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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 | // SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2023, Tencent, Inc. */ #define _GNU_SOURCE /* for program_invocation_short_name */ #include <x86intrin.h> #include "pmu.h" #include "processor.h" /* Number of LOOP instructions for the guest measurement payload. */ #define NUM_BRANCHES 10 /* * Number of "extra" instructions that will be counted, i.e. the number of * instructions that are needed to set up the loop and then disabled the * counter. 1 CLFLUSH/CLFLUSHOPT/NOP, 1 MFENCE, 2 MOV, 2 XOR, 1 WRMSR. */ #define NUM_EXTRA_INSNS 7 #define NUM_INSNS_RETIRED (NUM_BRANCHES + NUM_EXTRA_INSNS) static uint8_t kvm_pmu_version; static bool kvm_has_perf_caps; static bool is_forced_emulation_enabled; static struct kvm_vm *pmu_vm_create_with_one_vcpu(struct kvm_vcpu **vcpu, void *guest_code, uint8_t pmu_version, uint64_t perf_capabilities) { struct kvm_vm *vm; vm = vm_create_with_one_vcpu(vcpu, guest_code); vm_init_descriptor_tables(vm); vcpu_init_descriptor_tables(*vcpu); sync_global_to_guest(vm, kvm_pmu_version); sync_global_to_guest(vm, is_forced_emulation_enabled); /* * Set PERF_CAPABILITIES before PMU version as KVM disallows enabling * features via PERF_CAPABILITIES if the guest doesn't have a vPMU. */ if (kvm_has_perf_caps) vcpu_set_msr(*vcpu, MSR_IA32_PERF_CAPABILITIES, perf_capabilities); vcpu_set_cpuid_property(*vcpu, X86_PROPERTY_PMU_VERSION, pmu_version); return vm; } static void run_vcpu(struct kvm_vcpu *vcpu) { struct ucall uc; do { vcpu_run(vcpu); switch (get_ucall(vcpu, &uc)) { case UCALL_SYNC: break; case UCALL_ABORT: REPORT_GUEST_ASSERT(uc); break; case UCALL_PRINTF: pr_info("%s", uc.buffer); break; case UCALL_DONE: break; default: TEST_FAIL("Unexpected ucall: %lu", uc.cmd); } } while (uc.cmd != UCALL_DONE); } static uint8_t guest_get_pmu_version(void) { /* * Return the effective PMU version, i.e. the minimum between what KVM * supports and what is enumerated to the guest. The host deliberately * advertises a PMU version to the guest beyond what is actually * supported by KVM to verify KVM doesn't freak out and do something * bizarre with an architecturally valid, but unsupported, version. */ return min_t(uint8_t, kvm_pmu_version, this_cpu_property(X86_PROPERTY_PMU_VERSION)); } /* * If an architectural event is supported and guaranteed to generate at least * one "hit, assert that its count is non-zero. If an event isn't supported or * the test can't guarantee the associated action will occur, then all bets are * off regarding the count, i.e. no checks can be done. * * Sanity check that in all cases, the event doesn't count when it's disabled, * and that KVM correctly emulates the write of an arbitrary value. */ static void guest_assert_event_count(uint8_t idx, struct kvm_x86_pmu_feature event, uint32_t pmc, uint32_t pmc_msr) { uint64_t count; count = _rdpmc(pmc); if (!this_pmu_has(event)) goto sanity_checks; switch (idx) { case INTEL_ARCH_INSTRUCTIONS_RETIRED_INDEX: GUEST_ASSERT_EQ(count, NUM_INSNS_RETIRED); break; case INTEL_ARCH_BRANCHES_RETIRED_INDEX: GUEST_ASSERT_EQ(count, NUM_BRANCHES); break; case