diff mbox series

[RFC,v3,19/58] KVM: x86/pmu: Plumb through pass-through PMU to vcpu for Intel CPUs

Message ID 20240801045907.4010984-20-mizhang@google.com (mailing list archive)
State New, archived
Headers show
Series Mediated Passthrough vPMU 3.0 for x86 | expand

Commit Message

Mingwei Zhang Aug. 1, 2024, 4:58 a.m. UTC 
Plumb through pass-through PMU setting from kvm->arch into kvm_pmu on each
vcpu created. Note that enabling PMU is decided by VMM when it sets the
CPUID bits exposed to guest VM. So plumb through the enabling for each pmu
in intel_pmu_refresh().

Co-developed-by: Xiong Zhang <xiong.y.zhang@linux.intel.com>
Signed-off-by: Xiong Zhang <xiong.y.zhang@linux.intel.com>
Signed-off-by: Mingwei Zhang <mizhang@google.com>
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Tested-by: Yongwei Ma <yongwei.ma@intel.com>
---
 arch/x86/include/asm/kvm_host.h |  2 ++
 arch/x86/kvm/pmu.c              |  1 +
 arch/x86/kvm/vmx/pmu_intel.c    | 12 +++++++++---
 3 files changed, 12 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index a15c783f20b9..4b3ce6194bdb 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -595,6 +595,8 @@  struct kvm_pmu {
 	 * redundant check before cleanup if guest don't use vPMU at all.
 	 */
 	u8 event_count;
+
+	bool passthrough;
 };
 
 struct kvm_pmu_ops;
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index a593b03c9aed..5768ea2935e9 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -797,6 +797,7 @@  void kvm_pmu_init(struct kvm_vcpu *vcpu)
 
 	memset(pmu, 0, sizeof(*pmu));
 	static_call(kvm_x86_pmu_init)(vcpu);
+	pmu->passthrough = false;
 	kvm_pmu_refresh(vcpu);
 }
 
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index be40474de6e4..e417fd91e5fe 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -470,15 +470,21 @@  static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
 		return;
 
 	entry = kvm_find_cpuid_entry(vcpu, 0xa);
-	if (!entry)
+	if (!entry || !vcpu->kvm->arch.enable_pmu) {
+		pmu->passthrough = false;
 		return;
-
+	}
 	eax.full = entry->eax;
 	edx.full = entry->edx;
 
 	pmu->version = eax.split.version_id;
-	if (!pmu->version)
+	if (!pmu->version) {
+		pmu->passthrough = false;
 		return;
+	}
+
+	pmu->passthrough = vcpu->kvm->arch.enable_passthrough_pmu &&
+			   lapic_in_kernel(vcpu);
 
 	pmu->nr_arch_gp_counters = min_t(int, eax.split.num_counters,
 					 kvm_pmu_cap.num_counters_gp);