1 // SPDX-License-Identifier: GPL-2.0-only
3 * KVM PMU support for Intel CPUs
5 * Copyright 2011 Red Hat, Inc. and/or its affiliates.
8 * Avi Kivity <avi@redhat.com>
9 * Gleb Natapov <gleb@redhat.com>
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13 #include <linux/types.h>
14 #include <linux/kvm_host.h>
15 #include <linux/perf_event.h>
16 #include <asm/perf_event.h>
23 #define MSR_PMC_FULL_WIDTH_BIT (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0)
25 enum intel_pmu_architectural_events {
27 * The order of the architectural events matters as support for each
28 * event is enumerated via CPUID using the index of the event.
30 INTEL_ARCH_CPU_CYCLES,
31 INTEL_ARCH_INSTRUCTIONS_RETIRED,
32 INTEL_ARCH_REFERENCE_CYCLES,
33 INTEL_ARCH_LLC_REFERENCES,
34 INTEL_ARCH_LLC_MISSES,
35 INTEL_ARCH_BRANCHES_RETIRED,
36 INTEL_ARCH_BRANCHES_MISPREDICTED,
38 NR_REAL_INTEL_ARCH_EVENTS,
41 * Pseudo-architectural event used to implement IA32_FIXED_CTR2, a.k.a.
42 * TSC reference cycles. The architectural reference cycles event may
43 * or may not actually use the TSC as the reference, e.g. might use the
44 * core crystal clock or the bus clock (yeah, "architectural").
46 PSEUDO_ARCH_REFERENCE_CYCLES = NR_REAL_INTEL_ARCH_EVENTS,
53 } const intel_arch_events[] = {
54 [INTEL_ARCH_CPU_CYCLES] = { 0x3c, 0x00 },
55 [INTEL_ARCH_INSTRUCTIONS_RETIRED] = { 0xc0, 0x00 },
56 [INTEL_ARCH_REFERENCE_CYCLES] = { 0x3c, 0x01 },
57 [INTEL_ARCH_LLC_REFERENCES] = { 0x2e, 0x4f },
58 [INTEL_ARCH_LLC_MISSES] = { 0x2e, 0x41 },
59 [INTEL_ARCH_BRANCHES_RETIRED] = { 0xc4, 0x00 },
60 [INTEL_ARCH_BRANCHES_MISPREDICTED] = { 0xc5, 0x00 },
61 [PSEUDO_ARCH_REFERENCE_CYCLES] = { 0x00, 0x03 },
64 /* mapping between fixed pmc index and intel_arch_events array */
65 static int fixed_pmc_events[] = {
66 [0] = INTEL_ARCH_INSTRUCTIONS_RETIRED,
67 [1] = INTEL_ARCH_CPU_CYCLES,
68 [2] = PSEUDO_ARCH_REFERENCE_CYCLES,
71 static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
74 u64 old_fixed_ctr_ctrl = pmu->fixed_ctr_ctrl;
77 pmu->fixed_ctr_ctrl = data;
78 for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
79 u8 new_ctrl = fixed_ctrl_field(data, i);
80 u8 old_ctrl = fixed_ctrl_field(old_fixed_ctr_ctrl, i);
82 if (old_ctrl == new_ctrl)
85 pmc = get_fixed_pmc(pmu, MSR_CORE_PERF_FIXED_CTR0 + i);
87 __set_bit(INTEL_PMC_IDX_FIXED + i, pmu->pmc_in_use);
88 kvm_pmu_request_counter_reprogram(pmc);
92 static struct kvm_pmc *intel_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx)
94 if (pmc_idx < INTEL_PMC_IDX_FIXED) {
95 return get_gp_pmc(pmu, MSR_P6_EVNTSEL0 + pmc_idx,
98 u32 idx = pmc_idx - INTEL_PMC_IDX_FIXED;
100 return get_fixed_pmc(pmu, idx + MSR_CORE_PERF_FIXED_CTR0);
104 static bool intel_hw_event_available(struct kvm_pmc *pmc)
106 struct kvm_pmu *pmu = pmc_to_pmu(pmc);
107 u8 event_select = pmc->eventsel & ARCH_PERFMON_EVENTSEL_EVENT;
108 u8 unit_mask = (pmc->eventsel & ARCH_PERFMON_EVENTSEL_UMASK) >> 8;
111 BUILD_BUG_ON(ARRAY_SIZE(intel_arch_events) != NR_INTEL_ARCH_EVENTS);
114 * Disallow events reported as unavailable in guest CPUID. Note, this
115 * doesn't apply to pseudo-architectural events.