INTEL_ARCH_LLC_REFERENCES_INDEX: case INTEL_ARCH_LLC_MISSES_INDEX: if (!this_cpu_has(X86_FEATURE_CLFLUSHOPT) && !this_cpu_has(X86_FEATURE_CLFLUSH)) break; fallthrough; case INTEL_ARCH_CPU_CYCLES_INDEX: case INTEL_ARCH_REFERENCE_CYCLES_INDEX: GUEST_ASSERT_NE(count, 0); break; case INTEL_ARCH_TOPDOWN_SLOTS_INDEX: GUEST_ASSERT(count >= NUM_INSNS_RETIRED); break; default: break; } sanity_checks: __asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES})); GUEST_ASSERT_EQ(_rdpmc(pmc), count); wrmsr(pmc_msr, 0xdead); GUEST_ASSERT_EQ(_rdpmc(pmc), 0xdead); } /* * Enable and disable the PMC in a monolithic asm blob to ensure that the * compiler can't insert _any_ code into the measured sequence. Note, ECX * doesn't need to be clobbered as the input value, @pmc_msr, is restored * before the end of the sequence. * * If CLFUSH{,OPT} is supported, flush the cacheline containing (at least) the * start of the loop to force LLC references and misses, i.e. to allow testing * that those events actually count. * * If forced emulation is enabled (and specified), force emulation on a subset * of the measured code to verify that KVM correctly emulates instructions and * branches retired events in conjunction with hardware also counting said * events. */ #define GUEST_MEASURE_EVENT(_msr, _value, clflush, FEP) \ do { \ __asm__ __volatile__("wrmsr\n\t" \ clflush "\n\t" \ "mfence\n\t" \ "1: mov $" __stringify(NUM_BRANCHES) ", %%ecx\n\t" \ FEP "loop .\n\t" \ FEP "mov %%edi, %%ecx\n\t" \ FEP "xor %%eax, %%eax\n\t" \ FEP "xor %%edx, %%edx\n\t" \ "wrmsr\n\t" \ :: "a"((uint32_t)_value), "d"(_value >> 32), \ "c"(_msr), "D"(_msr) \ ); \ } while (0) #define GUEST_TEST_EVENT(_idx, _event, _pmc, _pmc_msr, _ctrl_msr, _value, FEP) \ do { \ wrmsr(pmc_msr, 0); \ \ if (this_cpu_has(X86_FEATURE_CLFLUSHOPT)) \ GUEST_MEASURE_EVENT(_ctrl_msr, _value, "clflushopt 1f", FEP); \ else if (this_cpu_has(X86_FEATURE_CLFLUSH)) \ GUEST_MEASURE_EVENT(_ctrl_msr, _value, "clflush 1f", FEP); \ else \ GUEST_MEASURE_EVENT(_ctrl_msr, _value, "nop", FEP); \ \ guest_assert_event_count(_idx, _event, _pmc, _pmc_msr); \ } while (0) static void __guest_test_arch_event(uint8_t idx, struct kvm_x86_pmu_feature event, uint32_t pmc, uint32_t pmc_msr, uint32_t ctrl_msr, uint64_t ctrl_msr_value) { GUEST_TEST_EVENT(idx, event, pmc, pmc_msr, ctrl_msr, ctrl_msr_value, ""); if (is_forced_emulation_enabled) GUEST_TEST_EVENT(idx, event, pmc, pmc_msr, ctrl_msr, ctrl_msr_value, KVM_FEP); } #define X86_PMU_FEATURE_NULL \ ({ \ struct kvm_x86_pmu_feature feature = {}; \ \ feature; \ }) static bool pmu_is_null_feature(struct kvm_x86_pmu_feature event) { return !(*(u64 *)&event); } static void guest_test_arch_event(uint8_t idx) { const struct { struct kvm_x86_pmu_feature gp_event; struct kvm_x86_pmu_feature fixed_event; } intel_event_to_feature[] = { [INTEL_ARCH_CPU_CYCLES_INDEX] = { X86_PMU_FEATURE_CPU_CYCLES, X86_PMU_FEATURE_CPU_CYCLES_FIXED }, [INTEL_ARCH_INSTRUCTIONS_RETIRED_INDEX] = { X86_PMU_FEATURE_INSNS_RETIRED, X86_PMU_FEATURE_INSNS_RETIRED_FIXED }, /* * Note, the fixed counter for reference cycles is NOT the same * as the general purpose architectural event. The fixed counter * explicitly counts at