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