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-rw-r--r--arch/x86/kvm/pmu_intel.c358
1 files changed, 358 insertions, 0 deletions
diff --git a/arch/x86/kvm/pmu_intel.c b/arch/x86/kvm/pmu_intel.c
new file mode 100644
index 000000000000..ab38af4f4947
--- /dev/null
+++ b/arch/x86/kvm/pmu_intel.c
@@ -0,0 +1,358 @@
+/*
+ * KVM PMU support for Intel CPUs
+ *
+ * Copyright 2011 Red Hat, Inc. and/or its affiliates.
+ *
+ * Authors:
+ * Avi Kivity <avi@redhat.com>
+ * Gleb Natapov <gleb@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+#include <linux/types.h>
+#include <linux/kvm_host.h>
+#include <linux/perf_event.h>
+#include <asm/perf_event.h>
+#include "x86.h"
+#include "cpuid.h"
+#include "lapic.h"
+#include "pmu.h"
+
+static struct kvm_event_hw_type_mapping intel_arch_events[] = {
+ /* Index must match CPUID 0x0A.EBX bit vector */
+ [0] = { 0x3c, 0x00, PERF_COUNT_HW_CPU_CYCLES },
+ [1] = { 0xc0, 0x00, PERF_COUNT_HW_INSTRUCTIONS },
+ [2] = { 0x3c, 0x01, PERF_COUNT_HW_BUS_CYCLES },
+ [3] = { 0x2e, 0x4f, PERF_COUNT_HW_CACHE_REFERENCES },
+ [4] = { 0x2e, 0x41, PERF_COUNT_HW_CACHE_MISSES },
+ [5] = { 0xc4, 0x00, PERF_COUNT_HW_BRANCH_INSTRUCTIONS },
+ [6] = { 0xc5, 0x00, PERF_COUNT_HW_BRANCH_MISSES },
+ [7] = { 0x00, 0x30, PERF_COUNT_HW_REF_CPU_CYCLES },
+};
+
+/* mapping between fixed pmc index and intel_arch_events array */
+static int fixed_pmc_events[] = {1, 0, 7};
+
+static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
+{
+ int i;
+
+ for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
+ u8 new_ctrl = fixed_ctrl_field(data, i);
+ u8 old_ctrl = fixed_ctrl_field(pmu->fixed_ctr_ctrl, i);
+ struct kvm_pmc *pmc;
+
+ pmc = get_fixed_pmc(pmu, MSR_CORE_PERF_FIXED_CTR0 + i);
+
+ if (old_ctrl == new_ctrl)
+ continue;
+
+ reprogram_fixed_counter(pmc, new_ctrl, i);
+ }
+
+ pmu->fixed_ctr_ctrl = data;
+}
+
+/* function is called when global control register has been updated. */
+static void global_ctrl_changed(struct kvm_pmu *pmu, u64 data)
+{
+ int bit;
+ u64 diff = pmu->global_ctrl ^ data;
+
+ pmu->global_ctrl = data;
+
+ for_each_set_bit(bit, (unsigned long *)&diff, X86_PMC_IDX_MAX)
+ reprogram_counter(pmu, bit);
+}
+
+static unsigned intel_find_arch_event(struct kvm_pmu *pmu,
+ u8 event_select,
+ u8 unit_mask)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(intel_arch_events); i++)
+ if (intel_arch_events[i].eventsel == event_select
+ && intel_arch_events[i].unit_mask == unit_mask
+ && (pmu->available_event_types & (1 << i)))
+ break;
+
+ if (i == ARRAY_SIZE(intel_arch_events))
+ return PERF_COUNT_HW_MAX;
+
+ return intel_arch_events[i].event_type;
+}
+
+static unsigned intel_find_fixed_event(int idx)
+{
+ if (idx >= ARRAY_SIZE(fixed_pmc_events))
+ return PERF_COUNT_HW_MAX;
+
+ return intel_arch_events[fixed_pmc_events[idx]].event_type;
+}
+
+/* check if a PMC is enabled by comparising it with globl_ctrl bits. */
+static bool intel_pmc_is_enabled(struct kvm_pmc *pmc)
+{
+ struct kvm_pmu *pmu = pmc_to_pmu(pmc);
+
+ return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl);
+}
+
+static struct kvm_pmc *intel_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx)
+{
+ if (pmc_idx < INTEL_PMC_IDX_FIXED)
+ return get_gp_pmc(pmu, MSR_P6_EVNTSEL0 + pmc_idx,
