arch/x86/kvm/vmx/pmu_intel.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * KVM PMU support for Intel CPUs
   4  *
   5  * Copyright 2011 Red Hat, Inc. and/or its affiliates.
   6  *
   7  * Authors:
   8  *   Avi Kivity   <avi@redhat.com>
   9  *   Gleb Natapov <gleb@redhat.com>
  10  */
  11 #include <linux/types.h>
  12 #include <linux/kvm_host.h>
  13 #include <linux/perf_event.h>
  14 #include <asm/perf_event.h>
  15 #include "x86.h"
  16 #include "cpuid.h"
  17 #include "lapic.h"
  18 #include "nested.h"
  19 #include "pmu.h"
  20
  21 #define MSR_PMC_FULL_WIDTH_BIT      (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0)
  22
  23 static struct kvm_event_hw_type_mapping intel_arch_events[] = {
  24         [0] = { 0x3c, 0x00, PERF_COUNT_HW_CPU_CYCLES },
  25         [1] = { 0xc0, 0x00, PERF_COUNT_HW_INSTRUCTIONS },
  26         [2] = { 0x3c, 0x01, PERF_COUNT_HW_BUS_CYCLES  },
  27         [3] = { 0x2e, 0x4f, PERF_COUNT_HW_CACHE_REFERENCES },
  28         [4] = { 0x2e, 0x41, PERF_COUNT_HW_CACHE_MISSES },
  29         [5] = { 0xc4, 0x00, PERF_COUNT_HW_BRANCH_INSTRUCTIONS },
  30         [6] = { 0xc5, 0x00, PERF_COUNT_HW_BRANCH_MISSES },
  31         /* The above index must match CPUID 0x0A.EBX bit vector */
  32         [7] = { 0x00, 0x03, PERF_COUNT_HW_REF_CPU_CYCLES },
  33 };
  34
  35 /* mapping between fixed pmc index and intel_arch_events array */
  36 static int fixed_pmc_events[] = {1, 0, 7};
  37
  38 static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
  39 {
  40         int i;
  41
  42         for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
  43                 u8 new_ctrl = fixed_ctrl_field(data, i);
  44                 u8 old_ctrl = fixed_ctrl_field(pmu->fixed_ctr_ctrl, i);
  45                 struct kvm_pmc *pmc;
  46
  47                 pmc = get_fixed_pmc(pmu, MSR_CORE_PERF_FIXED_CTR0 + i);
  48
  49                 if (old_ctrl == new_ctrl)
  50                         continue;
  51
  52                 __set_bit(INTEL_PMC_IDX_FIXED + i, pmu->pmc_in_use);
  53                 reprogram_fixed_counter(pmc, new_ctrl, i);
  54         }
  55
  56         pmu->fixed_ctr_ctrl = data;
  57 }
  58
  59 /* function is called when global control register has been updated. */
  60 static void global_ctrl_changed(struct kvm_pmu *pmu, u64 data)
  61 {
  62         int bit;
  63         u64 diff = pmu->global_ctrl ^ data;
  64
  65         pmu->global_ctrl = data;
  66
  67         for_each_set_bit(bit, (unsigned long *)&diff, X86_PMC_IDX_MAX)
  68                 reprogram_counter(pmu, bit);
  69 }
  70
  71 static unsigned int intel_pmc_perf_hw_id(struct kvm_pmc *pmc)
  72 {
  73         struct kvm_pmu *pmu = pmc_to_pmu(pmc);
  74         u8 event_select = pmc->eventsel & ARCH_PERFMON_EVENTSEL_EVENT;
  75         u8 unit_mask = (pmc->eventsel & ARCH_PERFMON_EVENTSEL_UMASK) >> 8;
  76         int i;
  77
  78         for (i = 0; i < ARRAY_SIZE(intel_arch_events); i++) {
  79                 if (intel_arch_events[i].eventsel != event_select ||
  80                     intel_arch_events[i].unit_mask != unit_mask)
  81                         continue;
  82
  83                 /* disable event that reported as not present by cpuid */
  84                 if ((i < 7) && !(pmu->available_event_types & (1 << i)))
