// SPDX-License-Identifier: GPL-2.0-only /* * Based on the x86 implementation. * * Copyright (C) 2012 ARM Ltd. * Author: Marc Zyngier <marc.zyngier@arm.com> */ #include <linux/perf_event.h> #include <linux/kvm_host.h> #include <asm/kvm_emulate.h> DEFINE_STATIC_KEY_FALSE(kvm_arm_pmu_available); static int kvm_is_in_guest(void) { return kvm_get_running_vcpu() != NULL; } static int kvm_is_user_mode(void) { struct kvm_vcpu *vcpu; vcpu = kvm_get_running_vcpu(); if (vcpu) return !vcpu_mode_priv(vcpu); return 0; } static unsigned long kvm_get_guest_ip(void) { struct kvm_vcpu *vcpu; vcpu = kvm_get_running_vcpu(); if (vcpu) return *vcpu_pc(vcpu); return 0; } static struct perf_guest_info_callbacks kvm_guest_cbs = { .is_in_guest = kvm_is_in_guest, .is_user_mode = kvm_is_user_mode, .get_guest_ip = kvm_get_guest_ip, }; int kvm_perf_init(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. */ if (IS_ENABLED(CONFIG_ARM_PMU) && perf_num_counters() > 0) static_branch_enable(&kvm_arm_pmu_available); return perf_register_guest_info_callbacks(&kvm_guest_cbs); } int kvm_perf_teardown(void) { return perf_unregister_guest_info_callbacks(&kvm_guest_cbs); }