From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756845AbZBYSNK (ORCPT ); Wed, 25 Feb 2009 13:13:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752245AbZBYSM4 (ORCPT ); Wed, 25 Feb 2009 13:12:56 -0500 Received: from ug-out-1314.google.com ([66.249.92.169]:22455 "EHLO ug-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751513AbZBYSMz (ORCPT ); Wed, 25 Feb 2009 13:12:55 -0500 MIME-Version: 1.0 In-Reply-To: <200902251733.57069.rusty@rustcorp.com.au> References: <1234722028-8110-1-git-send-email-andr345@gmail.com> <200902202202.13994.rusty@rustcorp.com.au> <200902251733.57069.rusty@rustcorp.com.au> Date: Wed, 25 Feb 2009 19:12:52 +0100 Message-ID: Subject: Re: [RFC PATCH 0/6] module, kbuild: Faster boot with custom kernel. From: Kay Sievers To: Rusty Russell Cc: Andreas Robinson , sam@ravnborg.org, linux-kernel@vger.kernel.org, Jon Masters , heiko.carstens@de.ibm.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 25, 2009 at 08:03, Rusty Russell wrote: > On Tuesday 24 February 2009 03:12:28 Kay Sievers wrote: >> Rusty, >> are you taking care, that this patch gets merged somewhere, and shows >> up in -next? > > Yep, already done. Nice. Thanks! >> I still get a ~10% improvement without the mutex, and traces show some >> parallelism from different modprobe processes. Any idea how to safely >> minimize the time we need to hold it? > > OK, let's do that then. > > > > Here's a backported version which you should be able to simply apply; it'll > be good to check that we still win... It's a little bit faster, and the traces show a bit less serialization and more overlapping code execution. The difference is very small though, and hard to notice -- loading of all the 39 modules triggered by a udev coldplug run finishes after 0.23 seconds. After calling init, the last of these modules goes "live" after 0.26 seconds. Most of the time the modules need is spent in simplify_symbols(). Thanks, Kay