Userspace notifier watchdog pretimeout governor, on watchdog
pretimeout event sends a notification to userspace for further
handling.
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@xxxxxxxxxx>
---
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 <vladimir_zapolskiy@xxxxxxxxxx>");
+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 majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
