The patch adds guest code for msr between guest and hypervisor. The
msr will export the vcpu running/pre-empted information to the guest
from host. This will enable guest to intelligently send ipi to running
vcpus and set flag for pre-empted vcpus. This will prevent waiting for
vcpus that are not running.
Suggested-by: Peter Zijlstra<a.p.zijlstra@xxxxxxxxx>
Signed-off-by: Nikunj A. Dadhania<nikunj@xxxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/kvm_para.h | 10 ++++++++++
arch/x86/kernel/kvm.c | 33 +++++++++++++++++++++++++++++++++
2 files changed, 43 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h
index 77266d3..f57b5cc 100644
--- a/arch/x86/include/asm/kvm_para.h
+++ b/arch/x86/include/asm/kvm_para.h
@@ -24,6 +24,7 @@
#define KVM_FEATURE_ASYNC_PF 4
#define KVM_FEATURE_STEAL_TIME 5
#define KVM_FEATURE_PV_UNHALT 6
+#define KVM_FEATURE_VCPU_STATE 7