Re: RT sched: cpupri_vec lock contention with def_root_domain and no load balance

[Max Krasnyansky <maxk@qualcomm.com>]

Gregory Haskins wrote:
> If you tried creating different cpusets and it still had them all end up
> in the def_root_domain, something is very broken indeed.  I will take a
> look.

I beleive that's the intended behaviour. We always put cpus that are not
balanced into null sched domains. This was done since day one (ie when
cpuisol= option was introduced) and cpusets just followed the same convention.

I think the idea is that we want to make balancer a noop on those processors.
We could change cpusets code to create a root sched domain for each cpu I
guess. But can we maybe scale cpupri some other way ?

Max