117 for (i = 0; i < NR_REAL_INTEL_ARCH_EVENTS; i++) {
118 if (intel_arch_events[i].eventsel != event_select ||
119 intel_arch_events[i].unit_mask != unit_mask)
122 return pmu->available_event_types & BIT(i);
128 static bool intel_is_valid_rdpmc_ecx(struct kvm_vcpu *vcpu, unsigned int idx)
130 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
131 bool fixed = idx & (1u << 30);
135 return fixed ? idx < pmu->nr_arch_fixed_counters
136 : idx < pmu->nr_arch_gp_counters;
139 static struct kvm_pmc *intel_rdpmc_ecx_to_pmc(struct kvm_vcpu *vcpu,
140 unsigned int idx, u64 *mask)
142 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
143 bool fixed = idx & (1u << 30);
144 struct kvm_pmc *counters;
145 unsigned int num_counters;
149 counters = pmu->fixed_counters;
150 num_counters = pmu->nr_arch_fixed_counters;
152 counters = pmu->gp_counters;
153 num_counters = pmu->nr_arch_gp_counters;
155 if (idx >= num_counters)
157 *mask &= pmu->counter_bitmask[fixed ? KVM_PMC_FIXED : KVM_PMC_GP];
158 return &counters[array_index_nospec(idx, num_counters)];
161 static inline u64 vcpu_get_perf_capabilities(struct kvm_vcpu *vcpu)
163 if (!guest_cpuid_has(vcpu, X86_FEATURE_PDCM))
166 return vcpu->arch.perf_capabilities;
169 static inline bool fw_writes_is_enabled(struct kvm_vcpu *vcpu)
171 return (vcpu_get_perf_capabilities(vcpu) & PMU_CAP_FW_WRITES) != 0;
174 static inline struct kvm_pmc *get_fw_gp_pmc(struct kvm_pmu *pmu, u32 msr)
176 if (!fw_writes_is_enabled(pmu_to_vcpu(pmu)))
179 return get_gp_pmc(pmu, msr, MSR_IA32_PMC0);
182 static bool intel_pmu_is_valid_lbr_msr(struct kvm_vcpu *vcpu, u32 index)
184 struct x86_pmu_lbr *records = vcpu_to_lbr_records(vcpu);
187 if (!intel_pmu_lbr_is_enabled(vcpu))
190 ret = (index == MSR_LBR_SELECT) || (index == MSR_LBR_TOS) ||
191 (index >= records->from && index < records->from + records->nr) ||
192 (index >= records->to && index < records->to + records->nr);
194 if (!ret && records->info)
195 ret = (index >= records->info && index < records->info + records->nr);
200 static bool intel_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr)
202 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
203 u64 perf_capabilities;
207 case MSR_CORE_PERF_FIXED_CTR_CTRL:
208 return kvm_pmu_has_perf_global_ctrl(pmu);
209 case MSR_IA32_PEBS_ENABLE:
210 ret = vcpu_get_perf_capabilities(vcpu) & PERF_CAP_PEBS_FORMAT;
212 case MSR_IA32_DS_AREA:
213 ret = guest_cpuid_has(vcpu, X86_FEATURE_DS);
215 case MSR_PEBS_DATA_CFG:
216 perf_capabilities = vcpu_get_perf_capabilities(vcpu);
217 ret = (perf_capabilities & PERF_CAP_PEBS_BASELINE) &&
218 ((perf_capabilities & PERF_CAP_PEBS_FORMAT) > 3);
221 ret = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0) ||
222 get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0) ||
223 get_fixed_pmc(pmu, msr) || get_fw_gp_pmc(pmu, msr) ||
224 intel_pmu_is_valid_lbr_msr(vcpu, msr);
231 static struct kvm_pmc *intel_msr_idx_to_pmc(struct kvm_vcpu *vcpu, u32 msr)
233 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
