A lot of functions in pmu-emul.c aren't specific to the emulated PMU implementation. Move them to the more appropriate pmu.c file where shared PMU functions should live.
Signed-off-by: Colton Lewis coltonlewis@google.com --- arch/arm64/include/asm/kvm_host.h | 2 + arch/arm64/kvm/pmu-emul.c | 611 +----------------------------- arch/arm64/kvm/pmu.c | 610 +++++++++++++++++++++++++++++ 3 files changed, 613 insertions(+), 610 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index f5d97cd8e177..3482d7602a5b 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -1706,6 +1706,7 @@ int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu); struct kvm_pmu_events *kvm_get_pmu_events(void); void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu); void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu); +bool kvm_pmu_overflow_status(struct kvm_vcpu *vcpu);
/* * Updates the vcpu's view of the pmu events for this cpu. @@ -1719,6 +1720,7 @@ void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu); } while (0)
u8 kvm_arm_pmu_get_pmuver_limit(void); +u32 kvm_pmu_event_mask(struct kvm *kvm); u64 kvm_pmu_evtyper_mask(struct kvm *kvm); int kvm_arm_set_default_pmu(struct kvm *kvm); u8 kvm_arm_pmu_get_max_counters(struct kvm *kvm); diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 472a2ab6938f..ff86c66e1b48 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -16,21 +16,10 @@
#define PERF_ATTR_CFG1_COUNTER_64BIT BIT(0)
-static LIST_HEAD(arm_pmus); -static DEFINE_MUTEX(arm_pmus_lock); - static void kvm_pmu_create_perf_event(struct kvm_pmc *pmc); static void kvm_pmu_release_perf_event(struct kvm_pmc *pmc); static bool kvm_pmu_counter_is_enabled(struct kvm_pmc *pmc);
-#define kvm_arm_pmu_irq_initialized(v) ((v)->arch.pmu.irq_num >= VGIC_NR_SGIS) - -bool kvm_supports_guest_pmuv3(void) -{ - guard(mutex)(&arm_pmus_lock); - return !list_empty(&arm_pmus); -} - static struct kvm_vcpu *kvm_pmc_to_vcpu(const struct kvm_pmc *pmc) { return container_of(pmc, struct kvm_vcpu, arch.pmu.pmc[pmc->idx]); @@ -41,46 +30,6 @@ static struct kvm_pmc *kvm_vcpu_idx_to_pmc(struct kvm_vcpu *vcpu, int cnt_idx) return &vcpu->arch.pmu.pmc[cnt_idx]; }
-static u32 __kvm_pmu_event_mask(unsigned int pmuver) -{ - switch (pmuver) { - case ID_AA64DFR0_EL1_PMUVer_IMP: - return GENMASK(9, 0); - case ID_AA64DFR0_EL1_PMUVer_V3P1: - case ID_AA64DFR0_EL1_PMUVer_V3P4: - case ID_AA64DFR0_EL1_PMUVer_V3P5: - case ID_AA64DFR0_EL1_PMUVer_V3P7: - return GENMASK(15, 0); - default: /* Shouldn't be here, just for sanity */ - WARN_ONCE(1, "Unknown PMU version %d\n", pmuver); - return 0; - } -} - -static u32 kvm_pmu_event_mask(struct kvm *kvm) -{ - u64 dfr0 = kvm_read_vm_id_reg(kvm, SYS_ID_AA64DFR0_EL1); - u8 pmuver = SYS_FIELD_GET(ID_AA64DFR0_EL1, PMUVer, dfr0); - - return __kvm_pmu_event_mask(pmuver); -} - -u64 kvm_pmu_evtyper_mask(struct kvm *kvm) -{ - u64 mask = ARMV8_PMU_EXCLUDE_EL1 | ARMV8_PMU_EXCLUDE_EL0 | - kvm_pmu_event_mask(kvm); - - if (kvm_has_feat(kvm, ID_AA64PFR0_EL1, EL2, IMP)) - mask |= ARMV8_PMU_INCLUDE_EL2; - - if (kvm_has_feat(kvm, ID_AA64PFR0_EL1, EL3, IMP)) - mask |= ARMV8_PMU_EXCLUDE_NS_EL0 | - ARMV8_PMU_EXCLUDE_NS_EL1 | - ARMV8_PMU_EXCLUDE_EL3; - - return mask; -} - /** * kvm_pmc_is_64bit - determine if counter is 64bit * @pmc: counter context @@ -371,7 +320,7 @@ void kvm_pmu_reprogram_counter_mask(struct kvm_vcpu *vcpu, u64 val) * counter where the values of the global enable control, PMOVSSET_EL0[n], and * PMINTENSET_EL1[n] are all 1. */ -static bool kvm_pmu_overflow_status(struct kvm_vcpu *vcpu) +bool kvm_pmu_overflow_status(struct kvm_vcpu *vcpu) { u64 reg = __vcpu_sys_reg(vcpu, PMOVSSET_EL0);
