From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: [PATCH 0/2] Optimize ds/es reload Date: Wed, 16 May 2012 16:04:03 -0300 Message-ID: <20120516190403.GA25004@amt.cnet> References: <1336928004-6366-1-git-send-email-avi@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm@vger.kernel.org To: Avi Kivity Return-path: Received: from mx1.redhat.com ([209.132.183.28]:58594 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760471Ab2EPTIx (ORCPT ); Wed, 16 May 2012 15:08:53 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q4GJ8qRk019459 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 16 May 2012 15:08:52 -0400 Content-Disposition: inline In-Reply-To: <1336928004-6366-1-git-send-email-avi@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Sun, May 13, 2012 at 07:53:22PM +0300, Avi Kivity wrote: > The lightweight exit path needlessly reloads %ds and %es (and clobbers the > user supplied values as well, a minor ABI bug). This patchset fixes the bug > and moves the reload to the heavyweight exit path (potentially skipping it > completely on x86_64), reducing the vmexit cost by about 70 cycles. > > Avi Kivity (2): > KVM: VMX: Fix %ds/%es clobber > KVM: VMX: Optimize %ds, %es reload > > arch/x86/kvm/vmx.c | 32 +++++++++++++++++++++++++++++++- > 1 file changed, 31 insertions(+), 1 deletion(-) Applied, thanks.