236 pmc = get_fixed_pmc(pmu, msr);
237 pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0);
238 pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0);
243 static inline void intel_pmu_release_guest_lbr_event(struct kvm_vcpu *vcpu)
245 struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
247 if (lbr_desc->event) {
248 perf_event_release_kernel(lbr_desc->event);
249 lbr_desc->event = NULL;
250 vcpu_to_pmu(vcpu)->event_count--;
254 int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu)
256 struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
257 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
258 struct perf_event *event;
261 * The perf_event_attr is constructed in the minimum efficient way:
262 * - set 'pinned = true' to make it task pinned so that if another
263 * cpu pinned event reclaims LBR, the event->oncpu will be set to -1;
264 * - set '.exclude_host = true' to record guest branches behavior;
266 * - set '.config = INTEL_FIXED_VLBR_EVENT' to indicates host perf
267 * schedule the event without a real HW counter but a fake one;
268 * check is_guest_lbr_event() and __intel_get_event_constraints();
270 * - set 'sample_type = PERF_SAMPLE_BRANCH_STACK' and
271 * 'branch_sample_type = PERF_SAMPLE_BRANCH_CALL_STACK |
272 * PERF_SAMPLE_BRANCH_USER' to configure it as a LBR callstack
273 * event, which helps KVM to save/restore guest LBR records
274 * during host context switches and reduces quite a lot overhead,
275 * check branch_user_callstack() and intel_pmu_lbr_sched_task();
277 struct perf_event_attr attr = {
278 .type = PERF_TYPE_RAW,
279 .size = sizeof(attr),
280 .config = INTEL_FIXED_VLBR_EVENT,
281 .sample_type = PERF_SAMPLE_BRANCH_STACK,
283 .exclude_host = true,
284 .branch_sample_type = PERF_SAMPLE_BRANCH_CALL_STACK |
285 PERF_SAMPLE_BRANCH_USER,
288 if (unlikely(lbr_desc->event)) {
289 __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
293 event = perf_event_create_kernel_counter(&attr, -1,
294 current, NULL, NULL);
296 pr_debug_ratelimited("%s: failed %ld\n",
297 __func__, PTR_ERR(event));
298 return PTR_ERR(event);
300 lbr_desc->event = event;
302 __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
307 * It's safe to access LBR msrs from guest when they have not
308 * been passthrough since the host would help restore or reset
309 * the LBR msrs records when the guest LBR event is scheduled in.
311 static bool intel_pmu_handle_lbr_msrs_access(struct kvm_vcpu *vcpu,
312 struct msr_data *msr_info, bool read)
314 struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
315 u32 index = msr_info->index;
317 if (!intel_pmu_is_valid_lbr_msr(vcpu, index))
320 if (!lbr_desc->event && intel_pmu_create_guest_lbr_event(vcpu) < 0)
324 * Disable irq to ensure the LBR feature doesn't get reclaimed by the
325 * host at the time the value is read from the msr, and this avoids the
326 * host LBR value to be leaked to the guest. If LBR has been reclaimed,
327 * return 0 on guest reads.