+ MSR_P6_EVNTSEL0);
+ else {
+ u32 idx = pmc_idx - INTEL_PMC_IDX_FIXED;
+
+ return get_fixed_pmc(pmu, idx + MSR_CORE_PERF_FIXED_CTR0);
+ }
+}
+
+/* returns 0 if idx's corresponding MSR exists; otherwise returns 1. */
+static int intel_is_valid_msr_idx(struct kvm_vcpu *vcpu, unsigned idx)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ bool fixed = idx & (1u << 30);
+
+ idx &= ~(3u << 30);
+
+ return (!fixed && idx >= pmu->nr_arch_gp_counters) ||
+ (fixed && idx >= pmu->nr_arch_fixed_counters);
+}
+
+static struct kvm_pmc *intel_msr_idx_to_pmc(struct kvm_vcpu *vcpu,
+ unsigned idx)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ bool fixed = idx & (1u << 30);
+ struct kvm_pmc *counters;
+
+ idx &= ~(3u << 30);
+ if (!fixed && idx >= pmu->nr_arch_gp_counters)
+ return NULL;
+ if (fixed && idx >= pmu->nr_arch_fixed_counters)
+ return NULL;
+ counters = fixed ? pmu->fixed_counters : pmu->gp_counters;
+
+ return &counters[idx];
+}
+
+static bool intel_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ int ret;
+
+ switch (msr) {
+ case MSR_CORE_PERF_FIXED_CTR_CTRL:
+ case MSR_CORE_PERF_GLOBAL_STATUS:
+ case MSR_CORE_PERF_GLOBAL_CTRL:
+ case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
+ ret = pmu->version > 1;
+ break;
+ default:
+ ret = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0) ||
+ get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0) ||
+ get_fixed_pmc(pmu, msr);
+ break;
+ }
+
+ return ret;
+}
+
+static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *data)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ struct kvm_pmc *pmc;
+
+ switch (msr) {
+ case MSR_CORE_PERF_FIXED_CTR_CTRL:
+ *data = pmu->fixed_ctr_ctrl;
+ return 0;
+ case MSR_CORE_PERF_GLOBAL_STATUS:
+ *data = pmu->global_status;
+ return 0;
+ case MSR_CORE_PERF_GLOBAL_CTRL:
+ *data = pmu->global_ctrl;
+ return 0;
+ case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
+ *data = pmu->global_ovf_ctrl;
+ return 0;
+ default:
+ if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
+ (pmc = get_fixed_pmc(pmu, msr))) {
+ *data = pmc_read_counter(pmc);
+ return 0;
+ } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
+ *data = pmc->eventsel;
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ struct kvm_pmc *pmc;
+ u32 msr = msr_info->index;
+ u64 data = msr_info->data;
+
+ switch (msr) {
+ case MSR_CORE_PERF_FIXED_CTR_CTRL:
+ if (pmu->fixed_ctr_ctrl == data)
+ return 0;
+ if (!(data & 0xfffffffffffff444ull)) {
+ reprogram_fixed_counters(pmu, data);
+ return 0;
+ }
+ break;
+ case MSR_CORE_PERF_GLOBAL_STATUS:
+ if (msr_info->host_initiated) {
+ pmu->global_status = data;
+ return 0;
+ }
+ break; /* RO MSR */
+ case MSR_CORE_PERF_GLOBAL_CTRL:
+ if (pmu->global_ctrl == data)
+ return 0;
+ if (!(data & pmu->global_ctrl_mask)) {
+ global_ctrl_changed(pmu, data);
+ return 0;
+ }
+ break;
+ case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
+ if (!(data & (pmu->global_ctrl_mask & ~(3ull<<62)))) {
+ if (!msr_info->host_initiated)
+ pmu->global_status &= ~data;
+ pmu->global_ovf_ctrl = data;
+ return 0;
+ }
+ break;
+ default:
+ if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
+ (pmc = get_fixed_pmc(pmu, msr))) {
+ if (!msr_info->host_initiated)
