From mboxrd@z Thu Jan 1 00:00:00 1970 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 D4A77C43334 for ; Tue, 7 Jun 2022 09:48:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240127AbiFGJsp (ORCPT ); Tue, 7 Jun 2022 05:48:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38304 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240020AbiFGJsT (ORCPT ); Tue, 7 Jun 2022 05:48:19 -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 51A3AE732B for ; Tue, 7 Jun 2022 02:48:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1654595295; 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=IFV6m742eJK5fjIllJH8j+SCBmQdPpQ1B+N/I8SMuIc=; b=fsCHB+lvJvmuySj2batn5E2zz/9coofIfNjFTOKVsHuzQW208ZwlIqvGNauGjDZgF19suH qb40Gk0M/+7GYhIBu0u4k2ywPvo1jg0gHecwfQCRwNGgok2RZLq9LkjxxwSo+w4Uq5K+Vk WTwM1Tu9sJfHVP54c9hWGhMCquLMngI= Received: from mail-qv1-f70.google.com (mail-qv1-f70.google.com [209.85.219.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-398-rWl89KHAMSa0ZQn2OR3AJQ-1; Tue, 07 Jun 2022 05:48:14 -0400 X-MC-Unique: rWl89KHAMSa0ZQn2OR3AJQ-1 Received: by mail-qv1-f70.google.com with SMTP id v15-20020ad4554f000000b004646455c054so10494646qvy.10 for ; Tue, 07 Jun 2022 02:48:14 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:user-agent:mime-version:content-transfer-encoding; bh=IFV6m742eJK5fjIllJH8j+SCBmQdPpQ1B+N/I8SMuIc=; b=Px0V9gr0a2Ewa9wPc6GPEypbt34jHHP70HXFtPw22sgTCe5+Jb188iWQD8SRvTc/ah 3+iqC1ec6g/XkTV8HKG4ZO55IlOuzcC1iKmiJqloUTnFX4cjg24GTn+LHxY5ZgmQoXbH rtrtcfXElkPs0IPoTxcRSnFYUTluxrGvkSurwNEi2BvcDxdKtqZ/x+RfxZmM1AdpS6M0 Lc6DLrPvP7/fnQqRDZcUoQWYylJxM03YtLu3jIHz2urVBokV/NIW2rWJyZfnXCCwTZiQ RFrJD0Gycj5TiQ/2PnOqSQKpWCZOc7h6KExptahhwhcGMjbSkk4yhPMuTBvPIrKmOpSs fOXg== X-Gm-Message-State: AOAM5312BpjBPMfPszmUX8MjWhOvrX/PzKZh5DTBillPl0NHH1LsZqge Atdp9mScmvVhbJ1XGoQOovP3zRHN5PoeGO1IUJSHAbdObDEJys0UCWxj4SScoHnQCUBM9uCX8Wp LAmj/ZPFALayL0PD++35zJ46i X-Received: by 2002:a37:a0c1:0:b0:6a6:9647:3548 with SMTP id j184-20020a37a0c1000000b006a696473548mr14546091qke.155.1654595293851; Tue, 07 Jun 2022 02:48:13 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwvMMVQxxX5Pf8YRgVde+mcpTypTBPlxZsx8/NMqJEuNU630kVMBm8gKxAIEY9Kf36NXraa7w== X-Received: by 2002:a37:a0c1:0:b0:6a6:9647:3548 with SMTP id j184-20020a37a0c1000000b006a696473548mr14546084qke.155.1654595293650; Tue, 07 Jun 2022 02:48:13 -0700 (PDT) Received: from [10.35.4.238] (bzq-82-81-161-50.red.bezeqint.net. [82.81.161.50]) by smtp.gmail.com with ESMTPSA id d19-20020a05620a241300b006a6c230f5e0sm4256533qkn.31.2022.06.07.02.48.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Jun 2022 02:48:13 -0700 (PDT) Message-ID: <9df598de5072fdbc6606363f0a75f6f0bea6fd60.camel@redhat.com> Subject: Re: [PATCH v6 18/38] KVM: x86: hyper-v: Introduce fast guest_hv_cpuid_has_l2_tlb_flush() check From: Maxim Levitsky To: Vitaly Kuznetsov , kvm@vger.kernel.org, Paolo Bonzini Cc: Sean Christopherson , Wanpeng Li , Jim Mattson , Michael Kelley , Siddharth Chandrasekaran , Yuan Yao , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Date: Tue, 07 Jun 2022 12:48:09 +0300 In-Reply-To: <20220606083655.2014609-19-vkuznets@redhat.com> References: <20220606083655.2014609-1-vkuznets@redhat.com> <20220606083655.2014609-19-vkuznets@redhat.