[PATCH v6 12/12] KVM/VMX/vPMU: support to report GLOBAL_STATUS_LBRS_FROZEN

[Wei Wang]

Arch v4 supports streamlined Freeze_LBR_on_PMI. According to the SDM,
the LBR_FRZ bit is set to global status when debugctl.freeze_lbr_on_pmi
has been set and a PMI is generated. The CTR_FRZ bit is set when
debugctl.freeze_perfmon_on_pmi is set and a PMI is generated.

Signed-off-by: Wei Wang <wei.w.wang@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxx>
---
 arch/x86/kvm/pmu.c           | 11 +++++++++--
 arch/x86/kvm/pmu.h           |  1 +
 arch/x86/kvm/vmx/pmu_intel.c | 19 +++++++++++++++++++
 3 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 1e313f3..f5f1f46 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -55,6 +55,13 @@ static void kvm_pmi_trigger_fn(struct irq_work *irq_work)
 	kvm_pmu_deliver_pmi(vcpu);
 }
 
+static void kvm_perf_set_global_status(struct kvm_pmu *pmu, u8 idx)
+{
+	__set_bit(idx, (unsigned long *)&pmu->global_status);
+	if (kvm_x86_ops->pmu_ops->set_global_status)
+		kvm_x86_ops->pmu_ops->set_global_status(pmu, idx);
+}
+
 static void kvm_perf_overflow(struct perf_event *perf_event,
 			      struct perf_sample_data *data,
 			      struct pt_regs *regs)
@@ -64,7 +71,7 @@ static void kvm_perf_overflow(struct perf_event *perf_event,
 
 	if (!test_and_set_bit(pmc->idx,
 			      (unsigned long *)&pmu->reprogram_pmi)) {
-		__set_bit(pmc->idx, (unsigned long *)&pmu->global_status);
+		kvm_perf_set_global_status(pmu, pmc->idx);
 		kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
 	}
 }
@@ -78,7 +85,7 @@ static void kvm_perf_overflow_intr(struct perf_event *perf_event,
 
 	if (!test_and_set_bit(pmc->idx,
 			      (unsigned long *)&pmu->reprogram_pmi)) {
-		__set_bit(pmc->idx, (unsigned long *)&pmu->global_status);
+		kvm_perf_set_global_status(pmu, pmc->idx);
 		kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
 
 		/*
diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h
index cadf91a..408ddc2 100644
--- a/arch/x86/kvm/pmu.h
+++ b/arch/x86/kvm/pmu.h
@@ -24,6 +24,7 @@ struct kvm_pmu_ops {
 				    u8 unit_mask);
 	unsigned (*find_fixed_event)(int idx);
 	bool (*pmc_is_enabled)(struct kvm_pmc *pmc);
+	void (*set_global_status)(struct kvm_pmu *pmu, u8 idx);
 	struct kvm_pmc *(*pmc_idx_to_pmc)(struct kvm_pmu *pmu, int pmc_idx);
 	struct kvm_pmc *(*msr_idx_to_pmc)(struct kvm_vcpu *vcpu, unsigned idx,
 					  u64 *mask);
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index c60f564..62e7bcd 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -421,6 +421,24 @@ static bool intel_pmu_access_lbr_msr(struct kvm_vcpu *vcpu,
 	return ret;
 }
 
+static void intel_pmu_set_global_status(struct kvm_pmu *pmu, u8 idx)
+{
+	u64 guest_debugctl;
+
+	if (pmu->version >= 4) {
+		guest_debugctl = vmcs_read64(GUEST_IA32_DEBUGCTL);
+
+		if ((guest_debugctl & GLOBAL_STATUS_LBRS_FROZEN) ==
+		    DEBUGCTLMSR_FREEZE_LBRS_ON_PMI)
+			__set_bit(GLOBAL_STATUS_LBRS_FROZEN,
+				  (unsigned long *)&pmu->global_status);
+		if ((guest_debugctl & GLOBAL_STATUS_LBRS_FROZEN) ==
+		    DEBUGCTLMSR_FREEZE_PERFMON_ON_PMI)
+			__set_bit(GLOBAL_STATUS_COUNTERS_FROZEN,
+				  (unsigned long *)&pmu->global_status);
+	}
+}
+
 static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 {
 	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
@@ -719,6 +737,7 @@ void intel_pmu_disable_save_guest_lbr(struct kvm_vcpu *vcpu)
 struct kvm_pmu_ops intel_pmu_ops = {
 	.find_arch_event = intel_find_arch_event,
 	.find_fixed_event = intel_find_fixed_event,
+	.set_global_status = intel_pmu_set_global_status,
 	.pmc_is_enabled = intel_pmc_is_enabled,
 	.pmc_idx_to_pmc = intel_pmc_idx_to_pmc,
 	.msr_idx_to_pmc = intel_msr_idx_to_pmc,
-- 
2.7.4