Re: [PATCH 4/4] nohz: Set isolcpus when nohz_full is set

Mike Galbraith
2015-05-18T03:29:26Z

On Sun, 2015-05-17 at 22:17 -0400, Rik van Riel wrote:
> On 05/17/2015 01:30 AM, Mike Galbraith wrote:
>
> > Given that kernel initiated association to isolcpus, a user turning
> > NO_HZ_FULL_ALL on had better not have much generic load to manage. If
> > he/she does not have CPUSETS enabled, or should Rik's patch rendering
> > isolcpus immutable be merged,
>
> My patch does not aim to make isolcpus immutable, it aims to make
> isolcpus resistent to system management tools (like libvirt)
> automatically undoing isolcpus the instant a cpuset with the default
> cpus (inherited from the root group) is created.

Aim or not, if cpusets is the sole modifier, it'll render isolcpus
immutable, no? Cpusets could grow an override to the override I
suppose, to regain control of the resource it thinks it manages.

-Mike