From patchwork Mon Jun 13 13:38:53 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vitaly Kuznetsov X-Patchwork-Id: 12879835 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 163BDCCA47B for ; Mon, 13 Jun 2022 17:56:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239612AbiFMRzb (ORCPT ); Mon, 13 Jun 2022 13:55:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243280AbiFMRyd (ORCPT ); Mon, 13 Jun 2022 13:54:33 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 8F42E3DA5D for ; Mon, 13 Jun 2022 06:39:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1655127596; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=K+AbiDvOnXf/VI9tuRodU8wPU/El8Y5Fo37NPhCtIeA=; b=Pqc+z8DIak2iLCzrDil4ulbv28PzPYzISisy+FRqnw0DLvSDTQmuvIkMJpvFhKpck1uhYJ xLIOy2QW4c17/twNXI2q+n1NWzPKCQ2ffa7uezAqAw7P0eW+uc0cRLEWlpTcWMkDPHZ2xQ MH7O8kpqckW0Of2I88Z8LsPU+q2a9pI= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-638-GRCPRKoPM7-N-6X_JTp0NA-1; Mon, 13 Jun 2022 09:39:54 -0400 X-MC-Unique: GRCPRKoPM7-N-6X_JTp0NA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id B98C43C1104F; Mon, 13 Jun 2022 13:39:53 +0000 (UTC) Received: from fedora.redhat.com (unknown [10.40.194.60]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0DA46492CA2; Mon, 13 Jun 2022 13:39:50 +0000 (UTC) From: Vitaly Kuznetsov To: kvm@vger.kernel.org, Paolo Bonzini Cc: Sean Christopherson , Maxim Levitsky , Wanpeng Li , Jim Mattson , Michael Kelley , Siddharth Chandrasekaran , Yuan Yao , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v7 10/39] KVM: x86: hyper-v: Don't use sparse_set_to_vcpu_mask() in kvm_hv_send_ipi() Date: Mon, 13 Jun 2022 15:38:53 +0200 Message-Id: <20220613133922.2875594-11-vkuznets@redhat.com> In-Reply-To: <20220613133922.2875594-1-vkuznets@redhat.com> References: <20220613133922.2875594-1-vkuznets@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Get rid of on-stack allocation of vcpu_mask and optimize kvm_hv_send_ipi() for a smaller number of vCPUs in the request. When Hyper-V TLB flush is in use, HvSendSyntheticClusterIpi{,Ex} calls are not commonly used to send IPIs to a large number of vCPUs (and are rarely used in general). Introduce hv_is_vp_in_sparse_set() to directly check if the specified VP_ID is present in sparse vCPU set. Reviewed-by: Maxim Levitsky Signed-off-by: Vitaly Kuznetsov --- arch/x86/kvm/hyperv.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index f41153c71beb..269a5fcca31b 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1747,6 +1747,25 @@ static void sparse_set_to_vcpu_mask(struct kvm *kvm, u64 *sparse_banks, } } +static bool hv_is_vp_in_sparse_set(u32 vp_id, u64 valid_bank_mask, u64 sparse_banks[]) +{ + int bank, sbank = 0; + + if (!test_bit(vp_id / HV_VCPUS_PER_SPARSE_BANK, + (unsigned long *)&valid_bank_mask)) + return false; + + for_each_set_bit(bank, (unsigned long *)&valid_bank_mask, + KVM_HV_MAX_SPARSE_VCPU_SET_BITS) { + if (bank == vp_id / HV_VCPUS_PER_SPARSE_BANK) + break; + sbank++; + } + + return test_bit(vp_id % HV_VCPUS_PER_SPARSE_BANK, + (unsigned long *)&sparse_banks[sbank]); +} + struct kvm_hv_hcall { u64 param; u64 ingpa; @@ -2029,8 +2048,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc) ((u64)hc->rep_cnt << HV_HYPERCALL_REP_COMP_OFFSET); } -static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector, - unsigned long *vcpu_bitmap) +static void kvm_hv_send_ipi_to_many(struct kvm *kvm, u32 vector, + u64 *sparse_banks, u64 valid_bank_mask) { struct kvm_lapic_irq irq = { .delivery_mode = APIC_DM_FIXED, @@ -2040,7 +2059,10 @@ static void kvm_send_ipi_to_many(struct kvm *kvm, u32 vector, unsigned long i; kvm_for_each_vcpu(i, vcpu, kvm) { - if (vcpu_bitmap && !test_bit(i, vcpu_bitmap)) + if (sparse_banks && + !hv_is_vp_in_sparse_set(kvm_hv_get_vpindex(vcpu), + valid_bank_mask, + sparse_banks)) continue; /* We fail only when APIC is disabled */ @@ -2053,7 +2075,6 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc) struct kvm *kvm = vcpu->kvm; struct hv_send_ipi_ex send_ipi_ex; struct hv_send_ipi send_ipi; - DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS); u64 valid_bank_mask; u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS]; u32 vector; @@ -2115,13 +2136,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc) if ((vector < HV_IPI_LOW_VECTOR) || (vector > HV_IPI_HIGH_VECTOR)) return HV_STATUS_INVALID_HYPERCALL_INPUT; - if (all_cpus) { - kvm_send_ipi_to_many(kvm, vector, NULL); - } else { - sparse_set_to_vcpu_mask(kvm, sparse_banks, valid_bank_mask, vcpu_mask); - - kvm_send_ipi_to_many(kvm, vector, vcpu_mask); - } + kvm_hv_send_ipi_to_many(kvm, vector, all_cpus ? NULL : sparse_banks, valid_bank_mask); ret_success: return HV_STATUS_SUCCESS;