diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/watchdog/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/watchdog/Makefile | 1 | ||||
| -rw-r--r-- | drivers/watchdog/watchdog_core.h | 48 | ||||
| -rw-r--r-- | drivers/watchdog/watchdog_dev.c | 47 | ||||
| -rw-r--r-- | drivers/watchdog/watchdog_hrtimer_pretimeout.c | 44 | ||||
| -rw-r--r-- | drivers/watchdog/watchdog_pretimeout.c | 5 |
6 files changed, 121 insertions, 32 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index fcc61c948f01..7a33e6a6ac23 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -73,6 +73,14 @@ config WATCHDOG_SYSFS Say Y here if you want to enable watchdog device status read through sysfs attributes. +config WATCHDOG_HRTIMER_PRETIMEOUT + bool "Enable watchdog hrtimer-based pretimeouts" + help + Enable this if you want to use a hrtimer timer based pretimeout for + watchdogs that do not natively support pretimeout support. Be aware + that because this pretimeout functionality uses hrtimers, it may not + be able to fire before the actual watchdog fires in some situations. + comment "Watchdog Pretimeout Governors" config WATCHDOG_PRETIMEOUT_GOV diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 578bd6e5fbd0..0b4d828872be 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -9,6 +9,7 @@ obj-$(CONFIG_WATCHDOG_CORE) += watchdog.o watchdog-objs += watchdog_core.o watchdog_dev.o watchdog-$(CONFIG_WATCHDOG_PRETIMEOUT_GOV) += watchdog_pretimeout.o +watchdog-$(CONFIG_WATCHDOG_HRTIMER_PRETIMEOUT) += watchdog_hrtimer_pretimeout.o obj-$(CONFIG_WATCHDOG_PRETIMEOUT_GOV_NOOP) += pretimeout_noop.o obj-$(CONFIG_WATCHDOG_PRETIMEOUT_GOV_PANIC) += pretimeout_panic.o diff --git a/drivers/watchdog/watchdog_core.h b/drivers/watchdog/watchdog_core.h index a5062e8e0d13..5b35a8439e26 100644 --- a/drivers/watchdog/watchdog_core.h +++ b/drivers/watchdog/watchdog_core.h @@ -7,6 +7,8 @@ * * (c) Copyright 2008-2011 Wim Van Sebroeck <wim@iguana.be>. * + * (c) Copyright 2021 Hewlett Packard Enterprise Development LP. + * * This source code is part of the generic code that can be used * by all the watchdog timer drivers. * @@ -22,12 +24,58 @@ * This material is provided "AS-IS" and at no charge. */ +#include <linux/hrtimer.h> +#include <linux/kthread.h> + #define MAX_DOGS 32 /* Maximum number of watchdog devices */ /* + * struct watchdog_core_data - watchdog core internal data + * @dev: The watchdog's internal device + * @cdev: The watchdog's Character device. + * @wdd: Pointer to watchdog device. + * @lock: Lock for watchdog core. + * @status: Watchdog core internal status bits. + */ +struct watchdog_core_data { + struct device dev; + struct cdev cdev; + struct watchdog_device *wdd; + struct mutex lock; + ktime_t last_keepalive; + ktime_t last_hw_keepalive; + ktime_t open_deadline; + struct hrtimer timer; + struct kthread_work work; +#if IS_ENABLED(CONFIG_WATCHDOG_HRTIMER_PRETIMEOUT) + struct hrtimer pretimeout_timer; +#endif + unsigned long status; /* Internal status bits */ +#define _WDOG_DEV_OPEN 0 /* Opened ? */ +#define _WDOG_ALLOW_RELEASE 1 /* Did we receive the magic char ? */ +#define _WDOG_KEEPALIVE 2 /* Did we receive a keepalive ? */ +}; + +/* * Functions/procedures to be called by the core */ extern int watchdog_dev_register(struct watchdog_device *); extern void watchdog_dev_unregister(struct watchdog_device *); extern int __init watchdog_dev_init(void); extern void __exit watchdog_dev_exit(void); + +static inline bool watchdog_have_pretimeout(struct watchdog_device *wdd) +{ + return wdd->info->options & WDIOF_PRETIMEOUT || + IS_ENABLED(CONFIG_WATCHDOG_HRTIMER_PRETIMEOUT); +} + +#if