From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754944Ab3L0WxK (ORCPT ); Fri, 27 Dec 2013 17:53:10 -0500 Received: from dan.rpsys.net ([93.97.175.187]:52890 "EHLO dan.rpsys.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754848Ab3L0WxI (ORCPT ); Fri, 27 Dec 2013 17:53:08 -0500 X-Greylist: delayed 438 seconds by postgrey-1.27 at vger.kernel.org; Fri, 27 Dec 2013 17:53:07 EST Message-ID: <1388184301.11527.29.camel@ted> Subject: Re: [PATCH] Add the LED burst trigger From: Richard Purdie To: One Thousand Gnomes Cc: Pavel Machek , Joe Xue , "cooloney@gmail.com" , "rob@landley.net" , "milo.kim@ti.com" , "linux-leds@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" Date: Fri, 27 Dec 2013 22:45:01 +0000 In-Reply-To: <20131227181349.475abe88@alan.etchedpixels.co.uk> References: <1387895407-28031-1-git-send-email-lgxue@hotmail.com> <20131225230935.GB13593@amd.pavel.ucw.cz> <20131227115746.4cbd9523@alan.etchedpixels.co.uk> <20131227125725.GA21506@amd.pavel.ucw.cz> <20131227141826.3fe406e4@alan.etchedpixels.co.uk> <20131227152354.GA24152@amd.pavel.ucw.cz> <20131227181349.475abe88@alan.etchedpixels.co.uk> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.8.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2013-12-27 at 18:13 +0000, One Thousand Gnomes wrote: > > Well, this one will be really smaller. And yes, it will make some > > memory non-swappable, but I believe with triggers and infrastructure > > for N900 (and similar) it will be worth it. > > Ah yes thats such a major proportion of platforms > > > Plus, it will actually save CPU cycles, and thus significant power. > > All of which will be totally wiped out if you bump all the millions of > x86 server boxes in the world up by one page of kernel space and cause a > few disk I/Os FWIW the LED subsystem was designed to take advantage of kernel modules. If you don't use a given trigger, it needn't be in memory, loaded or even built at all. If something changed there which made that not possible, that would be rather sad. I agree with you that we shouldn't bump the kernel size unnecessarily but I don't think triggers should do so. I actually think the kernel could do with going on a diet and at least made so you can untangle more of the pieces you don't want/need. Cheers, Richard