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>

2 files changed, 3 insertions, 0 deletions

diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h
index 49ced21e0290..26a313a09472 100644
--- a/include/asm-x86/kvm_host.h
+++ b/include/asm-x86/kvm_host.h
@@ -298,6 +298,7 @@ struct kvm_arch{
         struct list_head active_mmu_pages;
         struct kvm_pic *vpic;
         struct kvm_ioapic *vioapic;
+        struct kvm_pit *vpit;
 
         int round_robin_prev_vcpu;
         unsigned int tss_addr;
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index e92e70324ea1..cefa9a2c7b89 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -236,6 +236,7 @@ struct kvm_vapic_addr {
 #define KVM_CAP_CLOCKSOURCE 8
 #define KVM_CAP_NR_VCPUS 9       /* returns max vcpus per vm */
 #define KVM_CAP_NR_MEMSLOTS 10   /* returns max memory slots per vm */
+#define KVM_CAP_PIT 11
 
 /*
  * ioctls for VM fds
@@ -258,6 +259,7 @@ struct kvm_vapic_addr {
 #define KVM_IRQ_LINE              _IOW(KVMIO, 0x61, struct kvm_irq_level)
 #define KVM_GET_IRQCHIP           _IOWR(KVMIO, 0x62, struct kvm_irqchip)
 #define KVM_SET_IRQCHIP           _IOR(KVMIO,  0x63, struct kvm_irqchip)
+#define KVM_CREATE_PIT            _IO(KVMIO,  0x64)
 
 /*
  * ioctls for vcpu fds