Re: [PATCH v4 0/4] Introduce Per-CPU Work helpers (was QPW)

[Sebastian Andrzej Siewior]

On 2026-07-13 18:17:23 [-0300], Leonardo Bras wrote:
> IIRC there are multiple users of this mechanism around the kernel. I 
> remember picking the first three (swap, slub and memcontrol) as examples of 
> how to use pwlocks (QPW at the time). With the concept proven, I could then 
> proceed to work with other potential users to replace it. (We ended up 
> dropping memcontrol in the process)
> 
> The main idea is to replace as many potential users as possible to reduce 
> as much as possible the amount of IPIs in isolated cpus, and allow Linux 
> to run workloads which require much lower latency.

Right. I am not entirely opposed to this idea. If you can't improve the
situation by other means I would consider this as the last resort. If
the mm folks are on board with this, then even better.

> This idea came as a general solution to a bunch of latency violations  
> Marcelo and I were coming across.
> 
> Thanks!
> Leo

Sebastian