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.w...@intel.com>
Cc: Andi Kleen <a...@linux.intel.com>
Cc: Paolo Bonzini <pbonz...@redhat.com>
Cc: Kan Liang <kan.li...@intel.com>
---
 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

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