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    SubjectRe: [PATCH v2 4/6] KVM-GST: KVM Steal time registration
    On 01/28/2011 09:52 PM, Glauber Costa wrote:
    > Register steal time within KVM. Everytime we sample the steal time
    > information, we update a local variable that tells what was the
    > last time read. We then account the difference.
    >
    >
    >
    > static void kvm_guest_cpu_offline(void *dummy)
    > {
    > kvm_pv_disable_apf(NULL);
    > + native_write_msr(MSR_KVM_STEAL_TIME, 0, 0);
    > apf_task_wake_all();
    > }

    Don't use the native_ versions, they override the pvops implementation.
    It doesn't matter for kvm, but we're not supposed to know this.

    > + /*
    > + * using nanoseconds introduces noise, which accumulates easily
    > + * leading to big steal time values. We want, however, to keep the
    > + * interface nanosecond-based for future-proofness. The hypervisor may
    > + * adopt a similar strategy, but we can't rely on that.
    > + */
    > + delta /= NSEC_PER_MSEC;
    > + delta *= NSEC_PER_MSEC;

    You're working around this problem both in the guest and host. So even
    if we fix it in one, it will still be broken in the other.

    > +
    > + return delta;
    > +}
    > +

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



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