// 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>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#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 {
u8 eventsel;
u8 unit_mask;
} const intel_arch_events[] = {
[0] = { 0x3c, 0x00 },
[1] = { 0xc0, 0x00 },
[2] = { 0x3c, 0x01 },
[3] = { 0x2e, 0x4f },
[4] = { 0x2e, 0x41 },
[5] = { 0xc4, 0x00 },
[6] = { 0xc5, 0x00 },
/* The above index must match CPUID 0x0A.EBX bit vector */
[7] = { 0x00, 0x03 },
};
/* 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);
kvm_pmu_request_counter_reprogram(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;
if (!diff)
return;
for_each_set_bit(bit, (unsigned long *)&diff, X86_PMC_IDX_MAX)
set_bit(bit, pmu->reprogram_pmi);
kvm_make_request(KVM_REQ_PMU, pmu_to_vcpu(pmu));
}
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;
break;
case MSR_CORE_PERF_GLOBAL_STATUS:
msr_info->data = pmu->global_status;
break;
case MSR_CORE_PERF_GLOBAL_CTRL:
msr_info->data = pmu->global_ctrl;
break;
case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
msr_info->data = 0;
break;
case MSR_IA32_PEBS_ENABLE:
msr_info->data = pmu->pebs_enable;
break;
case MSR_IA32_DS_AREA:
msr_info->data = pmu->ds_area;
break;
case MSR_PEBS_DATA_CFG:
msr_info->data = pmu->pebs_data_cfg;
break;
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];
break;
} else if ((pmc = get_fixed_pmc(pmu, msr))) {
u64 val = pmc_read_counter(pmc);
msr_info->data =
val & pmu->counter_bitmask[KVM_PMC_FIXED];
break;
} else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
msr_info->data = pmc->eventsel;
break;
} else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, true)) {
break;
}
return 1;
}
return 0;
}
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 (data & pmu->fixed_ctr_ctrl_mask)
return 1;
if (pmu->fixed_ctr_ctrl != data)
reprogram_fixed_counters(pmu, data);
break;
case MSR_CORE_PERF_GLOBAL_STATUS:
if (!msr_info->host_initiated)
return 1; /* RO MSR */
pmu->global_status = data;
break;
case MSR_CORE_PERF_GLOBAL_CTRL:
if (!kvm_valid_perf_global_ctrl(pmu, data))
return 1;
if (pmu->global_ctrl != data) {
diff = pmu->global_ctrl ^ data;
pmu->global_ctrl = data;
reprogram_counters(pmu, diff);
}
break;
case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
if (data & pmu->global_ovf_ctrl_mask)
return 1;
if (!msr_info->host_initiated)
pmu->global_status &= ~data;
break;
case MSR_IA32_PEBS_ENABLE:
if (data & pmu->pebs_enable_mask)
return 1;
if (pmu->pebs_enable != data) {
diff = pmu->pebs_enable ^ data;
pmu->pebs_enable = data;
reprogram_counters(pmu, diff);
}
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;
break;
case MSR_PEBS_DATA_CFG:
if (data & pmu->pebs_data_cfg_mask)
return 1;
pmu->pebs_data_cfg = data;
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->counter += data - pmc_read_counter(pmc);
pmc_update_sample_period(pmc);
break;
} else if ((pmc = get_fixed_pmc(pmu, msr))) {
pmc->counter += data - pmc_read_counter(pmc);
pmc_update_sample_period(pmc);
break;
} else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
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)
return 1;
if (data != pmc->eventsel) {
pmc->eventsel = data;
kvm_pmu_request_counter_reprogram(pmc);
}
break;
} else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, false)) {
break;
}
/* Not a known PMU MSR. */
return 1;
}
return 0;
}
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;
memset(&lbr_desc->records, 0, sizeof(lbr_desc->records));
/*
* Setting passthrough of LBR MSRs is done only in the VM-Entry loop,
* and PMU refresh is disallowed after the vCPU has run, i.e. this code
* should never be reached while KVM is passing through MSRs.
*/
if (KVM_BUG_ON(lbr_desc->msr_passthrough, vcpu->kvm))
return;
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;
}
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->prev_counter = pmc->eventsel = 0;
}
for (i = 0; i < KVM_PMC_MAX_FIXED; i++) {
pmc = &pmu->fixed_counters[i];
pmc_stop_counter(pmc);
pmc->counter = pmc->prev_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("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,
.EVENTSEL_EVENT = ARCH_PERFMON_EVENTSEL_EVENT,
.MAX_NR_GP_COUNTERS = KVM_INTEL_PMC_MAX_GENERIC,
};
