Merge branch 'ethtool-provide-the-dim-profile-fine-tuning-channel'

Heng Qi says:

====================
ethtool: provide the dim profile fine-tuning channel

The NetDIM library provides excellent acceleration for many modern
network cards. However, the default profiles of DIM limits its maximum
capabilities for different NICs, so providing a way which the NIC can
be custom configured is necessary.

Currently, the way is based on the commonly used "ethtool -C".

For example,
on the server side, the virtio-net NIC with rx dim enabled has 8
queues and runs nginx.
The client uses the following command to send traffic to the server:
  ./wrk http://server_ip:80 -c 64 -t 5 -d 30

Then adjust the default rx-profile for server dim to

  {.usec =   1, .pkts = 256, .comps = n/a,},
  {.usec =   8, .pkts = 256, .comps = n/a,},
  {.usec =  30, .pkts = 256, .comps = n/a,},
  {.usec =  64, .pkts = 256, .comps = n/a,},
  {.usec = 128, .pkts = 256, .comps = n/a,}

The server PPS is improved by 20%+.
====================

Link: https://patch.msgid.link/20240621101353.107425-1-hengqi@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>