From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757457AbWK0Iud (ORCPT ); Mon, 27 Nov 2006 03:50:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757465AbWK0Iud (ORCPT ); Mon, 27 Nov 2006 03:50:33 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:43473 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S1757457AbWK0Iuc (ORCPT ); Mon, 27 Nov 2006 03:50:32 -0500 Subject: Re: Weird wasting of time between ioctl() and ioctl dispatcher From: Arjan van de Ven To: "Cestonaro, Thilo (external)" Cc: linux-kernel@vger.kernel.org In-Reply-To: References: Content-Type: text/plain Organization: Intel International BV Date: Mon, 27 Nov 2006 09:50:29 +0100 Message-Id: <1164617429.3276.18.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.8.1.1 (2.8.1.1-3.fc6) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2006-11-27 at 09:24 +0100, Cestonaro, Thilo (external) wrote: > Hey, > > I'm a developer for Fujitsu Siemens Computers, working on a program which has it's own kernel modules and userland components. > Now cause the program should be released we have done some testing and during this testphase a wierd wasting of time occured > during the call of the ioctl() in the userland component and the actuall entering of the dispatcher function in the module. > It takes 3 min. until the call at last enters my dispatcher. (Debugging output with printf on line before ioctl() and printk as first line in the > dispatch function points that out). The dispatch function is the ioctl part of the fileoperations struct which defines the module stuff. > > The kernel I'm running is the 2.6.16.21-0.8-default of SLED10 (32Bit), but installed on a 64Bit machine. > Can anyone point me to, where I can have a look where the waste of time comes from? > > The ioctl itself works fine afterwards, but the whole process is time-critical so the 3 min. do hurt :(. Hi, unfortunately you did not post the source code of at least your kernel driver, nor did you provide an URL to the source, so it's really hard for us to help you. Would you mind correcting this oversight? Greetings, Arjan van de Ven -- if you want to mail me at work (you don't), use arjan (at) linux.intel.com Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org