Re: [PATCH RFC] cpuset: Make cpusets get restored on hotplug

From: Tejun Heo
Date: Thu Mar 26 2020 - 15:20:41 EST


On Thu, Mar 26, 2020 at 03:16:23PM -0400, Joel Fernandes (Google) wrote:
> This deliberately changes the behavior of the per-cpuset
> cpus file to not be effected by hotplug. When a cpu is offlined,
> it will be removed from the cpuset/cpus file. When a cpu is onlined,
> if the cpuset originally requested that that cpu was part of the cpuset,
> that cpu will be restored to the cpuset. The cpus files still
> have to be hierachical, but the ranges no longer have to be out of
> the currently online cpus, just the physically present cpus.

This is already the behavior on cgroup2 and I don't think we want to
introduce this big a behavior change to cgroup1 cpuset at this point.

Thanks.

--
tejun