IS_ENABLED(CONFIG_WATCHDOG_HRTIMER_PRETIMEOUT) +void watchdog_hrtimer_pretimeout_init(struct watchdog_device *wdd); +void watchdog_hrtimer_pretimeout_start(struct watchdog_device *wdd); +void watchdog_hrtimer_pretimeout_stop(struct watchdog_device *wdd); +#else +static inline void watchdog_hrtimer_pretimeout_init(struct watchdog_device *wdd) {} +static inline void watchdog_hrtimer_pretimeout_start(struct watchdog_device *wdd) {} +static inline void watchdog_hrtimer_pretimeout_stop(struct watchdog_device *wdd) {} +#endif diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c index 7c1007ab1b71..3bab32485273 100644 --- a/drivers/watchdog/watchdog_dev.c +++ b/drivers/watchdog/watchdog_dev.c @@ -7,6 +7,7 @@ * * (c) Copyright 2008-2011 Wim Van Sebroeck <wim@iguana.be>. * + * (c) Copyright 2021 Hewlett Packard Enterprise Development LP. * * This source code is part of the generic code that can be used * by all the watchdog timer drivers. @@ -46,30 +47,6 @@ #include "watchdog_core.h" #include "watchdog_pretimeout.h" -/* - * struct watchdog_core_data - watchdog core internal data - * @dev: The watchdog's internal device - * @cdev: The watchdog's Character device. - * @wdd: Pointer to watchdog device. - * @lock: Lock for watchdog core. - * @status: Watchdog core internal status bits. - */ -struct watchdog_core_data { - struct device dev; - struct cdev cdev; - struct watchdog_device *wdd; - struct mutex lock; - ktime_t last_keepalive; - ktime_t last_hw_keepalive; - ktime_t open_deadline; - struct hrtimer timer; - struct kthread_work work; - unsigned long status; /* Internal status bits */ -#define _WDOG_DEV_OPEN 0 /* Opened ? */ -#define _WDOG_ALLOW_RELEASE 1 /* Did we receive the magic char ? */ -#define _WDOG_KEEPALIVE 2 /* Did we receive a keepalive ? */ -}; - /* the dev_t structure to store the dynamically allocated watchdog devices */ static dev_t watchdog_devt; /* Reference to watchdog device behind /dev/watchdog */ @@ -185,6 +162,9 @@ static int __watchdog_ping(struct watchdog_device *wdd) else err = wdd->ops->start(wdd); /* restart watchdog */ + if (err == 0) + watchdog_hrtimer_pretimeout_start(wdd); + watchdog_update_worker(wdd); return err; @@ -275,8 +255,10 @@ static int watchdog_start(struct watchdog_device *wdd) started_at = ktime_get(); if (watchdog_hw_running(wdd) && wdd->ops->ping) { err = __watchdog_ping(wdd); - if (err == 0) + if (err == 0) { set_bit(WDOG_ACTIVE, &wdd->status); + watchdog_hrtimer_pretimeout_start(wdd); + } } else { err = wdd->ops->start(wdd); if (err == 0) { @@ -284,6 +266,7 @@ static int watchdog_start(struct watchdog_device *wdd) wd_data->last_keepalive = started_at; wd_data->last_hw_keepalive = started_at; watchdog_update_worker(wdd); + watchdog_hrtimer_pretimeout_start(wdd); } } @@ -325,6 +308,7 @@ static int watchdog_stop(struct watchdog_device *wdd) if (err == 0) { clear_bit(WDOG_ACTIVE, &wdd->status); watchdog_update_worker(wdd); + watchdog_hrtimer_pretimeout_stop(wdd); } return err; @@ -361,6 +345,9 @@ static unsigned int watchdog_get_status(struct watchdog_device *wdd) if (test_and_clear_bit(_WDOG_KEEPALIVE, &wd_data->status)) status |= WDIOF_KEEPALIVEPING; + if (IS_ENABLED(CONFIG_WATCHDOG_HRTIMER_PRETIMEOUT)) + status |= WDIOF_PRETIMEOUT; + return status; } @@ -408,7 +395,7 @@ static int watchdog_set_pretimeout(struct watchdog_device *wdd, { int err = 0; - if (!(wdd->info->options & WDIOF_PRETIMEOUT)) + if (!watchdog_have_pretimeout(wdd)) return -EOPNOTSUPP; if (watchdog_pretimeout_invalid(wdd, timeout)) @@ -613,13 +600,11 @@ static umode_t wdt_is_visible(struct kobject *kobj, struct attribute *attr, if (attr == &dev_attr_timeleft.attr && !wdd->ops->get_timeleft) mode = 0; - else if (attr == &dev_attr_pretimeout.attr && - !