// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2015 Linaro Ltd. * Author: Shannon Zhao */ #include #include #include #include #include #include #include #include static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx); /** * kvm_pmu_get_counter_value - get PMU counter value * @vcpu: The vcpu pointer * @select_idx: The counter index */ u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx) { u64 counter, reg, enabled, running; struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_pmc *pmc = &pmu->pmc[select_idx]; reg = (select_idx == ARMV8_PMU_CYCLE_IDX) ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + select_idx; counter = __vcpu_sys_reg(vcpu, reg); /* The real counter value is equal to the value of counter register plus * the value perf event counts. */ if (pmc->perf_event) counter += perf_event_read_value(pmc->perf_event, &enabled, &running); return counter & pmc->bitmask; } /** * kvm_pmu_set_counter_value - set PMU counter value * @vcpu: The vcpu pointer * @select_idx: The counter index * @val: The counter value */ void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val) { u64 reg; reg = (select_idx == ARMV8_PMU_CYCLE_IDX) ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + select_idx; __vcpu_sys_reg(vcpu, reg) += (s64)val - kvm_pmu_get_counter_value(vcpu, select_idx); /* Recreate the perf event to reflect the updated sample_period */ kvm_pmu_create_perf_event(vcpu, select_idx); } /** * kvm_pmu_release_perf_event - remove the perf event * @pmc: The PMU counter pointer */ static void kvm_pmu_release_perf_event(struct kvm_pmc *pmc) { if (pmc->perf_event) { perf_event_disable(pmc->perf_event); perf_event_release_kernel(pmc->perf_event); pmc->perf_event = NULL; } } /** * kvm_pmu_stop_counter - stop PMU counter * @pmc: The PMU counter pointer * * If this counter has been configured to monitor some event, release it here. */ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc) { u64 counter, reg; if (pmc->perf_event) { counter = kvm_pmu_get_counter_value(vcpu, pmc->idx); reg = (pmc->idx == ARMV8_PMU_CYCLE_IDX) ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + pmc->idx; __vcpu_sys_reg(vcpu, reg) = counter; kvm_pmu_release_perf_event(pmc); } } /** * kvm_pmu_vcpu_reset - reset pmu state for cpu * @vcpu: The vcpu pointer * */ void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu) { int i; struct kvm_pmu *pmu = &vcpu->arch.pmu; for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++) { kvm_pmu_stop_counter(vcpu, &pmu->pmc[i]); pmu->pmc[i].idx = i; pmu->pmc[i].bitmask = 0xffffffffUL; } } /** * kvm_pmu_vcpu_destroy - free perf event of PMU for cpu * @vcpu: The vcpu pointer * */ void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu) { int i; struct kvm_pmu *pmu = &vcpu->arch.pmu; for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++) kvm_pmu_release_perf_event(&pmu->pmc[i]); } u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu) { u64 val = __vcpu_sys_reg(vcpu, PMCR_EL0) >> ARMV8_PMU_PMCR_N_SHIFT; val &= ARMV8_PMU_PMCR_N_MASK; if (val == 0) return BIT(ARMV8_PMU_CYCLE_IDX); else return GENMASK(val - 1, 0) | BIT(ARMV8_PMU_CYCLE_IDX); } /** * kvm_pmu_enable_counter_mask - enable selected PMU counters * @vcpu: The vcpu pointer * @val: the value guest writes to PMCNTENSET register * * Call perf_event_enable to start counting the perf event */ void kvm_pmu_enable_counter_mask(struct kvm_vcpu *vcpu, u64 val) { int i; struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_pmc *pmc; if (!(__vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E) || !val) return; for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++) { if (!