@@ -394,24 +343,6 @@ static bool kvm_pmu_overflow_status(struct kvm_vcpu *vcpu) return reg; }
-static void kvm_pmu_update_state(struct kvm_vcpu *vcpu) -{ - struct kvm_pmu *pmu = &vcpu->arch.pmu; - bool overflow; - - 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, - 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; @@ -437,43 +368,6 @@ void kvm_pmu_update_run(struct kvm_vcpu *vcpu) 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); -} - -/* - * When perf interrupt is an NMI, we cannot safely notify the vcpu corresponding - * to the event. - * This is why we need a callback to do it once outside of the NMI context. - */ -static void kvm_pmu_perf_overflow_notify_vcpu(struct irq_work *work) -{ - struct kvm_vcpu *vcpu; - - vcpu = container_of(work, struct kvm_vcpu, arch.pmu.overflow_work); - kvm_vcpu_kick(vcpu); -} - /* * Perform an increment on any of the counters described in @mask, * generating the overflow if required, and propagate it as a chained @@ -785,137 +679,6 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, kvm_pmu_create_perf_event(pmc); }
-struct arm_pmu_entry { - struct list_head entry; - struct arm_pmu *arm_pmu; -}; - -void kvm_host_pmu_init(struct arm_pmu *pmu) -{ - struct arm_pmu_entry *entry; - - /* - * Check the sanitised PMU version for the system, as KVM does not - * support implementations where PMUv3 exists on a subset of CPUs. - */ - if (!pmuv3_implemented(kvm_arm_pmu_get_pmuver_limit())) - return; - - guard(mutex)(&arm_pmus_lock); - - entry = kmalloc(sizeof(*entry), GFP_KERNEL); - if (!entry) - return; - - entry->arm_pmu = pmu; - list_add_tail(&entry->entry, &arm_pmus); -} - -static struct arm_pmu *kvm_pmu_probe_armpmu(void) -{ - struct arm_pmu_entry *entry; - struct arm_pmu *pmu; - int cpu; - - guard(mutex)(&arm_pmus_lock); - - /* - * It is safe to use a stale cpu to iterate the list of PMUs so long as - * the same value is used for the entirety of the loop. Given this, and - * the fact that no percpu data is used for the lookup there is no need - * to disable preemption. - * - * It is still necessary to get a valid cpu, though, to probe for the - * default PMU instance as userspace is not required to specify a PMU - * type. In order to uphold the preexisting behavior KVM selects the - * PMU instance for the core during vcpu init. A dependent use - * case would be a user with disdain of all things big.LITTLE that - * affines the VMM to a particular cluster of cores. - * - * In any case, userspace should just do the sane thing and use the UAPI - * to select a PMU type directly. But, be wary of the baggage being - * carried here. - */ - cpu = raw_smp_processor_id(); - list_for_each_entry(entry, &arm_pmus, entry) { - pmu = entry->arm_pmu; - - if (cpumask_test_cpu(cpu, &pmu->supported_cpus)) - return pmu; - } - - return NULL; -} - -static u64 __compute_pmceid(struct arm_pmu *pmu, bool pmceid1) -{ - u32 hi[2], lo[2]; - - bitmap_to_arr32(lo, pmu->pmceid_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS); - bitmap_to_arr32(hi, pmu->pmceid_ext_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS); - - return ((u64)hi[pmceid1] << 32) | lo[pmceid1]; -} - -static u64 compute_pmceid0(struct arm_pmu *pmu) -{ - u64 val = __compute_pmceid(pmu, 0); - - /* always support SW_INCR */ - val |= BIT(ARMV8_PMUV3_PERFCTR_SW_INCR); - /* always support CHAIN */ - val |= BIT(ARMV8_PMUV3_PERFCTR_CHAIN); - return val; -} - -static u64 compute_pmceid1(struct arm_pmu *pmu) -{ - u64 val = __compute_pmceid(pmu, 