mbox series

[net-next,0/5] virtio-net: make the virtio-net has independent directory

Message ID 20240116062842.67874-1-xuanzhuo@linux.alibaba.com (mailing list archive)
Headers show
Series virtio-net: make the virtio-net has independent directory | expand

Message

Xuan Zhuo Jan. 16, 2024, 6:28 a.m. UTC
This is first part of virtio-net support AF_XDP zero copy.

The whole patch set
http://lore.kernel.org/all/20231229073108.57778-1-xuanzhuo@linux.alibaba.com


## AF_XDP

XDP socket(AF_XDP) is an excellent bypass kernel network framework. The zero
copy feature of xsk (XDP socket) needs to be supported by the driver. The
performance of zero copy is very good. mlx5 and intel ixgbe already support
this feature, This patch set allows virtio-net to support xsk's zerocopy xmit
feature.

At present, we have completed some preparation:

1. vq-reset (virtio spec and kernel code)
2. virtio-core premapped dma
3. virtio-net xdp refactor

So it is time for Virtio-Net to complete the support for the XDP Socket
Zerocopy.

Virtio-net can not increase the queue num at will, so xsk shares the queue with
kernel.

On the other hand, Virtio-Net does not support generate interrupt from driver
manually, so when we wakeup tx xmit, we used some tips. If the CPU run by TX
NAPI last time is other CPUs, use IPI to wake up NAPI on the remote CPU. If it
is also the local CPU, then we wake up napi directly.

This patch set includes some refactor to the virtio-net to let that to support
AF_XDP.

## performance

ENV: Qemu with vhost-user(polling mode).
Host CPU: Intel(R) Xeon(R) Platinum 8163 CPU @ 2.50GHz

### virtio PMD in guest with testpmd

testpmd> show port stats all

 ######################## NIC statistics for port 0 ########################
 RX-packets: 19531092064 RX-missed: 0     RX-bytes: 1093741155584
 RX-errors: 0
 RX-nombuf: 0
 TX-packets: 5959955552 TX-errors: 0     TX-bytes: 371030645664


 Throughput (since last show)
 Rx-pps:   8861574     Rx-bps:  3969985208
 Tx-pps:   8861493     Tx-bps:  3969962736
 ############################################################################

### AF_XDP PMD in guest with testpmd

testpmd> show port stats all

  ######################## NIC statistics for port 0  ########################
  RX-packets: 68152727   RX-missed: 0          RX-bytes:  3816552712
  RX-errors: 0
  RX-nombuf:  0
  TX-packets: 68114967   TX-errors: 33216      TX-bytes:  3814438152

  Throughput (since last show)
  Rx-pps:      6333196          Rx-bps:   2837272088
  Tx-pps:      6333227          Tx-bps:   2837285936
  ############################################################################

But AF_XDP consumes more CPU for tx and rx napi(100% and 86%).

## maintain

I am currently a reviewer for virtio-net. I commit to maintain AF_XDP support in
virtio-net.

Please review.

Thanks.

Xuan Zhuo (5):
  virtio_net: rename free_old_xmit_skbs to free_old_xmit
  virtio_net: unify the code for recycling the xmit ptr
  virtio_net: independent directory
  virtio_net: move core structures to virtio_net.h
  virtio_net: add prefix virtnet to all struct inside virtio_net.h

 MAINTAINERS                                 |   2 +-
 drivers/net/Kconfig                         |   9 +-
 drivers/net/Makefile                        |   2 +-
 drivers/net/virtio/Kconfig                  |  12 +
 drivers/net/virtio/Makefile                 |   8 +
 drivers/net/{virtio_net.c => virtio/main.c} | 381 +++++---------------
 drivers/net/virtio/virtio_net.h             | 207 +++++++++++
 7 files changed, 316 insertions(+), 305 deletions(-)
 create mode 100644 drivers/net/virtio/Kconfig
 create mode 100644 drivers/net/virtio/Makefile
 rename drivers/net/{virtio_net.c => virtio/main.c} (94%)
 create mode 100644 drivers/net/virtio/virtio_net.h

--
2.32.0.3.g01195cf9f

Comments

Paolo Abeni Jan. 16, 2024, 12:32 p.m. UTC | #1
On Tue, 2024-01-16 at 14:28 +0800, Xuan Zhuo wrote:
> This is first part of virtio-net support AF_XDP zero copy.

