Panic watchdog pretimeout governor, on watchdog pretimeout event the kernel shall panic.
Signed-off-by: Vladimir Zapolskiy <[email protected]> --- 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 | 29 +++++++++++++++++++++ drivers/watchdog/Makefile | 2 ++ drivers/watchdog/pretimeout_panic.c | 47 ++++++++++++++++++++++++++++++++++ drivers/watchdog/watchdog_pretimeout.h | 7 +++++ 4 files changed, 85 insertions(+) create mode 100644 drivers/watchdog/pretimeout_panic.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 8613639..8eccc93 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1633,4 +1633,33 @@ 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 + tristate "Panic watchdog pretimeout governor" + help + Select this option to enable panic watchdog pretimeout + governor, on a watchdog pretimeout event the kernel shall + panic before an expected system reboot. + +endif # WATCHDOG_PRETIMEOUT_GOV + endif # WATCHDOG diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 6749cac..127f342 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..1d439f4 --- /dev/null +++ b/drivers/watchdog/pretimeout_panic.c @@ -0,0 +1,47 @@ +/* + * Copyright (C) 2015 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 <linux/module.h> +#include <linux/watchdog.h> + +#include <watchdog_pretimeout.h> + +/** + * 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, + .owner = THIS_MODULE, +}; + +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 <[email protected]>"); +MODULE_DESCRIPTION("Panic watchdog pretimeout governor"); +MODULE_LICENSE("GPL"); diff --git a/drivers/watchdog/watchdog_pretimeout.h b/drivers/watchdog/watchdog_pretimeout.h index e888424f..cf28267 100644 --- a/drivers/watchdog/watchdog_pretimeout.h +++ b/drivers/watchdog/watchdog_pretimeout.h @@ -19,6 +19,13 @@ void watchdog_unregister_governor(struct watchdog_governor *gov); /* Interfaces to watchdog_core.c */ #ifdef CONFIG_WATCHDOG_PRETIMEOUT_GOV + +#if IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_DEFAULT_GOV_PANIC) +#define WATCHDOG_PRETIMEOUT_DEFAULT_GOV "panic" +#else +#error "Default watchdog pretimeout governor is not set." +#endif + int watchdog_register_pretimeout(struct watchdog_device *wdd); void watchdog_unregister_pretimeout(struct watchdog_device *wdd); #else -- 2.5.0 -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
