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> > + > > I was originally thinking about reusing scx_builtin_idle_enabled here, > apologies if I wasn't clear enough. > > My reasoning is: If the user is doing their own idle CPU tracking, > in which case scx_builtin_idle_enable will be disabled, what's the point > of SCX tracking idle CPUs? > > Do you see a scenario where using one static branch is problematic? I think you're right, I added a separate key because __scx_update_idle() also delivers ops.update_idle() callbacks, but we can retain the existing scx_enabled() check for that case and use scx_builtin_idle_enabled only for early tracking. So I don't see any reason to add a separate static key. I'll rework this in v3. Thanks, -Andrea