1); - - /* - * Don't advertise STALL_SLOT*, as PMMIR_EL0 is handled - * as RAZ - */ - val &= ~(BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32) | - BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_FRONTEND - 32) | - BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_BACKEND - 32)); - return val; -} - -u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) -{ - struct arm_pmu *cpu_pmu = vcpu->kvm->arch.arm_pmu; - unsigned long *bmap = vcpu->kvm->arch.pmu_filter; - u64 val, mask = 0; - int base, i, nr_events; - - if (!pmceid1) { - val = compute_pmceid0(cpu_pmu); - base = 0; - } else { - val = compute_pmceid1(cpu_pmu); - base = 32; - } - - if (!bmap) - return val; - - nr_events = kvm_pmu_event_mask(vcpu->kvm) + 1; - - for (i = 0; i < 32; i += 8) { - u64 byte; - - byte = bitmap_get_value8(bmap, base + i); - mask |= byte << i; - if (nr_events >= (0x4000 + base + 32)) { - byte = bitmap_get_value8(bmap, 0x4000 + base + i); - mask |= byte << (32 + i); - } - } - - return val & mask; -} - void kvm_vcpu_reload_pmu(struct kvm_vcpu *vcpu) { u64 mask = kvm_pmu_implemented_counter_mask(vcpu); @@ -927,378 +690,6 @@ void kvm_vcpu_reload_pmu(struct kvm_vcpu *vcpu) kvm_pmu_reprogram_counter_mask(vcpu, mask); }
-int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu) -{ - if (!vcpu->arch.pmu.created) - return -EINVAL; - - /* - * 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 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; - } - - return 0; -} - -static int kvm_arm_pmu_v3_init(struct kvm_vcpu *vcpu) -{ - 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; - } - - init_irq_work(&vcpu->arch.pmu.overflow_work, - kvm_pmu_perf_overflow_notify_vcpu); - - 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) -{ - unsigned long 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; -} - -/** - * kvm_arm_pmu_get_max_counters - Return the max number of PMU counters. - * @kvm: The kvm pointer - */ -u8 kvm_arm_pmu_get_max_counters(struct kvm *kvm) -{ - struct arm_pmu *arm_pmu = kvm->arch.arm_pmu; - - /* - * PMUv3 requires that all event counters are capable of counting any - * event, though the same may not be true of non-PMUv3 hardware. - */ - if (cpus_have_final_cap(ARM64_WORKAROUND_PMUV3_IMPDEF_TRAPS)) - return 1; - - /* - * The arm_pmu->cntr_mask considers the fixed counter(s) as well. - * Ignore those and return only the general-purpose counters. - */ - return bitmap_weight(arm_pmu->cntr_mask, ARMV8_PMU_MAX_GENERAL_COUNTERS); -} - -static void kvm_arm_set_nr_counters(struct kvm *kvm, unsigned int nr) -{ - kvm->arch.nr_pmu_counters = nr; - - /* Reset MDCR_EL2.HPMN behind the vcpus' back... */ - if (test_bit(KVM_ARM_VCPU_HAS_EL2, kvm->arch.vcpu_features)) { - struct kvm_vcpu *vcpu; - unsigned long i; - - kvm_for_each_vcpu(i, vcpu, kvm) { - u64 val = __vcpu_sys_reg(vcpu, MDCR_EL2); - val &= ~MDCR_EL2_HPMN; - val |= FIELD_PREP(MDCR_EL2_HPMN, kvm->arch.nr_pmu_counters); - __vcpu_sys_reg(vcpu, MDCR_EL2) = val; - } - } -} - -static void kvm_arm_set_pmu(struct kvm *kvm, struct arm_pmu *arm_pmu) -{ - lockdep_assert_held(&kvm->arch.config_lock); - - kvm->arch.arm_pmu = arm_pmu; - kvm_arm_set_nr_counters(kvm, kvm_arm_pmu_get_max_counters(kvm)); -} - -/** - * kvm_arm_set_default_pmu - No PMU set, get the default one. - * @kvm: The kvm pointer - * - * The observant among you will notice that the supported_cpus - * mask does not get updated for the default PMU even though it - * is quite possible the selected instance supports only a - * subset of cores in the system. This is intentional, and - * upholds the preexisting behavior on heterogeneous systems - * where vCPUs can be scheduled on any core but the guest - * counters could stop working. - */ -int kvm_arm_set_default_pmu(struct kvm *kvm) -{ - struct arm_pmu *arm_pmu = kvm_pmu_probe_armpmu(); - - if (!arm_pmu) - return -ENODEV; - - kvm_arm_set_pmu(kvm, arm_pmu); - return 0; -} - -static int kvm_arm_pmu_v3_set_pmu(struct kvm_vcpu *vcpu, int pmu_id) -{ - struct kvm *kvm = vcpu->kvm; - struct arm_pmu_entry *entry; - struct arm_pmu *arm_pmu; - int ret = -ENXIO; - - lockdep_assert_held(&kvm->arch.config_lock); - mutex_lock(&arm_pmus_lock); - - list_for_each_entry(entry, &arm_pmus, entry) { - arm_pmu = entry->arm_pmu; - if (arm_pmu->pmu.type == pmu_id) { - if (kvm_vm_has_ran_once(kvm) || - (kvm->arch.pmu_filter && kvm->arch.arm_pmu != arm_pmu)) { - ret = -EBUSY; - break; - } - - kvm_arm_set_pmu(kvm, arm_pmu); - cpumask_copy(kvm->arch.supported_cpus, &arm_pmu->supported_cpus); - ret = 0; - break; - } - } - - mutex_unlock(&arm_pmus_lock); - return ret; -} - -static int kvm_arm_pmu_v3_set_nr_counters(struct kvm_vcpu *vcpu, unsigned int n) -{ - struct kvm *kvm = vcpu->kvm; - - if (!kvm->arch.arm_pmu) - return -EINVAL; - - if (n > kvm_arm_pmu_get_max_counters(kvm)) - return -EINVAL; - - kvm_arm_set_nr_counters(kvm, n); - return 0; -} - -int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) -{ - struct kvm *kvm = vcpu->kvm; - - lockdep_assert_held(&kvm->arch.config_lock); - - if (!kvm_vcpu_has_pmu(vcpu)) - return -ENODEV; - - if (vcpu->arch.pmu.created) - return -EBUSY; - - switch (attr->attr) { - case KVM_ARM_VCPU_PMU_V3_IRQ: { - int __user *uaddr = (int __user *)(long)attr->addr; - int irq; - - if (!irqchip_in_kernel(kvm)) - return -EINVAL; - - 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(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_FILTER: { - u8 pmuver = kvm_arm_pmu_get_pmuver_limit(); - struct kvm_pmu_event_filter __user *uaddr; - struct kvm_pmu_event_filter filter; - int nr_events; - - /* - * Allow userspace to specify an event filter for the entire - * event range supported by PMUVer of the hardware, rather - * than the guest's PMUVer for KVM backward compatibility. - */ - nr_events = __kvm_pmu_event_mask(pmuver) + 1; - - uaddr = (struct kvm_pmu_event_filter __user *)(long)attr->addr; - - if (copy_from_user(&filter, uaddr, sizeof(filter))) - return -EFAULT; - - if (((u32)filter.base_event + filter.nevents) > nr_events || - (filter.action != KVM_PMU_EVENT_ALLOW && - filter.action != KVM_PMU_EVENT_DENY)) - return -EINVAL; - - if (kvm_vm_has_ran_once(kvm)) - return -EBUSY; - - if (!kvm->arch.pmu_filter) { - kvm->arch.pmu_filter = bitmap_alloc(nr_events, GFP_KERNEL_ACCOUNT); - if (!kvm->arch.pmu_filter) - return -ENOMEM; - - /* - * The default depends on the first applied filter. - * If it allows events, the default is to deny. - * Conversely, if the first filter denies a set of - * events, the default is to allow. - */ - if (filter.action == KVM_PMU_EVENT_ALLOW) - bitmap_zero(kvm->arch.pmu_filter, nr_events); - else - bitmap_fill(kvm->arch.pmu_filter, nr_events); - } - - if (filter.action == KVM_PMU_EVENT_ALLOW) - bitmap_set(kvm->arch.pmu_filter, filter.base_event, filter.nevents); - else - bitmap_clear(kvm->arch.pmu_filter, filter.base_event, filter.nevents); - - return 0; - } - case KVM_ARM_VCPU_PMU_V3_SET_PMU: { - int __user *uaddr = (int __user *)(long)attr->addr; - int pmu_id; - - if (get_user(pmu_id, uaddr)) - return -EFAULT; - - return kvm_arm_pmu_v3_set_pmu(vcpu, pmu_id); - } - case