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Diffstat (limited to '')
| -rw-r--r-- | arch/x86/kvm/vmx/pmu_intel.c | 814 |
1 files changed, 814 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c new file mode 100644 index 000000000..9a75a0d5d --- /dev/null +++ b/arch/x86/kvm/vmx/pmu_intel.c @@ -0,0 +1,814 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * KVM PMU support for Intel CPUs + * + * Copyright 2011 Red Hat, Inc. and/or its affiliates. + * + * Authors: + * Avi Kivity <avi@redhat.com> + * Gleb Natapov <gleb@redhat.com> + */ +#include <linux/types.h> +#include <linux/kvm_host.h> +#include <linux/perf_event.h> +#include <asm/perf_event.h> +#include "x86.h" +#include "cpuid.h" +#include "lapic.h" +#include "nested.h" +#include "pmu.h" + +#define MSR_PMC_FULL_WIDTH_BIT (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0) + +static struct kvm_event_hw_type_mapping intel_arch_events[] = { + [0] = { 0x3c, 0x00, PERF_COUNT_HW_CPU_CYCLES }, + [1] = { 0xc0, 0x00, PERF_COUNT_HW_INSTRUCTIONS }, + [2] = { 0x3c, 0x01, PERF_COUNT_HW_BUS_CYCLES }, + [3] = { 0x2e, 0x4f, PERF_COUNT_HW_CACHE_REFERENCES }, + [4] = { 0x2e, 0x41, PERF_COUNT_HW_CACHE_MISSES }, + [5] = { 0xc4, 0x00, PERF_COUNT_HW_BRANCH_INSTRUCTIONS }, + [6] = { 0xc5, 0x00, PERF_COUNT_HW_BRANCH_MISSES }, + /* The above index must match CPUID 0x0A.EBX bit vector */ + [7] = { 0x00, 0x03, PERF_COUNT_HW_REF_CPU_CYCLES }, +}; + +/* mapping between fixed pmc index and intel_arch_events array */ +static int fixed_pmc_events[] = {1, 0, 7}; + +static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data) +{ + struct kvm_pmc *pmc; + u8 old_fixed_ctr_ctrl = pmu->fixed_ctr_ctrl; + int i; + + pmu->fixed_ctr_ctrl = data; + for (i = 0; i < pmu->nr_arch_fixed_counters; i++) { + u8 new_ctrl = fixed_ctrl_field(data, i); + u8 old_ctrl = fixed_ctrl_field(old_fixed_ctr_ctrl, i); + + if (old_ctrl == new_ctrl) + continue; + + pmc = get_fixed_pmc(pmu, MSR_CORE_PERF_FIXED_CTR0 + i); + + __set_bit(INTEL_PMC_IDX_FIXED + i, pmu->pmc_in_use); + reprogram_counter(pmc); + } +} + +static struct kvm_pmc *intel_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx) +{ + if (pmc_idx < INTEL_PMC_IDX_FIXED) { + return get_gp_pmc(pmu, MSR_P6_EVNTSEL0 + pmc_idx, + MSR_P6_EVNTSEL0); + } else { + u32 idx = pmc_idx - INTEL_PMC_IDX_FIXED; + + return get_fixed_pmc(pmu, idx + MSR_CORE_PERF_FIXED_CTR0); + } +} + +static void reprogram_counters(struct kvm_pmu *pmu, u64 diff) +{ + int bit; + struct kvm_pmc *pmc; + + for_each_set_bit(bit, (unsigned long *)&diff, X86_PMC_IDX_MAX) { + pmc = intel_pmc_idx_to_pmc(pmu, bit); + if (pmc) + reprogram_counter(pmc); + } +} + +static bool intel_hw_event_available(struct kvm_pmc *pmc) +{ + struct kvm_pmu *pmu = pmc_to_pmu(pmc); + u8 event_select = pmc->eventsel & ARCH_PERFMON_EVENTSEL_EVENT; + u8 unit_mask = (pmc->eventsel & ARCH_PERFMON_EVENTSEL_UMASK) >> 8; + int i; + + for (i = 0; i < ARRAY_SIZE(intel_arch_events); i++) { + if (intel_arch_events[i].eventsel != event_select || + intel_arch_events[i].unit_mask != unit_mask) + continue; + + /* disable event that reported as not present by cpuid */ + if ((i < 7) && !