Re: [PATCH 1/7] sched: Add static_key for asymmetric cpu capacity optimizations

[Morten Rasmussen]

On Fri, Feb 16, 2018 at 05:51:23PM +0100, Peter Zijlstra wrote:
> On Fri, Feb 16, 2018 at 03:41:01PM +0000, Morten Rasmussen wrote:
> > On Fri, Feb 16, 2018 at 02:47:04PM +0100, Peter Zijlstra wrote:
> > > ? possibly with:
> > > 
> > > 	else
> > > 		static_branch_disable(&sched_asym_cpucapacity);
> > > 
> > > if you want to play funny games :-)
> > 
> > I thought about that too. It could make certain hotplug scenarios even
> > more expensive. I think we want the sched_asym_cpucapacity code to behave
> > even if SD_ASYM_CPUCAPACITY isn't set anywhere, so the static key would
> > be permanently from the point we detect asymmetry and leave it set. This
> > would be in line with how the smt static key works.
> 
> Fair enough..

Yeah, we can always add the 'else' bit later if we find a good reason to
do so.