Re: [PATCH 0/6] x86/cpu hotplug: Wake up offline CPU via mwait or nmi

[Andi Kleen]

Thomas Gleixner <tglx@xxxxxxxxxxxxx> writes:
>
> 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.

Why not? I think the kernel is exactly the right place for it.
It's essentially a scheduling problem. Scheduling in user space
is not a good idea.

With MSI-X the drivers just want a static setting. User space
shouldn't mess with it. 

Some of the workarounds for user space messing with it (like that
interrupt rmap code) are really bad and just a workaround for doing the
scheduling in the wrong place.

For dynamic changes it should indeed by part of scheduling,
following similar rules, with only high level policy input
from userland.

-Andi

-- 
ak@xxxxxxxxxxxxxxx -- Speaking for myself only
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