From patchwork Wed May 26 18:44:07 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ilias Stamatis X-Patchwork-Id: 12282553 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=-14.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, 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 9572CC47088 for ; Wed, 26 May 2021 18:45:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 72C426102A for ; Wed, 26 May 2021 18:45:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235596AbhEZSrD (ORCPT ); Wed, 26 May 2021 14:47:03 -0400 Received: from smtp-fw-4101.amazon.com ([72.21.198.25]:29632 "EHLO smtp-fw-4101.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232964AbhEZSrC (ORCPT ); Wed, 26 May 2021 14:47:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1622054731; x=1653590731; h=from:to:cc:subject:date:message-id:mime-version; bh=VjHKWOUbi6AsBQGrFu6LwnjmojKTzUmMLMOu456RPpE=; b=ExDzAdAwX2JQgAmJu5JalElie5QEiO0s+vBVDazarZ5u8NeFf+6C7iNU 61eRybBwe8Ul0nE8Kh9xnRWZMaO2BWITLDkAc+YfL/ZvZxPpSJGYYw60K 3+JE6tX6qTiP/nkUelnvteY6wRaGczd+fMXKZlOXktFnWfep6FfZ9g9G1 U=; X-IronPort-AV: E=Sophos;i="5.82,331,1613433600"; d="scan'208";a="110382147" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-2c-2225282c.us-west-2.amazon.com) ([10.43.8.6]) by smtp-border-fw-4101.iad4.amazon.com with ESMTP; 26 May 2021 18:45:22 +0000 Received: from EX13MTAUEE002.ant.amazon.com (pdx1-ws-svc-p6-lb9-vlan3.pdx.amazon.com [10.236.137.198]) by email-inbound-relay-2c-2225282c.us-west-2.amazon.com (Postfix) with ESMTPS id 97ABFA18BD; Wed, 26 May 2021 18:45:21 +0000 (UTC) Received: from EX13D08UEE003.ant.amazon.com (10.43.62.118) by EX13MTAUEE002.ant.amazon.com (10.43.62.24) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Wed, 26 May 2021 18:45:21 +0000 Received: from EX13MTAUEA001.ant.amazon.com (10.43.61.82) by EX13D08UEE003.ant.amazon.com (10.43.62.118) with Microsoft SMTP Server (TLS) id 15.0.1497.18; Wed, 26 May 2021 18:45:21 +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 18:45:19 +0000 From: Ilias Stamatis To: , , CC: , , , , , , , , , Subject: [PATCH v4 00/11] KVM: Implement nested TSC scaling Date: Wed, 26 May 2021 19:44:07 +0100 Message-ID: <20210526184418.28881-1-ilstam@amazon.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org KVM currently supports hardware-assisted TSC scaling but only for L1; the feature is not exposed to nested guests. This patch series adds support for nested TSC scaling and allows both L1 and L2 to be scaled with different scaling factors. That is achieved by "merging" the 01 and 02 values together. Most of the logic in this series is implemented in common code (by doing the necessary restructurings), however the patches add support for VMX only. Adding support for SVM should be easy at this point and Maxim Levitsky has volunteered to do this (thanks!). Changelog: Only patch 9 needs reviewing at this point, but I am re-sending the whole series as I also applied nitpicks suggested to some of the other pathces. v4: - Added vendor callbacks for writing the TSC multiplier - Moved the VMCS multiplier writes from the VMCS load path to common code that only gets called on TSC ratio changes - Merged together patches 10 and 11 of v3 - Applied all nitpick-feedback of the previous versions v3: - Applied Sean's feedback - Refactored patches 7 to 10 v2: - Applied all of Maxim's feedback - Added a mul_s64_u64_shr function in math64.h - Added a separate kvm_scale_tsc_l1 function instead of passing an argument to kvm_scale_tsc - Implemented the 02 fields calculations in common code - Moved all of write_l1_tsc_offset's logic to common code - Added a check for whether the TSC is stable in patch 10 - Used a random L1 factor and a negative offset in patch 10 Ilias Stamatis (11): math64.h: Add mul_s64_u64_shr() KVM: X86: Store L1's TSC scaling ratio in 'struct kvm_vcpu_arch' KVM: X86: Rename kvm_compute_tsc_offset() to kvm_compute_l1_tsc_offset() KVM: X86: Add a ratio parameter to kvm_scale_tsc() KVM: nVMX: Add a TSC multiplier field in VMCS12 KVM: X86: Add functions for retrieving L2 TSC fields from common code KVM: X86: Add functions that calculate the nested TSC fields KVM: X86: Move write_l1_tsc_offset() logic to common code and rename it KVM: X86: Add vendor callbacks for writing the TSC multiplier KVM: nVMX: Enable nested TSC scaling KVM: selftests: x86: Add vmx_nested_tsc_scaling_test arch/x86/include/asm/kvm-x86-ops.h | 5 +- arch/x86/include/asm/kvm_host.h | 15 +- arch/x86/kvm/svm/svm.c | 35 ++- arch/x86/kvm/vmx/nested.c | 33 ++- arch/x86/kvm/vmx/vmcs12.c | 1 + arch/x86/kvm/vmx/vmcs12.h | 4 +- arch/x86/kvm/vmx/vmx.c | 55 ++-- arch/x86/kvm/vmx/vmx.h | 11 +- arch/x86/kvm/x86.c | 114 +++++++-- include/linux/math64.h | 19 ++ tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../kvm/x86_64/vmx_nested_tsc_scaling_test.c | 242 ++++++++++++++++++ 13 files changed, 451 insertions(+), 85 deletions(-) create mode 100644 tools/testing/selftests/kvm/x86_64/vmx_nested_tsc_scaling_test.c