KVM_ARM_VCPU_PMU_V3_SET_NR_COUNTERS: { - unsigned int __user *uaddr = (unsigned int __user *)(long)attr->addr; - unsigned int n; - - if (get_user(n, uaddr)) - return -EFAULT; - - return kvm_arm_pmu_v3_set_nr_counters(vcpu, n); - } - 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 (!kvm_vcpu_has_pmu(vcpu)) - 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: - case KVM_ARM_VCPU_PMU_V3_FILTER: - case KVM_ARM_VCPU_PMU_V3_SET_PMU: - case KVM_ARM_VCPU_PMU_V3_SET_NR_COUNTERS: - if (kvm_vcpu_has_pmu(vcpu)) - return 0; - } - - return -ENXIO; -} - -u8 kvm_arm_pmu_get_pmuver_limit(void) -{ - unsigned int pmuver; - - pmuver = SYS_FIELD_GET(ID_AA64DFR0_EL1, PMUVer, - read_sanitised_ftr_reg(SYS_ID_AA64DFR0_EL1)); - - /* - * Spoof a barebones PMUv3 implementation if the system supports IMPDEF - * traps of the PMUv3 sysregs - */ - if (cpus_have_final_cap(ARM64_WORKAROUND_PMUV3_IMPDEF_TRAPS)) - return ID_AA64DFR0_EL1_PMUVer_IMP; - - /* - * Otherwise, treat IMPLEMENTATION DEFINED functionality as - * unimplemented - */ - if (pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF) - return 0; - - return min(pmuver, ID_AA64DFR0_EL1_PMUVer_V3P5); -} - /** * kvm_vcpu_read_pmcr - Read PMCR_EL0 register for the vCPU * @vcpu: The vcpu pointer diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c index 8bfc6b0a85f6..4f0152e67ff3 100644 --- a/arch/arm64/kvm/pmu.c +++ b/arch/arm64/kvm/pmu.c @@ -8,10 +8,21 @@ #include <linux/perf/arm_pmu.h> #include <linux/perf/arm_pmuv3.h>
+#include <asm/kvm_emulate.h> #include <asm/kvm_pmu.h>
+static LIST_HEAD(arm_pmus); +static DEFINE_MUTEX(arm_pmus_lock); static DEFINE_PER_CPU(struct kvm_pmu_events, kvm_pmu_events);
+#define kvm_arm_pmu_irq_initialized(v) ((v)->arch.pmu.irq_num >= VGIC_NR_SGIS) + +bool kvm_supports_guest_pmuv3(void) +{ + guard(mutex)(&arm_pmus_lock); + return !list_empty(&arm_pmus); +} + /* * Given the perf event attributes and system type, determine * if we are going to need to switch counters at guest entry/exit. @@ -211,3 +222,602 @@ void kvm_vcpu_pmu_resync_el0(void)
kvm_make_request(KVM_REQ_RESYNC_PMU_EL0, vcpu); } + +struct arm_pmu_entry { + struct list_head entry; + struct arm_pmu *arm_pmu; +}; + +void kvm_host_pmu_init(struct arm_pmu *pmu) +{ + struct arm_pmu_entry *entry; + + /* + * Check the sanitised PMU version for the system, as KVM does not + * support implementations where PMUv3 exists on a subset of CPUs. + */ + if (!pmuv3_implemented(kvm_arm_pmu_get_pmuver_limit())) + return; + + guard(mutex)(&arm_pmus_lock); + + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return; + + entry->arm_pmu = pmu; + list_add_tail(&entry->entry, &arm_pmus); +} + +static struct arm_pmu *kvm_pmu_probe_armpmu(void) +{ + struct arm_pmu_entry *entry; + struct arm_pmu *pmu; + int cpu; + + guard(mutex)(&arm_pmus_lock); + + /* + * It is safe to use a stale cpu to iterate the list of PMUs so long as + * the same value is used for the entirety of the loop. Given this, and + * the fact that no percpu data is used for the lookup there is no need + * to disable preemption. + * + * It is still necessary to get a valid cpu, though, to probe for the + * default PMU instance as userspace is not required to specify a PMU + * type. In order to uphold the preexisting behavior KVM selects the + * PMU instance for the core during vcpu init. A dependent use + * case would be a user with disdain of all things big.LITTLE that + * affines the VMM to a particular cluster of cores. + * + * In any case, userspace should just do the sane thing and use the UAPI + * to select a PMU type directly. But, be