  85                         return PERF_COUNT_HW_MAX + 1;
  86
  87                 break;
  88         }
  89
  90         if (i == ARRAY_SIZE(intel_arch_events))
  91                 return PERF_COUNT_HW_MAX;
  92
  93         return intel_arch_events[i].event_type;
  94 }
  95
  96 /* check if a PMC is enabled by comparing it with globl_ctrl bits. */
  97 static bool intel_pmc_is_enabled(struct kvm_pmc *pmc)
  98 {
  99         struct kvm_pmu *pmu = pmc_to_pmu(pmc);
 100
 101         return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl);
 102 }
 103
 104 static struct kvm_pmc *intel_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx)
 105 {
 106         if (pmc_idx < INTEL_PMC_IDX_FIXED)
 107                 return get_gp_pmc(pmu, MSR_P6_EVNTSEL0 + pmc_idx,
 108                                   MSR_P6_EVNTSEL0);
 109         else {
 110                 u32 idx = pmc_idx - INTEL_PMC_IDX_FIXED;
 111
 112                 return get_fixed_pmc(pmu, idx + MSR_CORE_PERF_FIXED_CTR0);
 113         }
 114 }
 115
 116 static bool intel_is_valid_rdpmc_ecx(struct kvm_vcpu *vcpu, unsigned int idx)
 117 {
 118         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 119         bool fixed = idx & (1u << 30);
 120
 121         idx &= ~(3u << 30);
 122
 123         return fixed ? idx < pmu->nr_arch_fixed_counters
 124                      : idx < pmu->nr_arch_gp_counters;
 125 }
 126
 127 static struct kvm_pmc *intel_rdpmc_ecx_to_pmc(struct kvm_vcpu *vcpu,
 128                                             unsigned int idx, u64 *mask)
 129 {
 130         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 131         bool fixed = idx & (1u << 30);
 132         struct kvm_pmc *counters;
 133         unsigned int num_counters;
 134
 135         idx &= ~(3u << 30);
 136         if (fixed) {
 137                 counters = pmu->fixed_counters;
 138                 num_counters = pmu->nr_arch_fixed_counters;
 139         } else {
 140                 counters = pmu->gp_counters;
 141                 num_counters = pmu->nr_arch_gp_counters;
 142         }
 143         if (idx >= num_counters)
 144                 return NULL;
 145         *mask &= pmu->counter_bitmask[fixed ? KVM_PMC_FIXED : KVM_PMC_GP];
 146         return &counters[array_index_nospec(idx, num_counters)];
 147 }
 148
 149 static inline u64 vcpu_get_perf_capabilities(struct kvm_vcpu *vcpu)
 150 {
 151         if (!guest_cpuid_has(vcpu, X86_FEATURE_PDCM))
 152                 return 0;
 153
 154         return vcpu->arch.perf_capabilities;
 155 }
 156
 157 static inline bool fw_writes_is_enabled(struct kvm_vcpu *vcpu)
 158 {
 159         return (vcpu_get_perf_capabilities(vcpu) & PMU_CAP_FW_WRITES) != 0;
 160 }
 161
 162 static inline struct kvm_pmc *get_fw_gp_pmc(struct kvm_pmu *pmu, u32 msr)
 163 {
 164         if (!fw_writes_is_enabled(pmu_to_vcpu(pmu)))
 165                 return NULL;
 166
 167         return get_gp_pmc(pmu, msr, MSR_IA32_PMC0);
 168 }
 169
 170 bool intel_pmu_lbr_is_compatible(struct kvm_vcpu *vcpu)
 171 {
 172         /*
 173          * As a first step, a guest could only enable LBR feature if its
 174          * cpu model is the same as the host because the LBR registers
 175          * would be pass-through to the guest and they're model specific.
