KVM: Implement NotifyLongSpinWait HYPER-V hypercall
Windows issues this hypercall after guest was spinning on a spinlock
for too many iterations.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Vadim Rozenfeld <vrozenfe@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 552be51..9f72a44 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1564,6 +1564,7 @@
case KVM_CAP_VCPU_EVENTS:
case KVM_CAP_HYPERV:
case KVM_CAP_HYPERV_VAPIC:
+ case KVM_CAP_HYPERV_SPIN:
r = 1;
break;
case KVM_CAP_COALESCED_MMIO:
@@ -3827,7 +3828,14 @@
trace_kvm_hv_hypercall(code, fast, rep_cnt, rep_idx, ingpa, outgpa);
- res = HV_STATUS_INVALID_HYPERCALL_CODE;
+ switch (code) {
+ case HV_X64_HV_NOTIFY_LONG_SPIN_WAIT:
+ kvm_vcpu_on_spin(vcpu);
+ break;
+ default:
+ res = HV_STATUS_INVALID_HYPERCALL_CODE;
+ break;
+ }
ret = res | (((u64)rep_done & 0xfff) << 32);
if (longmode) {
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 5ce6173..4c4937e 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -499,6 +499,7 @@
#define KVM_CAP_PPC_SEGSTATE 43
#define KVM_CAP_HYPERV 44
#define KVM_CAP_HYPERV_VAPIC 45
+#define KVM_CAP_HYPERV_SPIN 46
#ifdef KVM_CAP_IRQ_ROUTING