> -----Original Message----- > From: Radim Krčmář <[email protected]> > Sent: Wednesday, March 28, 2018 3:31 PM > To: Moger, Babu <[email protected]> > Cc: [email protected]; [email protected]; [email protected]; > [email protected]; [email protected]; [email protected]; > [email protected]; [email protected] > Subject: Re: [PATCH v2 5/5] KVM: SVM: Implement pause loop exit logic in > SVM > > 2018-03-16 16:37-0400, Babu Moger: > > Bring the PLE(pause loop exit) logic to AMD svm driver. > > > > While testing, we found this helping in situations where numerous > > pauses are generated. Without these patches we could see continuos > > VMEXITS due to pause interceptions. Tested it on AMD EPYC server with > > boot parameter idle=poll on a VM with 32 vcpus to simulate extensive > > pause behaviour. Here are VMEXITS in 10 seconds interval. > > > > #VMEXITS Before the change After the change > > Pauses 810199 504 > > Total 882184 325415 > > > > Signed-off-by: Babu Moger <[email protected]> > > --- > > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > > @@ -1046,6 +1094,42 @@ static int avic_ga_log_notifier(u32 ga_tag) > > return 0; > > } > > > > +static void grow_ple_window(struct kvm_vcpu *vcpu) > > +{ > > + struct vcpu_svm *svm = to_svm(vcpu); > > + struct vmcb_control_area *control = &svm->vmcb->control; > > + int old = control->pause_filter_count; > > + > > + control->pause_filter_count = __grow_ple_window(old, > > + pause_filter_count, > > + > pause_filter_count_grow, > > + > pause_filter_count_max); > > + > > + if (control->pause_filter_count != old) > > + mark_dirty(svm->vmcb, VMCB_INTERCEPTS); > > + > > + trace_kvm_ple_window_grow(vcpu->vcpu_id, > > + control->pause_filter_count, old); > > +} > > + > > +static void shrink_ple_window(struct kvm_vcpu *vcpu) > > +{ > > + struct vcpu_svm *svm = to_svm(vcpu); > > + struct vmcb_control_area *control = &svm->vmcb->control; > > + int old = control->pause_filter_count; > > + > > + control->pause_filter_count = > > + __shrink_ple_window(old, > > + pause_filter_count, > > + pause_filter_count_shrink, > > + 0); > > I've used pause_filter_count as minumum here as well and in all patches > used 'unsigned int' instead of 'uint' in the code too match the rest of > the kernel. > > The series is in kvm/queue, please look at the changes and tell me if > you'd like something done differently, thanks.
Ok. Looks good to me. Thanks.