(val & BIT(i))) continue; pmc = &pmu->pmc[i]; if (pmc->perf_event) { perf_event_enable(pmc->perf_event); if (pmc->perf_event->state != PERF_EVENT_STATE_ACTIVE) kvm_debug("fail to enable perf event\n"); } } } /** * kvm_pmu_disable_counter_mask - disable selected PMU counters * @vcpu: The vcpu pointer * @val: the value guest writes to PMCNTENCLR register * * Call perf_event_disable to stop counting the perf event */ void kvm_pmu_disable_counter_mask(struct kvm_vcpu *vcpu, u64 val) { int i; struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_pmc *pmc; if (!val) return; for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++) { if (!(val & BIT(i))) continue; pmc = &pmu->pmc[i]; if (pmc->perf_event) perf_event_disable(pmc->perf_event); } } static u64 kvm_pmu_overflow_status(struct kvm_vcpu *vcpu) { u64 reg = 0; if ((__vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E)) { reg = __vcpu_sys_reg(vcpu, PMOVSSET_EL0); reg &= __vcpu_sys_reg(vcpu, PMCNTENSET_EL0); reg &= __vcpu_sys_reg(vcpu, PMINTENSET_EL1); reg &= kvm_pmu_valid_counter_mask(vcpu); } return reg; } static void kvm_pmu_update_state(struct kvm_vcpu *vcpu) { struct kvm_pmu *pmu = &vcpu->arch.pmu; bool overflow; if (!kvm_arm_pmu_v3_ready(vcpu)) return; overflow = !!kvm_pmu_overflow_status(vcpu); if (pmu->irq_level == overflow) return; pmu->irq_level = overflow; if (likely(irqchip_in_kernel(vcpu->kvm))) { int ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id, pmu->irq_num, overflow, pmu); WARN_ON(ret); } } bool kvm_pmu_should_notify_user(struct kvm_vcpu *vcpu) { struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_sync_regs *sregs = &vcpu->run->s.regs; bool run_level = sregs->device_irq_level & KVM_ARM_DEV_PMU; if (likely(irqchip_in_kernel(vcpu->kvm))) return false; return pmu->irq_level != run_level; } /* * Reflect the PMU overflow interrupt output level into the kvm_run structure */ void kvm_pmu_update_run(struct kvm_vcpu *vcpu) { struct kvm_sync_regs *regs = &vcpu->run->s.regs; /* Populate the timer bitmap for user space */ regs->device_irq_level &= ~KVM_ARM_DEV_PMU; if (vcpu->arch.pmu.irq_level) regs->device_irq_level |= KVM_ARM_DEV_PMU; } /** * kvm_pmu_flush_hwstate - flush pmu state to cpu * @vcpu: The vcpu pointer * * Check if the PMU has overflowed while we were running in the host, and inject * an interrupt if that was the case. */ void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) { kvm_pmu_update_state(vcpu); } /** * kvm_pmu_sync_hwstate - sync pmu state from cpu * @vcpu: The vcpu pointer * * Check if the PMU has overflowed while we were running in the guest, and * inject an interrupt if that was the case. */ void kvm_pmu_sync_hwstate(struct kvm_vcpu *vcpu) { kvm_pmu_update_state(vcpu); } static inline struct kvm_vcpu *kvm_pmc_to_vcpu(struct kvm_pmc *pmc) { struct kvm_pmu *pmu; struct kvm_vcpu_arch *vcpu_arch; pmc -= pmc->idx; pmu = container_of(pmc, struct kvm_pmu, pmc[0]); vcpu_arch = container_of(pmu, struct kvm_vcpu_arch, pmu); return container_of(vcpu_arch, struct kvm_vcpu, arch); } /** * When the perf event overflows, set the overflow status and inform the vcpu. */ static void kvm_pmu_perf_overflow(struct perf_event *perf_event, struct perf_sample_data *data, struct pt_regs *regs) { struct kvm_pmc *pmc = perf_event->overflow_handler_context; struct kvm_vcpu *vcpu = kvm_pmc_to_vcpu(pmc); int idx = pmc->idx; __vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= BIT(idx); if (kvm_pmu_overflow_status(vcpu)) { kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu); kvm_vcpu_kick(vcpu); } } /** * kvm_pmu_software_increment - do software increment * @vcpu: The vcpu pointer * @val: the value guest writes to PMSWINC register */ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val) { int i; u64 type, enable, reg; if (val == 0) return; enable = __vcpu_sys_reg(vcpu, PMCNTENSET_EL0); for (i = 0; i < ARMV8_PMU_CYCLE_IDX; i++) { if (!