330 if (lbr_desc->event->state == PERF_EVENT_STATE_ACTIVE) {
332 rdmsrl(index, msr_info->data);
334 wrmsrl(index, msr_info->data);
335 __set_bit(INTEL_PMC_IDX_FIXED_VLBR, vcpu_to_pmu(vcpu)->pmc_in_use);
339 clear_bit(INTEL_PMC_IDX_FIXED_VLBR, vcpu_to_pmu(vcpu)->pmc_in_use);
348 static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
350 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
352 u32 msr = msr_info->index;
355 case MSR_CORE_PERF_FIXED_CTR_CTRL:
356 msr_info->data = pmu->fixed_ctr_ctrl;
358 case MSR_IA32_PEBS_ENABLE:
359 msr_info->data = pmu->pebs_enable;
361 case MSR_IA32_DS_AREA:
362 msr_info->data = pmu->ds_area;
364 case MSR_PEBS_DATA_CFG:
365 msr_info->data = pmu->pebs_data_cfg;
368 if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
369 (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) {
370 u64 val = pmc_read_counter(pmc);
372 val & pmu->counter_bitmask[KVM_PMC_GP];
374 } else if ((pmc = get_fixed_pmc(pmu, msr))) {
375 u64 val = pmc_read_counter(pmc);
377 val & pmu->counter_bitmask[KVM_PMC_FIXED];
379 } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
380 msr_info->data = pmc->eventsel;
382 } else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, true)) {
391 static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
393 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
395 u32 msr = msr_info->index;
396 u64 data = msr_info->data;
397 u64 reserved_bits, diff;
400 case MSR_CORE_PERF_FIXED_CTR_CTRL:
401 if (data & pmu->fixed_ctr_ctrl_mask)
404 if (pmu->fixed_ctr_ctrl != data)
405 reprogram_fixed_counters(pmu, data);
407 case MSR_IA32_PEBS_ENABLE:
408 if (data & pmu->pebs_enable_mask)
411 if (pmu->pebs_enable != data) {
412 diff = pmu->pebs_enable ^ data;
413 pmu->pebs_enable = data;
414 reprogram_counters(pmu, diff);
417 case MSR_IA32_DS_AREA:
418 if (is_noncanonical_address(data, vcpu))
423 case MSR_PEBS_DATA_CFG:
424 if (data & pmu->pebs_data_cfg_mask)
427 pmu->pebs_data_cfg = data;
430 if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
431 (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) {
432 if ((msr & MSR_PMC_FULL_WIDTH_BIT) &&
433 (data & ~pmu->counter_bitmask[KVM_PMC_GP]))
436 if (!msr_info->host_initiated &&
437 !(msr & MSR_PMC_FULL_WIDTH_BIT))
438 data = (s64)(s32)data;
439 pmc_write_counter(pmc, data);
441 } else if ((pmc = get_fixed_pmc(pmu, msr))) {
442 pmc_write_counter(pmc, data);
444 } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
445 reserved_bits = pmu->reserved_bits;
446 if ((pmc->idx == 2) &&
447 (pmu->raw_event_mask & HSW_IN_TX_CHECKPOINTED))
448 reserved_bits ^= HSW_IN_TX_CHECKPOINTED;
449 if (data & reserved_bits)
452 if (data != pmc->eventsel) {
453 pmc->eventsel = data;
454 kvm_pmu_request_counter_reprogram(pmc);
457 } else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, false)) {
460 /* Not a known PMU MSR. */
467 static void setup_fixed_pmc_eventsel(struct kvm_pmu *pmu)
471 BUILD_BUG_ON(ARRAY_SIZE(fixed_pmc_events) != KVM_PMC_MAX_FIXED);
473 for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
474 int index = array_index_nospec(i, KVM_PMC_MAX_FIXED);
475 struct kvm_pmc *pmc = &pmu->fixed_counters[index];
476 u32 event = fixed_pmc_events[index];
478 pmc->eventsel = (intel_arch_events[event].unit_mask << 8) |
479 intel_arch_events[event].eventsel;
483 static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
485 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
486 struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
487 struct kvm_cpuid_entry2 *entry;
488 union cpuid10_eax eax;
489 union cpuid10_edx edx;
490 u64 perf_capabilities;
494 pmu->nr_arch_gp_counters = 0;
495 pmu->nr_arch_fixed_counters = 0;
496 pmu->counter_bitmask[KVM_PMC_GP] = 0;
497 pmu->counter_bitmask[KVM_PMC_FIXED] = 0;
499 pmu->reserved_bits = 0xffffffff00200000ull;
500 pmu->raw_event_mask = X86_RAW_EVENT_MASK;
501 pmu->global_ctrl_mask = ~0ull;
502 pmu->global_status_mask = ~0ull;
503 pmu->fixed_ctr_ctrl_mask = ~0ull;
504 pmu->pebs_enable_mask = ~0ull;
505 pmu->pebs_data_cfg_mask = ~0ull;
507 memset(&lbr_desc->records, 0, sizeof(lbr_desc->records));
510 * Setting passthrough of LBR MSRs is done only in the VM-Entry loop,
511 * and PMU refresh is disallowed after the vCPU has run, i.e. this code
512 * should never be reached while KVM is passing through MSRs.
