Most windows guests which I have on hand currently still utilize APIC Timer periodic/oneshot mode instead of APIC Timer tsc-deadline mode: - windows 2008 server r2 - windows 2012 server r2 - windows 7 - windows 10 This patchset adds the support using the VMX preemption timer for APIC Timer periodic/oneshot mode. I add periodic mode testcase to kvm-unit-tests/apic.flat and observed that w/ patch the latency is ~13% of w/o patch. I think maybe something is still not right in the patchset. Your comments to improve the patchset is a great appreciated. v1 -> v2: * remember the timeout when setting up the timer to get a correct TMCCT * move apic->lapic_timer.period/tscdeadline caculations to start_apic_timer() Wanpeng Li (2): KVM: lapic: introduce start_sw_period() to handle oneshot/periodic mode KVM: x86: Support using the VMX preemption timer for APIC Timer periodic/oneshot mode arch/x86/kvm/lapic.c | 166 ++++++++++++++++++++++++++++++++------------------- arch/x86/kvm/lapic.h | 1 + 2 files changed, 107 insertions(+), 60 deletions(-) -- 1.9.1 -- 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