wary of the baggage being + * carried here. + */ + cpu = raw_smp_processor_id(); + list_for_each_entry(entry, &arm_pmus, entry) { + pmu = entry->arm_pmu; + + if (cpumask_test_cpu(cpu, &pmu->supported_cpus)) + return pmu; + } + + return NULL; +} + +static u64 __compute_pmceid(struct arm_pmu *pmu, bool pmceid1) +{ + u32 hi[2], lo[2]; + + bitmap_to_arr32(lo, pmu->pmceid_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS); + bitmap_to_arr32(hi, pmu->pmceid_ext_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS); + + return ((u64)hi[pmceid1] << 32) | lo[pmceid1]; +} + +static u64 compute_pmceid0(struct arm_pmu *pmu) +{ + u64 val = __compute_pmceid(pmu, 0); + + /* always support SW_INCR */ + val |= BIT(ARMV8_PMUV3_PERFCTR_SW_INCR); + /* always support CHAIN */ + val |= BIT(ARMV8_PMUV3_PERFCTR_CHAIN); + return val; +} + +static u64 compute_pmceid1(struct arm_pmu *pmu) +{ + u64 val = __compute_pmceid(pmu, 1); + + /* + * Don't advertise STALL_SLOT*, as PMMIR_EL0 is handled + * as RAZ + */ + val &= ~(BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32) | + BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_FRONTEND - 32) | + BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_BACKEND - 32)); + return val; +} + +u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) +{ + struct arm_pmu *cpu_pmu = vcpu->kvm->arch.arm_pmu; + unsigned long *bmap = vcpu->kvm->arch.pmu_filter; + u64 val, mask = 0; + int base, i, nr_events; + + if (!pmceid1) { + val = compute_pmceid0(cpu_pmu); + base = 0; + } else { + val = compute_pmceid1(cpu_pmu); + base = 32; + } + + if (!bmap) + return val; + + nr_events = kvm_pmu_event_mask(vcpu->kvm) + 1; + + for (i = 0; i < 32; i += 8) { + u64 byte; + + byte = bitmap_get_value8(bmap, base + i); + mask |= byte << i; + if (nr_events >= (0x4000 + base + 32)) { + byte = bitmap_get_value8(bmap, 0x4000 + base + i); + mask |= byte << (32 + i); + } + } + + return val & mask; +} + +/* + * When perf interrupt is an NMI, we cannot safely notify the vcpu corresponding + * to the event. + * This is why we need a callback to do it once outside of the NMI context. + */ +static void kvm_pmu_perf_overflow_notify_vcpu(struct irq_work *work) +{ + struct kvm_vcpu *vcpu; + + vcpu = container_of(work, struct kvm_vcpu, arch.pmu.overflow_work); + kvm_vcpu_kick(vcpu); +} + +static u32 __kvm_pmu_event_mask(unsigned int pmuver) +{ + switch (pmuver) { + case ID_AA64DFR0_EL1_PMUVer_IMP: + return GENMASK(9, 0); + case ID_AA64DFR0_EL1_PMUVer_V3P1: + case ID_AA64DFR0_EL1_PMUVer_V3P4: + case ID_AA64DFR0_EL1_PMUVer_V3P5: + case ID_AA64DFR0_EL1_PMUVer_V3P7: + return GENMASK(15, 0); + default: /* Shouldn't be here, just for sanity */ + WARN_ONCE(1, "Unknown PMU version %d\n", pmuver); + return 0; + } +} + +u32 kvm_pmu_event_mask(struct kvm *kvm) +{ + u64 dfr0 = kvm_read_vm_id_reg(kvm, SYS_ID_AA64DFR0_EL1); + u8 pmuver = SYS_FIELD_GET(ID_AA64DFR0_EL1, PMUVer, dfr0); + + return __kvm_pmu_event_mask(pmuver); +} + +u64 kvm_pmu_evtyper_mask(struct kvm *kvm) +{ + u64 mask = ARMV8_PMU_EXCLUDE_EL1 | ARMV8_PMU_EXCLUDE_EL0 | + kvm_pmu_event_mask(kvm); + + if (kvm_has_feat(kvm, ID_AA64PFR0_EL1, EL2, IMP)) + mask |= ARMV8_PMU_INCLUDE_EL2; + + if (kvm_has_feat(kvm, ID_AA64PFR0_EL1, EL3, IMP)) + mask |= ARMV8_PMU_EXCLUDE_NS_EL0 | + ARMV8_PMU_EXCLUDE_NS_EL1 | + ARMV8_PMU_EXCLUDE_EL3; + + return mask; +} + +static void kvm_pmu_update_state(struct kvm_vcpu *vcpu) +{ + struct kvm_pmu *pmu = &vcpu->arch.pmu; + bool overflow; + + 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, + pmu->irq_num, overflow, pmu); + WARN_ON(ret); + } +} + +/** + * 