 176          */
 177         return boot_cpu_data.x86_model == guest_cpuid_model(vcpu);
 178 }
 179
 180 bool intel_pmu_lbr_is_enabled(struct kvm_vcpu *vcpu)
 181 {
 182         struct x86_pmu_lbr *lbr = vcpu_to_lbr_records(vcpu);
 183
 184         return lbr->nr && (vcpu_get_perf_capabilities(vcpu) & PMU_CAP_LBR_FMT);
 185 }
 186
 187 static bool intel_pmu_is_valid_lbr_msr(struct kvm_vcpu *vcpu, u32 index)
 188 {
 189         struct x86_pmu_lbr *records = vcpu_to_lbr_records(vcpu);
 190         bool ret = false;
 191
 192         if (!intel_pmu_lbr_is_enabled(vcpu))
 193                 return ret;
 194
 195         ret = (index == MSR_LBR_SELECT) || (index == MSR_LBR_TOS) ||
 196                 (index >= records->from && index < records->from + records->nr) ||
 197                 (index >= records->to && index < records->to + records->nr);
 198
 199         if (!ret && records->info)
 200                 ret = (index >= records->info && index < records->info + records->nr);
 201
 202         return ret;
 203 }
 204
 205 static bool intel_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr)
 206 {
 207         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 208         int ret;
 209
 210         switch (msr) {
 211         case MSR_CORE_PERF_FIXED_CTR_CTRL:
 212         case MSR_CORE_PERF_GLOBAL_STATUS:
 213         case MSR_CORE_PERF_GLOBAL_CTRL:
 214         case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
 215                 ret = pmu->version > 1;
 216                 break;
 217         default:
 218                 ret = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0) ||
 219                         get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0) ||
 220                         get_fixed_pmc(pmu, msr) || get_fw_gp_pmc(pmu, msr) ||
 221                         intel_pmu_is_valid_lbr_msr(vcpu, msr);
 222                 break;
 223         }
 224
 225         return ret;
 226 }
 227
 228 static struct kvm_pmc *intel_msr_idx_to_pmc(struct kvm_vcpu *vcpu, u32 msr)
 229 {
 230         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 231         struct kvm_pmc *pmc;
 232
 233         pmc = get_fixed_pmc(pmu, msr);
 234         pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0);
 235         pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0);
 236
 237         return pmc;
 238 }
 239
 240 static inline void intel_pmu_release_guest_lbr_event(struct kvm_vcpu *vcpu)
 241 {
 242         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 243
 244         if (lbr_desc->event) {
 245                 perf_event_release_kernel(lbr_desc->event);
 246                 lbr_desc->event = NULL;
 247                 vcpu_to_pmu(vcpu)->event_count--;
 248         }
 249 }
 250
 251 int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu)
 252 {
 253         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 254         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 255         struct perf_event *event;
 256
 257         /*
 258          * The perf_event_attr is constructed in the minimum efficient way:
 259          * - set 'pinned = true' to make it task pinned so that if another
 260          *   cpu pinned event reclaims LBR, the event->oncpu will be set to -1;
 261          * - set '.exclude_host = true' to record guest branches behavior;
 262          *
 263          * - set '.config = INTEL_FIXED_VLBR_EVENT' to indicates host perf
 264          *   schedule the event without a real HW counter but a fake one;
 265          *   check is_guest_lbr_event() and __intel_get_event_constraints();
 266          *
 267          * - set 'sample_type = PERF_SAMPLE_BRANCH_STACK' and
 268          *   'branch_sample_type = PERF_SAMPLE_BRANCH_CALL_STACK |
 269          *   PERF_SAMPLE_BRANCH_USER' to configure it as a LBR callstack
 270          *   event, which helps KVM to save/restore guest LBR records
