From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752370AbbJZVNf (ORCPT ); Mon, 26 Oct 2015 17:13:35 -0400 Received: from mail-db3on0056.outbound.protection.outlook.com ([157.55.234.56]:16096 "EHLO emea01-db3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751076AbbJZVNc (ORCPT ); Mon, 26 Oct 2015 17:13:32 -0400 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=cmetcalf@ezchip.com; Subject: Re: [PATCH v8 04/14] task_isolation: add initial support To: Steven Rostedt , Andy Lutomirski References: <1445373372-6567-1-git-send-email-cmetcalf@ezchip.com> <1445373372-6567-5-git-send-email-cmetcalf@ezchip.com> <5626B00E.3010309@ezchip.com> <20151020202929.485a1ef0@grimm.local.home> CC: Gilad Ben Yossef , Ingo Molnar , Peter Zijlstra , Andrew Morton , Rik van Riel , Tejun Heo , Frederic Weisbecker , Thomas Gleixner , "Paul E. 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I recall something like that. Paul? The current patch series supports that by testing tick_nohz_tick_stopped(), which internally only becomes true after tick_nohz_stop_sched_tick() manages to stop the tick, and it won't if rcu_needs_cpu() is true. -- Chris Metcalf, EZChip Semiconductor http://www.ezchip.com