tun: support NAPI for packets received from batched XDP buffs
In tun, NAPI is supported and we can also use NAPI in the path of
batched XDP buffs to accelerate packet processing. What is more, after
we use NAPI, GRO is also supported. The iperf shows that the throughput of
single stream could be improved from 4.5Gbps to 9.2Gbps. Additionally, 9.2
Gbps nearly reachs the line speed of the phy nic and there is still about
15% idle cpu core remaining on the vhost thread.
Test topology:
[iperf server]<--->tap<--->dpdk testpmd<--->phy nic<--->[iperf client]
Iperf stream:
iperf3 -c 10.0.0.2 -i 1 -t 10
Before:
...
[ 5] 5.00-6.00 sec 558 MBytes 4.68 Gbits/sec 0 1.50 MBytes
[ 5] 6.00-7.00 sec 556 MBytes 4.67 Gbits/sec 1 1.35 MBytes
[ 5] 7.00-8.00 sec 556 MBytes 4.67 Gbits/sec 2 1.18 MBytes
[ 5] 8.00-9.00 sec 559 MBytes 4.69 Gbits/sec 0 1.48 MBytes
[ 5] 9.00-10.00 sec 556 MBytes 4.67 Gbits/sec 1 1.33 MBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.00 sec 5.39 GBytes 4.63 Gbits/sec 72 sender
[ 5] 0.00-10.04 sec 5.39 GBytes 4.61 Gbits/sec receiver
After:
...
[ 5] 5.00-6.00 sec 1.07 GBytes 9.19 Gbits/sec 0 1.55 MBytes
[ 5] 6.00-7.00 sec 1.08 GBytes 9.30 Gbits/sec 0 1.63 MBytes
[ 5] 7.00-8.00 sec 1.08 GBytes 9.25 Gbits/sec 0 1.72 MBytes
[ 5] 8.00-9.00 sec 1.08 GBytes 9.25 Gbits/sec 77 1.31 MBytes
[ 5] 9.00-10.00 sec 1.08 GBytes 9.24 Gbits/sec 0 1.48 MBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.00 sec 10.8 GBytes 9.28 Gbits/sec 166 sender
[ 5] 0.00-10.04 sec 10.8 GBytes 9.24 Gbits/sec receiver
Reported-at: https://lore.kernel.org/all/CACGkMEvTLG0Ayg+TtbN4q4pPW-ycgCCs3sC3-TF8cuRTf7Pp1A@mail.gmail.com
Signed-off-by: Harold Huang <baymaxhuang@gmail.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20220228033805.1579435-1-baymaxhuang@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
projects / kernel.git / commit