HVM-701 need static instrumentation in kvm_ctx_save()/kvm_ctx_restore()

3 files changed, 50 insertions, 1 deletions

diff --git a/kvm.c b/kvm.c
index 3625750..a7a9998 100644
--- a/kvm.c
+++ b/kvm.c
@@ -421,6 +421,19 @@ kvm_fire_urn(struct kvm_vcpu *vcpu)
 		vcpu->urn->on_user_return(vcpu, vcpu->urn);
 }
 
+void
+kvm_ringbuf_record(kvm_ringbuf_t *ringbuf, uint32_t tag, uint64_t payload)
+{
+	kvm_ringbuf_entry_t *ent = &ringbuf->kvmr_buf[ringbuf->kvmr_ent++ &
+	    (KVM_RINGBUF_NENTRIES - 1)];
+
+	ent->kvmre_tag = tag;
+	ent->kvmre_cpuid = curthread->t_cpu->cpu_id;
+	ent->kvmre_thread = (uintptr_t)curthread;
+	ent->kvmre_tsc = gethrtime_unscaled();
+	ent->kvmre_payload = payload;
+}
+
 /*
  * Called when we've been asked to save our context. i.e. we're being swapped
  * out.
@@ -429,6 +442,8 @@ void
 kvm_ctx_save(void *arg)
 {
 	struct kvm_vcpu *vcpu = arg;
+	kvm_ringbuf_record(&vcpu->kvcpu_ringbuf,
+	    KVM_RINGBUF_TAG_CTXSAVE, vcpu->cpu);
 	kvm_arch_vcpu_put(vcpu);
 	kvm_fire_urn(vcpu);
 }
@@ -444,6 +459,8 @@ kvm_ctx_restore(void *arg)
 
 	cpu = CPU->cpu_seqid;
 	struct kvm_vcpu *vcpu = arg;
+	kvm_ringbuf_record(&vcpu->kvcpu_ringbuf,
+	    KVM_RINGBUF_TAG_CTXRESTORE, vcpu->cpu);
 	kvm_arch_vcpu_load(vcpu, cpu);
 }
 
diff --git a/kvm_host.h b/kvm_host.h
index 81ea4e0..b520ea7 100644
--- a/kvm_host.h
+++ b/kvm_host.h
@@ -100,6 +100,29 @@ extern int kvm_io_bus_unregister_dev(struct kvm *, enum kvm_bus,
 
 #define	KVM_MAX_IRQ_ROUTES 1024
 
+#define	KVM_RINGBUF_NENTRIES	512
+
+#define	KVM_RINGBUF_TAG_CTXSAVE		1
+#define	KVM_RINGBUF_TAG_CTXRESTORE	2
+#define	KVM_RINGBUF_TAG_VMPTRLD		3
+#define	KVM_RINGBUF_TAG_VCPUMIGRATE	4
+#define	KVM_RINGBUF_TAG_VCPUCLEAR	5
+
+typedef struct kvm_ringbuf_entry {
+	uint32_t kvmre_tag;			/* tag for this entry */
+	uint32_t kvmre_cpuid;			/* CPU of entry */
+	uint64_t kvmre_thread;			/* thread for entry */
+	uint64_t kvmre_tsc;			/* TSC at time of entry */
+	uint64_t kvmre_payload;			/* payload for this entry */
+} kvm_ringbuf_entry_t;
+
+typedef struct kvm_ringbuf {
+	kvm_ringbuf_entry_t kvmr_buf[KVM_RINGBUF_NENTRIES]; /* ring buffer */
+	uint32_t kvmr_ent;			/* current entry */
+} kvm_ringbuf_t;
+
+extern void kvm_ringbuf_record(kvm_ringbuf_t *, uint32_t, uint64_t);
+
 typedef struct kvm_vcpu {
 	struct kvm *kvm;
 	int vcpu_id;
@@ -117,7 +140,7 @@ typedef struct kvm_vcpu {
 	kcondvar_t kvcpu_kick_cv;
 	kvm_vcpu_stats_t kvcpu_stats;
 	kstat_t *kvcpu_kstat;
-
+	kvm_ringbuf_t kvcpu_ringbuf;
 	int sigset_active;
 	sigset_t sigset;
 	int mmio_needed;
diff --git a/kvm_vmx.c b/kvm_vmx.c
index 6894ef6..c04d0eb 100644
--- a/kvm_vmx.c
+++ b/kvm_vmx.c
@@ -497,6 +497,9 @@ __vcpu_clear(void *arg)
 
 	vmx->vmcs->revision_id = vmcs_config.revision_id;
 
+	kvm_ringbuf_record(&vmx->vcpu.kvcpu_ringbuf,
+	    KVM_RINGBUF_TAG_VCPUCLEAR, vmx->vcpu.cpu);
+
 	if (vmx->vcpu.cpu == cpu)
 		vmcs_clear(vmx->vmcs_pa);
 
@@ -840,6 +843,9 @@ vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 	if (current_vmcs[cpu] != vmx->vmcs) {
 		uint8_t error;
 
+		kvm_ringbuf_record(&vcpu->kvcpu_ringbuf,
+		    KVM_RINGBUF_TAG_VMPTRLD, (uint64_t)current_vmcs[cpu]);
+
 		current_vmcs[cpu] = vmx->vmcs;
 
 		KVM_TRACE1(vmx__vmptrld, uint64_t, phys_addr);
@@ -854,6 +860,9 @@ vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 		struct descriptor_table dt;
 		unsigned long sysenter_esp;
 
+		kvm_ringbuf_record(&vcpu->kvcpu_ringbuf,
+		    KVM_RINGBUF_TAG_VCPUMIGRATE, vcpu->cpu);
+
 		vcpu->cpu = cpu;
 
 		/*