(wdd->info->options & WDIOF_PRETIMEOUT)) + else if (attr == &dev_attr_pretimeout.attr && !watchdog_have_pretimeout(wdd)) mode = 0; else if ((attr == &dev_attr_pretimeout_governor.attr || attr == &dev_attr_pretimeout_available_governors.attr) && - (!(wdd->info->options & WDIOF_PRETIMEOUT) || - !IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_GOV))) + (!watchdog_have_pretimeout(wdd) || !IS_ENABLED(CONFIG_WATCHDOG_PRETIMEOUT_GOV))) mode = 0; return mode; @@ -1030,6 +1015,7 @@ static int watchdog_cdev_register(struct watchdog_device *wdd) kthread_init_work(&wd_data->work, watchdog_ping_work); hrtimer_init(&wd_data->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); wd_data->timer.function = watchdog_timer_expired; + watchdog_hrtimer_pretimeout_init(wdd); if (wdd->id == 0) { old_wd_data = wd_data; @@ -1117,6 +1103,7 @@ static void watchdog_cdev_unregister(struct watchdog_device *wdd) hrtimer_cancel(&wd_data->timer); kthread_cancel_work_sync(&wd_data->work); + watchdog_hrtimer_pretimeout_stop(wdd); put_device(&wd_data->dev); } diff --git a/drivers/watchdog/watchdog_hrtimer_pretimeout.c b/drivers/watchdog/watchdog_hrtimer_pretimeout.c new file mode 100644 index 000000000000..940b53718a91 --- /dev/null +++ b/drivers/watchdog/watchdog_hrtimer_pretimeout.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * (c) Copyright 2021 Hewlett Packard Enterprise Development LP. + */ + +#include <linux/hrtimer.h> +#include <linux/watchdog.h> + +#include "watchdog_core.h" +#include "watchdog_pretimeout.h" + +static enum hrtimer_restart watchdog_hrtimer_pretimeout(struct hrtimer *timer) +{ + struct watchdog_core_data *wd_data; + + wd_data = container_of(timer, struct watchdog_core_data, pretimeout_timer); + + watchdog_notify_pretimeout(wd_data->wdd); + return HRTIMER_NORESTART; +} + +void watchdog_hrtimer_pretimeout_init(struct watchdog_device *wdd) +{ + struct watchdog_core_data *wd_data = wdd->wd_data; + + hrtimer_init(&wd_data->pretimeout_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + wd_data->pretimeout_timer.function = watchdog_hrtimer_pretimeout; +} + +void watchdog_hrtimer_pretimeout_start(struct watchdog_device *wdd) +{ + if (!(wdd->info->options & WDIOF_PRETIMEOUT) && + !watchdog_pretimeout_invalid(wdd, wdd->pretimeout)) + hrtimer_start(&wdd->wd_data->pretimeout_timer, + ktime_set(wdd->timeout - wdd->pretimeout, 0), + HRTIMER_MODE_REL); + else + hrtimer_cancel(&wdd->wd_data->pretimeout_timer); +} + +void watchdog_hrtimer_pretimeout_stop(struct watchdog_device *wdd) +{ + hrtimer_cancel(&wdd->wd_data->pretimeout_timer); +} diff --git a/drivers/watchdog/watchdog_pretimeout.c b/drivers/watchdog/watchdog_pretimeout.c index 7f257c3485cd..376a495ab80c 100644 --- a/drivers/watchdog/watchdog_pretimeout.c +++ b/drivers/watchdog/watchdog_pretimeout.c @@ -9,6 +9,7 @@ #include <linux/string.h> #include <linux/watchdog.h> +#include "watchdog_core.h" #include "watchdog_pretimeout.h" /* Default watchdog pretimeout governor */ @@ -177,7 +178,7 @@ int watchdog_register_pretimeout(struct watchdog_device *wdd) { struct watchdog_pretimeout *p; - if (!(wdd->info->options & WDIOF_PRETIMEOUT)) + if (!watchdog_have_pretimeout(wdd)) return 0; p = kzalloc(sizeof(*p), GFP_KERNEL); @@ -197,7 +198,7 @@ void watchdog_unregister_pretimeout(struct watchdog_device *wdd) { struct watchdog_pretimeout *p, *t; - if (!(wdd->info->options & WDIOF_PRETIMEOUT)) + if (!watchdog_have_pretimeout(wdd)) return; spin_lock_irq(&pretimeout_lock); |