Re: [PATCH net-next v2 0/4] netconsole: Optimize console registration and improve testing

[Jakub Kicinski]

On Mon, 02 Jun 2025 03:34:40 -0700 Breno Leitao wrote:
> During performance analysis of console subsystem latency, I discovered that
> netconsole registers console handlers even when no active targets exist.
> These orphaned console handlers are invoked on every printk() call, get
> the lock, iterate through empty target lists, and consume CPU cycles
> without performing any useful work.
> 
> This patch series addresses the inefficiency by:
> 
> 1. Implementing dynamic console registration/unregistration based on target
>    availability, ensuring console handlers are only active when needed
> 2. Adding automatic cleanup of unused console registrations when targets
>    are disabled or removed
> 3. Extending the selftest suite to cover non-extended console format,
>    which was previously untested
> 
> The optimization reduces printk() overhead by eliminating unnecessary
> function calls and list traversals when netconsole targets are not
> configured, improving overall system performance during heavy logging
> scenarios.

Ah, I wasn't very clear, full form letter at the end.

But also the tests seem to have failed now:
https://netdev.bots.linux.dev/contest.html?branch=net-next-2025-06-02--12-00&executor=vmksft-net-drv&pw-n=0&pass=0


## Form letter - net-next-closed

Linus has already merged our PR with features for v6.16.
net-next is closed for new drivers, features, code refactoring and
optimizations for the remained for the merge window.

Please repost when net-next reopens after June 9th.

RFC patches sent for review only are obviously welcome at any time.

See:
https://www.kernel.org/doc/html/next/process/maintainer-netdev.html#development-cycle
-- 
pw-bot: defer
pv-bot: closed