For future submissions, unless explcitly requested otherwise, please
wait for a series being processed before posting the follow-ups.
Otherwise any change requested to earlier patches could possibly/likely
need changing  (and reposting) all the following.

> 
> The whole patch set
> http://lore.kernel.org/all/20231229073108.57778-1-xuanzhuo@linux.alibaba.com
> 
> 
> ## AF_XDP
> 
> XDP socket(AF_XDP) is an excellent bypass kernel network framework. The zero
> copy feature of xsk (XDP socket) needs to be supported by the driver. The
> performance of zero copy is very good. mlx5 and intel ixgbe already support
> this feature, This patch set allows virtio-net to support xsk's zerocopy xmit
> feature.
> 
> At present, we have completed some preparation:
> 
> 1. vq-reset (virtio spec and kernel code)
> 2. virtio-core premapped dma
> 3. virtio-net xdp refactor
> 
> So it is time for Virtio-Net to complete the support for the XDP Socket
> Zerocopy.
> 
> Virtio-net can not increase the queue num at will, so xsk shares the queue with
> kernel.
> 
> On the other hand, Virtio-Net does not support generate interrupt from driver
> manually, so when we wakeup tx xmit, we used some tips. If the CPU run by TX
> NAPI last time is other CPUs, use IPI to wake up NAPI on the remote CPU. If it
> is also the local CPU, then we wake up napi directly.
> 
> This patch set includes some refactor to the virtio-net to let that to support
> AF_XDP.
> 
> ## performance
> 
> ENV: Qemu with vhost-user(polling mode).
> Host CPU: Intel(R) Xeon(R) Platinum 8163 CPU @ 2.50GHz
> 
> ### virtio PMD in guest with testpmd
> 
> testpmd> show port stats all
> 
>  ######################## NIC statistics for port 0 ########################
>  RX-packets: 19531092064 RX-missed: 0     RX-bytes: 1093741155584
>  RX-errors: 0
>  RX-nombuf: 0
>  TX-packets: 5959955552 TX-errors: 0     TX-bytes: 371030645664
> 
> 
>  Throughput (since last show)
>  Rx-pps:   8861574     Rx-bps:  3969985208
>  Tx-pps:   8861493     Tx-bps:  3969962736
>  ############################################################################
> 
> ### AF_XDP PMD in guest with testpmd
> 
> testpmd> show port stats all
> 
>   ######################## NIC statistics for port 0  ########################
>   RX-packets: 68152727   RX-missed: 0          RX-bytes:  3816552712
>   RX-errors: 0
>   RX-nombuf:  0
>   TX-packets: 68114967   TX-errors: 33216      TX-bytes:  3814438152
> 
>   Throughput (since last show)
>   Rx-pps:      6333196          Rx-bps:   2837272088
>   Tx-pps:      6333227          Tx-bps:   2837285936
>   ############################################################################
> 
> But AF_XDP consumes more CPU for tx and rx napi(100% and 86%).
> 
> ## maintain
> 
> I am currently a reviewer for virtio-net. I commit to maintain AF_XDP support in
> virtio-net.
> 
> Please review.
> 
> Thanks.

## Form letter - net-next-closed

The merge window for v6.8 has begun and we have already posted our pull
request. Therefore net-next is closed for new drivers, features, code
refactoring and optimizations. We are currently accepting bug fixes
only.

Please repost when net-next reopens after January 22nd.

RFC patches sent for review only are obviously welcome at any time.

See:
https://www.kernel.org/doc/html/next/process/maintainer-netdev.html#development-cycle
--
pw-bot: defer