 271          *   during host context switches and reduces quite a lot overhead,
 272          *   check branch_user_callstack() and intel_pmu_lbr_sched_task();
 273          */
 274         struct perf_event_attr attr = {
 275                 .type = PERF_TYPE_RAW,
 276                 .size = sizeof(attr),
 277                 .config = INTEL_FIXED_VLBR_EVENT,
 278                 .sample_type = PERF_SAMPLE_BRANCH_STACK,
 279                 .pinned = true,
 280                 .exclude_host = true,
 281                 .branch_sample_type = PERF_SAMPLE_BRANCH_CALL_STACK |
 282                                         PERF_SAMPLE_BRANCH_USER,
 283         };
 284
 285         if (unlikely(lbr_desc->event)) {
 286                 __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
 287                 return 0;
 288         }
 289
 290         event = perf_event_create_kernel_counter(&attr, -1,
 291                                                 current, NULL, NULL);
 292         if (IS_ERR(event)) {
 293                 pr_debug_ratelimited("%s: failed %ld\n",
 294                                         __func__, PTR_ERR(event));
 295                 return PTR_ERR(event);
 296         }
 297         lbr_desc->event = event;
 298         pmu->event_count++;
 299         __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
 300         return 0;
 301 }
 302
 303 /*
 304  * It's safe to access LBR msrs from guest when they have not
 305  * been passthrough since the host would help restore or reset
 306  * the LBR msrs records when the guest LBR event is scheduled in.
 307  */
 308 static bool intel_pmu_handle_lbr_msrs_access(struct kvm_vcpu *vcpu,
 309                                      struct msr_data *msr_info, bool read)
 310 {
 311         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 312         u32 index = msr_info->index;
 313
 314         if (!intel_pmu_is_valid_lbr_msr(vcpu, index))
 315                 return false;
 316
 317         if (!lbr_desc->event && intel_pmu_create_guest_lbr_event(vcpu) < 0)
 318                 goto dummy;
 319
 320         /*
 321          * Disable irq to ensure the LBR feature doesn't get reclaimed by the
 322          * host at the time the value is read from the msr, and this avoids the
 323          * host LBR value to be leaked to the guest. If LBR has been reclaimed,
 324          * return 0 on guest reads.
 325          */
 326         local_irq_disable();
 327         if (lbr_desc->event->state == PERF_EVENT_STATE_ACTIVE) {
 328                 if (read)
 329                         rdmsrl(index, msr_info->data);
 330                 else
 331                         wrmsrl(index, msr_info->data);
 332                 __set_bit(INTEL_PMC_IDX_FIXED_VLBR, vcpu_to_pmu(vcpu)->pmc_in_use);
 333                 local_irq_enable();
 334                 return true;
 335         }
 336         clear_bit(INTEL_PMC_IDX_FIXED_VLBR, vcpu_to_pmu(vcpu)->pmc_in_use);
 337         local_irq_enable();
 338
 339 dummy:
 340         if (read)
 341                 msr_info->data = 0;
 342         return true;
 343 }
 344
 345 static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 346 {
 347         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 348         struct kvm_pmc *pmc;
 349         u32 msr = msr_info->index;
 350
 351         switch (msr) {
 352         case MSR_CORE_PERF_FIXED_CTR_CTRL:
 353                 msr_info->data = pmu->fixed_ctr_ctrl;
 354                 return 0;
 355         case MSR_CORE_PERF_GLOBAL_STATUS:
 356                 msr_info->data = pmu->global_status;
 357                 return 0;
 358         case MSR_CORE_PERF_GLOBAL_CTRL:
 359                 msr_info->data = pmu->global_ctrl;
 360                 return 0;
 361         case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
 362                 msr_info->data = 0;
 363                 return 0;
 364         default:
