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 X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=unavailable 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 C5ECAC31E4B for ; Fri, 14 Jun 2019 16:25:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A961B21841 for ; Fri, 14 Jun 2019 16:25:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726213AbfFNQZm (ORCPT ); Fri, 14 Jun 2019 12:25:42 -0400 Received: from mga04.intel.com ([192.55.52.120]:18718 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725852AbfFNQZk (ORCPT ); Fri, 14 Jun 2019 12:25:40 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Jun 2019 09:25:39 -0700 X-ExtLoop1: 1 Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.36]) by fmsmga005.fm.intel.com with ESMTP; 14 Jun 2019 09:25:39 -0700 Date: Fri, 14 Jun 2019 09:25:39 -0700 From: Sean Christopherson To: Paolo Bonzini Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, vkuznets@redhat.com Subject: Re: [PATCH 21/43] KVM: nVMX: Don't reread VMCS-agnostic state when switching VMCS Message-ID: <20190614162532.GG12191@linux.intel.com> References: <1560445409-17363-1-git-send-email-pbonzini@redhat.com> <1560445409-17363-22-git-send-email-pbonzini@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1560445409-17363-22-git-send-email-pbonzini@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 13, 2019 at 07:03:07PM +0200, Paolo Bonzini wrote: > From: Sean Christopherson > > When switching between vmcs01 and vmcs02, there is no need to update > state tracking for values that aren't tied to any particular VMCS as > the per-vCPU values are already up-to-date (vmx_switch_vmcs() can only > be called when the vCPU is loaded). > > Avoiding the update eliminates a RDMSR, and potentially a RDPKRU and > posted-interrupt updated (cmpxchg64() and more). Another typo, s/updated/update. > > Signed-off-by: Sean Christopherson > Signed-off-by: Paolo Bonzini > ---