KVM: SVM: Add AVIC doorbell tracepoint

Add a tracepoint to track number of doorbells being sent
to signal a running vCPU to process IRQ after being injected.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Message-Id: <20220519102709.24125-17-suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 229de5f..f18c852 100644 (file)
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -324,8 +324,10 @@ void avic_ring_doorbell(struct kvm_vcpu *vcpu)
         */
        int cpu = READ_ONCE(vcpu->cpu);
 
-       if (cpu != get_cpu())
+       if (cpu != get_cpu()) {
                wrmsrl(MSR_AMD64_SVM_AVIC_DOORBELL, kvm_cpu_get_apicid(cpu));
+               trace_kvm_avic_doorbell(vcpu->vcpu_id, kvm_cpu_get_apicid(cpu));
+       }
        put_cpu();
 }
 

diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index fd28dd4..bc85622 100644 (file)
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -1490,6 +1490,24 @@ TRACE_EVENT(kvm_avic_kick_vcpu_slowpath,
                  __entry->icrh, __entry->icrl, __entry->index)
 );
 
+TRACE_EVENT(kvm_avic_doorbell,
+           TP_PROTO(u32 vcpuid, u32 apicid),
+           TP_ARGS(vcpuid, apicid),
+
+       TP_STRUCT__entry(
+               __field(u32, vcpuid)
+               __field(u32, apicid)
+       ),
+
+       TP_fast_assign(
+               __entry->vcpuid = vcpuid;
+               __entry->apicid = apicid;
+       ),
+
+       TP_printk("vcpuid=%u, apicid=%u",
+                 __entry->vcpuid, __entry->apicid)
+);
+
 TRACE_EVENT(kvm_hv_timer_state,
                TP_PROTO(unsigned int vcpu_id, unsigned int hv_timer_in_use),
                TP_ARGS(vcpu_id, hv_timer_in_use),

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index acd7ce1..d88600e 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -13328,6 +13328,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_unaccelerated_access);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_incomplete_ipi);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_ga_log);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_kick_vcpu_slowpath);
+EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_avic_doorbell);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_apicv_accept_irq);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_enter);
 EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_vmgexit_exit);