Re: [PATCH 00/14] Modularize schedutil

[Peter Zijlstra]

On Fri, May 08, 2020 at 12:37:21PM +0200, Greg KH wrote:
> On Fri, May 08, 2020 at 10:11:28AM +0200, Peter Zijlstra wrote:
> > On Thu, May 07, 2020 at 07:09:58PM +0100, Quentin Perret wrote:
> > > One challenge to implement GKI is to avoid bloating the kernel by
> > > compiling too many things in, especially given that different devices
> > > need different things. As such, anything that can be turned into a
> > > module helps GKI, by offering an alternative to having that component
> > > built-in. This is true for pretty much anything that can be made
> > > modular, including drivers as well as other kernel components, such as
> > > CPUFreq governors.
> > 
> > The idea is to move to 1 governor, schedutil. Also, I abhor all the
> > exports this thing does. Modules have no business touching most of that.
> > 
> > Look at every EXPORT you do and wonder ask yourself how you can abuse
> > it. Modules are not a good thing, they're horrible pieces of crap.
> 
> Quentin, what is missing from schedutil that warrants the need for a
> totally different governor?  Is there specific problems with the
> existing ones or is this just an instance of "we wrote our own a long
> time ago and never pushed it upstream" from various SoC companies?

At the very least there's that interactive governor that's really
popular with Android. But IIRC there's a whole scala of home-brew
governors and tweaks out there.

And instead of enabling that crap, we should be discouraging it.
Consolidate and kill the governor interface.