Messages in this thread | | | Subject | RE: [PATCH 0/6] x86/cpu hotplug: Wake up offline CPU via mwait or nmi | From | Peter Zijlstra <> | Date | Tue, 05 Jun 2012 21:49:16 +0200 |
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On Tue, 2012-06-05 at 21:43 +0200, Thomas Gleixner wrote: > Vs. the interrupt/timer/other crap madness: > > - We really don't want to have an interrupt balancer in the kernel > again, but we need a mechanism to prevent the user space balancer > trainwreck from ruining the power saving party.
What's wrong with having an interrupt balancer tied to the scheduler which optimistically tries to avoid interrupting nohz/isolated/idle cpus?
> - The timer issue is mostly solved by the existing nohz stuff > (plus/minus the few bugs in there).
Its not.. if you create an isolated domain there's no way to expel existing timers from there.
> - The other details (silly IPIs) and cross CPU timer arming) are way > easier to solve by a proper prohibitive state than by chasing that > nonsense all over the tree forever.
But we need to solve all that without a prohibitibe state anyway for the isolation stuff to be useful.
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