From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Tue, 23 Dec 2008 14:39:16 +0000 (GMT) Received: from localhost.localdomain ([127.0.0.1]:7083 "EHLO mail.linux-mips.net") by ftp.linux-mips.org with ESMTP id S24207611AbYLWOjM (ORCPT ); Tue, 23 Dec 2008 14:39:12 +0000 Received: from fluff.linux-mips.net (localhost.localdomain [127.0.0.1]) by mail.linux-mips.net (8.14.2/8.13.1) with ESMTP id mBNEdBIW006486; Tue, 23 Dec 2008 15:39:11 +0100 Received: (from ralf@localhost) by fluff.linux-mips.net (8.14.2/8.14.2/Submit) id mBNEd9oD006485; Tue, 23 Dec 2008 15:39:09 +0100 Date: Tue, 23 Dec 2008 15:39:09 +0100 From: Ralf Baechle To: Manuel Lauss Cc: Linux-MIPS Subject: Re: [PATCH 2/2] Alchemy: provide cpu feature overrides. Message-ID: <20081223143909.GD5981@linux-mips.org> References: <1229973668-18182-1-git-send-email-mano@roarinelk.homelinux.net> <1229973668-18182-2-git-send-email-mano@roarinelk.homelinux.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1229973668-18182-2-git-send-email-mano@roarinelk.homelinux.net> User-Agent: Mutt/1.5.18 (2008-05-17) Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 21657 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: ralf@linux-mips.org Precedence: bulk X-list: linux-mips On Mon, Dec 22, 2008 at 08:21:08PM +0100, Manuel Lauss wrote: > Add cpu feature override constants for Alchemy. > > Code generated for Alchemy does not use all MIPS32r1 features. Add cpu > feature overrides tailored for Alchemy chips and help GCC create better > code. As a nice sideeffect the size of the resulting kernel is reduced > by a few kilobytes (~200kB for a non-modular db1200 devboard build). The enormous size difference is probably 99% due to atomic and bitops which exist in LL/SC and non-LL/SC versions and without the header gcc will expand the inline function each time. That will hurt, also performance. Also the big size difference suggests that we may want to outline some or all of these functions. Ralf