+ data = (s64)(s32)data;
+ pmc->counter += data - pmc_read_counter(pmc);
+ return 0;
+ } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
+ if (data == pmc->eventsel)
+ return 0;
+ if (!(data & pmu->reserved_bits)) {
+ reprogram_gp_counter(pmc, data);
+ return 0;
+ }
+ }
+ }
+
+ return 1;
+}
+
+static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ struct kvm_cpuid_entry2 *entry;
+ union cpuid10_eax eax;
+ union cpuid10_edx edx;
+
+ pmu->nr_arch_gp_counters = 0;
+ pmu->nr_arch_fixed_counters = 0;
+ pmu->counter_bitmask[KVM_PMC_GP] = 0;
+ pmu->counter_bitmask[KVM_PMC_FIXED] = 0;
+ pmu->version = 0;
+ pmu->reserved_bits = 0xffffffff00200000ull;
+
+ entry = kvm_find_cpuid_entry(vcpu, 0xa, 0);
+ if (!entry)
+ return;
+ eax.full = entry->eax;
+ edx.full = entry->edx;
+
+ pmu->version = eax.split.version_id;
+ if (!pmu->version)
+ return;
+
+ pmu->nr_arch_gp_counters = min_t(int, eax.split.num_counters,
+ INTEL_PMC_MAX_GENERIC);
+ pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << eax.split.bit_width) - 1;
+ pmu->available_event_types = ~entry->ebx &
+ ((1ull << eax.split.mask_length) - 1);
+
+ if (pmu->version == 1) {
+ pmu->nr_arch_fixed_counters = 0;
+ } else {
+ pmu->nr_arch_fixed_counters =
+ min_t(int, edx.split.num_counters_fixed,
+ INTEL_PMC_MAX_FIXED);
+ pmu->counter_bitmask[KVM_PMC_FIXED] =
+ ((u64)1 << edx.split.bit_width_fixed) - 1;
+ }
+
+ pmu->global_ctrl = ((1 << pmu->nr_arch_gp_counters) - 1) |
+ (((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED);
+ pmu->global_ctrl_mask = ~pmu->global_ctrl;
+
+ entry = kvm_find_cpuid_entry(vcpu, 7, 0);
+ if (entry &&
+ (boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM)) &&
+ (entry->ebx & (X86_FEATURE_HLE|X86_FEATURE_RTM)))
+ pmu->reserved_bits ^= HSW_IN_TX|HSW_IN_TX_CHECKPOINTED;
+}
+
+static void intel_pmu_init(struct kvm_vcpu *vcpu)
+{
+ int i;
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+
+ for (i = 0; i < INTEL_PMC_MAX_GENERIC; i++) {
+ pmu->gp_counters[i].type = KVM_PMC_GP;
+ pmu->gp_counters[i].vcpu = vcpu;
+ pmu->gp_counters[i].idx = i;
+ }
+
+ for (i = 0; i < INTEL_PMC_MAX_FIXED; i++) {
+ pmu->fixed_counters[i].type = KVM_PMC_FIXED;
+ pmu->fixed_counters[i].vcpu = vcpu;
+ pmu->fixed_counters[i].idx = i + INTEL_PMC_IDX_FIXED;
+ }
+}
+
+static void intel_pmu_reset(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ int i;
+
+ for (i = 0; i < INTEL_PMC_MAX_GENERIC; i++) {
+ struct kvm_pmc *pmc = &pmu->gp_counters[i];
+
+ pmc_stop_counter(pmc);
+ pmc->counter = pmc->eventsel = 0;
+ }
+
+ for (i = 0; i < INTEL_PMC_MAX_FIXED; i++)
+ pmc_stop_counter(&pmu->fixed_counters[i]);
+
+ pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status =
+ pmu->global_ovf_ctrl = 0;
+}
+
+struct kvm_pmu_ops intel_pmu_ops = {
+ .find_arch_event = intel_find_arch_event,
+ .find_fixed_event = intel_find_fixed_event,
+ .pmc_is_enabled = intel_pmc_is_enabled,
+ .pmc_idx_to_pmc = intel_pmc_idx_to_pmc,
+ .msr_idx_to_pmc = intel_msr_idx_to_pmc,
+ .is_valid_msr_idx = intel_is_valid_msr_idx,
+ .is_valid_msr = intel_is_valid_msr,
+ .get_msr = intel_pmu_get_msr,
+ .set_msr = intel_pmu_set_msr,
+ .refresh = intel_pmu_refresh,
+ .init = intel_pmu_init,
+ .reset = intel_pmu_reset,
+};