KVM: Avoid saving and restoring some host CPU state on lightweight vmexit
Many msrs and the like will only be used by the host if we schedule() or
return to userspace. Therefore, we avoid saving them if we handle the
exit within the kernel, and if a reschedule is not requested.
Based on a patch from Eddie Dong <eddie.dong@intel.com> with a couple of
fixes by me.
Signed-off-by: Yaozu(Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 8f1f07a..7d68258 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -72,6 +72,7 @@
{ "halt_exits", STAT_OFFSET(halt_exits) },
{ "request_irq", STAT_OFFSET(request_irq_exits) },
{ "irq_exits", STAT_OFFSET(irq_exits) },
+ { "light_exits", STAT_OFFSET(light_exits) },
{ NULL }
};