From owner-svn-src-head@FreeBSD.ORG Thu Oct 16 21:10:25 2008 Return-Path: Delivered-To: svn-src-head@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B4EE61065687; Thu, 16 Oct 2008 21:10:25 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from harmony.bsdimp.com (bsdimp.com [199.45.160.85]) by mx1.freebsd.org (Postfix) with ESMTP id 674C88FC0A; Thu, 16 Oct 2008 21:10:25 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from localhost (localhost [127.0.0.1]) by harmony.bsdimp.com (8.14.2/8.14.1) with ESMTP id m9GL9AMI017946; Thu, 16 Oct 2008 15:09:10 -0600 (MDT) (envelope-from imp@bsdimp.com) Date: Thu, 16 Oct 2008 15:10:12 -0600 (MDT) Message-Id: <20081016.151012.1933498518.imp@bsdimp.com> To: scottl@samsco.org From: "M. Warner Losh" In-Reply-To: <48F5053D.7070705@samsco.org> References: <200810142028.m9EKShoL015514@svn.freebsd.org> <48F5053D.7070705@samsco.org> X-Mailer: Mew version 5.2 on Emacs 21.3 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: svn-src-head@FreeBSD.org, marius@FreeBSD.org, src-committers@FreeBSD.org, svn-src-all@FreeBSD.org Subject: Re: svn commit: r183896 - head/sys/dev/bge X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 16 Oct 2008 21:10:25 -0000 In message: <48F5053D.7070705@samsco.org> Scott Long writes: : Marius Strobl wrote: : > Author: marius : > Date: Tue Oct 14 20:28:42 2008 : > New Revision: 183896 : > URL: http://svn.freebsd.org/changeset/base/183896 : > : > Log: : > Use bus_{read,write}_4(9) instead of bus_space_{read,write}_4(9) : > in order to get rid of the bus space handle and tag in the softc. : > : : Has anyone looked at the generated code from this interface switch and : compared it what was getting generated previously? Way back when, : including made bus_space_read|write_4() compile : into a direct memory access on machines that supported it. The dubious : removal of bus_memio.h and bus_pio.h took away that benefit, and I'm : afraid that it's only getting worse now. Bus writes to card memory are : still very important to high-performance devices and shouldn't be : pessimized in the name of simpler-looking C code. I've looked a little. With changes similar to this change, the generated code does look better because there's less stack traffic, but it still isn't a direct write to memory without a function call... Warner