From patchwork Wed Apr 10 09:55:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 10893553 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 446F7139A for ; Wed, 10 Apr 2019 09:55:34 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2F2222899E for ; Wed, 10 Apr 2019 09:55:34 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2377A28A40; Wed, 10 Apr 2019 09:55:34 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BBD712899E for ; Wed, 10 Apr 2019 09:55:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730288AbfDJJzc (ORCPT ); Wed, 10 Apr 2019 05:55:32 -0400 Received: from mail-wm1-f68.google.com ([209.85.128.68]:35952 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730273AbfDJJza (ORCPT ); Wed, 10 Apr 2019 05:55:30 -0400 Received: by mail-wm1-f68.google.com with SMTP id h18so1871765wml.1; Wed, 10 Apr 2019 02:55:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:subject:date:message-id; bh=7i5SlzB6pHh66J0GYb7kkJCIFl3+YonnZRmzOlo+++w=; b=ti2Me5wxoKo25HKKQwB+dF65zRsFaErnPpgfV8rresaxjyK3P1Q06Dv49Fu4NEk90J VGvAamRYEIuycfzyKC/YgmAc/zXBsLcLUGeo6L6qSH4AdOdwGyxQrkrKj/WbR8Wx7E7g o5BakOOj6hPlohLdT1/cphUIb77KnUpj5ihBQvTt64FZEuoC0LQwoUPfGs9b4zXx24jI 2kFu88kwRKyHFXb6ShzHWuO1KquBOWNNonHt/Ae4rrEjbRsnNtbO9VbwlvAo9mS7L+aH KowL9K6mmjFdyO6CefDOniHogyX6szoO/czKh1gWoGahoonV9JmPk21zcOvhqsnreyrn sW9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:subject:date:message-id; bh=7i5SlzB6pHh66J0GYb7kkJCIFl3+YonnZRmzOlo+++w=; b=meengXjU6cGLSnVo0wN7oxwyNAlGvxCDOhnqOI+N2Ut3E+gUVdXgIO7y9S9H4+HGwW 7HjUDsEIwA/uC+JCF8M/sauiCrqkzLWhBB/V5sT8i6x45ZHCw5x0B4TwnCRIyAYpH1cb ToBV9CpfSPqrEtVKypExXHVvk39/d/yNPzSUnKLKGOsdMCRI1OyN/pLQnpUWjAKoEGrd x0FtLfIekRxWaW2b495x5bXBU7ffPPvd2/UQ6q/E+dWoc0q9k9LyjUZIU8urCdM9l1Yr lc+WaJJXzc3QIxKM4tquORURjrQyFgAPlnxdkGwWjFL1Vf9ZjjvzknpPp1QjbbX+VdRK z7qQ== X-Gm-Message-State: APjAAAUDpFj4SpeiP0m5oM5MaMcwWEiGif78OMZmybcG2nUkWrrXkScm lulW/CFrXcXslgKznk+NqRjULOAU X-Google-Smtp-Source: APXvYqxbTEigNqveRBFvSAsWST9oBqt2HCxb37Br90t7NTuEwc7Ve7JXRYKOtV7RHvY6k+ANRLAm6w== X-Received: by 2002:a7b:ce84:: with SMTP id q4mr2220645wmj.41.1554890127964; Wed, 10 Apr 2019 02:55:27 -0700 (PDT) Received: from 640k.lan ([93.56.166.5]) by smtp.gmail.com with ESMTPSA id x192sm2293103wmf.48.2019.04.10.02.55.27 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 10 Apr 2019 02:55:27 -0700 (PDT) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: [PATCH] KVM: x86: optimize check for valid PAT value Date: Wed, 10 Apr 2019 11:55:26 +0200 Message-Id: <1554890126-347-1-git-send-email-pbonzini@redhat.com> X-Mailer: git-send-email 1.8.3.1 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This check will soon be done on every nested vmentry and vmexit, "parallelize" it using bitwise operations. Signed-off-by: Paolo Bonzini Reviewed-by: Sean Christopherson Reviewed-by: Krish Sadhukhan --- arch/x86/kvm/mtrr.c | 10 +--------- arch/x86/kvm/vmx/vmx.c | 2 +- arch/x86/kvm/x86.h | 8 ++++++++ 3 files changed, 10 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c index e9ea2d45ae66..9f72cc427158 100644 --- a/arch/x86/kvm/mtrr.c +++ b/arch/x86/kvm/mtrr.c @@ -48,11 +48,6 @@ static bool msr_mtrr_valid(unsigned msr) return false; } -static bool valid_pat_type(unsigned t) -{ - return t < 8 && (1 << t) & 0xf3; /* 0, 1, 4, 5, 6, 7 */ -} - static bool valid_mtrr_type(unsigned t) { return t < 8 && (1 << t) & 0x73; /* 0, 1, 4, 5, 6 */ @@ -67,10 +62,7 @@ bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data) return false; if (msr == MSR_IA32_CR_PAT) { - for (i = 0; i < 8; i++) - if (!valid_pat_type((data >> (i * 8)) & 0xff)) - return false; - return true; + return kvm_pat_valid(data); } else if (msr == MSR_MTRRdefType) { if (data & ~0xcff) return false; diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index b6c533afbf27..b74679732cfc 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1891,7 +1891,7 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) break; case MSR_IA32_CR_PAT: if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT) { - if (!kvm_mtrr_valid(vcpu, MSR_IA32_CR_PAT, data)) + if (!kvm_pat_valid(data)) return 1; vmcs_write64(GUEST_IA32_PAT, data); vcpu->arch.pat = data; diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 28406aa1136d..7bc7ac9d2a44 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -347,4 +347,12 @@ static inline void kvm_after_interrupt(struct kvm_vcpu *vcpu) __this_cpu_write(current_vcpu, NULL); } +static inline bool kvm_pat_valid(u64 data) +{ + if (data & 0xF8F8F8F8F8F8F8F8) + return false; + /* 0, 1, 4, 5, 6, 7 are valid values. */ + return (data | ((data & 0x0202020202020202) << 1)) == data; +} + #endif