From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:45299) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TSscw-0007BJ-9M for qemu-devel@nongnu.org; Mon, 29 Oct 2012 12:55:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TSscl-0007OU-7H for qemu-devel@nongnu.org; Mon, 29 Oct 2012 12:55:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:21089) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TSsIV-0001rJ-Sd for qemu-devel@nongnu.org; Mon, 29 Oct 2012 12:34:44 -0400 Message-ID: <508EB01D.5010608@redhat.com> Date: Mon, 29 Oct 2012 18:34:37 +0200 From: Avi Kivity MIME-Version: 1.0 References: <20121027041159.GA20153@zapo> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC] Memory API and fine grained Memory Regions List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: John Williams Cc: Peter Maydell , "Edgar E. Iglesias" , John Williams , "qemu-devel@nongnu.org Developers" , Peter Crosthwaite On 10/29/2012 01:37 AM, John Williams wrote: >> IMO, an mr per reg would just add a massive overhead for no win. > > I tend to agree with Edgar here - QEMU has a careful line to walk between being an emulator and an RTL simulator. > > Any WAG on the runtime overhead of a mem region per register vs a switch-based decodes in read/write handlers? > Actually a region-per-register can be faster, since the subpage logic will dispatch the access directly to the handler, instead of going first to the device handler, then following the switch. -- error compiling committee.c: too many arguments to function