From: Marc Zyngier <[email protected]> As we are about to allow selection of the PMU exposed to a guest, start by keeping track of the default one instead of only the PMU version.
Signed-off-by: Marc Zyngier <[email protected]> Signed-off-by: Alexandru Elisei <[email protected]> --- arch/arm64/include/asm/kvm_host.h | 2 +- arch/arm64/kvm/pmu-emul.c | 42 +++++++++++++++++++------------ 2 files changed, 27 insertions(+), 17 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 2869259e10c0..57141a3a3740 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -129,7 +129,7 @@ struct kvm_arch { * up to 2^10 events (ARMv8.0) or 2^16 events (ARMv8.1+). */ unsigned long *pmu_filter; - unsigned int pmuver; + struct arm_pmu *arm_pmu; u8 pfr0_csv2; u8 pfr0_csv3; diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index bc771bc1a041..b238b3d5515c 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -24,7 +24,11 @@ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc); static u32 kvm_pmu_event_mask(struct kvm *kvm) { - switch (kvm->arch.pmuver) { + unsigned int pmuver; + + pmuver = kvm->arch.arm_pmu->pmuver; + + switch (pmuver) { case ID_AA64DFR0_PMUVER_8_0: return GENMASK(9, 0); case ID_AA64DFR0_PMUVER_8_1: @@ -33,7 +37,7 @@ static u32 kvm_pmu_event_mask(struct kvm *kvm) case ID_AA64DFR0_PMUVER_8_7: return GENMASK(15, 0); default: /* Shouldn't be here, just for sanity */ - WARN_ONCE(1, "Unknown PMU version %d\n", kvm->arch.pmuver); + WARN_ONCE(1, "Unknown PMU version %d\n", pmuver); return 0; } } @@ -600,6 +604,7 @@ static bool kvm_pmu_counter_is_enabled(struct kvm_vcpu *vcpu, u64 select_idx) */ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx) { + struct arm_pmu *arm_pmu = vcpu->kvm->arch.arm_pmu; struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_pmc *pmc; struct perf_event *event; @@ -636,7 +641,7 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx) return; memset(&attr, 0, sizeof(struct perf_event_attr)); - attr.type = PERF_TYPE_RAW; + attr.type = arm_pmu->pmu.type; attr.size = sizeof(attr); attr.pinned = 1; attr.disabled = !kvm_pmu_counter_is_enabled(vcpu, pmc->idx); @@ -750,12 +755,11 @@ void kvm_host_pmu_init(struct arm_pmu *pmu) static_branch_enable(&kvm_arm_pmu_available); } -static int kvm_pmu_probe_pmuver(void) +static struct arm_pmu *kvm_pmu_probe_armpmu(void) { struct perf_event_attr attr = { }; struct perf_event *event; - struct arm_pmu *pmu; - int pmuver = ID_AA64DFR0_PMUVER_IMP_DEF; + struct arm_pmu *pmu = NULL; /* * Create a dummy event that only counts user cycles. As we'll never @@ -780,19 +784,20 @@ static int kvm_pmu_probe_pmuver(void) if (IS_ERR(event)) { pr_err_once("kvm: pmu event creation failed %ld\n", PTR_ERR(event)); - return ID_AA64DFR0_PMUVER_IMP_DEF; + return NULL; } if (event->pmu) { pmu = to_arm_pmu(event->pmu); - if (pmu->pmuver) - pmuver = pmu->pmuver; + if (pmu->pmuver == 0 || + pmu->pmuver == ID_AA64DFR0_PMUVER_IMP_DEF) + pmu = NULL; } perf_event_disable(event); perf_event_release_kernel(event); - return pmuver; + return pmu; } u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) @@ -810,7 +815,7 @@ u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) * Don't advertise STALL_SLOT, as PMMIR_EL0 is handled * as RAZ */ - if (vcpu->kvm->arch.pmuver >= ID_AA64DFR0_PMUVER_8_4) + if (vcpu->kvm->arch.arm_pmu->pmuver >= ID_AA64DFR0_PMUVER_8_4) val &= ~BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32); base = 32; } @@ -932,11 +937,16 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) if (vcpu->arch.pmu.created) return -EBUSY; - if (!vcpu->kvm->arch.pmuver) - vcpu->kvm->arch.pmuver = kvm_pmu_probe_pmuver(); - - if (vcpu->kvm->arch.pmuver == ID_AA64DFR0_PMUVER_IMP_DEF) - return -ENODEV; + mutex_lock(&kvm->lock); + if (!kvm->arch.arm_pmu) { + /* No PMU set, get the default one */ + kvm->arch.arm_pmu = kvm_pmu_probe_armpmu(); + if (!kvm->arch.arm_pmu) { + mutex_unlock(&kvm->lock); + return -ENODEV; + } + } + mutex_unlock(&kvm->lock); switch (attr->attr) { case KVM_ARM_VCPU_PMU_V3_IRQ: { -- 2.34.1 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
