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Date: Tue, 14 Nov 2017 08:35:39 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Wanpeng Li <kernellwp@gmail.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        kvm <kvm@vger.kernel.org>, Paolo Bonzini <pbonzini@redhat.com>,
        Radim Kr??m???? <rkrcmar@redhat.com>,
        Wanpeng Li <wanpeng.li@hotmail.com>
Subject: Re: [PATCH v4 2/4] KVM: X86: Add paravirt remote TLB flush
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On Tue, Nov 14, 2017 at 02:10:16PM +0800, Wanpeng Li wrote:
> 2017-11-13 21:02 GMT+08:00 Peter Zijlstra <peterz@infradead.org>:
> > That can be written like:
> >
> >         do {
> >                 if (state & KVM_VCPU_PREEMPTED)
> >                         new_state = state | KVM_VCPU_SHOULD_FLUSH;
> >                 else
> >                         new_state = state | KVM_VCPU_IPI_PENDING;
> >         } while (!try_cmpxchg(&src->preempted, state, new_state);
> >
> >         if (new_state & KVM_VCPU_IPI_PENDING)
> 
> Should be new_state & KVM_VCPU_SHOULD_FLUSH I think.

Quite so indeed.