Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754928Ab3GOTa1 (ORCPT ); Mon, 15 Jul 2013 15:30:27 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:27579 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753948Ab3GOTa0 (ORCPT ); Mon, 15 Jul 2013 15:30:26 -0400 X-Authority-Analysis: v=2.0 cv=KtrPKBqN c=1 sm=0 a=Sro2XwOs0tJUSHxCKfOySw==:17 a=Drc5e87SC40A:10 a=0OGBnBv_dtgA:10 a=5SG0PmZfjMsA:10 a=IkcTkHD0fZMA:10 a=meVymXHHAAAA:8 a=KGjhK52YXX0A:10 a=ringC-sgREwA:10 a=3N3TVzL0jjNlTnjXb_oA:9 a=QEXdDO2ut3YA:10 a=4UBfssCpKOcA:10 a=o7NNL0RPAFoA:10 a=5A4zu3kuagsA:10 a=SsdK35KI7XIA:10 a=Sro2XwOs0tJUSHxCKfOySw==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 67.255.60.225 Message-ID: <1373916620.17876.182.camel@gandalf.local.home> Subject: Re: nohz: Warn if the machine can not perform nohz_full From: Steven Rostedt To: Dave Jones Cc: Frederic Weisbecker , Linux Kernel Mailing List Date: Mon, 15 Jul 2013 15:30:20 -0400 In-Reply-To: <20130715185624.GB1706@redhat.com> References: <20130715170859.GA25570@redhat.com> <20130715171800.GD6442@somewhere> <20130715172423.GA27745@redhat.com> <20130715173848.GA1066@redhat.com> <1373914182.17876.165.camel@gandalf.local.home> <20130715185624.GB1706@redhat.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4-3 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 Content-Length: 1529 Lines: 38 On Mon, 2013-07-15 at 14:56 -0400, Dave Jones wrote: > On Mon, Jul 15, 2013 at 02:49:42PM -0400, Steven Rostedt wrote: > > Is a printk not enough for that purpose ? Tainting the kernel is kinda anti-social. > printk's don't usually get peoples attention. Taints and warnings do. If the hardware doesn't allow for nohz-full, and the only way to enable it is via kernel command line, how do you scream to the user that it isn't going to work. We could do a large banner saying: *************************************************************** *************************************************************** *************************************************************** *************************************************************** *** UNSTABLE TSC *** *** NO_HZ_FULL disabled *** *************************************************************** *************************************************************** *************************************************************** *************************************************************** And not do the warning. Maybe that will get peoples attentions? But then again, this could be lost in the boot up if the box prints a lot of data. -- Steve -- 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/