the same frequency as the TSC, whereas * the GP event counts at a fixed, but uarch specific, frequency. * Bundle them here for simplicity. */ [INTEL_ARCH_REFERENCE_CYCLES_INDEX] = { X86_PMU_FEATURE_REFERENCE_CYCLES, X86_PMU_FEATURE_REFERENCE_TSC_CYCLES_FIXED }, [INTEL_ARCH_LLC_REFERENCES_INDEX] = { X86_PMU_FEATURE_LLC_REFERENCES, X86_PMU_FEATURE_NULL }, [INTEL_ARCH_LLC_MISSES_INDEX] = { X86_PMU_FEATURE_LLC_MISSES, X86_PMU_FEATURE_NULL }, [INTEL_ARCH_BRANCHES_RETIRED_INDEX] = { X86_PMU_FEATURE_BRANCH_INSNS_RETIRED, X86_PMU_FEATURE_NULL }, [INTEL_ARCH_BRANCHES_MISPREDICTED_INDEX] = { X86_PMU_FEATURE_BRANCHES_MISPREDICTED, X86_PMU_FEATURE_NULL }, [INTEL_ARCH_TOPDOWN_SLOTS_INDEX] = { X86_PMU_FEATURE_TOPDOWN_SLOTS, X86_PMU_FEATURE_TOPDOWN_SLOTS_FIXED }, }; uint32_t nr_gp_counters = this_cpu_property(X86_PROPERTY_PMU_NR_GP_COUNTERS); uint32_t pmu_version = guest_get_pmu_version(); /* PERF_GLOBAL_CTRL exists only for Architectural PMU Version 2+. */ bool guest_has_perf_global_ctrl = pmu_version >= 2; struct kvm_x86_pmu_feature gp_event, fixed_event; uint32_t base_pmc_msr; unsigned int i; /* The host side shouldn't invoke this without a guest PMU. */ GUEST_ASSERT(pmu_version); if (this_cpu_has(X86_FEATURE_PDCM) && rdmsr(MSR_IA32_PERF_CAPABILITIES) & PMU_CAP_FW_WRITES) base_pmc_msr = MSR_IA32_PMC0; else base_pmc_msr = MSR_IA32_PERFCTR0; gp_event = intel_event_to_feature[idx].gp_event; GUEST_ASSERT_EQ(idx, gp_event.f.bit); GUEST_ASSERT(nr_gp_counters); for (i = 0; i < nr_gp_counters; i++) { uint64_t eventsel = ARCH_PERFMON_EVENTSEL_OS | ARCH_PERFMON_EVENTSEL_ENABLE | intel_pmu_arch_events[idx]; wrmsr(MSR_P6_EVNTSEL0 + i, 0); if (guest_has_perf_global_ctrl) wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, BIT_ULL(i)); __guest_test_arch_event(idx, gp_event, i, base_pmc_msr + i, MSR_P6_EVNTSEL0 + i, eventsel); } if (!guest_has_perf_global_ctrl) return; fixed_event = intel_event_to_feature[idx].fixed_event; if (pmu_is_null_feature(fixed_event) || !this_pmu_has(fixed_event)) return; i = fixed_event.f.bit; wrmsr(MSR_CORE_PERF_FIXED_CTR_CTRL, FIXED_PMC_CTRL(i, FIXED_PMC_KERNEL)); __guest_test_arch_event(idx, fixed_event, i | INTEL_RDPMC_FIXED, MSR_CORE_PERF_FIXED_CTR0 + i, MSR_CORE_PERF_GLOBAL_CTRL, FIXED_PMC_GLOBAL_CTRL_ENABLE(i)); } static void guest_test_arch_events(void) { uint8_t i; for (i = 0; i < NR_INTEL_ARCH_EVENTS; i++) guest_test_arch_event(i); GUEST_DONE(); } static void test_arch_events(uint8_t pmu_version, uint64_t perf_capabilities, uint8_t length, uint8_t unavailable_mask) { struct kvm_vcpu *vcpu; struct kvm_vm *vm; /* Testing arch events requires a vPMU (there are no negative tests). */ if (!pmu_version) return; vm = pmu_vm_create_with_one_vcpu(&vcpu, guest_test_arch_events, pmu_version, perf_capabilities); vcpu_set_cpuid_property(vcpu, X86_PROPERTY_PMU_EBX_BIT_VECTOR_LENGTH, length); vcpu_set_cpuid_property(vcpu, X86_PROPERTY_PMU_EVENTS_MASK, unavailable_mask); run_vcpu(vcpu); kvm_vm_free(vm); } /* * Limit testing to MSRs that are actually defined by Intel (in the SDM). MSRs * that aren't defined counter MSRs *probably* don't exist, but there's no * guarantee that currently undefined MSR indices won't be used for