Merge branch 'for-io_uring-add-napi-busy-polling-support'

Merge netdev bits of io_uring busy polling support.

Jens Axboe says:

====================
io_uring: add napi busy polling support

I finally got around to testing this patchset in its current form, and
results look fine to me. It Works. Using the basic ping/pong test that's
part of the liburing addition, without enabling NAPI I get:

Stock settings, no NAPI, 100k packets:

 rtt(us) min/avg/max/mdev = 31.730/37.006/87.960/0.497

 and with -t10 -b enabled:

 rtt(us) min/avg/max/mdev = 23.250/29.795/63.511/1.203

In short, this patchset enables per io_uring NAPI enablement, rather
than need to enable that globally. This allows targeted NAPI usage with
io_uring.

Here's Stefan's v15 posting, which predates this one:

https://lore.kernel.org/io-uring/20230608163839.2891748-1-shr@devkernel.io/
====================

Link: https://lore.kernel.org/r/20240206163422.646218-1-axboe@kernel.dk


Signed-off-by: Jakub Kicinski <kuba@kernel.org>