 365                 if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
 366                     (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) {
 367                         u64 val = pmc_read_counter(pmc);
 368                         msr_info->data =
 369                                 val & pmu->counter_bitmask[KVM_PMC_GP];
 370                         return 0;
 371                 } else if ((pmc = get_fixed_pmc(pmu, msr))) {
 372                         u64 val = pmc_read_counter(pmc);
 373                         msr_info->data =
 374                                 val & pmu->counter_bitmask[KVM_PMC_FIXED];
 375                         return 0;
 376                 } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
 377                         msr_info->data = pmc->eventsel;
 378                         return 0;
 379                 } else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, true))
 380                         return 0;
 381         }
 382
 383         return 1;
 384 }
 385
 386 static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 387 {
 388         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 389         struct kvm_pmc *pmc;
 390         u32 msr = msr_info->index;
 391         u64 data = msr_info->data;
 392
 393         switch (msr) {
 394         case MSR_CORE_PERF_FIXED_CTR_CTRL:
 395                 if (pmu->fixed_ctr_ctrl == data)
 396                         return 0;
 397                 if (!(data & 0xfffffffffffff444ull)) {
 398                         reprogram_fixed_counters(pmu, data);
 399                         return 0;
 400                 }
 401                 break;
 402         case MSR_CORE_PERF_GLOBAL_STATUS:
 403                 if (msr_info->host_initiated) {
 404                         pmu->global_status = data;
 405                         return 0;
 406                 }
 407                 break; /* RO MSR */
 408         case MSR_CORE_PERF_GLOBAL_CTRL:
 409                 if (pmu->global_ctrl == data)
 410                         return 0;
 411                 if (kvm_valid_perf_global_ctrl(pmu, data)) {
 412                         global_ctrl_changed(pmu, data);
 413                         return 0;
 414                 }
 415                 break;
 416         case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
 417                 if (!(data & pmu->global_ovf_ctrl_mask)) {
 418                         if (!msr_info->host_initiated)
 419                                 pmu->global_status &= ~data;
 420                         return 0;
 421                 }
 422                 break;
 423         default:
 424                 if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
 425                     (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) {
 426                         if ((msr & MSR_PMC_FULL_WIDTH_BIT) &&
 427                             (data & ~pmu->counter_bitmask[KVM_PMC_GP]))
 428                                 return 1;
 429                         if (!msr_info->host_initiated &&
 430                             !(msr & MSR_PMC_FULL_WIDTH_BIT))
 431                                 data = (s64)(s32)data;
 432                         pmc->counter += data - pmc_read_counter(pmc);
 433                         if (pmc->perf_event && !pmc->is_paused)
 434                                 perf_event_period(pmc->perf_event,
 435                                                   get_sample_period(pmc, data));
 436                         return 0;
 437                 } else if ((pmc = get_fixed_pmc(pmu, msr))) {
 438                         pmc->counter += data - pmc_read_counter(pmc);
 439                         if (pmc->perf_event && !pmc->is_paused)
 440                                 perf_event_period(pmc->perf_event,
 441                                                   get_sample_period(pmc, data));
 442                         return 0;
