Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933879AbbDYPnv (ORCPT ); Sat, 25 Apr 2015 11:43:51 -0400 Received: from mx6-phx2.redhat.com ([209.132.183.39]:59607 "EHLO mx6-phx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933740AbbDYPnk (ORCPT ); Sat, 25 Apr 2015 11:43:40 -0400 Date: Sat, 25 Apr 2015 11:42:43 -0400 (EDT) From: Ulrich Obergfell To: Don Zickus Cc: Chris Metcalf , Frederic Weisbecker , Ingo Molnar , Andrew Morton , Andrew Jones , chai wen , Fabian Frederick , Aaron Tomlin , Ben Zhang , Christoph Lameter , Gilad Ben-Yossef , Steven Rostedt , linux-kernel@vger.kernel.org, Jonathan Corbet , linux-doc@vger.kernel.org, Thomas Gleixner , Peter Zijlstra Message-ID: <661586056.6758573.1429976563176.JavaMail.zimbra@redhat.com> In-Reply-To: <20150422151823.GV98296@redhat.com> References: <20150416152808.GA16270@lerouge> <1429295838-6328-1-git-send-email-cmetcalf@ezchip.com> <1429295838-6328-2-git-send-email-cmetcalf@ezchip.com> <1642563828.4126628.1429625220545.JavaMail.zimbra@redhat.com> <20150422151823.GV98296@redhat.com> Subject: Re: [PATCH v9 2/3] watchdog: add watchdog_cpumask sysctl to assist nohz MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.36.6.206] X-Mailer: Zimbra 8.0.6_GA_5922 (ZimbraWebClient - FF22 (Linux)/8.0.6_GA_5922) Thread-Topic: watchdog: add watchdog_cpumask sysctl to assist nohz Thread-Index: B5hvuJIuwMyFnEZD0NpyPvJ3xByiPQ== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1137 Lines: 38 ----- Original Message ----- From: "Don Zickus" [...] > On Tue, Apr 21, 2015 at 10:07:00AM -0400, Ulrich Obergfell wrote: >> >> Chris, >> [...] >> I think the user should only be allowed to specify a mask that is a subset of >> tick_nohz_full_mask as only those CPUs don't have a watchdog thread by default. >> In other words, the user should not be able to interfere with housekeeping CPUs. > > Hi Uli, > > I am not sure that is necessary. This was supposed to be a debugging > interface for nohz (and possibly other technologies). I think restricting > it to just tick_nohz makes it difficult to try out new things or debug > certain problems. > > Personally, I feel anyone who will use this sys interface will need to do so > at their own risk. > > > Cheers, > Don Don, o.k. - I understand. Chris, please ignore my idea to add a plausibility check. Regards, Uli -- 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/