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.40.4 (3.40.4-2.fc34) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2022-06-06 at 10:36 +0200, Vitaly Kuznetsov wrote: > Introduce a helper to quickly check if KVM needs to handle VMCALL/VMMCALL > from L2 in L0 to process L2 TLB flush requests. > > Signed-off-by: Vitaly Kuznetsov > --- >  arch/x86/include/asm/kvm_host.h | 1 + >  arch/x86/kvm/hyperv.c           | 6 ++++++ >  arch/x86/kvm/hyperv.h           | 7 +++++++ >  3 files changed, 14 insertions(+) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 5d60c66ee0de..f9a34af0a5cc 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -642,6 +642,7 @@ struct kvm_vcpu_hv { >                 u32 enlightenments_eax; /* HYPERV_CPUID_ENLIGHTMENT_INFO.EAX */ >                 u32 enlightenments_ebx; /* HYPERV_CPUID_ENLIGHTMENT_INFO.EBX */ >                 u32 syndbg_cap_eax; /* HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES.EAX */ > +               u32 nested_features_eax; /* HYPERV_CPUID_NESTED_FEATURES.EAX */ >         } cpuid_cache; >   >         struct kvm_vcpu_hv_tlb_flush_fifo tlb_flush_fifo[HV_NR_TLB_FLUSH_FIFOS]; > diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c > index 740190917c1c..4396d75588d8 100644 > --- a/arch/x86/kvm/hyperv.c > +++ b/arch/x86/kvm/hyperv.c > @@ -2229,6 +2229,12 @@ void kvm_hv_set_cpuid(struct kvm_vcpu *vcpu) >                 hv_vcpu->cpuid_cache.syndbg_cap_eax = entry->eax; >         else >                 hv_vcpu->cpuid_cache.syndbg_cap_eax = 0; > + > +       entry = kvm_find_cpuid_entry(vcpu, HYPERV_CPUID_NESTED_FEATURES, 0); > +       if (entry) > +               hv_vcpu->cpuid_cache.nested_features_eax = entry->eax; > +       else > +               hv_vcpu->cpuid_cache.nested_features_eax = 0; >  } >   >  int kvm_hv_set_enforce_cpuid(struct kvm_vcpu *vcpu, bool enforce) > diff --git a/arch/x86/kvm/hyperv.h b/arch/x86/kvm/hyperv.h > index 7778b3a5913c..2aa6fb7fc599 100644 > --- a/arch/x86/kvm/hyperv.h > +++ b/arch/x86/kvm/hyperv.h > @@ -170,6 +170,13 @@ static inline void kvm_hv_vcpu_empty_flush_tlb(struct kvm_vcpu *vcpu, bool is_gu >         kfifo_reset_out(&tlb_flush_fifo->entries); >  } >   > +static inline bool guest_hv_cpuid_has_l2_tlb_flush(struct kvm_vcpu *vcpu) > +{ > +       struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); > + > +       return hv_vcpu && (hv_vcpu->cpuid_cache.nested_features_eax & HV_X64_NESTED_DIRECT_FLUSH); > +} > + >  static inline bool kvm_hv_is_tlb_flush_hcall(struct kvm_vcpu *vcpu) >  { >         struct kvm_vcpu_hv *hv_vcpu = to_hv_vcpu(vcpu); Reviewed-by: Maxim Levitsky Best regards, Maxim Levitsky