(val & BIT(i))) continue; type = __vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + i) & ARMV8_PMU_EVTYPE_EVENT; if ((type == ARMV8_PMUV3_PERFCTR_SW_INCR) && (enable & BIT(i))) { reg = __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) + 1; reg = lower_32_bits(reg); __vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) = reg; if (!reg) __vcpu_sys_reg(vcpu, PMOVSSET_EL0) |= BIT(i); } } } /** * kvm_pmu_handle_pmcr - handle PMCR register * @vcpu: The vcpu pointer * @val: the value guest writes to PMCR register */ void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val) { struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_pmc *pmc; u64 mask; int i; mask = kvm_pmu_valid_counter_mask(vcpu); if (val & ARMV8_PMU_PMCR_E) { kvm_pmu_enable_counter_mask(vcpu, __vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & mask); } else { kvm_pmu_disable_counter_mask(vcpu, mask); } if (val & ARMV8_PMU_PMCR_C) kvm_pmu_set_counter_value(vcpu, ARMV8_PMU_CYCLE_IDX, 0); if (val & ARMV8_PMU_PMCR_P) { for (i = 0; i < ARMV8_PMU_CYCLE_IDX; i++) kvm_pmu_set_counter_value(vcpu, i, 0); } if (val & ARMV8_PMU_PMCR_LC) { pmc = &pmu->pmc[ARMV8_PMU_CYCLE_IDX]; pmc->bitmask = 0xffffffffffffffffUL; } } static bool kvm_pmu_counter_is_enabled(struct kvm_vcpu *vcpu, u64 select_idx) { return (__vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E) && (__vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & BIT(select_idx)); } /** * kvm_pmu_create_perf_event - create a perf event for a counter * @vcpu: The vcpu pointer * @select_idx: The number of selected counter */ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx) { struct kvm_pmu *pmu = &vcpu->arch.pmu; struct kvm_pmc *pmc = &pmu->pmc[select_idx]; struct perf_event *event; struct perf_event_attr attr; u64 eventsel, counter, reg, data; reg = (select_idx == ARMV8_PMU_CYCLE_IDX) ? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + select_idx; data = __vcpu_sys_reg(vcpu, reg); kvm_pmu_stop_counter(vcpu, pmc); eventsel = data & ARMV8_PMU_EVTYPE_EVENT; /* Software increment event does't need to be backed by a perf event */ if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR && select_idx != ARMV8_PMU_CYCLE_IDX) return; memset(&attr, 0, sizeof(struct perf_event_attr)); attr.type = PERF_TYPE_RAW; attr.size = sizeof(attr); attr.pinned = 1; attr.disabled = !kvm_pmu_counter_is_enabled(vcpu, select_idx); attr.exclude_user = data & ARMV8_PMU_EXCLUDE_EL0 ? 1 : 0; attr.exclude_kernel = data & ARMV8_PMU_EXCLUDE_EL1 ? 1 : 0; attr.exclude_hv = 1; /* Don't count EL2 events */ attr.exclude_host = 1; /* Don't count host events */ attr.config = (select_idx == ARMV8_PMU_CYCLE_IDX) ? ARMV8_PMUV3_PERFCTR_CPU_CYCLES : eventsel; counter = kvm_pmu_get_counter_value(vcpu, select_idx); /* The initial sample period (overflow count) of an event. */ attr.sample_period = (-counter) & pmc->bitmask; event = perf_event_create_kernel_counter(&attr, -1, current, kvm_pmu_perf_overflow, pmc); if (IS_ERR(event)) { pr_err_once("kvm: pmu event creation failed %ld\n", PTR_ERR(event)); return; } pmc->perf_event = event; } /** * kvm_pmu_set_counter_event_type - set selected counter to monitor some event * @vcpu: The vcpu pointer * @data: The data guest writes to PMXEVTYPER_EL0 * @select_idx: The number of selected counter * * When OS accesses PMXEVTYPER_EL0, that means it wants to set a PMC to count an * event with given hardware event number. Here we call perf_event API to * emulate this action and create a kernel perf event for it. */ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, u64 select_idx) { u64 reg, event_type = data & ARMV8_PMU_EVTYPE_MASK; reg = (select_idx == ARMV8_PMU_CYCLE_IDX) ? