Currently, there are two major issues with stmmac driver statistics
First of all, statistics in stmmac_extra_stats, stmmac_rxq_stats
and stmmac_txq_stats are 32 bit variables on 32 bit platforms. This
can cause some stats to overflow after several minutes of
high traffic, for example rx_pkt_n, tx_pkt_n and so on.

Secondly, if HW supports multiqueues, there are frequent cacheline
ping pongs on some driver statistic vars, for example, normal_irq_n,
tx_pkt_n and so on. What's more, frequent cacheline ping pongs on
normal_irq_n happens in ISR, this makes the situation worse.

To improve the driver, we convert those statistics to 64 bit, implement
ndo_get_stats64 and update .get_ethtool_stats implementation
accordingly. We also use per-queue statistics where necessary to remove
the cacheline ping pongs as much as possible to make multiqueue
operations faster. Those statistics which are not possible to overflow
and not frequently updated are kept as is.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Link: https://lore.kernel.org/r/20230717160630.1892-3-jszhang@kernel.orgSigned-off-by: Jakub Kicinski <kuba@kernel.org>