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Diffstat (limited to 'tools/testing/selftests/kvm/x86_64/pmu_counters_test.c')
-rw-r--r--tools/testing/selftests/kvm/x86_64/pmu_counters_test.c620
1 files changed, 620 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c b/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c
new file mode 100644
index 000000000000..29609b52f8fa
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/pmu_counters_test.c
@@ -0,0 +1,620 @@
+// 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 nr_gp_counters = 0;
+ uint32_t base_msr;
+
+ if (guest_get_pmu_version())
+ nr_gp_counters = this_cpu_property(X86_PROPERTY_PMU_NR_GP_COUNTERS);
+
+ 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;
+}