something * other than PMCs in the future. */ #define MAX_NR_GP_COUNTERS 8 #define MAX_NR_FIXED_COUNTERS 3 #define GUEST_ASSERT_PMC_MSR_ACCESS(insn, msr, expect_gp, vector) \ __GUEST_ASSERT(expect_gp ? vector == GP_VECTOR : !vector, \ "Expected %s on " #insn "(0x%x), got vector %u", \ expect_gp ? "#GP" : "no fault", msr, vector) \ #define GUEST_ASSERT_PMC_VALUE(insn, msr, val, expected) \ __GUEST_ASSERT(val == expected_val, \ "Expected " #insn "(0x%x) to yield 0x%lx, got 0x%lx", \ msr, expected_val, val); static void guest_test_rdpmc(uint32_t rdpmc_idx, bool expect_success, uint64_t expected_val) { uint8_t vector; uint64_t val; vector = rdpmc_safe(rdpmc_idx, &val); GUEST_ASSERT_PMC_MSR_ACCESS(RDPMC, rdpmc_idx, !expect_success, vector); if (expect_success) GUEST_ASSERT_PMC_VALUE(RDPMC, rdpmc_idx, val, expected_val); if (!is_forced_emulation_enabled) return; vector = rdpmc_safe_fep(rdpmc_idx, &val); GUEST_ASSERT_PMC_MSR_ACCESS(RDPMC, rdpmc_idx, !expect_success, vector); if (expect_success) GUEST_ASSERT_PMC_VALUE(RDPMC, rdpmc_idx, val, expected_val); } static void guest_rd_wr_counters(uint32_t base_msr, uint8_t nr_possible_counters, uint8_t nr_counters, uint32_t or_mask) { const bool pmu_has_fast_mode = !guest_get_pmu_version(); uint8_t i; for (i = 0; i < nr_possible_counters; i++) { /* * TODO: Test a value that validates full-width writes and the * width of the counters. */ const uint64_t test_val = 0xffff; const uint32_t msr = base_msr + i; /* * Fixed counters are supported if the counter is less than the * number of enumerated contiguous counters *or* the counter is * explicitly enumerated in the supported counters mask. */ const bool expect_success = i < nr_counters || (or_mask & BIT(i)); /* * KVM drops writes to MSR_P6_PERFCTR[0|1] if the counters are * unsupported, i.e. doesn't #GP and reads back '0'. */ const uint64_t expected_val = expect_success ? test_val : 0; const bool expect_gp = !expect_success && msr != MSR_P6_PERFCTR0 && msr != MSR_P6_PERFCTR1; uint32_t rdpmc_idx; uint8_t vector; uint64_t val; vector = wrmsr_safe(msr, test_val); GUEST_ASSERT_PMC_MSR_ACCESS(WRMSR, msr, expect_gp, vector); vector = rdmsr_safe(msr, &val); GUEST_ASSERT_PMC_MSR_ACCESS(RDMSR, msr, expect_gp, vector); /* On #GP, the result of RDMSR is undefined. */ if (!expect_gp) GUEST_ASSERT_PMC_VALUE(RDMSR, msr, val, expected_val); /* * Redo the read tests with RDPMC, which has different indexing * semantics and additional capabilities. */ rdpmc_idx = i; if (base_msr == MSR_CORE_PERF_FIXED_CTR0) rdpmc_idx |= INTEL_RDPMC_FIXED; guest_test_rdpmc(rdpmc_idx, expect_success, expected_val); /* * KVM doesn't support non-architectural PMUs, i.e. it should * impossible to have fast mode RDPMC. Verify that attempting * to use fast RDPMC always #GPs. */ GUEST_ASSERT(!expect_success || !pmu_has_fast_mode); rdpmc_idx |= INTEL_RDPMC_FAST; guest_test_rdpmc(rdpmc_idx, false, -1ull); vector = wrmsr_safe(msr, 0); GUEST_ASSERT_PMC_MSR_ACCESS(WRMSR, msr, expect_gp, vector); } } static void guest_test_gp_counters(void) { uint8_t pmu_version = guest_get_pmu_version(); uint8_t nr_gp_counters = 0; uint32_t base_msr; if (pmu_version) nr_gp_counters = this_cpu_property(X86_PROPERTY_PMU_NR_GP_COUNTERS); /* * For v2+ PMUs, PERF_GLOBAL_CTRL's architectural post-RESET value is * "Sets bits n-1:0 and clears the upper bits", where 'n' is the number * of GP counters. If there are no GP counters, require KVM to leave * PERF_GLOBAL_CTRL '0'. This edge case isn't covered by the SDM, but * follow the spirit of the architecture and only globally enable GP * counters, of which there are none. */ if (pmu_version > 1) { uint64_t global_ctrl = rdmsr(MSR_CORE_PERF_GLOBAL_CTRL); if (nr_gp_counters) GUEST_ASSERT_EQ(global_ctrl, GENMASK_ULL(nr_gp_counters - 1, 0)); else GUEST_ASSERT_EQ(global_ctrl, 0); } if (this_cpu_has(X86_FEATURE_PDCM) && rdmsr(MSR_IA32_PERF_CAPABILITIES) & PMU_CAP_FW_WRITES) base_msr = MSR_IA32_PMC0; else base_msr = MSR_IA32_PERFCTR0; guest_rd_wr_counters(base_msr, MAX_NR_GP_COUNTERS, nr_gp_counters, 0); GUEST_DONE(); } static void test_gp_counters(uint8_t pmu_version, uint64_t perf_capabilities, uint8_t nr_gp_counters) { struct kvm_vcpu *vcpu; struct kvm_vm *vm; vm = pmu_vm_create_with_one_vcpu(&vcpu, guest_test_gp_counters, pmu_version, perf_capabilities); vcpu_set_cpuid_property(vcpu, X86_PROPERTY_PMU_NR_GP_COUNTERS, nr_gp_counters); run_vcpu(vcpu); kvm_vm_free(vm); } static void guest_test_fixed_counters(void) { uint64_t supported_bitmask = 0; uint8_t nr_fixed_counters = 0; uint8_t i; /* Fixed counters require Architectural vPMU Version 2+. */ if (guest_get_pmu_version() >= 2) nr_fixed_counters = this_cpu_property(X86_PROPERTY_PMU_NR_FIXED_COUNTERS); /* * The supported bitmask for fixed counters was introduced in PMU * version 5. */ if (guest_get_pmu_version() >= 5) supported_bitmask = this_cpu_property(X86_PROPERTY_PMU_FIXED_COUNTERS_BITMASK); guest_rd_wr_counters(MSR_CORE_PERF_FIXED_CTR0, MAX_NR_FIXED_COUNTERS, nr_fixed_counters, supported_bitmask); for (i = 0; i < MAX_NR_FIXED_COUNTERS; i++) { uint8_t vector; uint64_t val; if (i >= nr_fixed_counters && !(supported_bitmask & BIT_ULL(i))) { vector = wrmsr_safe(MSR_CORE_PERF_FIXED_CTR_CTRL, FIXED_PMC_CTRL(i, FIXED_PMC_KERNEL)); __GUEST_ASSERT(vector == GP_VECTOR, "Expected #GP for counter %u in FIXED_CTR_CTRL", i); vector = wrmsr_safe(MSR_CORE_PERF_GLOBAL_CTRL, FIXED_PMC_GLOBAL_CTRL_ENABLE(i)); __GUEST_ASSERT(vector == GP_VECTOR, "Expected #GP for counter %u in PERF_GLOBAL_CTRL", i); continue; } wrmsr(MSR_CORE_PERF_FIXED_CTR0 + i, 0); wrmsr(MSR_CORE_PERF_FIXED_CTR_CTRL, FIXED_PMC_CTRL(i, FIXED_PMC_KERNEL)); wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, FIXED_PMC_GLOBAL_CTRL_ENABLE(i)); __asm__ __volatile__("loop ." : "+c"((int){NUM_BRANCHES})); wrmsr(MSR_CORE_PERF_GLOBAL_CTRL, 0); val = rdmsr(MSR_CORE_PERF_FIXED_CTR0 + i); GUEST_ASSERT_NE(val, 0); } GUEST_DONE(); } static void test_fixed_counters(uint8_t pmu_version, uint64_t perf_capabilities, uint8_t nr_fixed_counters, uint32_t supported_bitmask) { struct kvm_vcpu *vcpu; struct kvm_vm *vm; vm = pmu_vm_create_with_one_vcpu(&vcpu, guest_test_fixed_counters, pmu_version, perf_capabilities); vcpu_set_cpuid_property(vcpu, X86_PROPERTY_PMU_FIXED_COUNTERS_BITMASK, supported_bitmask); vcpu_set_cpuid_property(vcpu, X86_PROPERTY_PMU_NR_FIXED_COUNTERS, nr_fixed_counters); run_vcpu(vcpu); kvm_vm_free(vm); } static