Re: [PATCH 01/18] Make TSC offset writes non-preemptible

Avi Kivity
2010-07-18T14:30:40Z

On 07/13/2010 05:25 AM, Zachary Amsden wrote:
>
> +void guest_write_tsc(struct kvm_vcpu *vcpu, u64 data)
> +{
> + struct kvm *kvm = vcpu->kvm;
> + u64 offset;
> +
> + spin_lock(&kvm->arch.tsc_write_lock);
>

Perhaps spin_lock_irq() for even more accuracy?

spin_lock_irq_nmi_smi_hypervisor(), if you can find it.

> + offset = data - native_read_tsc();
> + kvm_x86_ops->write_tsc_offset(vcpu, offset);
> + spin_unlock(&kvm->arch.tsc_write_lock);
> +
> + /* Reset of TSC must disable overshoot protection below */
> + vcpu->arch.hv_clock.tsc_timestamp = 0;
> +}
> +EXPORT_SYMBOL_GPL(guest_write_tsc);
> +
>

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