diff options
Diffstat (limited to 'arch/x86/kvm/pmu_intel.c')
-rw-r--r-- | arch/x86/kvm/pmu_intel.c | 358 |
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 000000000..ab38af4f4 --- /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, +}; |