Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755317Ab0DISLP (ORCPT ); Fri, 9 Apr 2010 14:11:15 -0400 Received: from bamako.nerim.net ([62.4.17.28]:49592 "EHLO bamako.nerim.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755206Ab0DISLO convert rfc822-to-8bit (ORCPT ); Fri, 9 Apr 2010 14:11:14 -0400 Date: Fri, 9 Apr 2010 20:11:10 +0200 From: Jean Delvare To: Jiri Kosina Cc: =?UTF-8?B?w4lyaWM=?= Piel , Marcin Derlukiewicz , linux-kernel@vger.kernel.org, lm-sensors@lm-sensors.org, Pavel Machek , Andrew Morton Subject: Re: [lm-sensors] [PATCH] lis3lv02d: provide means to disable polled input interface Message-ID: <20100409201110.5d75a24e@hyperion.delvare> In-Reply-To: References: <4BBF2BD1.5050107@tremplin-utc.net> X-Mailer: Claws Mail 3.5.0 (GTK+ 2.14.4; i586-suse-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1663 Lines: 36 On Fri, 9 Apr 2010 15:32:59 +0200 (CEST), Jiri Kosina wrote: > On Fri, 9 Apr 2010, Éric Piel wrote: > > > > This is reported to create 20% CPU usage increase (and proportionaly higher > > > power consumption) just for the ipolldevd kernel thread (which is used > > > to read the sensor). > > > > > > As most users probably only use the freefall functionality of the driver > > > and not the joystick interface, provide means for disabling the registration > > > of joystick device altogether via module parameter. > > > (I'd rather make it default to 0, but this will break backwards compatibility). > > Are you saying there is a 20% CPU usage even when the joystick interface > > is not open? This should not happen (and this is not happening on my > > laptop). The polling should happen only when a userspace app opens the > > joystick interface (like running neverball). > > > > So I'd tend to think it's more due to a misconfiguration of the system > > (like xserver using the joystick interface as a pointer device) or it's > > a bug in the way we set up the polling. Could you investigate and let me > > know? > > Marcin originally reported this to me. > > Marcin, could you please check 'lsof' output to see whether the joystick > interface has been open by some application? I would randomly blame hal. It keeps my IR remote control device opened all the time and I have no idea why. -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/