void test_intel_counters(void) { uint8_t nr_arch_events = kvm_cpu_property(X86_PROPERTY_PMU_EBX_BIT_VECTOR_LENGTH); uint8_t nr_fixed_counters = kvm_cpu_property(X86_PROPERTY_PMU_NR_FIXED_COUNTERS); uint8_t nr_gp_counters = kvm_cpu_property(X86_PROPERTY_PMU_NR_GP_COUNTERS); uint8_t pmu_version = kvm_cpu_property(X86_PROPERTY_PMU_VERSION); unsigned int i; uint8_t v, j; uint32_t k; const uint64_t perf_caps[] = { 0, PMU_CAP_FW_WRITES, }; /* * Test up to PMU v5, which is the current maximum version defined by * Intel, i.e. is the last version that is guaranteed to be backwards * compatible with KVM's existing behavior. */ uint8_t max_pmu_version = max_t(typeof(pmu_version), pmu_version, 5); /* * Detect the existence of events that aren't supported by selftests. * This will (obviously) fail any time the kernel adds support for a * new event, but it's worth paying that price to keep the test fresh. */ TEST_ASSERT(nr_arch_events <= NR_INTEL_ARCH_EVENTS, "New architectural event(s) detected; please update this test (length = %u, mask = %x)", nr_arch_events, kvm_cpu_property(X86_PROPERTY_PMU_EVENTS_MASK)); /* * Force iterating over known arch events regardless of whether or not * KVM/hardware supports a given event. */ nr_arch_events = max_t(typeof(nr_arch_events), nr_arch_events, NR_INTEL_ARCH_EVENTS); for (v = 0; v <= max_pmu_version; v++) { for (i = 0; i < ARRAY_SIZE(perf_caps); i++) { if (!kvm_has_perf_caps && perf_caps[i]) continue; pr_info("Testing arch events, PMU version %u, perf_caps = %lx\n", v, perf_caps[i]); /* * To keep the total runtime reasonable, test every * possible non-zero, non-reserved bitmap combination * only with the native PMU version and the full bit * vector length. */ if (v == pmu_version) { for (k = 1; k < (BIT(nr_arch_events) - 1); k++) test_arch_events(v, perf_caps[i], nr_arch_events, k); } /* * Test single bits for all PMU version and lengths up * the number of events +1 (to verify KVM doesn't do * weird things if the guest length is greater than the * host length). Explicitly test a mask of '0' and all * ones i.e. all events being available and unavailable. */ for (j = 0; j <= nr_arch_events + 1; j++) { test_arch_events(v, perf_caps[i], j, 0); test_arch_events(v, perf_caps[i], j, 0xff); for (k = 0; k < nr_arch_events; k++) test_arch_events(v, perf_caps[i], j, BIT(k)); } pr_info("Testing GP counters, PMU version %u, perf_caps = %lx\n", v, perf_caps[i]); for (j = 0; j <= nr_gp_counters; j++) test_gp_counters(v, perf_caps[i], j); pr_info("Testing fixed counters, PMU version %u, perf_caps = %lx\n", v, perf_caps[i]); for (j = 0; j <= nr_fixed_counters; j++) { for (k = 0; k <= (BIT(nr_fixed_counters) - 1); k++) test_fixed_counters(v, perf_caps[i], j, k); } } } } int main(int argc, char *argv[]) { TEST_REQUIRE(kvm_is_pmu_enabled()); TEST_REQUIRE(host_cpu_is_intel); TEST_REQUIRE(kvm_cpu_has_p(X86_PROPERTY_PMU_VERSION)); TEST_REQUIRE(kvm_cpu_property(X86_PROPERTY_PMU_VERSION) > 0); kvm_pmu_version = kvm_cpu_property(X86_PROPERTY_PMU_VERSION); kvm_has_perf_caps = kvm_cpu_has(X86_FEATURE_PDCM); is_forced_emulation_enabled = kvm_is_forced_emulation_enabled(); test_intel_counters(); return 0; } |