From patchwork Wed May 26 18:44:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilias Stamatis X-Patchwork-Id: 12282569 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D650CC47088 for ; Wed, 26 May 2021 18:47:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B6D23613D4 for ; Wed, 26 May 2021 18:47:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235702AbhEZSsi (ORCPT ); Wed, 26 May 2021 14:48:38 -0400 Received: from smtp-fw-9102.amazon.com ([207.171.184.29]:38611 "EHLO smtp-fw-9102.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233597AbhEZSsi (ORCPT ); Wed, 26 May 2021 14:48:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1622054827; x=1653590827; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version; bh=0tdpKVaxueVFi3JekWVHP4zb9TllD/q+HSeKSzNqIuM=; b=i+NIh4DYQav+pJECOwSlPBp9HYZGNiuxbhC+mO2YydlGGuzpaXIHu1c8 cDSklaldlpgUFiXxaoWs7M3hHBlsZe27eYyLVJSAF03Y9isG49OlYoM9a 7NudjU5WsJcgyzmWFuJWfE7Vl99rotUu0TUA4RiRFn0/2GIYcTsRSktLm U=; X-IronPort-AV: E=Sophos;i="5.82,331,1613433600"; d="scan'208";a="137030046" Received: from pdx4-co-svc-p1-lb2-vlan2.amazon.com (HELO email-inbound-relay-1d-38ae4ad2.us-east-1.amazon.com) ([10.25.36.210]) by smtp-border-fw-9102.sea19.amazon.com with ESMTP; 26 May 2021 18:47:05 +0000 Received: from EX13MTAUEE001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan2.iad.amazon.com [10.40.159.162]) by email-inbound-relay-1d-38ae4ad2.us-east-1.amazon.com (Postfix) with ESMTPS id 380F6A1D5C; Wed, 26 May 2021 18:47:04 +0000 (UTC) Received: from EX13D08UEE004.ant.amazon.com (10.43.62.182) by EX13MTAUEE001.ant.amazon.com (10.43.62.200) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Wed, 26 May 2021 18:46:45 +0000 Received: from EX13MTAUEA001.ant.amazon.com (10.43.61.82) by EX13D08UEE004.ant.amazon.com (10.43.62.182) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Wed, 26 May 2021 18:46:45 +0000 Received: from uae075a0dfd4c51.ant.amazon.com (10.106.82.24) by mail-relay.amazon.com (10.43.61.243) with Microsoft SMTP Server id 15.0.1497.18 via Frontend Transport; Wed, 26 May 2021 18:46:43 +0000 From: Ilias Stamatis To: , , CC: , , , , , , , , , Subject: [PATCH v4 08/11] KVM: X86: Move write_l1_tsc_offset() logic to common code and rename it Date: Wed, 26 May 2021 19:44:15 +0100 Message-ID: <20210526184418.28881-9-ilstam@amazon.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210526184418.28881-1-ilstam@amazon.com> References: <20210526184418.28881-1-ilstam@amazon.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org The write_l1_tsc_offset() callback has a misleading name. It does not set L1's TSC offset, it rather updates the current TSC offset which might be different if a nested guest is executing. Additionally, both the vmx and svm implementations use the same logic for calculating the current TSC before writing it to hardware. Rename the function and move the common logic to the caller. The vmx/svm specific code now merely sets the given offset to the corresponding hardware structure. Signed-off-by: Ilias Stamatis Reviewed-by: Maxim Levitsky --- arch/x86/include/asm/kvm-x86-ops.h | 2 +- arch/x86/include/asm/kvm_host.h | 3 +-- arch/x86/kvm/svm/svm.c | 21 ++++----------------- arch/x86/kvm/vmx/vmx.c | 23 +++-------------------- arch/x86/kvm/x86.c | 24 +++++++++++++++++++++--- 5 files changed, 30 insertions(+), 43 deletions(-) diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h index 2063616fba1c..029c9615378f 100644 --- a/arch/x86/include/asm/kvm-x86-ops.h +++ b/arch/x86/include/asm/kvm-x86-ops.h @@ -89,7 +89,7 @@ KVM_X86_OP(load_mmu_pgd) KVM_X86_OP_NULL(has_wbinvd_exit) KVM_X86_OP(get_l2_tsc_offset) KVM_X86_OP(get_l2_tsc_multiplier) -KVM_X86_OP(write_l1_tsc_offset) +KVM_X86_OP(write_tsc_offset) KVM_X86_OP(get_exit_info) KVM_X86_OP(check_intercept) KVM_X86_OP(handle_exit_irqoff) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index aaf756442ed1..f099277b993d 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1307,8 +1307,7 @@ struct kvm_x86_ops { u64 (*get_l2_tsc_offset)(struct kvm_vcpu *vcpu); u64 (*get_l2_tsc_multiplier)(struct kvm_vcpu *vcpu); - /* Returns actual tsc_offset set in active VMCS */ - u64 (*write_l1_tsc_offset)(struct