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 A78B5C41513 for ; Thu, 19 Oct 2023 08:43:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344986AbjJSInc (ORCPT ); Thu, 19 Oct 2023 04:43:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47450 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345121AbjJSInI (ORCPT ); Thu, 19 Oct 2023 04:43:08 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 690E6D56 for ; Thu, 19 Oct 2023 01:42:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1697704924; 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: in-reply-to:in-reply-to:references:references; bh=vGK+hSgFfYjiRKwMyBTzzh6ZEkWcBlSDg4646KYldsk=; b=QqKY2OWFAEH68SFQ1OJ3PiN03R+txtGgkUmJGC0KcRgUZpIX/ZMoMzV85piKgIwVEZ8VL/ WkGhqkqsHD8snf3coHadL1GCdujlMBn6irgPyk6o2KObm/WT9+8JpNMePNXAJ0Lfb75ENA 88B4EDxqnOGJqEIICa0cu96gE/KAAW4= Received: from mail-ej1-f71.google.com (mail-ej1-f71.google.com [209.85.218.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-503-LXUdJkkdPUmWA9UrEXDLBg-1; Thu, 19 Oct 2023 04:42:02 -0400 X-MC-Unique: LXUdJkkdPUmWA9UrEXDLBg-1 Received: by mail-ej1-f71.google.com with SMTP id a640c23a62f3a-9c15543088aso63095966b.1 for ; Thu, 19 Oct 2023 01:42:02 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697704921; x=1698309721; h=mime-version:message-id:date:references:in-reply-to:subject:cc:to :from:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=vGK+hSgFfYjiRKwMyBTzzh6ZEkWcBlSDg4646KYldsk=; b=ftSAn+wvaVbBhlfmRdmJI1pd6rD3i+uVRTVU+nxBQcC/uJp8sKbOLA8j24Lkj5Ilwz rUNr/UxSwFO8wgJQ/JGDWsoUXPRKoYoZEou9guiX9TVGmxltqQGi7UvQZnglu8KmPBGs +Bvy4Hxa3BHmgD2RzrmnbYJtWx1PVPW4ebSdoOQuY/QoRA5ZdTXl/RuIA4rxw3gG/vim n8ehd7iRfXLMs9JG7H2m/lJixsh62LdNPVZWs4cI8tN6ztMn7VmEbQ0iBUWcJWddMiTU O1o6Oa3GzuQ4SzEMxhIFOUc/e04Cxikdi7o8DFv1E5zlpbpCdcNV7YXTI4QZA6iOvLkH 2S1A== X-Gm-Message-State: AOJu0YwrsIVKsYoBjklFR7V6EBb0tT5rax+vQCLwlFexOj4lczgr5XYW hQDaJ/RI6EqJKtEWe0wSLvOdBbO2YX++6G0TwlQyv74uwfqNzbXPGIv4QlqaN9so0InC7cBKDgc XhYY2D8hvN37f82LhNgeRqXpkAkQXaLSnSeJaloT0ayOqMThdWxTE5BjB904h9MFi9FYrfzVl1n sy0tBCmK64 X-Received: by 2002:a17:906:7951:b0:9b2:be5e:3674 with SMTP id l17-20020a170906795100b009b2be5e3674mr1197950ejo.36.1697704921694; Thu, 19 Oct 2023 01:42:01 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGQ1BG4b6jNv9iIaBTLiXVkoHYtlB43Tr9jZFdJbu5AO5W4UbtvXIvAh56Wk8wNUVrypXZoPg== X-Received: by 2002:a17:906:7951:b0:9b2:be5e:3674 with SMTP id l17-20020a170906795100b009b2be5e3674mr1197925ejo.36.1697704921302; Thu, 19 Oct 2023 01:42:01 -0700 (PDT) Received: from fedora (g2.ign.cz. [91.219.240.8]) by smtp.gmail.com with ESMTPSA id y4-20020a1709064b0400b009b947aacb4bsm3117049eju.191.2023.10.19.01.42.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 19 Oct 2023 01:42:00 -0700 (PDT) From: Vitaly Kuznetsov To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] KVM: x86/mmu: Declare flush_remote_tlbs{_range}() hooks iff HYPERV!=n In-Reply-To: <20231018192325.1893896-1-seanjc@google.com> References: <20231018192325.1893896-1-seanjc@google.com> Date: Thu, 19 Oct 2023 10:41:59 +0200 Message-ID: <87wmvj57hk.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sean Christopherson writes: > Declare the kvm_x86_ops hooks used to wire up paravirt TLB flushes when > running under Hyper-V if and only if CONFIG_HYPERV!