| Message ID | 20240429155738.990025-2-alejandro.j.jimenez@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Export APICv-related state via binary stats interface | expand |
On 4/29/2024 9:27 PM, Alejandro Jimenez wrote: > Expose the APICv activation status of individual vCPUs via the stats > subsystem. In special cases a vCPU's APICv can be deactivated/disabled > even though there are no VM-wide inhibition reasons. The only current > example of this is AVIC for a vCPU running in nested mode. This type of > inhibition is not recorded in the VM inhibit reasons or visible in > current tracepoints. > > Signed-off-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com> Reviewed-by: Vasant Hegde <vasant.hegde@amd.com> -Vasant > --- > arch/x86/include/asm/kvm_host.h | 1 + > arch/x86/kvm/lapic.c | 1 + > arch/x86/kvm/x86.c | 2 ++ > 3 files changed, 4 insertions(+) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 1d13e3cd1dc5..12f30cb5c842 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -1573,6 +1573,7 @@ struct kvm_vcpu_stat { > u64 preemption_other; > u64 guest_mode; > u64 notify_window_exits; > + u64 apicv_active; > }; > > struct x86_instruction_info; > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index cf37586f0466..37fe75a5db8c 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -2872,6 +2872,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns) > */ > if (enable_apicv) { > apic->apicv_active = true; > + vcpu->stat.apicv_active = apic->apicv_active; > kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu); > } > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index e9ef1fa4b90b..0451c4c8d731 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -304,6 +304,7 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = { > STATS_DESC_COUNTER(VCPU, preemption_other), > STATS_DESC_IBOOLEAN(VCPU, guest_mode), > STATS_DESC_COUNTER(VCPU, notify_window_exits), > + STATS_DESC_IBOOLEAN(VCPU, apicv_active), > }; > > const struct kvm_stats_header kvm_vcpu_stats_header = { > @@ -10625,6 +10626,7 @@ void __kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu) > goto out; > > apic->apicv_active = activate; > + vcpu->stat.apicv_active = apic->apicv_active; > kvm_apic_update_apicv(vcpu); > static_call(kvm_x86_refresh_apicv_exec_ctrl)(vcpu); >
On Mon, Apr 29, 2024, Alejandro Jimenez wrote: > Expose the APICv activation status of individual vCPUs via the stats > subsystem. In special cases a vCPU's APICv can be deactivated/disabled > even though there are no VM-wide inhibition reasons. The only current > example of this is AVIC for a vCPU running in nested mode. This type of > inhibition is not recorded in the VM inhibit reasons or visible in > current tracepoints. > > Signed-off-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com> > --- > arch/x86/include/asm/kvm_host.h | 1 + > arch/x86/kvm/lapic.c | 1 + > arch/x86/kvm/x86.c | 2 ++ > 3 files changed, 4 insertions(+) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 1d13e3cd1dc5..12f30cb5c842 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -1573,6 +1573,7 @@ struct kvm_vcpu_stat { > u64 preemption_other; > u64 guest_mode; > u64 notify_window_exits; > + u64 apicv_active; Hrm, do we really have no way to effectively symlink stats to internal state? That seems like a flaw. It's obviously not the end of the world, but having to burn 8 bytes per vCPU for boolean stats that are 1:1 reflections of KVM state is going to be a deterrent for future stats. > }; > > struct x86_instruction_info; > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index cf37586f0466..37fe75a5db8c 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -2872,6 +2872,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns) > */ > if (enable_apicv) { > apic->apicv_active = true; > + vcpu->stat.apicv_active = apic->apicv_active; > kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu); > } > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index e9ef1fa4b90b..0451c4c8d731 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -304,6 +304,7 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = { > STATS_DESC_COUNTER(VCPU, preemption_other), > STATS_DESC_IBOOLEAN(VCPU, guest_mode), > STATS_DESC_COUNTER(VCPU, notify_window_exits), > + STATS_DESC_IBOOLEAN(VCPU, apicv_active), > }; > > const struct kvm_stats_header kvm_vcpu_stats_header = { > @@ -10625,6 +10626,7 @@ void __kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu) > goto out; > > apic->apicv_active = activate; > + vcpu->stat.apicv_active = apic->apicv_active; > kvm_apic_update_apicv(vcpu); > static_call(kvm_x86_refresh_apicv_exec_ctrl)(vcpu); > > -- > 2.39.3 >
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 1d13e3cd1dc5..12f30cb5c842 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1573,6 +1573,7 @@ struct kvm_vcpu_stat { u64 preemption_other; u64 guest_mode; u64 notify_window_exits; + u64 apicv_active; }; struct x86_instruction_info; diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index cf37586f0466..37fe75a5db8c 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -2872,6 +2872,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns) */ if (enable_apicv) { apic->apicv_active = true; + vcpu->stat.apicv_active = apic->apicv_active; kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu); } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e9ef1fa4b90b..0451c4c8d731 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -304,6 +304,7 @@ const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = { STATS_DESC_COUNTER(VCPU, preemption_other), STATS_DESC_IBOOLEAN(VCPU, guest_mode), STATS_DESC_COUNTER(VCPU, notify_window_exits), + STATS_DESC_IBOOLEAN(VCPU, apicv_active), }; const struct kvm_stats_header kvm_vcpu_stats_header = { @@ -10625,6 +10626,7 @@ void __kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu) goto out; apic->apicv_active = activate; + vcpu->stat.apicv_active = apic->apicv_active; kvm_apic_update_apicv(vcpu); static_call(kvm_x86_refresh_apicv_exec_ctrl)(vcpu);
Expose the APICv activation status of individual vCPUs via the stats subsystem. In special cases a vCPU's APICv can be deactivated/disabled even though there are no VM-wide inhibition reasons. The only current example of this is AVIC for a vCPU running in nested mode. This type of inhibition is not recorded in the VM inhibit reasons or visible in current tracepoints. Signed-off-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com> --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/lapic.c | 1 + arch/x86/kvm/x86.c | 2 ++ 3 files changed, 4 insertions(+)