Hi Dimitri, On 29/09/15 18:00, Dimitri John Ledkov wrote: > From: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx> > > with the TSC deadline timer feature, we don't need to calibrate the apic > timers anymore, which saves more than 100 milliseconds of boot time. > > Signed-off-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx> > Signed-off-by: Dimitri John Ledkov <dimitri.j.ledkov@xxxxxxxxx> > --- > x86/cpuid.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/x86/cpuid.c b/x86/cpuid.c > index c3b67d9..1d8bd23 100644 > --- a/x86/cpuid.c > +++ b/x86/cpuid.c > @@ -31,6 +31,9 @@ static void filter_cpuid(struct kvm_cpuid2 *kvm_cpuid) > /* Set X86_FEATURE_HYPERVISOR */ > if (entry->index == 0) > entry->ecx |= (1 << 31); > + /* Set CPUID_EXT_TSC_DEADLINE_TIMER*/ > + if (entry->index == 0) > + entry->ecx |= (1 << 24); This can only be enabled if the kernel supports emulation of that feature (reported via KVM_CAP_TSC_DEADLINE_TIMER) (cf: Documentation/virtual/kvm/api.txt and respective QEMU code in target-i386/kvm.c) Cheers, Andre. > break; > case 6: > /* Clear X86_FEATURE_EPB */ > -- 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
