diff options
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 3 | ||||
| -rw-r--r-- | arch/x86/kvm/pmu.c | 75 | ||||
| -rw-r--r-- | arch/x86/kvm/pmu.h | 4 |
3 files changed, 61 insertions, 21 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index f19a76d3ca0e..d7680612ba1e 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -579,6 +579,9 @@ struct kvm_pmu { DECLARE_BITMAP(all_valid_pmc_idx, X86_PMC_IDX_MAX); DECLARE_BITMAP(pmc_in_use, X86_PMC_IDX_MAX); + DECLARE_BITMAP(pmc_counting_instructions, X86_PMC_IDX_MAX); + DECLARE_BITMAP(pmc_counting_branches, X86_PMC_IDX_MAX); + u64 ds_area; u64 pebs_enable; u64 pebs_enable_rsvd; diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c index 9040bf20e851..8070097c5c4a 100644 --- a/arch/x86/kvm/pmu.c +++ b/arch/x86/kvm/pmu.c @@ -542,6 +542,47 @@ static int reprogram_counter(struct kvm_pmc *pmc) eventsel & ARCH_PERFMON_EVENTSEL_INT); } +static bool pmc_is_event_match(struct kvm_pmc *pmc, u64 eventsel) +{ + /* + * Ignore checks for edge detect (all events currently emulated by KVM + * are always rising edges), pin control (unsupported by modern CPUs), + * and counter mask and its invert flag (KVM doesn't emulate multiple + * events in a single clock cycle). + * + * Note, the uppermost nibble of AMD's mask overlaps Intel's IN_TX (bit + * 32) and IN_TXCP (bit 33), as well as two reserved bits (bits 35:34). + * Checking the "in HLE/RTM transaction" flags is correct as the vCPU + * can't be in a transaction if KVM is emulating an instruction. + * + * Checking the reserved bits might be wrong if they are defined in the + * future, but so could ignoring them, so do the simple thing for now. + */ + return !((pmc->eventsel ^ eventsel) & AMD64_RAW_EVENT_MASK_NB); +} + +void kvm_pmu_recalc_pmc_emulation(struct kvm_pmu *pmu, struct kvm_pmc *pmc) +{ + bitmap_clear(pmu->pmc_counting_instructions, pmc->idx, 1); + bitmap_clear(pmu->pmc_counting_branches, pmc->idx, 1); + + /* + * Do NOT consult the PMU event filters, as the filters must be checked + * at the time of emulation to ensure KVM uses fresh information, e.g. + * omitting a PMC from a bitmap could result in a missed event if the + * filter is changed to allow counting the event. + */ + if (!pmc_speculative_in_use(pmc)) + return; + + if (pmc_is_event_match(pmc, kvm_pmu_eventsel.INSTRUCTIONS_RETIRED)) + bitmap_set(pmu->pmc_counting_instructions, pmc->idx, 1); + + if (pmc_is_event_match(pmc, kvm_pmu_eventsel.BRANCH_INSTRUCTIONS_RETIRED)) + bitmap_set(pmu->pmc_counting_branches, pmc->idx, 1); +} +EXPORT_SYMBOL_GPL(kvm_pmu_recalc_pmc_emulation); + void kvm_pmu_handle_event(struct kvm_vcpu *vcpu) { DECLARE_BITMAP(bitmap, X86_PMC_IDX_MAX); @@ -577,6 +618,9 @@ void kvm_pmu_handle_event(struct kvm_vcpu *vcpu) */ if (unlikely(pmu->need_cleanup)) kvm_pmu_cleanup(vcpu); + + kvm_for_each_pmc(pmu, pmc, bit, bitmap) + kvm_pmu_recalc_pmc_emulation(pmu, pmc); } int kvm_pmu_check_rdpmc_early(struct kvm_vcpu *vcpu, unsigned int idx) @@ -915,7 +959,8 @@ static inline bool cpl_is_matched(struct kvm_pmc *pmc) select_user; } -static void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 eventsel) +static void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, + const unsigned long *event_pmcs) { DECLARE_BITMAP(bitmap, X86_PMC_IDX_MAX); struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); @@ -924,29 +969,17 @@ static void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 eventsel) BUILD_BUG_ON(sizeof(pmu->global_ctrl) * BITS_PER_BYTE != X86_PMC_IDX_MAX); + if (bitmap_empty(event_pmcs, X86_PMC_IDX_MAX)) + return; + if (!kvm_pmu_has_perf_global_ctrl(pmu)) - bitmap_copy(bitmap, pmu->all_valid_pmc_idx, X86_PMC_IDX_MAX); - else if (!bitmap_and(bitmap, pmu->all_valid_pmc_idx, + bitmap_copy(bitmap, event_pmcs, X86_PMC_IDX_MAX); + else if (!bitmap_and(bitmap, event_pmcs, (unsigned long *)&pmu->global_ctrl, X86_PMC_IDX_MAX)) return; kvm_for_each_pmc(pmu, pmc, i, bitmap) { - /* - * Ignore checks for edge detect (all events currently emulated - * but KVM are always rising edges), pin control (unsupported - * by modern CPUs), and counter mask and its invert flag (KVM - * doesn't emulate multiple events in a single clock cycle). - * - * Note, the uppermost nibble of AMD's mask overlaps Intel's - * IN_TX (bit 32) and IN_TXCP (bit 33), as well as two reserved - * bits (bits 35:34). Checking the "in HLE/RTM transaction" - * flags is correct as the vCPU can't be in a transaction if - * KVM is emulating an instruction. Checking the reserved bits - * might be wrong if they are defined in the future, but so - * could ignoring them, so do the simple thing for now. - */ - if (((pmc->eventsel ^ eventsel) & AMD64_RAW_EVENT_MASK_NB) || - !pmc_event_is_allowed(pmc) || !cpl_is_matched(pmc)) + if (!pmc_event_is_allowed(pmc) || !cpl_is_matched(pmc)) continue; kvm_pmu_incr_counter(pmc); @@ -955,13 +988,13 @@ static void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 eventsel) void kvm_pmu_instruction_retired(struct kvm_vcpu *vcpu) { - kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.INSTRUCTIONS_RETIRED); + kvm_pmu_trigger_event(vcpu, vcpu_to_pmu(vcpu)->pmc_counting_instructions); } EXPORT_SYMBOL_GPL(kvm_pmu_instruction_retired); void kvm_pmu_branch_retired(struct kvm_vcpu *vcpu) { - kvm_pmu_trigger_event(vcpu, kvm_pmu_eventsel.BRANCH_INSTRUCTIONS_RETIRED); + kvm_pmu_trigger_event(vcpu, vcpu_to_pmu(vcpu)->pmc_counting_branches); } EXPORT_SYMBOL_GPL(kvm_pmu_branch_retired); diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h index 740af816af37..cb93a936a177 100644 --- a/arch/x86/kvm/pmu.h +++ b/arch/x86/kvm/pmu.h @@ -176,8 +176,12 @@ extern struct x86_pmu_capability kvm_pmu_cap; void kvm_init_pmu_capability(const struct kvm_pmu_ops *pmu_ops); +void kvm_pmu_recalc_pmc_emulation(struct kvm_pmu *pmu, struct kvm_pmc *pmc); + static inline void kvm_pmu_request_counter_reprogram(struct kvm_pmc *pmc) { + kvm_pmu_recalc_pmc_emulation(pmc_to_pmu(pmc), pmc); + set_bit(pmc->idx, pmc_to_pmu(pmc)->reprogram_pmi); kvm_make_request(KVM_REQ_PMU, pmc->vcpu); } |
