On Tue, May 12, 2020 at 6:26 PM Quentin Perret <[email protected]> wrote: > > On Tuesday 12 May 2020 at 17:30:36 (+0200), Rafael J. Wysocki wrote: > > On Tue, May 12, 2020 at 5:11 PM Quentin Perret <[email protected]> wrote: > > > The end goal with GKI is the following: Google will release a single > > > binary kernel image (signed, etc etc) that all devices using a given > > > Android version will be required to use. That image is however going to > > > be only for the core of the kernel (no drivers or anything of the sort). > > > Vendors and OEMs, on their end, will be responsible to build and ship > > > GKI-compatible modules for their respective devices. So, Android devices > > > will eventually ship with a Google-issued GKI, plus a bunch of > > > vendor-provided modules loaded during boot. > > > > If that is the case, then I absolutely think that schedutil should be > > part of the GKI. > > > > Moreover, that would have been my opinion even if it had been modular > > in the first place. > > I definitely understand the feeling. Heck I contributed to schedutil, so > I'd love to see the entire world run it :-) > > But my personal preference doesn't seem to matter in this world, sadly. > The truth is, we cannot afford to be arbitrary in our decisions in GKI. > Switching governors and such is a fully supported feature upstream, and > it has been for a long time. Taking that away from partners is not the > goal, nor the intention, of GKI.
It still will be possible with schedutil built-in, however. > They will be able to choose whatever > governor they want, because there are no *objective* reasons to not let > them do that. Which, again, is still possible with non-modular schedutil AFAICS. I don't see any technical reason for making schedutil modular in the context of GKI other than to make the GKI image smaller, but I don't expect that to be significant enough. Is there anything else I am missing? > > > This is a significant shift from the current model where vendors > > > completely own the kernel, and are largely free to use the kernel config > > > they want. Today, those who don't use schedutil are free to turn the > > > config off, for example. > > > > So why is this regarded as a good thing? > > You mean using something else than schedutil? I mean why allowing people to compile schedutil out is regarded as a good thing. > It is not seen as a good > thing at all, at least not by me. But we have the same problem as > upstream. We cannot remove the other governors or the governor API for a > simple reason: they have users :/ I'm not saying about removing any of that. I'm just trying to understand why you need schedutil to be modular so as to make those things possible. Cheers!
