From patchwork Tue Sep 12 19:36:57 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 9950011 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id E70DF603F4 for ; Tue, 12 Sep 2017 19:54:14 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D98E529020 for ; Tue, 12 Sep 2017 19:54:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CE158290A7; Tue, 12 Sep 2017 19:54:14 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6BE1729020 for ; Tue, 12 Sep 2017 19:54:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751542AbdILTxY (ORCPT ); Tue, 12 Sep 2017 15:53:24 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:36301 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751544AbdILTtW (ORCPT ); Tue, 12 Sep 2017 15:49:22 -0400 Received: from localhost ([127.0.0.1] helo=[127.0.1.1]) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1drr9Q-0002D0-9P; Tue, 12 Sep 2017 21:47:16 +0200 Message-Id: <20170912194146.327343752@linutronix.de> User-Agent: quilt/0.63-1 Date: Tue, 12 Sep 2017 21:36:57 +0200 From: Thomas Gleixner To: LKML Cc: Ingo Molnar , Peter Zijlstra , Borislav Petkov , Andrew Morton , Sebastian Siewior , Nicholas Piggin , Don Zickus , Chris Metcalf , Ulrich Obergfell , linux-parisc@vger.kernel.org, Helge Deller Subject: [patch V2 03/29] lockup_detector: Provide interface to stop from poweroff() References: <20170912193654.321505854@linutronix.de> MIME-Version: 1.0 Content-Disposition: inline; filename=lockup_detector_Provide_interface_to_stop_from_poweroff().patch Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP PARISC has a a busy looping power off routine. If the watchdog is enabled the watchdog timer will still fire, but the thread is not running, which causes the softlockup watchdog to trigger. Provide a interface which allows to turn the watchdog off. Signed-off-by: Thomas Gleixner Cc: Don Zickus Cc: Chris Metcalf Cc: linux-parisc@vger.kernel.org Cc: Peter Zijlstra Cc: Sebastian Siewior Cc: Nicholas Piggin Cc: Ulrich Obergfell Cc: Borislav Petkov Cc: Andrew Morton Cc: Helge Deller Link: http://lkml.kernel.org/r/20170831073053.202164272@linutronix.de --- include/linux/nmi.h | 6 +++--- kernel/watchdog.c | 14 +++++++++++++- 2 files changed, 16 insertions(+), 4 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -12,10 +12,10 @@ #ifdef CONFIG_LOCKUP_DETECTOR void lockup_detector_init(void); +void lockup_detector_soft_poweroff(void); #else -static inline void lockup_detector_init(void) -{ -} +static inline void lockup_detector_init(void) { } +static inline void lockup_detector_soft_poweroff(void) { } #endif #ifdef CONFIG_SOFTLOCKUP_DETECTOR --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -333,7 +333,8 @@ static enum hrtimer_restart watchdog_tim int duration; int softlockup_all_cpu_backtrace = sysctl_softlockup_all_cpu_backtrace; - if (atomic_read(&watchdog_park_in_progress) != 0) + if (!watchdog_enabled || + atomic_read(&watchdog_park_in_progress) != 0) return HRTIMER_NORESTART; /* kick the hardlockup detector */ @@ -660,6 +661,17 @@ static void set_sample_period(void) } #endif /* SOFTLOCKUP */ +/** + * lockup_detector_soft_poweroff - Interface to stop lockup detector(s) + * + * Special interface for parisc. It prevents lockup detector warnings from + * the default pm_poweroff() function which busy loops forever. + */ +void lockup_detector_soft_poweroff(void) +{ + watchdog_enabled = 0; +} + /* * Suspend the hard and soft lockup detector by parking the watchdog threads. */