Re: [PATCHv2 2/9] KVM: Expose a version 2 architectural PMU to a guests

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, 2011-11-03 at 14:33 +0200, Gleb Natapov wrote:
> +static void kvm_perf_overflow_intr(struct perf_event *perf_event,
> +               struct perf_sample_data *data, struct pt_regs *regs)
> +{
> +       struct kvm_pmc *pmc = perf_event->overflow_handler_context;
> +       struct kvm_pmu *pmu = &pmc->vcpu->arch.pmu;
> +       if (!test_and_set_bit(pmc->idx, (unsigned long *)&pmu->reprogram_pmi)) {
> +               kvm_perf_overflow(perf_event, data, regs);
> +               kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
> +               /*
> +                * Inject PMI. If vcpu was in a guest mode during NMI PMI
> +                * can be ejected on a guest mode re-entry. Otherwise we can't
> +                * be sure that vcpu is not halted, so we should kick it, but
> +                * this is impossible from NMI context. Do it from irq work
> +                * instead.
> +                */
> +               if (!kvm_is_in_guest())
> +                       irq_work_queue(&pmc->vcpu->arch.pmu.irq_work);
> +               else
> +                       kvm_make_request(KVM_REQ_PMI, pmc->vcpu);
> +       }
> +} 

I'm not sure I get this, since the counters are vcpu task bound and only
count while the guest is running as per (144d31e6f19) how can we get an
NMI outside of guest context with the vcpu not halted?
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux