From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Tosatti Subject: Re: [patch 2/3] KVM: MMU: skip global pgtables on sync due to cr3 switch Date: Fri, 31 Oct 2008 17:50:45 -0200 Message-ID: <20081031195045.GE21772@dmt.cnet> References: <20081025223111.498934405@localhost.localdomain> <20081025223243.863908646@localhost.localdomain> <49045426.1080807@redhat.com> <20081031193603.GC21772@dmt.cnet> <490B5FF6.4040806@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 mx2.redhat.com ([66.187.237.31]:42554 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750842AbYJaTv4 (ORCPT ); Fri, 31 Oct 2008 15:51:56 -0400 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id m9VJpueX028459 for ; Fri, 31 Oct 2008 15:51:56 -0400 Content-Disposition: inline In-Reply-To: <490B5FF6.4040806@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Fri, Oct 31, 2008 at 09:43:50PM +0200, Avi Kivity wrote: > Marcelo Tosatti wrote: >>> But a more accurate approach is to keep a count of non-global >>> present mappings, and to activate the global logic when this count >>> is nonzero. >>> >> >> I don't think the overhead it adds is significant for the added >> complexity? > > Not sure what you're asking exactly (-ENOPARSE). I don't think it's > worthwhile to account for !global -> global transitions. Was referring to "active the global logic when this count is nonzero" (ie don't see the point of keeping non-global count).