(pmu->available_event_types & (1 << i))) + return false; + + break; + } + + return true; +} + +/* check if a PMC is enabled by comparing it with globl_ctrl bits. */ +static bool intel_pmc_is_enabled(struct kvm_pmc *pmc) +{ + struct kvm_pmu *pmu = pmc_to_pmu(pmc); + + if (!intel_pmu_has_perf_global_ctrl(pmu)) + return true; + + return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl); +} + +static bool intel_is_valid_rdpmc_ecx(struct kvm_vcpu *vcpu, unsigned int idx) +{ + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + bool fixed = idx & (1u << 30); + + idx &= ~(3u << 30); + + return fixed ? idx < pmu->nr_arch_fixed_counters + : idx < pmu->nr_arch_gp_counters; +} + +static struct kvm_pmc *intel_rdpmc_ecx_to_pmc(struct kvm_vcpu *vcpu, + unsigned int idx, u64 *mask) +{ + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + bool fixed = idx & (1u << 30); + struct kvm_pmc *counters; + unsigned int num_counters; + + idx &= ~(3u << 30); + if (fixed) { + counters = pmu->fixed_counters; + num_counters = pmu->nr_arch_fixed_counters; + } else { + counters = pmu->gp_counters; + num_counters = pmu->nr_arch_gp_counters; + } + if (idx >= num_counters) + return NULL; + *mask &= pmu->counter_bitmask[fixed ? KVM_PMC_FIXED : KVM_PMC_GP]; + return &counters[array_index_nospec(idx, num_counters)]; +} + +static inline u64 vcpu_get_perf_capabilities(struct kvm_vcpu *vcpu) +{ + if (!guest_cpuid_has(vcpu, X86_FEATURE_PDCM)) + return 0; + + return vcpu->arch.perf_capabilities; +} + +static inline bool fw_writes_is_enabled(struct kvm_vcpu *vcpu) +{ + return (vcpu_get_perf_capabilities(vcpu) & PMU_CAP_FW_WRITES) != 0; +} + +static inline struct kvm_pmc *get_fw_gp_pmc(struct kvm_pmu *pmu, u32 msr) +{ + if (!fw_writes_is_enabled(pmu_to_vcpu(pmu))) + return NULL; + + return get_gp_pmc(pmu, msr, MSR_IA32_PMC0); +} + +static bool intel_pmu_is_valid_lbr_msr(struct kvm_vcpu *vcpu, u32 index) +{ + struct x86_pmu_lbr *records = vcpu_to_lbr_records(vcpu); + bool ret = false; + + if (!intel_pmu_lbr_is_enabled(vcpu)) + return ret; + + ret = (index == MSR_LBR_SELECT) || (index == MSR_LBR_TOS) || + (index >= records->from && index < records->from + records->nr) || + (index >= records->to && index < records->to + records->nr); + + if (!ret && records->info) + ret = (index >= records->info && index < records->info + records->nr); + + return ret; +} + +static bool intel_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr) +{ + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + u64 perf_capabilities; + int ret; + + switch (msr) { + case MSR_CORE_PERF_FIXED_CTR_CTRL: + case MSR_CORE_PERF_GLOBAL_STATUS: + case MSR_CORE_PERF_GLOBAL_CTRL: + case MSR_CORE_PERF_GLOBAL_OVF_CTRL: + return intel_pmu_has_perf_global_ctrl(pmu); + break; + case MSR_IA32_PEBS_ENABLE: + ret = vcpu_get_perf_capabilities(vcpu) & PERF_CAP_PEBS_FORMAT; + break; + case MSR_IA32_DS_AREA: + ret = guest_cpuid_has(vcpu, X86_FEATURE_DS); + break; + case MSR_PEBS_DATA_CFG: + perf_capabilities = vcpu_get_perf_capabilities(vcpu); + ret = (perf_capabilities & PERF_CAP_PEBS_BASELINE) && + ((perf_capabilities & PERF_CAP_PEBS_FORMAT) > 3); + break; + default: + ret = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0) || + get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0) || + get_fixed_pmc(pmu, msr) || get_fw_gp_pmc(pmu, msr) || + intel_pmu_is_valid_lbr_msr(vcpu, msr); + break; + } + + return ret; +} + +static struct kvm_pmc *intel_msr_idx_to_pmc(struct kvm_vcpu *vcpu, u32 msr) +{ + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + struct kvm_pmc *pmc; + + pmc = get_fixed_pmc(pmu, msr); + pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0); + pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0); + + return