From 785dbef407d8b3c82348aba2689e493c752c62ec Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Thu, 16 Apr 2015 16:58:22 +0200 Subject: [PATCH] KVM: s390: optimize round trip time in request handling The fast path for a sie exit is that no kvm reqest is pending. Make an early check to skip all single bit checks. Reviewed-by: David Hildenbrand Signed-off-by: Christian Borntraeger --- arch/s390/kvm/kvm-s390.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 8cd8e7b..f5282e6 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -1720,6 +1720,8 @@ static bool ibs_enabled(struct kvm_vcpu *vcpu) static int kvm_s390_handle_requests(struct kvm_vcpu *vcpu) { + if (!vcpu->requests) + return 0; retry: s390_vcpu_unblock(vcpu); /* -- 2.7.4