From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: [PATCH] KVM: MMU: simplify folding of dirty bit into accessed_dirty Date: Mon, 7 Jan 2013 20:31:50 -0200 Message-ID: <20130107223150.GC1139@amt.cnet> References: <20121227124458.GP17584@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kvm@vger.kernel.org To: Gleb Natapov Return-path: Received: from mx1.redhat.com ([209.132.183.28]:50375 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756027Ab3AGXC7 (ORCPT ); Mon, 7 Jan 2013 18:02:59 -0500 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r07N2x0W027741 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 7 Jan 2013 18:02:59 -0500 Content-Disposition: inline In-Reply-To: <20121227124458.GP17584@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, Dec 27, 2012 at 02:44:58PM +0200, Gleb Natapov wrote: > MMU code tries to avoid if()s HW is not able to predict reliably by using > bitwise operation to streamline code execution, but in case of a dirty bit > folding this gives us nothing since write_fault is checked right before > the folding code. Lets just piggyback onto the if() to make code more clear. > > Signed-off-by: Gleb Natapov Applied, thanks.