pmc; +} + +static inline void intel_pmu_release_guest_lbr_event(struct kvm_vcpu *vcpu) +{ + struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu); + + if (lbr_desc->event) { + perf_event_release_kernel(lbr_desc->event); + lbr_desc->event = NULL; + vcpu_to_pmu(vcpu)->event_count--; + } +} + +int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu) +{ + struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu); + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + struct perf_event *event; + + /* + * The perf_event_attr is constructed in the minimum efficient way: + * - set 'pinned = true' to make it task pinned so that if another + * cpu pinned event reclaims LBR, the event->oncpu will be set to -1; + * - set '.exclude_host = true' to record guest branches behavior; + * + * - set '.config = INTEL_FIXED_VLBR_EVENT' to indicates host perf + * schedule the event without a real HW counter but a fake one; + * check is_guest_lbr_event() and __intel_get_event_constraints(); + * + * - set 'sample_type = PERF_SAMPLE_BRANCH_STACK' and + * 'branch_sample_type = PERF_SAMPLE_BRANCH_CALL_STACK | + * PERF_SAMPLE_BRANCH_USER' to configure it as a LBR callstack + * event, which helps KVM to save/restore guest LBR records + * during host context switches and reduces quite a lot overhead, + * check branch_user_callstack() and intel_pmu_lbr_sched_task(); + */ + struct perf_event_attr attr = { + .type = PERF_TYPE_RAW, + .size = sizeof(attr), + .config = INTEL_FIXED_VLBR_EVENT, + .sample_type = PERF_SAMPLE_BRANCH_STACK, + .pinned = true, + .exclude_host = true, + .branch_sample_type = PERF_SAMPLE_BRANCH_CALL_STACK | + PERF_SAMPLE_BRANCH_USER, + }; + + if (unlikely(lbr_desc->event)) { + __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use); + return 0; + } + + event = perf_event_create_kernel_counter(&attr, -1, + current, NULL, NULL); + if (IS_ERR(event)) { + pr_debug_ratelimited("%s: failed %ld\n", + __func__, PTR_ERR(event)); + return PTR_ERR(event); + } + lbr_desc->event = event; + pmu->event_count++; + __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use); + return 0; +} + +/* + * It's safe to access LBR msrs from guest when they have not + * been passthrough since the host would help restore or reset + * the LBR msrs records when the guest LBR event is scheduled in. + */ +static bool intel_pmu_handle_lbr_msrs_access(struct kvm_vcpu *vcpu, + struct msr_data *msr_info, bool read) +{ + struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu); + u32 index = msr_info->index; + + if (!intel_pmu_is_valid_lbr_msr(vcpu, index)) + return false; + + if (!lbr_desc->event && intel_pmu_create_guest_lbr_event(vcpu) < 0) + goto dummy; + + /* + * Disable irq to ensure the LBR feature doesn't get reclaimed by the + * host at the time the value is read from the msr, and this avoids the + * host LBR value to be leaked to the guest. If LBR has been reclaimed, + * return 0 on guest reads. + */ + local_irq_disable(); + if (lbr_desc->event->state == PERF_EVENT_STATE_ACTIVE) { + if (read) + rdmsrl(index, msr_info->data); + else + wrmsrl(index, msr_info->data); + __set_bit(INTEL_PMC_IDX_FIXED_VLBR, vcpu_to_pmu(vcpu)->pmc_in_use); + local_irq_enable(); + return true; + } + clear_bit(INTEL_PMC_IDX_FIXED_VLBR, vcpu_to_pmu(vcpu)->pmc_in_use); + local_irq_enable(); + +dummy: + if (read) + msr_info->data = 0; + return true; +} + +static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) +{ + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + struct kvm_pmc *pmc; + u32 msr = msr_info->index; + + switch (msr) { + case MSR_CORE_PERF_FIXED_CTR_CTRL: + msr_info->data = pmu->fixed_ctr_ctrl; + return 0; + case MSR_CORE_PERF_GLOBAL_STATUS: + msr_info->data = pmu->global_status; + return 0; + case MSR_CORE_PERF_GLOBAL_CTRL: + msr_info->data = pmu->global_ctrl; + return 0; + case MSR_CORE_PERF_GLOBAL_OVF_CTRL: + msr_info->data = 0; + return 0; + case MSR_IA32_PEBS_ENABLE: + msr_info->data = pmu->pebs_enable; + return 0; + case MSR_IA32_DS_AREA: + msr_info->data = pmu->ds_area; + return 0; + case MSR_PEBS_DATA_CFG: + msr_info->data = pmu->pebs_data_cfg; + return 0; + default: + if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) || + (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) { + u64 val = pmc_read_counter(pmc); + msr_info->data = + val & pmu->counter_bitmask[KVM_PMC_GP]; + return 0; + } else if ((pmc = get_fixed_pmc(pmu, msr))) { + u64 val = pmc_read_counter(pmc); + msr_info->data = + val & pmu->counter_bitmask[KVM_PMC_FIXED]; + return 0; + } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) { + msr_info->data = pmc->eventsel; + return 0; + } else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, true)) + return 0; + } + + return 1; +} + +static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) +{ + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + struct kvm_pmc *pmc; + u32 msr = msr_info->index; + u64 data = msr_info->data; + u64 reserved_bits, diff; + + switch (msr) { + case MSR_CORE_PERF_FIXED_CTR_CTRL: + if (pmu->fixed_ctr_ctrl == data) + return 0; + if (!(data & pmu->fixed_ctr_ctrl_mask)) { + reprogram_fixed_counters(pmu, data); + return 0; + } + break; + case MSR_CORE_PERF_GLOBAL_STATUS: + if (msr_info->host_initiated) { + pmu->global_status = data; + return 0; + } + break; /* RO MSR */ + case MSR_CORE_PERF_GLOBAL_CTRL: + if (pmu->global_ctrl == data) + return 0; + if (kvm_valid_perf_global_ctrl(pmu, data)) { + diff = pmu->global_ctrl ^ data; + pmu->global_ctrl = data; + reprogram_counters(pmu, diff); + return 0; + } + break; + case MSR_CORE_PERF_GLOBAL_OVF_CTRL: + if (!(data & pmu->global_ovf_ctrl_mask)) { + if (!msr_info->host_initiated) + pmu->global_status &= ~data; + return 0; + } + break; + case MSR_IA32_PEBS_ENABLE: + if (pmu->pebs_enable == data) + return 0; + if (!(data & pmu->pebs_enable_mask)) { + diff = pmu->pebs_enable ^ data; + pmu->pebs_enable = data; + reprogram_counters(pmu, diff); + return 0; + } + break; + case MSR_IA32_DS_AREA: + if (msr_info->host_initiated && data && !guest_cpuid_has(vcpu, X86_FEATURE_DS)) + return 1; + if (is_noncanonical_address(data, vcpu)) + return 1; + pmu->ds_area = data; + return 0; + case MSR_PEBS_DATA_CFG: + if (pmu->pebs_data_cfg == data) + return 0; + if (!(data & pmu->pebs_data_cfg_mask)) { + pmu->pebs_data_cfg = data; + return 0; + } + break; + default: + if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) || + (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) { + if ((msr & MSR_PMC_FULL_WIDTH_BIT) && + (data & ~pmu->counter_bitmask[KVM_PMC_GP])) + return 1; + if (!msr_info->host_initiated && + !