95/99% latencies
834103 tps
Without fix:
TCP_STREAM
10.05% CPU utilization
5186.22 tps
TCP_RR
49.70% CPU utilization
227/338/486 90/95/99% latencies
813450 tps
* GRE without checksum with IPv4 encapsulated packets
With fix:
TCP_STREAM
10.18% CPU utilization
5159 Mbps
TCP_RR
51.86% CPU utilization
214/325/471 90/95/99% latencies
865943 tps
Without fix:
TCP_STREAM
10.26% CPU utilization
5307.87 Mbps
TCP_RR
50.59% CPU utilization
224/325/476 90/95/99% latencies
846429 tps
*** Simulate device returns CHECKSUM_COMPLETE
* VXLAN with checksum
With fix:
TCP_STREAM
13.03% CPU utilization
9093.9 Mbps
TCP_RR
95.96% CPU utilization
161/259/474 90/95/99% latencies
1.14806e+06 tps
Without fix:
TCP_STREAM
13.59% CPU utilization
9093.97 Mbps
TCP_RR
93.95% CPU utilization
160/259/484 90/95/99% latencies
1.10262e+06 tps
* VXLAN without checksum
With fix:
TCP_STREAM
13.28% CPU utilization
9093.87 Mbps
TCP_RR
95.04% CPU utilization
155/246/439 90/95/99% latencies
1.15e+06 tps
Without fix:
TCP_STREAM
13.37% CPU utilization
9178.45 Mbps
TCP_RR
93.74% CPU utilization
161/257/469 90/95/99% latencies
1.1068e+06 Mbps
====================
Signed-off-by: David S. Miller <davem@davemloft.net>