1 files changed, 374 insertions, 0 deletions
diff --git a/arch/x86/kvm/pmu_intel.c b/arch/x86/kvm/pmu_intel.c
new file mode 100644
index 000000000..611f9e60f
--- /dev/null
+++ b/arch/x86/kvm/pmu_intel.c
@@ -0,0 +1,374 @@
+/*
+ * 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, 0x03, 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)
+{
+	u32 event;
+	size_t size = ARRAY_SIZE(fixed_pmc_events);
+
+	if (idx >= size)
+		return PERF_COUNT_HW_MAX;
+
+	event = fixed_pmc_events[array_index_nospec(idx, size)];
+	return intel_arch_events[event].event_type;
+}
+
+/* check if a PMC is enabled by comparing 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, u64 *mask)
+{
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+	bool fixed = idx & (1u << 30);
+	struct kvm_pmc *counters;
+	unsigned int num_counters;
+
+	idx &= ~(3u << 30);
+	if (fixed) {
+		counters = pmu->fixed_counters;
+		num_counters = pmu->nr_arch_fixed_counters;
+	} else {
+		counters = pmu->gp_counters;
+		num_counters = pmu->nr_arch_gp_counters;
+	}
+	if (idx >= num_counters)
+		return NULL;
+	*mask &= pmu->counter_bitmask[fixed ? KVM_PMC_FIXED : KVM_PMC_GP];
+	return &counters[array_index_nospec(idx, num_counters)];
+}
+
+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))) {
+			u64 val = pmc_read_counter(pmc);
+			*data = val & pmu->counter_bitmask[KVM_PMC_GP];
+			return 0;
+		} else if ((pmc = get_fixed_pmc(pmu, msr))) {
+			u64 val = pmc_read_counter(pmc);
+			*data = val & pmu->counter_bitmask[KVM_PMC_FIXED];
+			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))) {
+			if (msr_info->host_initiated)
+				pmc->counter = data;
+			else
+				pmc->counter = (s32)data;
+			return 0;
+		} else if ((pmc = get_fixed_pmc(pmu, msr))) {
+			pmc->counter = data;
+			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 = ((1ull << 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,
+};