Userspace notifier watchdog pretimeout governor, on watchdog pretimeout event sends a notification to userspace for further handling.
Signed-off-by: Vladimir Zapolskiy <[email protected]> --- Changes from v1 to v2: * removed #ifdef CONFIG_WATCHDOG_PRETIMEOUT_DEFAULT_GOV_USERSPACE, now this selection is done in a centralized manner, * added .can_sleep attribute, * added module owner reference to count users of the governor, * slightly improved description of the governors in Kconfig. drivers/watchdog/Kconfig | 16 +++++++++++ drivers/watchdog/Makefile | 1 + drivers/watchdog/pretimeout_userspace.c | 48 +++++++++++++++++++++++++++++++++ drivers/watchdog/watchdog_pretimeout.h | 2 ++ 4 files changed, 67 insertions(+) create mode 100644 drivers/watchdog/pretimeout_userspace.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 48062ec..31e67f4 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1659,6 +1659,15 @@ config WATCHDOG_PRETIMEOUT_DEFAULT_GOV_NOOP governor is selected by a user, write a short message to the kernel log buffer and don't do any system changes. +config WATCHDOG_PRETIMEOUT_DEFAULT_GOV_USERSPACE + bool "userspace" + select WATCHDOG_PRETIMEOUT_GOV_USERSPACE + help + Use userspace watchdog pretimeout governor by default, + the governor sends a device state change uevent + notification, if a pretimeout event a reported by a + watchdog. + endchoice config WATCHDOG_PRETIMEOUT_GOV_PANIC @@ -1675,6 +1684,13 @@ config WATCHDOG_PRETIMEOUT_GOV_NOOP governor, only an informational message is added to the kernel log buffer, if watchdog pretimeout is happened. +config WATCHDOG_PRETIMEOUT_GOV_USERSPACE + tristate "Userspace notifier watchdog pretimeout governor" + help + Userspace notifier watchdog pretimeout governor, on watchdog + pretimeout event send a notification to userspace for + further handling. + endif # WATCHDOG_PRETIMEOUT_GOV endif # WATCHDOG diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index b45b1ef..2dd91ae 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -11,6 +11,7 @@ watchdog-$(CONFIG_WATCHDOG_PRETIMEOUT_GOV) += watchdog_pretimeout.o obj-$(CONFIG_WATCHDOG_PRETIMEOUT_GOV_PANIC) += pretimeout_panic.o obj-$(CONFIG_WATCHDOG_PRETIMEOUT_GOV_NOOP) += pretimeout_noop.o +obj-$(CONFIG_WATCHDOG_PRETIMEOUT_GOV_USERSPACE) += pretimeout_userspace.o # Only one watchdog can succeed. We probe the ISA/PCI/USB based # watchdog-cards first, then the architecture specific watchdog diff --git a/drivers/watchdog/pretimeout_userspace.c b/drivers/watchdog/pretimeout_userspace.c new file mode 100644 index 0000000..bdaa70c --- /dev/null +++ b/drivers/watchdog/pretimeout_userspace.c @@ -0,0 +1,48 @@ +/* + * 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_userspace - Notify userspace on watchdog pretimeout event + * @wdd - watchdog_device + * + * Send watchdog device uevent to userspace to handle pretimeout event + */ +static void pretimeout_userspace(struct watchdog_device *wdd) +{ + kobject_uevent(&wdd->dev->kobj, KOBJ_CHANGE); +} + +static struct watchdog_governor watchdog_gov_userspace = { + .name = "userspace", + .pretimeout = pretimeout_userspace, + .can_sleep = true, + .owner = THIS_MODULE, +}; + +static int __init watchdog_gov_userspace_register(void) +{ + return watchdog_register_governor(&watchdog_gov_userspace); +} + +static void __exit watchdog_gov_userspace_unregister(void) +{ + watchdog_unregister_governor(&watchdog_gov_userspace); +} +module_init(watchdog_gov_userspace_register); +module_exit(watchdog_gov_userspace_unregister); + +MODULE_AUTHOR("Vladimir Zapolskiy <[email protected]>"); +MODULE_DESCRIPTION("Userspace notifier watchdog pretimeout governor"); +MODULE_LICENSE("GPL"); diff --git a/drivers/watchdog/watchdog_pretimeout.h b/drivers/watchdog/watchdog_pretimeout.h index 2124a173..21c6b72 100644 --- a/drivers/watchdog/watchdog_pretimeout.h +++ b/drivers/watchdog/watchdog_pretimeout.h @@ -24,6 +24,8 @@ void watchdog_unregister_governor(struct watchdog_governor *gov); #define WATCHDOG_PRETIMEOUT_DEFAULT_GOV "panic" #elif IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_DEFAULT_GOV_NOOP) #define WATCHDOG_PRETIMEOUT_DEFAULT_GOV "noop" +#elif IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_DEFAULT_GOV_USERSPACE) +#define WATCHDOG_PRETIMEOUT_DEFAULT_GOV "userspace" #else #error "Default watchdog pretimeout governor is not set." #endif -- 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
