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Date:   Mon, 25 Jan 2021 08:46:20 +0000
From:   Marc Zyngier <maz@kernel.org>
To:     Alex Shi <alex.shi@linux.alibaba.com>
Cc:     Sean Christopherson <seanjc@google.com>,
        Paolo Bonzini <pbonzini@redhat.com>, kvm@vger.kernel.org,
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Subject: Re: 3 preempted variables in kvm
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On 2021-01-25 05:49, Alex Shi wrote:
> Hi Sean,
> 
> Thanks a lot for the detailed explanations.
> Yes, they are all meaningful variables on x86. But for more archs,
> guess the lock
> issue on different arch's guest are similar. Maybe a abstraction on
> the point would
> be very helpful. Any comments?

It depends on what you have in mind. The whole "yield to another
vcpu" mechanism is already abstracted behind kvm_vcpu_on_spin(),
which at arm64, s390 and x86 are using. You could investigate
whether this is a valid approach for Power and MIPS.

Thanks,

         M.
-- 
Jazz is not dead. It just smells funny...