KVM: In kernel PIT model
The patch moves the PIT model from userspace to kernel, and increases
the timer accuracy greatly.
[marcelo: make last_injected_time per-guest]
Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Tested-and-Acked-by: Alex Davis <alex14641@yahoo.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index bf78d65..c33a457 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -17,6 +17,7 @@
#include <linux/kvm_host.h>
#include "irq.h"
#include "mmu.h"
+#include "i8254.h"
#include <linux/clocksource.h>
#include <linux/kvm.h>
@@ -818,6 +819,7 @@
case KVM_CAP_SET_TSS_ADDR:
case KVM_CAP_EXT_CPUID:
case KVM_CAP_CLOCKSOURCE:
+ case KVM_CAP_PIT:
r = 1;
break;
case KVM_CAP_VAPIC:
@@ -1594,6 +1596,12 @@
} else
goto out;
break;
+ case KVM_CREATE_PIT:
+ r = -ENOMEM;
+ kvm->arch.vpit = kvm_create_pit(kvm);
+ if (kvm->arch.vpit)
+ r = 0;
+ break;
case KVM_IRQ_LINE: {
struct kvm_irq_level irq_event;
@@ -3372,6 +3380,7 @@
void kvm_arch_destroy_vm(struct kvm *kvm)
{
+ kvm_free_pit(kvm);
kfree(kvm->arch.vpic);
kfree(kvm->arch.vioapic);
kvm_free_vcpus(kvm);