Merge branch 'net-rps-lockless'

Jason Xing says:

====================
locklessly protect left members in struct rps_dev_flow

From: Jason Xing <kernelxing@tencent.com>

Since Eric did a more complicated locklessly change to last_qtail
member[1] in struct rps_dev_flow, the left members are easier to change
as the same.

One thing important I would like to share by qooting Eric:
"rflow is located in rxqueue->rps_flow_table, it is thus private to current
thread. Only one cpu can service an RX queue at a time."
So we only pay attention to the reader in the rps_may_expire_flow() and
writer in the set_rps_cpu(). They are in the two different contexts.

[1]:
https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=3b4cf29bdab

v3
Link: https://lore.kernel.org/all/20240417062721.45652-1-kerneljasonxing@gmail.com/
1. adjust the protection in a right way (Eric)

v2
1. fix passing wrong type qtail.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>