Re: [RFC PATCH 4/4] cpuset: Support RCU-NOCB toggle on v2 root partitions
From: Peter Zijlstra
Date: Mon May 30 2022 - 09:16:46 EST
On Mon, May 30, 2022 at 12:56:50PM +0200, Frederic Weisbecker wrote:
> > This is ABI, you can't walk back on it. I would suggest starting with an
> > 'all feature' isolation. Only if there's real demand for something more
> > fine-grained add that on top. Simple first etc.
>
> That's actually my worry. If we start with an all in one ABI, how do we later
> mix that up with more finegrained features? Like what will be the behaviour of:
>
> cpuset.isolation.rcu_nocb = 0
> cpuset.isolation.all = 1
Well clearly that doesn't make sense. I was more thinking along the
lines of cgroup.subtree_control, where instead all features are enabled
by default.
But only if there's a real usecase, otherwise there's no point in
providing such knobs.