(msr & MSR_PMC_FULL_WIDTH_BIT)) + data = (s64)(s32)data; + pmc_write_counter(pmc, data); + pmc_update_sample_period(pmc); + return 0; + } else if ((pmc = get_fixed_pmc(pmu, msr))) { + pmc_write_counter(pmc, data); + pmc_update_sample_period(pmc); + return 0; + } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) { + if (data == pmc->eventsel) + return 0; + reserved_bits = pmu->reserved_bits; + if ((pmc->idx == 2) && + (pmu->raw_event_mask & HSW_IN_TX_CHECKPOINTED)) + reserved_bits ^= HSW_IN_TX_CHECKPOINTED; + if (!(data & reserved_bits)) { + pmc->eventsel = data; + reprogram_counter(pmc); + return 0; + } + } else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, false)) + return 0; + } + + return 1; +} + +static void setup_fixed_pmc_eventsel(struct kvm_pmu *pmu) +{ + size_t size = ARRAY_SIZE(fixed_pmc_events); + struct kvm_pmc *pmc; + u32 event; + int i; + + for (i = 0; i < pmu->nr_arch_fixed_counters; i++) { + pmc = &pmu->fixed_counters[i]; + event = fixed_pmc_events[array_index_nospec(i, size)]; + pmc->eventsel = (intel_arch_events[event].unit_mask << 8) | + intel_arch_events[event].eventsel; + } +} + +static void intel_pmu_refresh(struct kvm_vcpu *vcpu) +{ + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu); + struct kvm_cpuid_entry2 *entry; + union cpuid10_eax eax; + union cpuid10_edx edx; + u64 perf_capabilities; + u64 counter_mask; + int i; + + pmu->nr_arch_gp_counters = 0; + pmu->nr_arch_fixed_counters = 0; + pmu->counter_bitmask[KVM_PMC_GP] = 0; + pmu->counter_bitmask[KVM_PMC_FIXED] = 0; + pmu->version = 0; + pmu->reserved_bits = 0xffffffff00200000ull; + pmu->raw_event_mask = X86_RAW_EVENT_MASK; + pmu->global_ctrl_mask = ~0ull; + pmu->global_ovf_ctrl_mask = ~0ull; + pmu->fixed_ctr_ctrl_mask = ~0ull; + pmu->pebs_enable_mask = ~0ull; + pmu->pebs_data_cfg_mask = ~0ull; + + entry = kvm_find_cpuid_entry(vcpu, 0xa); + if (!entry || !vcpu->kvm->arch.enable_pmu) + return; + eax.full = entry->eax; + edx.full = entry->edx; + + pmu->version = eax.split.version_id; + if (!pmu->version) + return; + + pmu->nr_arch_gp_counters = min_t(int, eax.split.num_counters, + kvm_pmu_cap.num_counters_gp); + eax.split.bit_width = min_t(int, eax.split.bit_width, + kvm_pmu_cap.bit_width_gp); + pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << eax.split.bit_width) - 1; + eax.split.mask_length = min_t(int, eax.split.mask_length, + kvm_pmu_cap.events_mask_len); + pmu->available_event_types = ~entry->ebx & + ((1ull << eax.split.mask_length) - 1); + + if (pmu->version == 1) { + pmu->nr_arch_fixed_counters = 0; + } else { + pmu->nr_arch_fixed_counters = + min3(ARRAY_SIZE(fixed_pmc_events), + (size_t) edx.split.num_counters_fixed, + (size_t)kvm_pmu_cap.num_counters_fixed); + edx.split.bit_width_fixed = min_t(int, edx.split.bit_width_fixed, + kvm_pmu_cap.bit_width_fixed); + pmu->counter_bitmask[KVM_PMC_FIXED] = + ((u64)1 << edx.split.bit_width_fixed) - 1; + setup_fixed_pmc_eventsel(pmu); + } + + for (i = 0; i < pmu->nr_arch_fixed_counters; i++) + pmu->fixed_ctr_ctrl_mask &= ~(0xbull << (i * 4)); + counter_mask = ~(((1ull << pmu->nr_arch_gp_counters) - 1) | + (((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED)); + pmu->global_ctrl_mask = counter_mask; + pmu->global_ovf_ctrl_mask = pmu->global_ctrl_mask + & ~(MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF | + MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD); + if (vmx_pt_mode_is_host_guest()) + pmu->global_ovf_ctrl_mask &= + ~MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI; + + entry = kvm_find_cpuid_entry_index(vcpu, 7, 0); + if (entry && + (boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM)) && + (entry->ebx & (X86_FEATURE_HLE|X86_FEATURE_RTM))) { + pmu->reserved_bits ^= HSW_IN_TX; + pmu->raw_event_mask |= (HSW_IN_TX|HSW_IN_TX_CHECKPOINTED); + } + + bitmap_set(pmu->all_valid_pmc_idx, + 0, pmu->nr_arch_gp_counters); + bitmap_set(pmu->all_valid_pmc_idx, + INTEL_PMC_MAX_GENERIC, pmu->nr_arch_fixed_counters); + + perf_capabilities = vcpu_get_perf_capabilities(vcpu); + if (cpuid_model_is_consistent(vcpu) && + (perf_capabilities & PMU_CAP_LBR_FMT)) + x86_perf_get_lbr(&lbr_desc->records); + else + lbr_desc->records.nr = 0; + + if (lbr_desc->records.nr) + bitmap_set(pmu->all_valid_pmc_idx, INTEL_PMC_IDX_FIXED_VLBR, 1); + + if (perf_capabilities & PERF_CAP_PEBS_FORMAT) { + if (perf_capabilities & PERF_CAP_PEBS_BASELINE) { + pmu->pebs_enable_mask = counter_mask; + pmu->reserved_bits &= ~ICL_EVENTSEL_ADAPTIVE; + for (i = 0; i < pmu->nr_arch_fixed_counters; i++) { + pmu->fixed_ctr_ctrl_mask &= + ~(1ULL << (INTEL_PMC_IDX_FIXED + i * 4)); + } + pmu->pebs_data_cfg_mask = ~0xff00000full; + } else { + pmu->pebs_enable_mask = + ~((1ull << pmu->nr_arch_gp_counters) - 1); + } + } +} + +static void intel_pmu_init(struct kvm_vcpu *vcpu) +{ + int i; + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu); + + for (i = 0; i < KVM_INTEL_PMC_MAX_GENERIC; i++) { + pmu->gp_counters[i].type = KVM_PMC_GP; + pmu->gp_counters[i].vcpu = vcpu; + pmu->gp_counters[i].idx = i; + pmu->gp_counters[i].current_config = 0; + } + + for (i = 0; i < KVM_PMC_MAX_FIXED; i++) { + pmu->fixed_counters[i].type = KVM_PMC_FIXED; + pmu->fixed_counters[i].vcpu = vcpu; + pmu->fixed_counters[i].idx = i + INTEL_PMC_IDX_FIXED; + pmu->fixed_counters[i].current_config = 0; + } + + vcpu->arch.perf_capabilities = kvm_caps.supported_perf_cap; + lbr_desc->records.nr = 0; + lbr_desc->event = NULL; + lbr_desc->msr_passthrough = false; +} + +static void intel_pmu_reset(struct kvm_vcpu *vcpu) +{ + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + struct kvm_pmc *pmc = NULL; + int i; + + for (i = 0; i < KVM_INTEL_PMC_MAX_GENERIC; i++) { + pmc = &pmu->gp_counters[i]; + + pmc_stop_counter(pmc); + pmc->counter = pmc->eventsel = 0; + } + + for (i = 0; i < KVM_PMC_MAX_FIXED; i++) { + pmc = &pmu->fixed_counters[i]; + + pmc_stop_counter(pmc); + pmc->counter = 0; + } + + pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status = 0; + + intel_pmu_release_guest_lbr_event(vcpu); +} + +/* + * Emulate LBR_On_PMI behavior for 1 < pmu.version < 4. + * + * If Freeze_LBR_On_PMI = 1, the LBR is frozen on PMI and + * the KVM emulates to clear the LBR bit (bit 0) in IA32_DEBUGCTL. + * + * Guest needs to re-enable LBR to resume branches recording. + */ +static void intel_pmu_legacy_freezing_lbrs_on_pmi(struct kvm_vcpu *vcpu) +{ + u64 data = vmcs_read64(GUEST_IA32_DEBUGCTL); + + if (data & DEBUGCTLMSR_FREEZE_LBRS_ON_PMI) { + data &= ~DEBUGCTLMSR_LBR; + vmcs_write64(GUEST_IA32_DEBUGCTL, data); + } +} + +static void intel_pmu_deliver_pmi(struct kvm_vcpu *vcpu) +{ + u8 version = vcpu_to_pmu(vcpu)->version; + + if (!intel_pmu_lbr_is_enabled(vcpu)) + return; + + if (version > 1 && version < 4) + intel_pmu_legacy_freezing_lbrs_on_pmi(vcpu); +} + +static void vmx_update_intercept_for_lbr_msrs(struct kvm_vcpu *vcpu, bool set) +{ + struct x86_pmu_lbr *lbr = vcpu_to_lbr_records(vcpu); + int i; + + for (i = 0; i < lbr->nr; i++) { + vmx_set_intercept_for_msr(vcpu, lbr->from + i, MSR_TYPE_RW, set); + vmx_set_intercept_for_msr(vcpu, lbr->to + i, MSR_TYPE_RW, set); + if (lbr->info) + vmx_set_intercept_for_msr(vcpu, lbr->info + i, MSR_TYPE_RW, set); + } + + vmx_set_intercept_for_msr(vcpu, MSR_LBR_SELECT, MSR_TYPE_RW, set); + vmx_set_intercept_for_msr(vcpu, MSR_LBR_TOS, MSR_TYPE_RW, set); +} + +static inline void vmx_disable_lbr_msrs_passthrough(struct kvm_vcpu *vcpu) +{ + struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu); + + if (!lbr_desc->msr_passthrough) + return; + + vmx_update_intercept_for_lbr_msrs(vcpu, true); + lbr_desc->msr_passthrough = false; +} + +static inline void vmx_enable_lbr_msrs_passthrough(struct kvm_vcpu *vcpu) +{ + struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu); + + if (lbr_desc->msr_passthrough) + return; + + vmx_update_intercept_for_lbr_msrs(vcpu, false); + lbr_desc->msr_passthrough = true; +} + +/* + * Higher priority host perf events (e.g. cpu pinned) could reclaim the + * pmu resources (e.g. LBR) that were assigned to the guest. This is + * usually done via ipi calls (more details in perf_install_in_context). + * + * Before entering the non-root mode (with irq disabled here), double + * confirm that the pmu features enabled to the guest are not reclaimed + * by higher priority host events. Otherwise, disallow vcpu's access to + * the reclaimed features. + */ +void vmx_passthrough_lbr_msrs(struct kvm_vcpu *vcpu) +{ + struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); + struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu); + + if (!lbr_desc->event) { + vmx_disable_lbr_msrs_passthrough(vcpu); + if (vmcs_read64(GUEST_IA32_DEBUGCTL) & DEBUGCTLMSR_LBR) + goto warn; + if (test_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use)) + goto warn; + return; + } + + if (lbr_desc->event->state < PERF_EVENT_STATE_ACTIVE) { + vmx_disable_lbr_msrs_passthrough(vcpu); + __clear_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use); + goto warn; + } else + vmx_enable_lbr_msrs_passthrough(vcpu); + + return; + +warn: + pr_warn_ratelimited("kvm: vcpu-%d: fail to passthrough LBR.\n", + vcpu->vcpu_id); +} + +static void intel_pmu_cleanup(struct kvm_vcpu *vcpu) +{ + if (!(vmcs_read64(GUEST_IA32_DEBUGCTL) & DEBUGCTLMSR_LBR)) + intel_pmu_release_guest_lbr_event(vcpu); +} + +void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu) +{ + struct kvm_pmc *pmc = NULL; + int bit, hw_idx; + + for_each_set_bit(bit, (unsigned long *)&pmu->global_ctrl, + X86_PMC_IDX_MAX) { + pmc = intel_pmc_idx_to_pmc(pmu, bit); + + if (!pmc || !pmc_speculative_in_use(pmc) || + !intel_pmc_is_enabled(pmc) || !pmc->perf_event) + continue; + + /* + * A negative index indicates the event isn't mapped to a + * physical counter in the host, e.g. due to contention. + */ + hw_idx = pmc->perf_event->hw.idx; + if (hw_idx != pmc->idx && hw_idx > -1) + pmu->host_cross_mapped_mask |= BIT_ULL(hw_idx); + } +} + +struct kvm_pmu_ops intel_pmu_ops __initdata = { + .hw_event_available = intel_hw_event_available, + .pmc_is_enabled = intel_pmc_is_enabled, + .pmc_idx_to_pmc = intel_pmc_idx_to_pmc, + .rdpmc_ecx_to_pmc = intel_rdpmc_ecx_to_pmc, + .msr_idx_to_pmc = intel_msr_idx_to_pmc, + .is_valid_rdpmc_ecx = intel_is_valid_rdpmc_ecx, + .is_valid_msr = intel_is_valid_msr, + .get_msr = intel_pmu_get_msr, + .set_msr = intel_pmu_set_msr, + .refresh = intel_pmu_refresh, + .init = intel_pmu_init, + .reset = intel_pmu_reset, + .deliver_pmi = intel_pmu_deliver_pmi, + .cleanup = intel_pmu_cleanup, +}; |