From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754864AbeDPLIY (ORCPT ); Mon, 16 Apr 2018 07:08:24 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:54318 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754845AbeDPLIU (ORCPT ); Mon, 16 Apr 2018 07:08:20 -0400 From: Vitaly Kuznetsov To: kvm@vger.kernel.org Cc: x86@kernel.org, Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Roman Kagan , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , "Michael Kelley (EOSG)" , Mohammed Gamal , Cathy Avery , linux-kernel@vger.kernel.org Subject: [PATCH v3 5/6] KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX implementation Date: Mon, 16 Apr 2018 13:08:05 +0200 Message-Id: <20180416110806.4896-6-vkuznets@redhat.com> In-Reply-To: <20180416110806.4896-1-vkuznets@redhat.com> References: <20180416110806.4896-1-vkuznets@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Implement HvFlushVirtualAddress{List,Space}Ex hypercalls in a simplistic way: do full TLB flush with KVM_REQ_TLB_FLUSH and kick vCPUs which are currently IN_GUEST_MODE. Signed-off-by: Vitaly Kuznetsov --- arch/x86/kvm/hyperv.c | 116 ++++++++++++++++++++++++++++++++++++++++++++++++++ arch/x86/kvm/trace.h | 27 ++++++++++++ 2 files changed, 143 insertions(+) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index fa26af1e8b7c..7028cd58d5f4 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1301,6 +1301,108 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa, ((u64)rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET); } +static __always_inline int get_sparse_bank_no(u64 valid_bank_mask, int bank_no) +{ + int i = 0, j; + + if (!(valid_bank_mask & BIT_ULL(bank_no))) + return -1; + + for (j = 0; j < bank_no; j++) + if (valid_bank_mask & BIT_ULL(j)) + i++; + + return i; +} + +static __always_inline int load_bank_guest(struct kvm *kvm, u64 ingpa, + int sparse_bank, u64 *bank_contents) +{ + int offset; + + offset = offsetof(struct hv_tlb_flush_ex, hv_vp_set.bank_contents) + + sizeof(u64) * sparse_bank; + + if (unlikely(kvm_read_guest(kvm, ingpa + offset, + bank_contents, sizeof(u64)))) + return 1; + + return 0; +} + +static int kvm_hv_flush_tlb_ex(struct kvm_vcpu *current_vcpu, u64 ingpa, + u16 rep_cnt) +{ + struct kvm *kvm = current_vcpu->kvm; + struct kvm_vcpu_hv *hv_current = ¤t_vcpu->arch.hyperv; + struct hv_tlb_flush_ex flush; + struct kvm_vcpu *vcpu; + u64 bank_contents, valid_bank_mask; + int i, cpu, me, current_sparse_bank = -1; + u64 ret = HV_STATUS_INVALID_HYPERCALL_INPUT; + + if (unlikely(kvm_read_guest(kvm, ingpa, &flush, sizeof(flush)))) + return ret; + + valid_bank_mask = flush.hv_vp_set.valid_bank_mask; + + trace_kvm_hv_flush_tlb_ex(valid_bank_mask, flush.hv_vp_set.format, + flush.address_space, flush.flags); + + cpumask_clear(&hv_current->tlb_lush); + + me = get_cpu(); + + kvm_for_each_vcpu(i, vcpu, kvm) { + struct kvm_vcpu_hv *hv = &vcpu->arch.hyperv; + int bank = hv->vp_index / 64, sparse_bank; + + if (flush.hv_vp_set.format == HV_GENERIC_SET_SPARCE_4K) { + /* Check is the bank of this vCPU is in sparse set */ + sparse_bank = get_sparse_bank_no(valid_bank_mask, bank); + if (sparse_bank < 0) + continue; + + /* + * Assume hv->vp_index is in ascending order and we can + * optimize by not reloading bank contents for every + * vCPU. + */ + if (sparse_bank != current_sparse_bank) { + if (load_bank_guest(kvm, ingpa, sparse_bank, + &bank_contents)) + return ret; + current_sparse_bank = sparse_bank; + } + + if (!(bank_contents & BIT_ULL(hv->vp_index % 64))) + continue; + } + + kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); + + /* + * It is possible that vCPU will migrate and we will kick wrong + * CPU but vCPU's TLB will anyway be flushed upon migration as + * we already made KVM_REQ_TLB_FLUSH request. + */ + cpu = vcpu->cpu; + if (cpu != -1 && cpu != me && cpu_online(cpu) && + kvm_arch_vcpu_should_kick(vcpu)) + cpumask_set_cpu(cpu, &hv_current->tlb_lush); + } + + if (!cpumask_empty(&hv_current->tlb_lush)) + smp_call_function_many(&hv_current->tlb_lush, ack_flush, + NULL, true); + + put_cpu(); + + /* We always do full TLB flush, set rep_done = rep_cnt. */ + return (u64)HV_STATUS_SUCCESS | + ((u64)rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET); +} + bool kvm_hv_hypercall_enabled(struct kvm *kvm) { return READ_ONCE(kvm->arch.hyperv.hv_hypercall) & HV_X64_MSR_HYPERCALL_ENABLE; @@ -1450,6 +1552,20 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) } ret = kvm_hv_flush_tlb(vcpu, ingpa, rep_cnt); break; + case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX: + if (unlikely(fast || !rep_cnt || rep_idx)) { + ret = HV_STATUS_INVALID_HYPERCALL_INPUT; + break; + } + ret = kvm_hv_flush_tlb_ex(vcpu, ingpa, rep_cnt); + break; + case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX: + if (unlikely(fast || rep)) { + ret = HV_STATUS_INVALID_HYPERCALL_INPUT; + break; + } + ret = kvm_hv_flush_tlb_ex(vcpu, ingpa, rep_cnt); + break; default: ret = HV_STATUS_INVALID_HYPERCALL_CODE; break; diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h index 47a4fd758743..0f997683404f 100644 --- a/arch/x86/kvm/trace.h +++ b/arch/x86/kvm/trace.h @@ -1391,6 +1391,33 @@ TRACE_EVENT(kvm_hv_flush_tlb, __entry->processor_mask, __entry->address_space, __entry->flags) ); + +/* + * Tracepoint for kvm_hv_flush_tlb_ex. + */ +TRACE_EVENT(kvm_hv_flush_tlb_ex, + TP_PROTO(u64 valid_bank_mask, u64 format, u64 address_space, u64 flags), + TP_ARGS(valid_bank_mask, format, address_space, flags), + + TP_STRUCT__entry( + __field(u64, valid_bank_mask) + __field(u64, format) + __field(u64, address_space) + __field(u64, flags) + ), + + TP_fast_assign( + __entry->valid_bank_mask = valid_bank_mask; + __entry->format = format; + __entry->address_space = address_space; + __entry->flags = flags; + ), + + TP_printk("valid_bank_mask 0x%llx format 0x%llx " + "address_space 0x%llx flags 0x%llx", + __entry->valid_bank_mask, __entry->format, + __entry->address_space, __entry->flags) +); #endif /* _TRACE_KVM_H */ #undef TRACE_INCLUDE_PATH -- 2.14.3