Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758613Ab2BIWmz (ORCPT ); Thu, 9 Feb 2012 17:42:55 -0500 Received: from mx1.redhat.com ([209.132.183.28]:22025 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753210Ab2BIWmx (ORCPT ); Thu, 9 Feb 2012 17:42:53 -0500 From: Don Zickus To: LKML Cc: Ingo Molnar , Andrew Morton , =?UTF-8?q?Fernando=20Luis=20V=C3=A1zquez=20Cao?= , Don Zickus Subject: [PATCH 2/3] watchdog: update Kconfig entries Date: Thu, 9 Feb 2012 17:42:21 -0500 Message-Id: <1328827342-6253-2-git-send-email-dzickus@redhat.com> In-Reply-To: <1328827342-6253-1-git-send-email-dzickus@redhat.com> References: <1328827342-6253-1-git-send-email-dzickus@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3023 Lines: 71 From: Fernando Luis Vázquez Cao The soft and hard lockup thresholds have changed so the corresponding Kconfig entries need to be updated accordingly. Add a reference to watchdog_thresh while at it. Signed-off-by: Fernando Luis Vazquez Cao Signed-off-by: Don Zickus --- lib/Kconfig.debug | 18 +++++++++++------- 1 files changed, 11 insertions(+), 7 deletions(-) diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 63696aa..1e37364 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -166,18 +166,21 @@ config LOCKUP_DETECTOR hard and soft lockups. Softlockups are bugs that cause the kernel to loop in kernel - mode for more than 60 seconds, without giving other tasks a + mode for more than 20 seconds, without giving other tasks a chance to run. The current stack trace is displayed upon detection and the system will stay locked up. Hardlockups are bugs that cause the CPU to loop in kernel mode - for more than 60 seconds, without letting other interrupts have a + for more than 10 seconds, without letting other interrupts have a chance to run. The current stack trace is displayed upon detection and the system will stay locked up. The overhead should be minimal. A periodic hrtimer runs to - generate interrupts and kick the watchdog task every 10-12 seconds. - An NMI is generated every 60 seconds or so to check for hardlockups. + generate interrupts and kick the watchdog task every 4 seconds. + An NMI is generated every 10 seconds or so to check for hardlockups. + + The frequency of hrtimer and NMI events and the soft and hard lockup + thresholds can be controlled through the sysctl watchdog_thresh. config HARDLOCKUP_DETECTOR def_bool LOCKUP_DETECTOR && PERF_EVENTS && HAVE_PERF_EVENTS_NMI && \ @@ -189,7 +192,8 @@ config BOOTPARAM_HARDLOCKUP_PANIC help Say Y here to enable the kernel to panic on "hard lockups", which are bugs that cause the kernel to loop in kernel - mode with interrupts disabled for more than 60 seconds. + mode with interrupts disabled for more than 10 seconds (configurable + using the watchdog_thresh sysctl). Say N if unsure. @@ -206,8 +210,8 @@ config BOOTPARAM_SOFTLOCKUP_PANIC help Say Y here to enable the kernel to panic on "soft lockups", which are bugs that cause the kernel to loop in kernel - mode for more than 60 seconds, without giving other tasks a - chance to run. + mode for more than 20 seconds (configurable using the watchdog_thresh + sysctl), without giving other tasks a chance to run. The panic can be used in combination with panic_timeout, to cause the system to reboot automatically after a -- 1.7.7.6 -- 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/