Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933123AbaDIL66 (ORCPT ); Wed, 9 Apr 2014 07:58:58 -0400 Received: from mail-oa0-f53.google.com ([209.85.219.53]:57333 "EHLO mail-oa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932560AbaDIL65 (ORCPT ); Wed, 9 Apr 2014 07:58:57 -0400 MIME-Version: 1.0 Date: Wed, 9 Apr 2014 17:28:57 +0530 Message-ID: Subject: [Query]: tick-sched: can idle_active be false in tick_nohz_idle_exit()? From: Viresh Kumar To: =?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?= , Thomas Gleixner Cc: Linux Kernel Mailing List , Lists linaro-kernel Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Guys, File: kernel/time/tick-sched.c function: tick_nohz_idle_exit() We are checking here if idle_active is true or not and then do some stuff. But is it possible that idle_active be false here? The sequence as far as I understood is: idle-loop: tick_nohz_idle_enter(), i.e. idle_active = true; local_irq_disable() IDLE . . wake up due to IPI ?? local_irq_enable() tick_nohz_irq_enter(), i.e. idle_active = false; tick_nohz_irq_exit(), i.e. idle_active = true; tick_nohz_idle_exit() How can idle_active be false here? -- viresh -- 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/