Re: Requirements to control kernel isolation/nohz_full at runtime

From: Frederic Weisbecker
Date: Wed Sep 09 2020 - 18:39:02 EST


On Thu, Sep 03, 2020 at 03:52:00PM -0300, Marcelo Tosatti wrote:
> On Thu, Sep 03, 2020 at 02:36:36PM -0400, Phil Auld wrote:
> > exclusive cpusets is used now to control scheduler load balancing on
> > a group of cpus. It seems to me that this is the same idea and is part
> > of the isolation concept. Having a toggle for each subsystem/feature in
> > cpusets could provide the needed userspace api.
> >
> > Under the covers it might be implemented as twiddling various cpumasks.
> >
> > We need to be shifting to managing load balancing with cpusets anyway.
>
> OK, adding a new file per isolation feature:
>
> - cpuset.isolation_nohz_full
> - cpuset.isolation_kthread
> - cpuset.isolation_time
>
> With a bool value per file, is an option.

Exactly. I would merge kthread/timers/workqueue into
cpuset.isolation.unbound though. Unless anyone may need more
granularity there?