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Date: Thu, 02 Feb 2012 19:23:39 +0200
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Subject: Re: [v7 0/8] Reduce cross CPU IPI interference
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On 02/02/2012 07:01 PM, Paul E. McKenney wrote:
> > 
> > It's not called (since the cpu is not idle).  Instead we call
> > rcu_virt_note_context_switch().
>
> Frederic's work checks to see if there is only one runnable user task
> on a given CPU.  If there is only one, then the scheduling-clock interrupt
> is turned off for that CPU, and RCU is told to ignore it while it is
> executing in user space.  Not sure whether this covers KVM guests.

Conceptually it's the same.  Maybe it needs adjustments, since kvm
enters a guest in a different way than the kernel exits to userspace.

> In any case, this is not yet in mainline.

Let me know when it's in, and I'll have a look.

-- 
error compiling committee.c: too many arguments to function