From: Wanpeng Li <wanpengli@xxxxxxxxxxx>
Commit 8566ac8b (KVM: SVM: Implement pause loop exit logic in SVM) drops
disable pause loop exit/pause filtering capability completely, I guess it
is a merge fault by Radim since disable vmexits capabilities and pause
loop exit for SVM patchsets are merged at the same time. This patch
reintroduces the disable pause loop exit/pause filtering capability
support.
We can observe 2.9% hackbench improvement for a 92 vCPUs guest on AMD
Rome Server.
Reported-by: Haiwei Li <lihaiwei@xxxxxxxxxxx>
Tested-by: Haiwei Li <lihaiwei@xxxxxxxxxxx>
Fixes: 8566ac8b (KVM: SVM: Implement pause loop exit logic in SVM)
Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
---
arch/x86/kvm/svm/svm.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index c0da4dd..c20f127 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1090,7 +1090,7 @@ static void init_vmcb(struct vcpu_svm *svm)
svm->nested.vmcb = 0;
svm->vcpu.arch.hflags = 0;
- if (pause_filter_count) {
+ if (pause_filter_count && !kvm_pause_in_guest(svm->vcpu.kvm)) {
control->pause_filter_count = pause_filter_count;
if (pause_filter_thresh)
control->pause_filter_thresh = pause_filter_thresh;
@@ -2693,7 +2693,7 @@ static int pause_interception(struct vcpu_svm *svm)
struct kvm_vcpu *vcpu = &svm->vcpu;
bool in_kernel = (svm_get_cpl(vcpu) == 0);
- if (pause_filter_thresh)
+ if (!kvm_pause_in_guest(vcpu->kvm))
grow_ple_window(vcpu);
kvm_vcpu_on_spin(vcpu, in_kernel);
@@ -3780,7 +3780,7 @@ static void svm_handle_exit_irqoff(struct kvm_vcpu *vcpu)
static void svm_sched_in(struct kvm_vcpu *vcpu, int cpu)
{
- if (pause_filter_thresh)
+ if (!kvm_pause_in_guest(vcpu->kvm))
shrink_ple_window(vcpu);
}
@@ -3958,6 +3958,9 @@ static void svm_vm_destroy(struct kvm *kvm)
static int svm_vm_init(struct kvm *kvm)
{
+ if (!pause_filter_thresh)
+ kvm->arch.pause_in_guest = true;
+
if (avic) {
int ret = avic_vm_init(kvm);
if (ret)
--
2.7.4
