sched/idle: Move the cpuidle entry point to the generic idle loop

In order to integrate cpuidle with the scheduler, we must have a better
proximity in the core code with what cpuidle is doing and not delegate
such interaction to arch code.

Architectures implementing arch_cpu_idle() should simply enter
a cheap idle mode in the absence of a proper cpuidle driver.

In both cases i.e. whether it is a cpuidle driver or the default
arch_cpu_idle(), the calling convention expects IRQs to be disabled
on entry and enabled on exit. There is a warning in place already but
let's add a forced IRQ enable here as well.  This will allow for
removing the forced IRQ enable some implementations do locally and
allowing for the warning to trig.

Signed-off-by: Nicolas Pitre <[email protected]>
Acked-by: Daniel Lezcano <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Preeti U Murthy <[email protected]>
Cc: Paul Mundt <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: Olof Johansson <[email protected]>
Cc: Russell King <[email protected]>
Cc: Linus Torvalds <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

0 files changed, 0 insertions, 0 deletions