From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Kacur Subject: Re: [PATCH] make HWLAT_DETECTOR kernel config either disabled or a module, never builtin. Date: Tue, 22 Dec 2015 11:43:51 -0500 (EST) Message-ID: <486903158.1453998.1450802631110.JavaMail.zimbra@redhat.com> References: <20150923193340.0881074b@tor.valhalla.alchemy.lu> <20151211165240.GG6720@linutronix.de> <20151213113935.59cfd847@balder.valhalla.alchemy.lu> <20151222151117.GD27274@linutronix.de> <591364261.1447150.1450801543631.JavaMail.zimbra@redhat.com> <56797B8F.6090008@linutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: Joakim Hernberg , linux-rt-users@vger.kernel.org, Thomas Gleixner , Steven Rostedt , Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= To: Sebastian Andrzej Siewior Return-path: Received: from mx4-phx2.redhat.com ([209.132.183.25]:42560 "EHLO mx4-phx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754150AbbLVQoH (ORCPT ); Tue, 22 Dec 2015 11:44:07 -0500 In-Reply-To: <56797B8F.6090008@linutronix.de> Sender: linux-rt-users-owner@vger.kernel.org List-ID: ----- Original Message ----- > On 12/22/2015 05:25 PM, John Kacur wrote: > > The script can be made to handle it, that's not a big deal. I think the > > historical > > reason was worrying that people could be accidentally running a kernel with > > some really heavy weight debugging that would affect performance. However, > > let people > > hang themselves if they want. > > How can people hang themselves if they build it *into* the kernel? If I > understand *how* this can happen I will try to address it. However from > what I can see right now, nothing will happen if this module is built > into the kernel. > > > > > John > > > Sebastian All I mean is if you are accidentally running a debug kernel, you're going to get really bad performance, which is obvious. However, why are you arguing with me, I'm agreeing with and Clark is agreeing with you, let's make it possible for people to enable it now, and forget whatever historical reason stopped us from doing that before. John