kvm_vcpu *vcpu, u64 offset); + void (*write_tsc_offset)(struct kvm_vcpu *vcpu, u64 offset); /* * Retrieve somewhat arbitrary exit information. Intended to be used diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index ca70e46f9194..8dfb2513b72a 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1094,26 +1094,13 @@ static u64 svm_get_l2_tsc_multiplier(struct kvm_vcpu *vcpu) return kvm_default_tsc_scaling_ratio; } -static u64 svm_write_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 offset) +static void svm_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset) { struct vcpu_svm *svm = to_svm(vcpu); - u64 g_tsc_offset = 0; - - if (is_guest_mode(vcpu)) { - /* Write L1's TSC offset. */ - g_tsc_offset = svm->vmcb->control.tsc_offset - - svm->vmcb01.ptr->control.tsc_offset; - svm->vmcb01.ptr->control.tsc_offset = offset; - } - - trace_kvm_write_tsc_offset(vcpu->vcpu_id, - svm->vmcb->control.tsc_offset - g_tsc_offset, - offset); - - svm->vmcb->control.tsc_offset = offset + g_tsc_offset; + svm->vmcb01.ptr->control.tsc_offset = vcpu->arch.l1_tsc_offset; + svm->vmcb->control.tsc_offset = offset; vmcb_mark_dirty(svm->vmcb, VMCB_INTERCEPTS); - return svm->vmcb->control.tsc_offset; } /* Evaluate instruction intercepts that depend on guest CPUID features. */ @@ -4540,7 +4527,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { .get_l2_tsc_offset = svm_get_l2_tsc_offset, .get_l2_tsc_multiplier = svm_get_l2_tsc_multiplier, - .write_l1_tsc_offset = svm_write_l1_tsc_offset, + .write_tsc_offset = svm_write_tsc_offset, .load_mmu_pgd = svm_load_mmu_pgd, diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 1c83605eccc1..4b70431c2edd 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1808,26 +1808,9 @@ u64 vmx_get_l2_tsc_multiplier(struct kvm_vcpu *vcpu) return kvm_default_tsc_scaling_ratio; } -static u64 vmx_write_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 offset) +static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset) { - struct vmcs12 *vmcs12 = get_vmcs12(vcpu); - u64 g_tsc_offset = 0; - - /* - * We're here if L1 chose not to trap WRMSR to TSC. According - * to the spec, this should set L1's TSC; The offset that L1 - * set for L2 remains unchanged, and still needs to be added - * to the newly set TSC to get L2's TSC. - */ - if (is_guest_mode(vcpu) && - (vmcs12->cpu_based_vm_exec_control & CPU_BASED_USE_TSC_OFFSETTING)) - g_tsc_offset = vmcs12->tsc_offset; - - trace_kvm_write_tsc_offset(vcpu->vcpu_id, - vcpu->arch.tsc_offset - g_tsc_offset, - offset); - vmcs_write64(TSC_OFFSET, offset + g_tsc_offset); - return offset + g_tsc_offset; + vmcs_write64(TSC_OFFSET, offset); } /* @@ -7723,7 +7706,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { .get_l2_tsc_offset = vmx_get_l2_tsc_offset, .get_l2_tsc_multiplier = vmx_get_l2_tsc_multiplier, - .write_l1_tsc_offset = vmx_write_l1_tsc_offset, + .write_tsc_offset = vmx_write_tsc_offset, .load_mmu_pgd = vmx_load_mmu_pgd, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 705de0badc9e..801fa1e8e915 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2359,10 +2359,28 @@ u64 kvm_calc_nested_tsc_multiplier(u64 l1_multiplier, u64 l2_multiplier) } EXPORT_SYMBOL_GPL(kvm_calc_nested_tsc_multiplier); -static void kvm_vcpu_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset) +static void kvm_vcpu_write_tsc_offset(struct kvm_vcpu *vcpu, u64 l1_offset) { - vcpu->arch.l1_tsc_offset = offset; - vcpu->arch.tsc_offset = static_call(kvm_x86_write_l1_tsc_offset)(vcpu, offset); + trace_kvm_write_tsc_offset(vcpu->vcpu_id, + vcpu->arch.l1_tsc_offset, + l1_offset); + + vcpu->arch.l1_tsc_offset = l1_offset; + + /* + * If we are here because L1 chose not to trap WRMSR to TSC then + * according to the spec this should set L1's TSC (as opposed to + * setting L1's offset for L2). + */ + if (is_guest_mode(vcpu)) + vcpu->arch.tsc_offset = kvm_calc_nested_tsc_offset( + l1_offset, + static_call(kvm_x86_get_l2_tsc_offset)(vcpu), + static_call(kvm_x86_get_l2_tsc_multiplier)(vcpu)); + else + vcpu->arch.tsc_offset = l1_offset; + + static_call(kvm_x86_write_tsc_offset)(vcpu, vcpu->arch.tsc_offset); } static inline bool kvm_check_tsc_unstable(void)