sched/fair: Favor higher cpus only for boosted tasks
This CL separates the notion of boost and prefer_idle schedtune
attributes in cpu selection. Today only top-app
tasks are boosted. The CPU selection is slightly tweaked such that
higher order cpus are preferred only for boosted tasks (top-app) and the
rest would be skewed towards lower order cpus.
This avoids starvation issues for fg tasks when interacting with high
priority top-app tasks (a problem often seen in the case of system_server).
bug:
30245369
bug:
30292998
Change-Id: I0377e00893b9f6586eec55632a265518fd2fa8a1
Conflicts:
kernel/sched/fair.c