UDP IPv6 Optimizations Queued Up For Linux 5.18

With Linux 5.17 are some nice networking performance optimizations touching different areas while the never-ending optimization work will continue with Linux 5.18.

The previously reported on patches providing a ~5% improvement for UDP/IPv6 is now queued in the networking subsystem's net-next codebase ahead of the Linux 5.18 merge window opening around the end of March.

That UDP IPv6 work is summed up in this merge:

Shed some weight from udp/ipv6. Zerocopy benchmarks over dummy showed ~5% tx/s improvement, should be similar for small payload non-[zero copy] cases.

The performance comes from killing 4 atomics and a couple of big struct memcpy/memset. 1/10 removes a pair of atomics on dst refcounting for cork->skb setup, 9/10 saves another pair on cork init. 5/10 and 8/10 kill extra 88B memset and memcpy respectively.

Linux 5.18 stable in turn should be out around the end of May with these optimization patches and a whole lot more.