KVM: x86/pmu: Provide Intel PMU's pmc_is_enabled() as generic x86 code

Move the Intel PMU implementation of pmc_is_enabled() to common x86 code
as pmc_is_globally_enabled(), and drop AMD's implementation.  AMD PMU
currently supports only v1, and thus not PERF_GLOBAL_CONTROL, thus the
semantics for AMD are unchanged.  And when support for AMD PMU v2 comes
along, the common behavior will also Just Work.

Signed-off-by: Like Xu <likexu@tencent.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20230603011058.1038821-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 15 insertions, 1 deletions

diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h
index 7c2c64142443..f77bfc7ede42 100644
--- a/arch/x86/kvm/pmu.h
+++ b/arch/x86/kvm/pmu.h
@@ -20,7 +20,6 @@
 
 struct kvm_pmu_ops {
 	bool (*hw_event_available)(struct kvm_pmc *pmc);
-	bool (*pmc_is_enabled)(struct kvm_pmc *pmc);
 	struct kvm_pmc *(*pmc_idx_to_pmc)(struct kvm_pmu *pmu, int pmc_idx);
 	struct kvm_pmc *(*rdpmc_ecx_to_pmc)(struct kvm_vcpu *vcpu,
 		unsigned int idx, u64 *mask);
@@ -227,6 +226,21 @@ static inline void reprogram_counters(struct kvm_pmu *pmu, u64 diff)
 	kvm_make_request(KVM_REQ_PMU, pmu_to_vcpu(pmu));
 }
 
+/*
+ * Check if a PMC is enabled by comparing it against global_ctrl bits.
+ *
+ * If the vPMU doesn't have global_ctrl MSR, all vPMCs are enabled.
+ */
+static inline bool pmc_is_globally_enabled(struct kvm_pmc *pmc)
+{
+	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
+
+	if (!kvm_pmu_has_perf_global_ctrl(pmu))
+		return true;
+
+	return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl);
+}
+
 void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu);
 void kvm_pmu_handle_event(struct kvm_vcpu *vcpu);
 int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned pmc, u64 *data);