 443                 } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
 444                         if (data == pmc->eventsel)
 445                                 return 0;
 446                         if (!(data & pmu->reserved_bits)) {
 447                                 reprogram_gp_counter(pmc, data);
 448                                 return 0;
 449                         }
 450                 } else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, false))
 451                         return 0;
 452         }
 453
 454         return 1;
 455 }
 456
 457 static void setup_fixed_pmc_eventsel(struct kvm_pmu *pmu)
 458 {
 459         size_t size = ARRAY_SIZE(fixed_pmc_events);
 460         struct kvm_pmc *pmc;
 461         u32 event;
 462         int i;
 463
 464         for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
 465                 pmc = &pmu->fixed_counters[i];
 466                 event = fixed_pmc_events[array_index_nospec(i, size)];
 467                 pmc->eventsel = (intel_arch_events[event].unit_mask << 8) |
 468                         intel_arch_events[event].eventsel;
 469         }
 470 }
 471
 472 static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
 473 {
 474         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 475         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 476
 477         struct x86_pmu_capability x86_pmu;
 478         struct kvm_cpuid_entry2 *entry;
 479         union cpuid10_eax eax;
 480         union cpuid10_edx edx;
 481
 482         pmu->nr_arch_gp_counters = 0;
 483         pmu->nr_arch_fixed_counters = 0;
 484         pmu->counter_bitmask[KVM_PMC_GP] = 0;
 485         pmu->counter_bitmask[KVM_PMC_FIXED] = 0;
 486         pmu->version = 0;
 487         pmu->reserved_bits = 0xffffffff00200000ull;
 488
 489         entry = kvm_find_cpuid_entry(vcpu, 0xa, 0);
 490         if (!entry || !enable_pmu)
 491                 return;
 492         eax.full = entry->eax;
 493         edx.full = entry->edx;
 494
 495         pmu->version = eax.split.version_id;
 496         if (!pmu->version)
 497                 return;
 498
 499         perf_get_x86_pmu_capability(&x86_pmu);
 500
 501         pmu->nr_arch_gp_counters = min_t(int, eax.split.num_counters,
 502                                          x86_pmu.num_counters_gp);
 503         eax.split.bit_width = min_t(int, eax.split.bit_width, x86_pmu.bit_width_gp);
 504         pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << eax.split.bit_width) - 1;
 505         eax.split.mask_length = min_t(int, eax.split.mask_length, x86_pmu.events_mask_len);
 506         pmu->available_event_types = ~entry->ebx &
 507                                         ((1ull << eax.split.mask_length) - 1);
 508
 509         if (pmu->version == 1) {
 510                 pmu->nr_arch_fixed_counters = 0;
 511         } else {
 512                 pmu->nr_arch_fixed_counters =
 513                         min3(ARRAY_SIZE(fixed_pmc_events),
 514                              (size_t) edx.split.num_counters_fixed,
 515                              (size_t) x86_pmu.num_counters_fixed);
 516                 edx.split.bit_width_fixed = min_t(int,
 517                         edx.split.bit_width_fixed, x86_pmu.bit_width_fixed);
 518                 pmu->counter_bitmask[KVM_PMC_FIXED] =
 519                         ((u64)1 << edx.split.bit_width_fixed) - 1;
 520                 setup_fixed_pmc_eventsel(pmu);
 521         }
 522
 523         pmu->global_ctrl = ((1ull << pmu->nr_arch_gp_counters) - 1) |
 524                 (((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED);
 525         pmu->global_ctrl_mask = ~pmu->global_ctrl;
 526         pmu->global_ovf_ctrl_mask = pmu->global_ctrl_mask
 527                         & ~(MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF |
 528                             MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD);
 529         if (vmx_pt_mode_is_host_guest())
