Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753261AbaBFSdx (ORCPT ); Thu, 6 Feb 2014 13:33:53 -0500 Received: from mail1.windriver.com ([147.11.146.13]:41456 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751403AbaBFSdw (ORCPT ); Thu, 6 Feb 2014 13:33:52 -0500 Message-ID: <52F3D583.9070208@windriver.com> Date: Thu, 6 Feb 2014 13:33:39 -0500 From: Paul Gortmaker User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Frederic Weisbecker , "Paul E. McKenney" CC: , Ingo Molnar Subject: Re: [PATCH] nohz: ensure users are aware boot CPU is not NO_HZ_FULL References: <1390929049-17758-1-git-send-email-paul.gortmaker@windriver.com> <20140129000630.GT9012@linux.vnet.ibm.com> <20140131163817.GC21061@localhost.localdomain> In-Reply-To: <20140131163817.GC21061@localhost.localdomain> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [128.224.146.65] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14-01-31 11:38 AM, Frederic Weisbecker wrote: > On Tue, Jan 28, 2014 at 04:06:30PM -0800, Paul E. McKenney wrote: >> On Tue, Jan 28, 2014 at 12:10:49PM -0500, Paul Gortmaker wrote: >>> This bit of information is in the Kconfig help text: >>> >>> Note the boot CPU will still be kept outside the range to >>> handle the timekeeping duty. >>> >>> However neither the variable NO_HZ_FULL_ALL, or the prompt >>> convey this important detail, so lets add it to the prompt >>> to make it more explicitly obvious to the average user. >>> >>> Cc: Frederic Weisbecker >>> Cc: "Paul E. McKenney" >>> Signed-off-by: Paul Gortmaker >> >> Acked-by: Paul E. McKenney >> >>> --- >>> kernel/time/Kconfig | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig >>> index 3ce6e8c5f3fc..76a1fbef1fd8 100644 >>> --- a/kernel/time/Kconfig >>> +++ b/kernel/time/Kconfig >>> @@ -124,7 +124,7 @@ config NO_HZ_FULL >>> endchoice >>> >>> config NO_HZ_FULL_ALL >>> - bool "Full dynticks system on all CPUs by default" >>> + bool "Full dynticks system on all (but boot) CPUs by default" > > Looks good. Now we are all using "boot CPU" to refer to the CPU 0, but it may > not sound that obvious to everyone. > > How about: "Full dynticks system on all CPUs by default (expect CPU 0)" ? Sure, I'll send a v2 with the above, but I'll s/expect/except/ :) Thanks, Paul. -- > > Sure this is a temporary behaviour until I get the sysidle detection use patchset in shape, > but indeed worth a big fat warning until we sort it out. > > Thanks! > >>> depends on NO_HZ_FULL >>> help >>> If the user doesn't pass the nohz_full boot option to >>> -- >>> 1.8.5.2 >>> >> -- 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/