[PATCH] ethdev: document that stats reset APIs are not thread-safe

[Morten Brørup]

> From: Ferruh Yigit [mailto:ferruh.yigit at amd.com]
> Sent: Thursday, 25 April 2024 18.53
> 
> Making 'rte_eth_stats_reset()' and 'rte_eth_xstats_reset()' APIs thread
> safe has performance impact on datapath.
> 
> Instead document APIs as not thread safe and add condition for reliable
> stats reset functionality, forwarding should be stopped.

I'm not sure stopping forwarding suffices.
NIC hardware counters will keep progressing unless RX and TX is stopped at NIC level.

I don't have any suggestions for a better wording, though. :-(

Anyway, better with the patch than without...
Acked-by: Morten Brørup <mb at smartsharesystems.com>