514 if (KVM_BUG_ON(lbr_desc->msr_passthrough, vcpu->kvm))
517 entry = kvm_find_cpuid_entry(vcpu, 0xa);
518 if (!entry || !vcpu->kvm->arch.enable_pmu)
520 eax.full = entry->eax;
521 edx.full = entry->edx;
523 pmu->version = eax.split.version_id;
527 pmu->nr_arch_gp_counters = min_t(int, eax.split.num_counters,
528 kvm_pmu_cap.num_counters_gp);
529 eax.split.bit_width = min_t(int, eax.split.bit_width,
530 kvm_pmu_cap.bit_width_gp);
531 pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << eax.split.bit_width) - 1;
532 eax.split.mask_length = min_t(int, eax.split.mask_length,
533 kvm_pmu_cap.events_mask_len);
534 pmu->available_event_types = ~entry->ebx &
535 ((1ull << eax.split.mask_length) - 1);
537 if (pmu->version == 1) {
538 pmu->nr_arch_fixed_counters = 0;
540 pmu->nr_arch_fixed_counters = min_t(int, edx.split.num_counters_fixed,
541 kvm_pmu_cap.num_counters_fixed);
542 edx.split.bit_width_fixed = min_t(int, edx.split.bit_width_fixed,
543 kvm_pmu_cap.bit_width_fixed);
544 pmu->counter_bitmask[KVM_PMC_FIXED] =
545 ((u64)1 << edx.split.bit_width_fixed) - 1;
546 setup_fixed_pmc_eventsel(pmu);
549 for (i = 0; i < pmu->nr_arch_fixed_counters; i++)
550 pmu->fixed_ctr_ctrl_mask &= ~(0xbull << (i * 4));
551 counter_mask = ~(((1ull << pmu->nr_arch_gp_counters) - 1) |
552 (((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED));
553 pmu->global_ctrl_mask = counter_mask;
556 * GLOBAL_STATUS and GLOBAL_OVF_CONTROL (a.k.a. GLOBAL_STATUS_RESET)
557 * share reserved bit definitions. The kernel just happens to use
558 * OVF_CTRL for the names.
