diff options
Diffstat (limited to 'arch/x86/kvm/pmu.c')
-rw-r--r-- | arch/x86/kvm/pmu.c | 91 |
1 files changed, 83 insertions, 8 deletions
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c index dd745b58ffd8..46875bbd0419 100644 --- a/arch/x86/kvm/pmu.c +++ b/arch/x86/kvm/pmu.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Kernel-based Virtual Machine -- Performance Monitoring Unit support * @@ -7,10 +8,6 @@ * Avi Kivity <avi@redhat.com> * Gleb Natapov <gleb@redhat.com> * Wei Huang <wei@redhat.com> - * - * This work is licensed under the terms of the GNU GPL, version 2. See - * the COPYING file in the top-level directory. - * */ #include <linux/types.h> @@ -22,6 +19,9 @@ #include "lapic.h" #include "pmu.h" +/* This is enough to filter the vast majority of currently defined events. */ +#define KVM_PMU_EVENT_FILTER_MAX_EVENTS 300 + /* NOTE: * - Each perf counter is defined as "struct kvm_pmc"; * - There are two types of perf counters: general purpose (gp) and fixed. @@ -131,8 +131,8 @@ static void pmc_reprogram_counter(struct kvm_pmc *pmc, u32 type, intr ? kvm_perf_overflow_intr : kvm_perf_overflow, pmc); if (IS_ERR(event)) { - printk_once("kvm_pmu: event creation failed %ld\n", - PTR_ERR(event)); + pr_debug_ratelimited("kvm_pmu: event creation failed %ld for pmc->idx = %d\n", + PTR_ERR(event), pmc->idx); return; } @@ -144,6 +144,10 @@ void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel) { unsigned config, type = PERF_TYPE_RAW; u8 event_select, unit_mask; + struct kvm *kvm = pmc->vcpu->kvm; + struct kvm_pmu_event_filter *filter; + int i; + bool allow_event = true; if (eventsel & ARCH_PERFMON_EVENTSEL_PIN_CONTROL) printk_once("kvm pmu: pin control bit is ignored\n"); @@ -155,6 +159,22 @@ void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel) if (!(eventsel & ARCH_PERFMON_EVENTSEL_ENABLE) || !pmc_is_enabled(pmc)) return; + filter = srcu_dereference(kvm->arch.pmu_event_filter, &kvm->srcu); + if (filter) { + for (i = 0; i < filter->nevents; i++) + if (filter->events[i] == + (eventsel & AMD64_RAW_EVENT_MASK_NB)) + break; + if (filter->action == KVM_PMU_EVENT_ALLOW && + i == filter->nevents) + allow_event = false; + if (filter->action == KVM_PMU_EVENT_DENY && + i < filter->nevents) + allow_event = false; + } + if (!allow_event) + return; + event_select = eventsel & ARCH_PERFMON_EVENTSEL_EVENT; unit_mask = (eventsel & ARCH_PERFMON_EVENTSEL_UMASK) >> 8; @@ -186,12 +206,24 @@ void reprogram_fixed_counter(struct kvm_pmc *pmc, u8 ctrl, int idx) { unsigned en_field = ctrl & 0x3; bool pmi = ctrl & 0x8; + struct kvm_pmu_event_filter *filter; + struct kvm *kvm = pmc->vcpu->kvm; pmc_stop_counter(pmc); if (!en_field || !pmc_is_enabled(pmc)) return; + filter = srcu_dereference(kvm->arch.pmu_event_filter, &kvm->srcu); + if (filter) { + if (filter->action == KVM_PMU_EVENT_DENY && + test_bit(idx, (ulong *)&filter->fixed_counter_bitmap)) + return; + if (filter->action == KVM_PMU_EVENT_ALLOW && + !test_bit(idx, (ulong *)&filter->fixed_counter_bitmap)) + return; + } + pmc_reprogram_counter(pmc, PERF_TYPE_HARDWARE, kvm_x86_ops->pmu_ops->find_fixed_event(idx), !(en_field & 0x2), /* exclude user */ @@ -264,10 +296,10 @@ static int kvm_pmu_rdpmc_vmware(struct kvm_vcpu *vcpu, unsigned idx, u64 *data) ctr_val = rdtsc(); break; case VMWARE_BACKDOOR_PMC_REAL_TIME: - ctr_val = ktime_get_boot_ns(); + ctr_val = ktime_get_boottime_ns(); break; case VMWARE_BACKDOOR_PMC_APPARENT_TIME: - ctr_val = ktime_get_boot_ns() + + ctr_val = ktime_get_boottime_ns() + vcpu->kvm->arch.kvmclock_offset; break; default: @@ -351,3 +383,46 @@ void kvm_pmu_destroy(struct kvm_vcpu *vcpu) { kvm_pmu_reset(vcpu); } + +int kvm_vm_ioctl_set_pmu_event_filter(struct kvm *kvm, void __user *argp) +{ + struct kvm_pmu_event_filter tmp, *filter; + size_t size; + int r; + + if (copy_from_user(&tmp, argp, sizeof(tmp))) + return -EFAULT; + + if (tmp.action != KVM_PMU_EVENT_ALLOW && + tmp.action != KVM_PMU_EVENT_DENY) + return -EINVAL; + + if (tmp.flags != 0) + return -EINVAL; + + if (tmp.nevents > KVM_PMU_EVENT_FILTER_MAX_EVENTS) + return -E2BIG; + + size = struct_size(filter, events, tmp.nevents); + filter = kmalloc(size, GFP_KERNEL_ACCOUNT); + if (!filter) + return -ENOMEM; + + r = -EFAULT; + if (copy_from_user(filter, argp, size)) + goto cleanup; + + /* Ensure nevents can't be changed between the user copies. */ + *filter = tmp; + + mutex_lock(&kvm->lock); + rcu_swap_protected(kvm->arch.pmu_event_filter, filter, + mutex_is_locked(&kvm->lock)); + mutex_unlock(&kvm->lock); + + synchronize_srcu_expedited(&kvm->srcu); + r = 0; +cleanup: + kfree(filter); + return r; +} |