From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756412AbbI1FjW (ORCPT ); Mon, 28 Sep 2015 01:39:22 -0400 Received: from mga03.intel.com ([134.134.136.65]:26611 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756297AbbI1FjT (ORCPT ); Mon, 28 Sep 2015 01:39:19 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,601,1437462000"; d="scan'208";a="814454370" From: Haozhong Zhang To: kvm@vger.kernel.org Cc: Gleb Natapov , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Joerg Roedel , Wanpeng Li , Xiao Guangrong , =?UTF-8?q?Mihai=20Don=C8=9Bu?= , Andy Lutomirski , Kai Huang , linux-kernel@vger.kernel.org, Haozhong Zhang Subject: [PATCH 11/12] KVM: VMX: Use a scaled host TSC for guest readings of MSR_IA32_TSC Date: Mon, 28 Sep 2015 13:38:10 +0800 Message-Id: <1443418691-24050-12-git-send-email-haozhong.zhang@intel.com> X-Mailer: git-send-email 2.4.8 In-Reply-To: <1443418691-24050-1-git-send-email-haozhong.zhang@intel.com> References: <1443418691-24050-1-git-send-email-haozhong.zhang@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch makes kvm-intel to return a scaled host TSC plus the TSC offset when handling guest readings to MSR_IA32_TSC. Signed-off-by: Haozhong Zhang --- arch/x86/kvm/vmx.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index e282eb8..d0a2928 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2245,15 +2245,15 @@ static void setup_msrs(struct vcpu_vmx *vmx) /* * reads and returns guest's timestamp counter "register" - * guest_tsc = host_tsc + tsc_offset -- 21.3 + * guest_tsc = (host_tsc * tsc multiplier) >> 48 + tsc_offset */ -static u64 guest_read_tsc(void) +static u64 guest_read_tsc(struct kvm_vcpu *vcpu) { u64 host_tsc, tsc_offset; host_tsc = rdtsc(); tsc_offset = vmcs_read64(TSC_OFFSET); - return host_tsc + tsc_offset; + return kvm_scale_tsc(vcpu, host_tsc) + tsc_offset; } /* @@ -2636,7 +2636,7 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) case MSR_EFER: return kvm_get_msr_common(vcpu, msr_info); case MSR_IA32_TSC: - msr_info->data = guest_read_tsc(); + msr_info->data = guest_read_tsc(vcpu); break; case MSR_IA32_SYSENTER_CS: msr_info->data = vmcs_read32(GUEST_SYSENTER_CS); -- 2.4.8