From mboxrd@z Thu Jan 1 00:00:00 1970 From: Knut Petersen Subject: Re: Fw: framebuffer blitting performance loss 2.6.12 -> 2.6.13-rc3 Date: Fri, 29 Jul 2005 22:10:23 +0200 Message-ID: <42EA8D2F.9040801@t-online.de> References: <20050715033912.1cd9b6c3.akpm@osdl.org> <200507221158.23454.adaplas@gmail.com> <20050729001735.5934622f.akpm@osdl.org> <42EA430C.2010405@t-online.de> <42EA4E6A.70907@gmail.com> Reply-To: linux-fbdev-devel@lists.sourceforge.net Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1DybAB-0000nu-33 for linux-fbdev-devel@lists.sourceforge.net; Fri, 29 Jul 2005 13:08:59 -0700 Received: from mailout09.sul.t-online.com ([194.25.134.84]) by mail.sourceforge.net with esmtp (Exim 4.44) id 1DybAA-0004tq-Lv for linux-fbdev-devel@lists.sourceforge.net; Fri, 29 Jul 2005 13:08:59 -0700 In-Reply-To: <42EA4E6A.70907@gmail.com> Sender: linux-fbdev-devel-admin@lists.sourceforge.net Errors-To: linux-fbdev-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: List-Post: List-Help: List-Subscribe: , List-Archive: Content-Type: text/plain; charset="iso-8859-1"; format="flowed" To: linux-fbdev-devel@lists.sourceforge.net Hi Tony, > > Thank you for your persistence. I think I know the culprit. Someone > insisted on using memcpy in fb_pad_aligned_buffer(). I have already > fixed this before, but apparently, the memcpy was brought back. Try > the attached patch and let me know. > > Tony Replacing memcpy() with this inline code helps. Performance is slightly=20 slower than it was in 2.6.12, but this is hardly measurable and could be caused by=20 other changes in the kernel. The most affected test, (test 3, cyblafb, ypan) now is about 7ms slower=20 than it was in 2.6.12. Without your patch the performance penalty was 202ms! Yes, please send the patch to Linus asap, it=B4s a must for 2.6.13. Someone should look at memcpy ;-) cu, Knut ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_id=3D7477&alloc_id=3D16492&op=3Dclic= k