From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752989AbZJRIJb (ORCPT ); Sun, 18 Oct 2009 04:09:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751485AbZJRIJb (ORCPT ); Sun, 18 Oct 2009 04:09:31 -0400 Received: from mail-fx0-f218.google.com ([209.85.220.218]:35473 "EHLO mail-fx0-f218.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750901AbZJRIJ3 (ORCPT ); Sun, 18 Oct 2009 04:09:29 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:reply-to:user-agent:mime-version:to:subject :x-enigmail-version:content-type:content-transfer-encoding; b=l7xL14hYd+eZ/pua5oYPUoCh0Mgj0DpsaK6BRKopdts1tkL7QScG/uYGCKr87KAK2h qWMaM1YnYFK1g9wmcByE0mMR+KtybeSfV0VbX9SOAlPNTu7G8XqN4a/aWZRvR3X6NzHQ WP9vQNRK7zPDtf5PngRQlaIE0MJKxtBfyyDjM= Message-ID: <4ADACD3A.9020803@gmail.com> Date: Sun, 18 Oct 2009 10:09:30 +0200 From: Carmelo Amoroso Reply-To: carmelo73@gmail.com User-Agent: Thunderbird 2.0.0.23 (Macintosh/20090812) MIME-Version: 1.0 To: Linux Kernel Mailing List Subject: Fast LKM symbol resolution with SysV ELH hash table X-Enigmail-Version: 0.96.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I'm just sending this message to report about a work I've recently done to speed-up symbol resolution for modules by using a SysV ELF hash table (without relying upon binutils support). This work has been presented few days ago at the Embedded Linux Conference Europe. Patches are already publicly available for 2.6.23 kernel @STLinux git (http://git.stlinux.com/?p=stm/linux-sh4-2.6.23.y.git;a=summary) For 2.6.30 already ported but not yet available. Benchmarks have shown an average reduction of 96% in time spent for symbol resolution (that is 25x faster). All details can be found at http://tree.celinuxforum.org/CelfPubWiki/ELCEurope2009Presentations?action=AttachFile&do=view&target=C_AMOROSO_Fast_lkm_loader_ELC-E_2009.pdf I'm working to update them to mainline and post for review and discussion. We are also working right now to update this work too to use GNU hash instead of SysV ELF hash Carmelo