From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756193AbcFGRkj (ORCPT ); Tue, 7 Jun 2016 13:40:39 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:39276 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756064AbcFGRi7 (ORCPT ); Tue, 7 Jun 2016 13:38:59 -0400 From: Vladimir Zapolskiy To: Wim Van Sebroeck , Guenter Roeck CC: Wolfram Sang , Robin Gong , , Subject: [PATCH v3 5/6] watchdog: pretimeout: add panic pretimeout governor Date: Tue, 7 Jun 2016 20:38:46 +0300 Message-ID: <1465321127-19522-6-git-send-email-vladimir_zapolskiy@mentor.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1465321127-19522-1-git-send-email-vladimir_zapolskiy@mentor.com> References: <1465321127-19522-1-git-send-email-vladimir_zapolskiy@mentor.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [137.202.0.76] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Panic watchdog pretimeout governor, on watchdog pretimeout event the kernel shall panic. Signed-off-by: Vladimir Zapolskiy --- Changes from v2 to v3: * temporarily removed tristate option, the governor can be built-in only Changes from v1 to v2: * removed #ifdef CONFIG_WATCHDOG_PRETIMEOUT_DEFAULT_GOV_PANIC, now this selection is done in a centralized manner, * added module owner reference to count users of the governor, * slightly improved description of the governors in Kconfig. drivers/watchdog/Kconfig | 25 ++++++++++++++++++ drivers/watchdog/Makefile | 2 ++ drivers/watchdog/pretimeout_panic.c | 47 ++++++++++++++++++++++++++++++++++ drivers/watchdog/watchdog_pretimeout.h | 4 +++ 4 files changed, 78 insertions(+) create mode 100644 drivers/watchdog/pretimeout_panic.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 354217e..bf5938a 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1808,4 +1808,29 @@ config WATCHDOG_PRETIMEOUT_GOV help The option allows to select watchdog pretimeout governors. +if WATCHDOG_PRETIMEOUT_GOV + +choice + prompt "Default Watchdog Pretimeout Governor" + default WATCHDOG_PRETIMEOUT_DEFAULT_GOV_PANIC + help + This option selects a default watchdog pretimeout governor. + The governor takes its action, if a watchdog is capable + to report a pretimeout event. + +config WATCHDOG_PRETIMEOUT_DEFAULT_GOV_PANIC + bool "panic" + select WATCHDOG_PRETIMEOUT_GOV_PANIC + help + Use panic watchdog pretimeout governor by default, if + a watchdog pretimeout event happens, consider that + a watchdog feeder is dead and reboot is unavoidable. + +endchoice + +config WATCHDOG_PRETIMEOUT_GOV_PANIC + bool + +endif # WATCHDOG_PRETIMEOUT_GOV + endif # WATCHDOG diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index cca47de..12df9c7 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -9,6 +9,8 @@ watchdog-objs += watchdog_core.o watchdog_dev.o watchdog-$(CONFIG_WATCHDOG_PRETIMEOUT_GOV) += watchdog_pretimeout.o +obj-$(CONFIG_WATCHDOG_PRETIMEOUT_GOV_PANIC) += pretimeout_panic.o + # Only one watchdog can succeed. We probe the ISA/PCI/USB based # watchdog-cards first, then the architecture specific watchdog # drivers and then the architecture independent "softdog" driver. diff --git a/drivers/watchdog/pretimeout_panic.c b/drivers/watchdog/pretimeout_panic.c new file mode 100644 index 0000000..4d5338d --- /dev/null +++ b/drivers/watchdog/pretimeout_panic.c @@ -0,0 +1,47 @@ +/* + * Copyright (C) 2015-2016 Mentor Graphics + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include +#include +#include + +#include + +/** + * pretimeout_panic - Panic on watchdog pretimeout event + * @wdd - watchdog_device + * + * Panic, watchdog has not been fed till pretimeout event. + */ +static void pretimeout_panic(struct watchdog_device *wdd) +{ + panic("panic on watchdog pretimeout event\n"); +} + +static struct watchdog_governor watchdog_gov_panic = { + .name = "panic", + .pretimeout = pretimeout_panic, +}; + +static int __init watchdog_gov_panic_register(void) +{ + return watchdog_register_governor(&watchdog_gov_panic); +} + +static void __exit watchdog_gov_panic_unregister(void) +{ + watchdog_unregister_governor(&watchdog_gov_panic); +} +module_init(watchdog_gov_panic_register); +module_exit(watchdog_gov_panic_unregister); + +MODULE_AUTHOR("Vladimir Zapolskiy "); +MODULE_DESCRIPTION("Panic watchdog pretimeout governor"); +MODULE_LICENSE("GPL"); diff --git a/drivers/watchdog/watchdog_pretimeout.h b/drivers/watchdog/watchdog_pretimeout.h index 9e08d56..8f2565e 100644 --- a/drivers/watchdog/watchdog_pretimeout.h +++ b/drivers/watchdog/watchdog_pretimeout.h @@ -22,6 +22,10 @@ void watchdog_unregister_pretimeout(struct watchdog_device *wdd); /* Interfaces to watchdog_dev.c */ int watchdog_pretimeout_governor_name(struct watchdog_device *wdd, char *buf); +#if IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_DEFAULT_GOV_PANIC) +#define WATCHDOG_PRETIMEOUT_DEFAULT_GOV "panic" +#endif + #else static inline int watchdog_register_pretimeout(struct watchdog_device *wdd) { -- 2.5.0