=n. Wrapping yet more > code with IS_ENABLED(CONFIG_HYPERV) eliminates a handful of conditional > branches, and makes it super obvious why the hooks *might* be valid. > > Cc: Vitaly Kuznetsov > Signed-off-by: Sean Christopherson > --- > arch/x86/include/asm/kvm-x86-ops.h | 2 ++ > arch/x86/include/asm/kvm_host.h | 12 ++++++++++++ > arch/x86/kvm/mmu/mmu.c | 12 ++++-------- > 3 files changed, 18 insertions(+), 8 deletions(-) > > diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h > index 26b628d84594..f482216bbdb8 100644 > --- a/arch/x86/include/asm/kvm-x86-ops.h > +++ b/arch/x86/include/asm/kvm-x86-ops.h > @@ -55,8 +55,10 @@ KVM_X86_OP(set_rflags) > KVM_X86_OP(get_if_flag) > KVM_X86_OP(flush_tlb_all) > KVM_X86_OP(flush_tlb_current) > +#if IS_ENABLED(CONFIG_HYPERV) > KVM_X86_OP_OPTIONAL(flush_remote_tlbs) > KVM_X86_OP_OPTIONAL(flush_remote_tlbs_range) > +#endif > KVM_X86_OP(flush_tlb_gva) > KVM_X86_OP(flush_tlb_guest) > KVM_X86_OP(vcpu_pre_run) > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 7c228ae05df0..f0d1ac871465 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -1614,9 +1614,11 @@ struct kvm_x86_ops { > > void (*flush_tlb_all)(struct kvm_vcpu *vcpu); > void (*flush_tlb_current)(struct kvm_vcpu *vcpu); > +#if IS_ENABLED(CONFIG_HYPERV) > int (*flush_remote_tlbs)(struct kvm *kvm); > int (*flush_remote_tlbs_range)(struct kvm *kvm, gfn_t gfn, > gfn_t nr_pages); > +#endif > > /* > * Flush any TLB entries associated with the given GVA. > @@ -1825,6 +1827,7 @@ static inline struct kvm *kvm_arch_alloc_vm(void) > #define __KVM_HAVE_ARCH_VM_FREE > void kvm_arch_free_vm(struct kvm *kvm); > > +#if IS_ENABLED(CONFIG_HYPERV) > #define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS > static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm) > { > @@ -1836,6 +1839,15 @@ static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm) > } > > #define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS_RANGE > +static inline int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, > + u64 nr_pages) > +{ > + if (!kvm_x86_ops.flush_remote_tlbs_range) > + return -EOPNOTSUPP; > + > + return static_call(kvm_x86_flush_remote_tlbs_range)(kvm, gfn, nr_pages); > +} > +#endif /* CONFIG_HYPERV */ > > #define kvm_arch_pmi_in_guest(vcpu) \ > ((vcpu) && (vcpu)->arch.handling_intr_from_guest) > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > index 5d3dc7119e57..0702f5234d69 100644 > --- a/arch/x86/kvm/mmu/mmu.c > +++ b/arch/x86/kvm/mmu/mmu.c > @@ -271,15 +271,11 @@ static inline unsigned long kvm_mmu_get_guest_pgd(struct kvm_vcpu *vcpu, > > static inline bool kvm_available_flush_remote_tlbs_range(void) > { > +#if IS_ENABLED(CONFIG_HYPERV) > return kvm_x86_ops.flush_remote_tlbs_range; > -} > - > -int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 nr_pages) > -{ > - if (!kvm_x86_ops.flush_remote_tlbs_range) > - return -EOPNOTSUPP; > - > - return static_call(kvm_x86_flush_remote_tlbs_range)(kvm, gfn, nr_pages); > +#else > + return false; > +#endif > } > > static gfn_t kvm_mmu_page_get_gfn(struct kvm_mmu_page *sp, int index); > > base-commit: 437bba5ad2bba00c2056c896753a32edf80860cc Makes sense, Reviewed-by: Vitaly Kuznetsov I can take it to my CONFIG_KVM_HYPERV series but it doesn't seem to intersect with it so I guess there's no need for that. -- Vitaly