 530                 pmu->global_ovf_ctrl_mask &=
 531                                 ~MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI;
 532
 533         entry = kvm_find_cpuid_entry(vcpu, 7, 0);
 534         if (entry &&
 535             (boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM)) &&
 536             (entry->ebx & (X86_FEATURE_HLE|X86_FEATURE_RTM)))
 537                 pmu->reserved_bits ^= HSW_IN_TX|HSW_IN_TX_CHECKPOINTED;
 538
 539         bitmap_set(pmu->all_valid_pmc_idx,
 540                 0, pmu->nr_arch_gp_counters);
 541         bitmap_set(pmu->all_valid_pmc_idx,
 542                 INTEL_PMC_MAX_GENERIC, pmu->nr_arch_fixed_counters);
 543
 544         nested_vmx_pmu_entry_exit_ctls_update(vcpu);
 545
 546         if (intel_pmu_lbr_is_compatible(vcpu))
 547                 x86_perf_get_lbr(&lbr_desc->records);
 548         else
 549                 lbr_desc->records.nr = 0;
 550
 551         if (lbr_desc->records.nr)
 552                 bitmap_set(pmu->all_valid_pmc_idx, INTEL_PMC_IDX_FIXED_VLBR, 1);
 553 }
 554
 555 static void intel_pmu_init(struct kvm_vcpu *vcpu)
 556 {
 557         int i;
 558         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 559         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 560
 561         for (i = 0; i < INTEL_PMC_MAX_GENERIC; i++) {
 562                 pmu->gp_counters[i].type = KVM_PMC_GP;
 563                 pmu->gp_counters[i].vcpu = vcpu;
 564                 pmu->gp_counters[i].idx = i;
 565                 pmu->gp_counters[i].current_config = 0;
 566         }
 567
 568         for (i = 0; i < INTEL_PMC_MAX_FIXED; i++) {
 569                 pmu->fixed_counters[i].type = KVM_PMC_FIXED;
 570                 pmu->fixed_counters[i].vcpu = vcpu;
 571                 pmu->fixed_counters[i].idx = i + INTEL_PMC_IDX_FIXED;
 572                 pmu->fixed_counters[i].current_config = 0;
 573         }
 574
 575         vcpu->arch.perf_capabilities = vmx_get_perf_capabilities();
 576         lbr_desc->records.nr = 0;
 577         lbr_desc->event = NULL;
 578         lbr_desc->msr_passthrough = false;
 579 }
 580
 581 static void intel_pmu_reset(struct kvm_vcpu *vcpu)
 582 {
 583         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 584         struct kvm_pmc *pmc = NULL;
 585         int i;
 586
 587         for (i = 0; i < INTEL_PMC_MAX_GENERIC; i++) {
 588                 pmc = &pmu->gp_counters[i];
 589
 590                 pmc_stop_counter(pmc);
 591                 pmc->counter = pmc->eventsel = 0;
 592         }
 593
 594         for (i = 0; i < INTEL_PMC_MAX_FIXED; i++) {
 595                 pmc = &pmu->fixed_counters[i];
 596
 597                 pmc_stop_counter(pmc);
 598                 pmc->counter = 0;
 599         }
 600
 601         pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status = 0;
 602
 603         intel_pmu_release_guest_lbr_event(vcpu);
 604 }
 605
 606 /*
 607  * Emulate LBR_On_PMI behavior for 1 < pmu.version < 4.
 608  *
 609  * If Freeze_LBR_On_PMI = 1, the LBR is frozen on PMI and
 610  * the KVM emulates to clear the LBR bit (bit 0) in IA32_DEBUGCTL.
 611  *
 612  * Guest needs to re-enable LBR to resume branches recording.
 613  */
 614 static void intel_pmu_legacy_freezing_lbrs_on_pmi(struct kvm_vcpu *vcpu)
 615 {
 616         u64 data = vmcs_read64(GUEST_IA32_DEBUGCTL);
 617
 618         if (data & DEBUGCTLMSR_FREEZE_LBRS_ON_PMI) {
 619                 data &= ~DEBUGCTLMSR_LBR;
 620                 vmcs_write64(GUEST_IA32_DEBUGCTL, data);
 621         }
 622 }
 623
 624 static void intel_pmu_deliver_pmi(struct kvm_vcpu *vcpu)
 625 {
 626         u8 version = vcpu_to_pmu(vcpu)->version;
 627
 628         if (!intel_pmu_lbr_is_enabled(vcpu))
 629                 return;
 630
 631         if (version > 1 && version < 4)
 632                 intel_pmu_legacy_freezing_lbrs_on_pmi(vcpu);
 633 }
 634