560 pmu->global_status_mask = pmu->global_ctrl_mask
561 & ~(MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF |
562 MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD);
563 if (vmx_pt_mode_is_host_guest())
564 pmu->global_status_mask &=
565 ~MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI;
567 entry = kvm_find_cpuid_entry_index(vcpu, 7, 0);
569 (boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM)) &&
570 (entry->ebx & (X86_FEATURE_HLE|X86_FEATURE_RTM))) {
571 pmu->reserved_bits ^= HSW_IN_TX;
572 pmu->raw_event_mask |= (HSW_IN_TX|HSW_IN_TX_CHECKPOINTED);
575 bitmap_set(pmu->all_valid_pmc_idx,
576 0, pmu->nr_arch_gp_counters);
577 bitmap_set(pmu->all_valid_pmc_idx,
578 INTEL_PMC_MAX_GENERIC, pmu->nr_arch_fixed_counters);
580 perf_capabilities = vcpu_get_perf_capabilities(vcpu);
581 if (cpuid_model_is_consistent(vcpu) &&
582 (perf_capabilities & PMU_CAP_LBR_FMT))
583 x86_perf_get_lbr(&lbr_desc->records);
585 lbr_desc->records.nr = 0;
587 if (lbr_desc->records.nr)
588 bitmap_set(pmu->all_valid_pmc_idx, INTEL_PMC_IDX_FIXED_VLBR, 1);
590 if (perf_capabilities & PERF_CAP_PEBS_FORMAT) {
591 if (perf_capabilities & PERF_CAP_PEBS_BASELINE) {
592 pmu->pebs_enable_mask = counter_mask;
593 pmu->reserved_bits &= ~ICL_EVENTSEL_ADAPTIVE;
594 for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
595 pmu->fixed_ctr_ctrl_mask &=
596 ~(1ULL << (INTEL_PMC_IDX_FIXED + i * 4));
598 pmu->pebs_data_cfg_mask = ~0xff00000full;
600 pmu->pebs_enable_mask =
601 ~((1ull << pmu->nr_arch_gp_counters) - 1);
606 static void intel_pmu_init(struct kvm_vcpu *vcpu)
609 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
610 struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
612 for (i = 0; i < KVM_INTEL_PMC_MAX_GENERIC; i++) {
613 pmu->gp_counters[i].type = KVM_PMC_GP;
614 pmu->gp_counters[i].vcpu = vcpu;
615 pmu->gp_counters[i].idx = i;
616 pmu->gp_counters[i].current_config = 0;
619 for (i = 0; i < KVM_PMC_MAX_FIXED; i++) {
620 pmu->fixed_counters[i].type = KVM_PMC_FIXED;
621 pmu->fixed_counters[i].vcpu = vcpu;
622 pmu->fixed_counters[i].idx = i + INTEL_PMC_IDX_FIXED;
623 pmu->fixed_counters[i].current_config = 0;
626 lbr_desc->records.nr = 0;
627 lbr_desc->event = NULL;
628 lbr_desc->msr_passthrough = false;
631 static void intel_pmu_reset(struct kvm_vcpu *vcpu)
633 intel_pmu_release_guest_lbr_event(vcpu);
637 * Emulate LBR_On_PMI behavior for 1 < pmu.version < 4.
639 * If Freeze_LBR_On_PMI = 1, the LBR is frozen on PMI and
640 * the KVM emulates to clear the LBR bit (bit 0) in IA32_DEBUGCTL.
642 * Guest needs to re-enable LBR to resume branches recording.
644 static void intel_pmu_legacy_freezing_lbrs_on_pmi(struct kvm_vcpu *vcpu)
646 u64 data = vmcs_read64(GUEST_IA32_DEBUGCTL);
648 if (data & DEBUGCTLMSR_FREEZE_LBRS_ON_PMI) {
649 data &= ~DEBUGCTLMSR_LBR;
650 vmcs_write64(GUEST_IA32_DEBUGCTL, data);
654 static void intel_pmu_deliver_pmi(struct kvm_vcpu *vcpu)
656 u8 version = vcpu_to_pmu(vcpu)->version;
658 if (!intel_pmu_lbr_is_enabled(vcpu))
661 if (version > 1 && version < 4)
662 intel_pmu_legacy_freezing_lbrs_on_pmi(vcpu);
665 static void vmx_update_intercept_for_lbr_msrs(struct kvm_vcpu *vcpu, bool set)
667 struct x86_pmu_lbr *lbr = vcpu_to_lbr_records(vcpu);
670 for (i = 0; i < lbr->nr; i++) {
671 vmx_set_intercept_for_msr(vcpu, lbr->from + i, MSR_TYPE_RW, set);
672 vmx_set_intercept_for_msr(vcpu, lbr->to + i, MSR_TYPE_RW, set);
674 vmx_set_intercept_for_msr(vcpu, lbr->info + i, MSR_TYPE_RW, set);
677 vmx_set_intercept_for_msr(vcpu, MSR_LBR_SELECT, MSR_TYPE_RW, set);
678 vmx_set_intercept_for_msr(vcpu, MSR_LBR_TOS, MSR_TYPE_RW, set);
681 static inline void vmx_disable_lbr_msrs_passthrough(struct kvm_vcpu *vcpu)
683 struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
685 if (!lbr_desc->msr_passthrough)
688 vmx_update_intercept_for_lbr_msrs(vcpu, true);
689 lbr_desc->msr_passthrough = false;
692 static inline void vmx_enable_lbr_msrs_passthrough(struct kvm_vcpu *vcpu)
694 struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
696 if (lbr_desc->msr_passthrough)
699 vmx_update_intercept_for_lbr_msrs(vcpu, false);
700 lbr_desc->msr_passthrough = true;
704 * Higher priority host perf events (e.g. cpu pinned) could reclaim the
705 * pmu resources (e.g. LBR) that were assigned to the guest. This is
706 * usually done via ipi calls (more details in perf_install_in_context).
