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Date: Thu, 9 Nov 2017 11:37:07 -0500 (EST)
From: Pankaj Gupta <pagupta@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>, Wanpeng Li <kernellwp@gmail.com>,
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Subject: Re: [PATCHv3 1/1] locking/qspinlock/x86: Avoid test-and-set when
 PV_DEDICATED is set
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Thread-Topic: locking/qspinlock/x86: Avoid test-and-set when PV_DEDICATED is set
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> Subject: Re: [PATCHv3 1/1] locking/qspinlock/x86: Avoid test-and-set when PV_DEDICATED is set
> 
> On Thu, Nov 09, 2017 at 05:05:36PM +0100, Radim Krcmar wrote:
> > 2017-11-09 10:53-0500, Pankaj Gupta:
> > > 2] PV TLB should also behave as per option PV_DEDICATED for better
> > > performance.
> > 
> > Right,
> 
> Shouldn't KVM do flush_tlb_other() in any case? Not sure how
> PV_DEDICATED can help with that.

Yes.

If I understand it correctly, It will just avoid traversing all the 
cpus another time just to check/set 'KVM_VCPU_PREEMPTED'/FLUSH value and 
clear the cpu mask.

Thanks,
Pankaj