Re: CONFIG_ISOLATION=y (was: [PATCH 0/6] support "dataplane" mode for nohz_full)

On Tue, May 12, 2015 at 11:10:32AM +0200, Ingo Molnar wrote:

So I'd vote for Frederic's CONFIG_ISOLATION=y, mostly because this is 
a high level kernel feature, so it won't conflict with isolation 
concepts in lower level subsystems such as IOMMU isolation - and other 
higher level features like scheduler isolation are basically another 
partial implementation we want to merge with all this...

But why do we need a CONFIG flag for something that has no content?

That is, I do not see anything much; except the 'I want to stay in
userspace and kill me otherwise' flag, and I'm not sure that warrants a
CONFIG flag like this.

Other than that, its all a combination of NOHZ_FULL and cpusets/isolcpus
and whatnot.