From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753327AbcHOPE2 (ORCPT ); Mon, 15 Aug 2016 11:04:28 -0400 Received: from mail-db5eur01on0044.outbound.protection.outlook.com ([104.47.2.44]:60672 "EHLO EUR01-DB5-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753115AbcHOPEX (ORCPT ); Mon, 15 Aug 2016 11:04:23 -0400 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=cmetcalf@mellanox.com; Subject: Re: clocksource_watchdog causing scheduling of timers every second (was [v13] support "task_isolation" mode) To: Frederic Weisbecker , Peter Zijlstra , Christoph Lameter References: <1468529299-27929-1-git-send-email-cmetcalf@mellanox.com> <7a3f66f7-5011-7d59-2e0e-f57e4e42e6b6@mellanox.com> <20160810221656.GC19757@lerouge> <20160811084002.GV30192@twins.programming.kicks-ass.net> <20160811115845.GA4214@lerouge> CC: Gilad Ben Yossef , Steven Rostedt , Ingo Molnar , Andrew Morton , Rik van Riel , Tejun Heo , Thomas Gleixner , "Paul E. McKenney" , Viresh Kumar , "Catalin Marinas" , Will Deacon , "Andy Lutomirski" , Daniel Lezcano , , , From: Chris Metcalf Message-ID: <142f7676-0a0f-897c-0482-69d52511df57@mellanox.com> Date: Mon, 15 Aug 2016 11:03:54 -0400 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <20160811115845.GA4214@lerouge> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [12.216.194.146] X-ClientProxiedBy: DM5PR08CA0014.namprd08.prod.outlook.com (10.175.218.24) To AM4PR0501MB2756.eurprd05.prod.outlook.com (10.172.216.12) X-MS-Office365-Filtering-Correlation-Id: 7c021f14-5a55-419e-8587-08d3c51d6bc8 X-Microsoft-Exchange-Diagnostics: 1;AM4PR0501MB2756;2:YagsYF5ieMLSsrVUWFv+1kcHFXajPwJvJLQ59YBrS+/8TsyXVmGG6hVuChokFSgdepda5Y3wpuTt2+9P0yvY3B7zfPB+0x0svhXbVNgczOq0mbywq/gLF6WU540VkJ2nZXn72xtKuG2U1M5pXqyJCqEcKB5GqRpZhD7aOm8Hn/Mw6rfLeEMF7RFOj48HgmGv;3:FdE+sb1Dyi8YOzCEpxCzMlfOIqvPvAN1t/NxPIj9Rj1uTvuZ3bwnO/MzkUBSkV9PlQODAL2ztvPSD0ZATUYe7dUR335tjXHO83U6j/VXfbYyBWEV2s6qnKNhkEmdBq7u;25:Ebv5IJ/hdJFWCY8p9bhsg8moM21/jBjAvFeIKcZnYzUL0l2GewLBs8UwMM/3v6xiV8ZWcmboCmWlVKEwPSLkfCDiMpUWeo5BZ1KtwE/zdxg2g72MZPNPRBaYAtp4jnl4IuEaQcAtf+Fkqj/kUE0L+dX5gTNRMzr0bF+eezNs4BDz6DjPbVJ1uomqbEtFXPx1i4Rz8emNPewdG9LYyoZOX0oMjnpJkDjRxtIz6AUp5cDUf8R6gbhQCm4jBgup+EoabV01wkAOjH1zlnIeyQ5oS6C8+pncDA0p3FYrofpd/W2tWMkoQLymhgvXYcz0MIHkuAE8cTA451loO+ifaPk/iVEAiIXWRR0j+zeJGwv81B/MeYw6tjzIG9j8zCK9JSusM+ZRGTb8aHq3x15ekiV/qn6jIYKzTipOqCE0SZ9hvOc= X-Microsoft-Antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:AM4PR0501MB2756; 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We do that when tsc is unstable but indeed we can't > seriously run NOHZ_FULL on a non-reliable tsc. > > I'll take care of that warning. Thanks. So I will drop Christoph's patch to run the TSC watchdog on just housekeeping cores and we will rely on the "boot time warning" instead. -- Chris Metcalf, Mellanox Technologies http://www.mellanox.com