 635 static void vmx_update_intercept_for_lbr_msrs(struct kvm_vcpu *vcpu, bool set)
 636 {
 637         struct x86_pmu_lbr *lbr = vcpu_to_lbr_records(vcpu);
 638         int i;
 639
 640         for (i = 0; i < lbr->nr; i++) {
 641                 vmx_set_intercept_for_msr(vcpu, lbr->from + i, MSR_TYPE_RW, set);
 642                 vmx_set_intercept_for_msr(vcpu, lbr->to + i, MSR_TYPE_RW, set);
 643                 if (lbr->info)
 644                         vmx_set_intercept_for_msr(vcpu, lbr->info + i, MSR_TYPE_RW, set);
 645         }
 646
 647         vmx_set_intercept_for_msr(vcpu, MSR_LBR_SELECT, MSR_TYPE_RW, set);
 648         vmx_set_intercept_for_msr(vcpu, MSR_LBR_TOS, MSR_TYPE_RW, set);
 649 }
 650
 651 static inline void vmx_disable_lbr_msrs_passthrough(struct kvm_vcpu *vcpu)
 652 {
 653         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 654
 655         if (!lbr_desc->msr_passthrough)
 656                 return;
 657
 658         vmx_update_intercept_for_lbr_msrs(vcpu, true);
 659         lbr_desc->msr_passthrough = false;
 660 }
 661
 662 static inline void vmx_enable_lbr_msrs_passthrough(struct kvm_vcpu *vcpu)
 663 {
 664         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 665
 666         if (lbr_desc->msr_passthrough)
 667                 return;
 668
 669         vmx_update_intercept_for_lbr_msrs(vcpu, false);
 670         lbr_desc->msr_passthrough = true;
 671 }
 672
 673 /*
 674  * Higher priority host perf events (e.g. cpu pinned) could reclaim the
 675  * pmu resources (e.g. LBR) that were assigned to the guest. This is
 676  * usually done via ipi calls (more details in perf_install_in_context).
 677  *
 678  * Before entering the non-root mode (with irq disabled here), double
 679  * confirm that the pmu features enabled to the guest are not reclaimed
 680  * by higher priority host events. Otherwise, disallow vcpu's access to
 681  * the reclaimed features.
 682  */
 683 void vmx_passthrough_lbr_msrs(struct kvm_vcpu *vcpu)
 684 {
 685         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 686         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
 687
 688         if (!lbr_desc->event) {
 689                 vmx_disable_lbr_msrs_passthrough(vcpu);
 690                 if (vmcs_read64(GUEST_IA32_DEBUGCTL) & DEBUGCTLMSR_LBR)
 691                         goto warn;
 692                 if (test_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use))
 693                         goto warn;
 694                 return;
 695         }
 696
 697         if (lbr_desc->event->state < PERF_EVENT_STATE_ACTIVE) {
 698                 vmx_disable_lbr_msrs_passthrough(vcpu);
 699                 __clear_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
 700                 goto warn;
 701         } else
 702                 vmx_enable_lbr_msrs_passthrough(vcpu);
 703
 704         return;
 705
 706 warn:
 707         pr_warn_ratelimited("kvm: vcpu-%d: fail to passthrough LBR.\n",
 708                 vcpu->vcpu_id);
 709 }
 710
 711 static void intel_pmu_cleanup(struct kvm_vcpu *vcpu)
 712 {
 713         if (!(vmcs_read64(GUEST_IA32_DEBUGCTL) & DEBUGCTLMSR_LBR))
 714                 intel_pmu_release_guest_lbr_event(vcpu);
 715 }
 716
 717 struct kvm_pmu_ops intel_pmu_ops = {
 718         .pmc_perf_hw_id = intel_pmc_perf_hw_id,
 719         .pmc_is_enabled = intel_pmc_is_enabled,
 720         .pmc_idx_to_pmc = intel_pmc_idx_to_pmc,
 721         .rdpmc_ecx_to_pmc = intel_rdpmc_ecx_to_pmc,
 722         .msr_idx_to_pmc = intel_msr_idx_to_pmc,
 723         .is_valid_rdpmc_ecx = intel_is_valid_rdpmc_ecx,
 724         .is_valid_msr = intel_is_valid_msr,
 725         .get_msr = intel_pmu_get_msr,
 726         .set_msr = intel_pmu_set_msr,
 727         .refresh = intel_pmu_refresh,
 728         .init = intel_pmu_init,
 729         .reset = intel_pmu_reset,
 730         .deliver_pmi = intel_pmu_deliver_pmi,
 731         .cleanup = intel_pmu_cleanup,
 732 };