Re: [PATCH net-next v10 0/5] net: devmem: improve cpu cost of RX token management

Jakub Kicinski
2026-01-27T01:31:26Z

On Mon, 26 Jan 2026 10:45:22 -0800 Bobby Eshleman wrote:
> I'm onboard with improving what we have since it helps all of us
> currently using this API, though I'm not opposed to discussing a
> redesign in another thread/RFC. I do see the attraction to locating the
> core logic in one place and possibly reducing some complexity around
> socket/binding relationships.
>
> FWIW regarding nl, I do see it supports rtnl lock-free operations via
> '62256f98f244 rtnetlink: add RTNL_FLAG_DOIT_UNLOCKED' and routing was
> recently made lockless with that. I don't see / know of any fast path
> precedent. I'm aware there are some things I'm not sure about being
> relevant performance-wise, like hitting skb alloc an additional time
> every release batch. I'd want to do some minimal latency comparisons
> between that path and sockopt before diving head-first.

FTR I'm not really pushing Netlink specifically, it may work it
may not. Perhaps some other ioctl-y thing exists. Just in general
setsockopt() on a specific socket feels increasingly awkward for
buffer flow. Maybe y'all disagree.

I thought I'd clarify since I may be seen as "Mr Netlink Everywhere" :)