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); +} + +int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu) +{ + if (!vcpu->arch.pmu.created) + return -EINVAL; + + /* + * 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 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; + } + + return 0; +} + +static int kvm_arm_pmu_v3_init(struct kvm_vcpu *vcpu) +{ + 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; + } + + init_irq_work(&vcpu->arch.pmu.overflow_work, + kvm_pmu_perf_overflow_notify_vcpu); + + 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) +{ + unsigned long 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; +} + +/** + * kvm_arm_pmu_get_max_counters - Return the max number of PMU counters. + * @kvm: The kvm pointer + */ +u8 kvm_arm_pmu_get_max_counters(struct kvm *kvm) +{ + struct arm_pmu *arm_pmu = kvm->arch.arm_pmu; + + /* + * PMUv3 requires that all event counters are capable of counting any + * event, though the same may not be true of non-PMUv3 hardware. + */ + if (cpus_have_final_cap(ARM64_WORKAROUND_PMUV3_IMPDEF_TRAPS)) + return 1; + + /* + * The arm_pmu->cntr_mask considers the fixed counter(s) as well. + * Ignore those and return only the general-purpose counters. + */ + return bitmap_weight(arm_pmu->cntr_mask, ARMV8_PMU_MAX_GENERAL_COUNTERS); +} + +static void kvm_arm_set_nr_counters(struct kvm *kvm, unsigned int nr) +{ + kvm->arch.nr_pmu_counters = nr; + + /* Reset MDCR_EL2.HPMN behind the vcpus' back... */ + if (test_bit(KVM_ARM_VCPU_HAS_EL2, kvm->arch.vcpu_features)) { + struct kvm_vcpu *vcpu; + unsigned long i; + + kvm_for_each_vcpu(i, vcpu, kvm) { + u64 val = __vcpu_sys_reg(vcpu, MDCR_EL2); + + val &= ~MDCR_EL2_HPMN; + val |= FIELD_PREP(MDCR_EL2_HPMN, kvm->arch.nr_pmu_counters); + __vcpu_sys_reg(vcpu, MDCR_EL2) = val; + } + } +} + +static void kvm_arm_set_pmu(struct kvm *kvm, struct arm_pmu *arm_pmu) +{ + lockdep_assert_held(&kvm->arch.config_lock); + + kvm->arch.arm_pmu = arm_pmu; + kvm_arm_set_nr_counters(kvm, kvm_arm_pmu_get_max_counters(kvm)); +} + +/** + * kvm_arm_set_default_pmu - No PMU set, get the default one. + * @kvm: The kvm pointer + * + * The observant among you will notice that the supported_cpus + * mask does not get updated for the default PMU even though it + * is quite possible the selected instance supports only a + * subset of cores in the system. This is intentional, and + * upholds the preexisting behavior on heterogeneous systems + * where vCPUs can be scheduled on any core but the guest + * counters could stop working. + */ +int kvm_arm_set_default_pmu(struct kvm *kvm) +{ + struct arm_pmu *arm_pmu = kvm_pmu_probe_armpmu(); + + if (!arm_pmu) + return -ENODEV; + + kvm_arm_set_pmu(kvm, arm_pmu); + return 0; +} + +static int kvm_arm_pmu_v3_set_pmu(struct kvm_vcpu *vcpu, int pmu_id) +{ + struct kvm *kvm = vcpu->kvm; + struct arm_pmu_entry *entry; + struct arm_pmu *arm_pmu; + int ret = -ENXIO; + + lockdep_assert_held(&kvm->arch.config_lock); + mutex_lock(&arm_pmus_lock); + + list_for_each_entry(entry, &arm_pmus, entry) { + arm_pmu = entry->arm_pmu; + if (arm_pmu->pmu.type == pmu_id) { + if (kvm_vm_has_ran_once(kvm) || + (kvm->arch.pmu_filter && kvm->arch.arm_pmu != arm_pmu)) { + ret = -EBUSY; + break; + } + + kvm_arm_set_pmu(kvm, arm_pmu); + cpumask_copy(kvm->arch.supported_cpus, &arm_pmu->supported_cpus); + ret = 0; + break; + } + } + + mutex_unlock(&arm_pmus_lock); + return ret; +} + +static int kvm_arm_pmu_v3_set_nr_counters(struct kvm_vcpu *vcpu, unsigned int n) +{ + struct kvm *kvm = vcpu->kvm; + + if (!kvm->arch.arm_pmu) + return -EINVAL; + + if (n > kvm_arm_pmu_get_max_counters(kvm)) + return -EINVAL; + + kvm_arm_set_nr_counters(kvm, n); + return 0; +} + +int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) +{ + struct kvm *kvm = vcpu->kvm; + + lockdep_assert_held(&kvm->arch.config_lock); + + if (!kvm_vcpu_has_pmu(vcpu)) + return -ENODEV; + + if (vcpu->arch.pmu.created) + return -EBUSY; + + switch (attr->attr) { + case KVM_ARM_VCPU_PMU_V3_IRQ: { + int __user *uaddr = (int __user *)(long)attr->addr; + int irq; + + if (!irqchip_in_kernel(kvm)) + return -EINVAL; + + 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(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_FILTER: { + u8 pmuver = kvm_arm_pmu_get_pmuver_limit(); + struct kvm_pmu_event_filter __user *uaddr; + struct kvm_pmu_event_filter filter; + int nr_events; + + /* + * Allow userspace to specify an event filter for the entire + * event range supported by PMUVer of the hardware, rather + * than the guest's PMUVer for KVM backward compatibility. + */ + nr_events = __kvm_pmu_event_mask(pmuver) + 1; + + uaddr = (struct kvm_pmu_event_filter __user *)(long)attr->addr; + + if (copy_from_user(&filter, uaddr, sizeof(filter))) + return -EFAULT; + + if (((u32)filter.base_event + filter.nevents) > nr_events || + (filter.action != KVM_PMU_EVENT_ALLOW && + filter.action != KVM_PMU_EVENT_DENY)) + return -EINVAL; + + if (kvm_vm_has_ran_once(kvm)) + return -EBUSY; + + if (!kvm->arch.pmu_filter) { + kvm->arch.pmu_filter = bitmap_alloc(nr_events, GFP_KERNEL_ACCOUNT); + if (!kvm->arch.pmu_filter) + return -ENOMEM; + + /* + * The default depends on the first applied filter. + * If it allows events, the default is to deny. + * Conversely, if the first filter denies a set of + * events, the default is to allow. + */ + if (filter.action == KVM_PMU_EVENT_ALLOW) + bitmap_zero(kvm->arch.pmu_filter, nr_events); + else + bitmap_fill(kvm->arch.pmu_filter, nr_events); + } + + if (filter.action == KVM_PMU_EVENT_ALLOW) + bitmap_set(kvm->arch.pmu_filter, filter.base_event, filter.nevents); + else + bitmap_clear(kvm->arch.pmu_filter, filter.base_event, filter.nevents); + + return 0; + } + case KVM_ARM_VCPU_PMU_V3_SET_PMU: { + int __user *uaddr = (int __user *)(long)attr->addr; + int pmu_id; + + if (get_user(pmu_id, uaddr)) + return -EFAULT; + + return kvm_arm_pmu_v3_set_pmu(vcpu, pmu_id); + } + case KVM_ARM_VCPU_PMU_V3_SET_NR_COUNTERS: { + unsigned int __user *uaddr = (unsigned int __user *)(long)attr->addr; + unsigned int n; + + if (get_user(n, uaddr)) + return -EFAULT; + + return kvm_arm_pmu_v3_set_nr_counters(vcpu, n); + } + 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 (!kvm_vcpu_has_pmu(vcpu)) + 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: + case KVM_ARM_VCPU_PMU_V3_FILTER: + case KVM_ARM_VCPU_PMU_V3_SET_PMU: + case KVM_ARM_VCPU_PMU_V3_SET_NR_COUNTERS: + if (kvm_vcpu_has_pmu(vcpu)) + return 0; + } + + return -ENXIO; +} + +u8 kvm_arm_pmu_get_pmuver_limit(void) +{ + unsigned int pmuver; + + pmuver = SYS_FIELD_GET(ID_AA64DFR0_EL1, PMUVer, + read_sanitised_ftr_reg(SYS_ID_AA64DFR0_EL1)); + + /* + * Spoof a barebones PMUv3 implementation if the system supports IMPDEF + * traps of the PMUv3 sysregs + */ + if (cpus_have_final_cap(ARM64_WORKAROUND_PMUV3_IMPDEF_TRAPS)) + return ID_AA64DFR0_EL1_PMUVer_IMP; + + /* + * Otherwise, treat IMPLEMENTATION DEFINED functionality as + * unimplemented + */ + if (pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF) + return 0; + + return min(pmuver, ID_AA64DFR0_EL1_PMUVer_V3P5); +}