[PATCH v5 0/6] Use eoi to track RTC interrupt delivery status

[Yang Zhang <yang.z.zhang@intel.com>]

From: Yang Zhang <yang.z.zhang@Intel.com>

Current interrupt coalescing logci which only used by RTC has conflict
with Posted Interrupt.

This patch introduces a new mechinism to use eoi to track interrupt:
When delivering an interrupt to vcpu, the pending_eoi set to number of
vcpu that received the interrupt. And decrease it when each vcpu writing
eoi. No subsequent RTC interrupt can deliver to vcpu until all vcpus
write eoi.

Changes from v4 to v5
* Calculate destination vcpu on interrupt injection not hook into ioapic 
  modification.
* Rebase on top of KVM.

Changes from v3 to v4
* Call kvm_apic_match_dest() to check destination vcpu.
* Update RTC interrrupt's destination vcpu map when ioapic entry of RTC
  or apic register (id, ldr, dfr) is changed.

Changes from v2 to v3:
* Remove unused viarable irq_ack_notifier.
* Acquire ioapic->lock before calculte destination vcpu map.
* Copy vcpu_map to expected_eoi_timap on each RTC irq and clear it on eoi.

Yang Zhang (6):
  KVM: Add vcpu info to ioapic_update_eoi()
  KVM: Introduce struct rtc_status
  KVM : Return destination vcpu on interrupt injection
  KVM: Add reset/restore rtc_status support
  KVM : Force vmexit with virtual interrupt delivery
  KVM: Use eoi to track RTC interrupt delivery status

 arch/x86/kvm/lapic.c |   31 ++++++++++++---
 arch/x86/kvm/lapic.h |    7 ++-
 virt/kvm/ioapic.c    |  103 ++++++++++++++++++++++++++++++++++++++++++++++----
 virt/kvm/ioapic.h    |   13 +++++-
 virt/kvm/irq_comm.c  |   12 +++---
 5 files changed, 142 insertions(+), 24 deletions(-)