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + select_idx; __vcpu_sys_reg(vcpu, reg) = event_type; kvm_pmu_create_perf_event(vcpu, select_idx); } bool kvm_arm_support_pmu_v3(void) { /* * Check if HW_PERF_EVENTS are supported by checking the number of * hardware performance counters. This could ensure the presence of * a physical PMU and CONFIG_PERF_EVENT is selected. */ return (perf_num_counters() > 0); } int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu) { if (!vcpu->arch.pmu.created) return 0; /* * A valid interrupt configuration for the PMU is either to have a * properly configured interrupt number and using an in-kernel * irqchip, or to not have an in-kernel GIC and not set an IRQ. */ if (irqchip_in_kernel(vcpu->kvm)) { int irq = vcpu->arch.pmu.irq_num; if (!kvm_arm_pmu_irq_initialized(vcpu)) return -EINVAL; /* * If we are using an in-kernel vgic, at this point we know * the vgic will be initialized, so we can check the PMU irq * number against the dimensions of the vgic and make sure * it's valid. */ if (!irq_is_ppi(irq) && !vgic_valid_spi(vcpu->kvm, irq)) return -EINVAL; } else if (kvm_arm_pmu_irq_initialized(vcpu)) { return -EINVAL; } kvm_pmu_vcpu_reset(vcpu); vcpu->arch.pmu.ready = true; return 0; } static int kvm_arm_pmu_v3_init(struct kvm_vcpu *vcpu) { if (!kvm_arm_support_pmu_v3()) return -ENODEV; if (!test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features)) return -ENXIO; if (vcpu->arch.pmu.created) return -EBUSY; if (irqchip_in_kernel(vcpu->kvm)) { int ret; /* * If using the PMU with an in-kernel virtual GIC * implementation, we require the GIC to be already * initialized when initializing the PMU. */ if (!vgic_initialized(vcpu->kvm)) return -ENODEV; if (!kvm_arm_pmu_irq_initialized(vcpu)) return -ENXIO; ret = kvm_vgic_set_owner(vcpu, vcpu->arch.pmu.irq_num, &vcpu->arch.pmu); if (ret) return ret; } vcpu->arch.pmu.created = true; return 0; } /* * For one VM the interrupt type must be same for each vcpu. * As a PPI, the interrupt number is the same for all vcpus, * while as an SPI it must be a separate number per vcpu. */ static bool pmu_irq_is_valid(struct kvm *kvm, int irq) { int i; struct kvm_vcpu *vcpu; kvm_for_each_vcpu(i, vcpu, kvm) { if (!kvm_arm_pmu_irq_initialized(vcpu)) continue; if (irq_is_ppi(irq)) { if (vcpu->arch.pmu.irq_num != irq) return false; } else { if (vcpu->arch.pmu.irq_num == irq) return false; } } return true; } int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) { switch (attr->attr) { case KVM_ARM_VCPU_PMU_V3_IRQ: { int __user *uaddr = (int __user *)(long)attr->addr; int irq; if (!irqchip_in_kernel(vcpu->kvm)) return -EINVAL; if (!test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features)) return -ENODEV; if (get_user(irq, uaddr)) return -EFAULT; /* The PMU overflow interrupt can be a PPI or a valid SPI. */ if (!(irq_is_ppi(irq) || irq_is_spi(irq))) return -EINVAL; if (!pmu_irq_is_valid(vcpu->kvm, irq)) return -EINVAL; if (kvm_arm_pmu_irq_initialized(vcpu)) return -EBUSY; kvm_debug("Set kvm ARM PMU irq: %d\n", irq); vcpu->arch.pmu.irq_num = irq; return 0; } case KVM_ARM_VCPU_PMU_V3_INIT: return kvm_arm_pmu_v3_init(vcpu); } return -ENXIO; } int kvm_arm_pmu_v3_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) { switch (attr->attr) { case KVM_ARM_VCPU_PMU_V3_IRQ: { int __user *uaddr = (int __user *)(long)attr->addr; int irq; if (!irqchip_in_kernel(vcpu->kvm)) return -EINVAL; if (!test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features)) return -ENODEV; if (!kvm_arm_pmu_irq_initialized(vcpu)) return -ENXIO; irq = vcpu->arch.pmu.irq_num; return put_user(irq, uaddr); } } return -ENXIO; } int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) { switch (attr->attr) { case KVM_ARM_VCPU_PMU_V3_IRQ: case KVM_ARM_VCPU_PMU_V3_INIT: if (kvm_arm_support_pmu_v3() && test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features)) return 0; } return -ENXIO; }