708 * Before entering the non-root mode (with irq disabled here), double
709 * confirm that the pmu features enabled to the guest are not reclaimed
710 * by higher priority host events. Otherwise, disallow vcpu's access to
711 * the reclaimed features.
713 void vmx_passthrough_lbr_msrs(struct kvm_vcpu *vcpu)
715 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
716 struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
718 if (!lbr_desc->event) {
719 vmx_disable_lbr_msrs_passthrough(vcpu);
720 if (vmcs_read64(GUEST_IA32_DEBUGCTL) & DEBUGCTLMSR_LBR)
722 if (test_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use))
727 if (lbr_desc->event->state < PERF_EVENT_STATE_ACTIVE) {
728 vmx_disable_lbr_msrs_passthrough(vcpu);
729 __clear_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
732 vmx_enable_lbr_msrs_passthrough(vcpu);
737 pr_warn_ratelimited("vcpu-%d: fail to passthrough LBR.\n", vcpu->vcpu_id);
740 static void intel_pmu_cleanup(struct kvm_vcpu *vcpu)
742 if (!(vmcs_read64(GUEST_IA32_DEBUGCTL) & DEBUGCTLMSR_LBR))
743 intel_pmu_release_guest_lbr_event(vcpu);
746 void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu)
748 struct kvm_pmc *pmc = NULL;
751 for_each_set_bit(bit, (unsigned long *)&pmu->global_ctrl,
753 pmc = intel_pmc_idx_to_pmc(pmu, bit);
755 if (!pmc || !pmc_speculative_in_use(pmc) ||
756 !pmc_is_globally_enabled(pmc) || !pmc->perf_event)
760 * A negative index indicates the event isn't mapped to a
761 * physical counter in the host, e.g. due to contention.
763 hw_idx = pmc->perf_event->hw.idx;
764 if (hw_idx != pmc->idx && hw_idx > -1)
765 pmu->host_cross_mapped_mask |= BIT_ULL(hw_idx);
769 struct kvm_pmu_ops intel_pmu_ops __initdata = {
770 .hw_event_available = intel_hw_event_available,
771 .pmc_idx_to_pmc = intel_pmc_idx_to_pmc,
772 .rdpmc_ecx_to_pmc = intel_rdpmc_ecx_to_pmc,
773 .msr_idx_to_pmc = intel_msr_idx_to_pmc,
774 .is_valid_rdpmc_ecx = intel_is_valid_rdpmc_ecx,
775 .is_valid_msr = intel_is_valid_msr,
776 .get_msr = intel_pmu_get_msr,
777 .set_msr = intel_pmu_set_msr,
778 .refresh = intel_pmu_refresh,
779 .init = intel_pmu_init,
780 .reset = intel_pmu_reset,
781 .deliver_pmi = intel_pmu_deliver_pmi,
782 .cleanup = intel_pmu_cleanup,
783 .EVENTSEL_EVENT = ARCH_PERFMON_EVENTSEL_EVENT,
784 .MAX_NR_GP_COUNTERS = KVM_INTEL_PMC_MAX_GENERIC,
785 .MIN_NR_GP_COUNTERS = 1,