Messages in this thread |  | | | Date | Fri, 10 Jul 2009 15:56:18 +0200 | | From | Ingo Molnar <> | | Subject | Re: [PATCH] enable x2APIC without interrupt remapping under KVM |
* Gleb Natapov <gleb@redhat.com> wrote:
> KVM would like to provide x2APIC interface to a guest without emulating > interrupt remapping device. The reason KVM prefers guest to use x2APIC > is that x2APIC interface is better virtualizable and provides better > performance than mmio xAPIC interface: > > - msr exits are faster than mmio (no page table walk, emulation) > - no need to read back ICR to look at the busy bit > - one 64 bit ICR write instead of two 32 bit writes > - shared code with the Hyper-V paravirt interface > > Included patch changes x2APIC enabling logic to enable it even if IR > initialization failed, but kernel runs under KVM and no apic id is > greater than 255 (if there is one spec requires BIOS to move to x2apic > mode before starting an OS). > > Signed-off-by: Gleb Natapov <gleb@redhat.com> > Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> > --- > > This is the same as v5 only rebased on x86 tree (a74d2cea).
Looks good.
Small detail: please run the patch through scripts/checkpatch.pl and fix the complaints it has - all 3 details it points out seem like valid complaints to me (at a quick glance) that should be fixed.
Thanks,
Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |