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    SubjectRe: [RESEND 2][PATCH 4/4] Modify KVM to update guest time accounting.
    Laurent Vivier wrote:



    >> But if we didn't get an interrupt in that time?
    >>
    >> We can clear it a bit later, after local_irq_enable() in __vcpu_run().
    >> However we need a nop instruction first because "sti" keeps interrupts
    >> disabled for one more instruction.
    >>
    >
    > IMHO, I think it is better to let kvm_guest_exit() empty (you can remove it, if
    > you want):
    >
    > 1st case:
    > - unset PF_VCPU in kvm_guest_exit(), all the tick is always for system time.
    > Guest time is always 0.
    >
    > 1st case and half:
    >
    > - like 1st case but we move kvm_guest_exit() as you propose and the reason of
    > the interrupt is the tick interrupt. The tick is for guest time only. I think
    > the probability is very low.
    >

    If the guest is executing for 10% of the time, the probability is
    exactly 10%, no?

    > 2nd case:
    > - don't unset PF_VCPU in kvm_guest_exit(), all the tick is for guest time.
    >

    But then even execution in ->handle_exit() is accounted as guest time,
    which is wrong.



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

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