diff options
| -rw-r--r-- | drivers/base/power/main.c | 73 | ||||
| -rw-r--r-- | kernel/power/Kconfig | 16 | ||||
| -rw-r--r-- | kernel/power/user.c | 20 |
3 files changed, 99 insertions, 10 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 9f098a8..ee039af 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -30,6 +30,8 @@ #include <linux/suspend.h> #include <trace/events/power.h> #include <linux/cpuidle.h> +#include <linux/timer.h> + #include "../base.h" #include "power.h" @@ -390,6 +392,71 @@ static int dpm_run_callback(pm_callback_t cb, struct device *dev, return error; } +#ifdef CONFIG_DPM_WATCHDOG +struct dpm_watchdog { + struct device *dev; + struct task_struct *tsk; + struct timer_list timer; +}; + +#define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \ + struct dpm_watchdog wd + +/** + * dpm_watchdog_handler - Driver suspend / resume watchdog handler. + * @data: Watchdog object address. + * + * Called when a driver has timed out suspending or resuming. + * There's not much we can do here to recover so panic() to + * capture a crash-dump in pstore. + */ +static void dpm_watchdog_handler(unsigned long data) +{ + struct dpm_watchdog *wd = (void *)data; + + dev_emerg(wd->dev, "**** DPM device timeout ****\n"); + show_stack(wd->tsk, NULL); + panic("%s %s: unrecoverable failure\n", + dev_driver_string(wd->dev), dev_name(wd->dev)); +} + +/** + * dpm_watchdog_set - Enable pm watchdog for given device. + * @wd: Watchdog. Must be allocated on the stack. + * @dev: Device to handle. + */ +static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev) +{ + struct timer_list *timer = &wd->timer; + + wd->dev = dev; + wd->tsk = current; + + init_timer_on_stack(timer); + /* use same timeout value for both suspend and resume */ + timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_TIMEOUT; + timer->function = dpm_watchdog_handler; + timer->data = (unsigned long)wd; + add_timer(timer); +} + +/** + * dpm_watchdog_clear - Disable suspend/resume watchdog. + * @wd: Watchdog to disable. + */ +static void dpm_watchdog_clear(struct dpm_watchdog *wd) +{ + struct timer_list *timer = &wd->timer; + + del_timer_sync(timer); + destroy_timer_on_stack(timer); +} +#else +#define DECLARE_DPM_WATCHDOG_ON_STACK(wd) +#define dpm_watchdog_set(x, y) +#define dpm_watchdog_clear(x) +#endif + /*------------------------- Resume routines -------------------------*/ /** @@ -576,6 +643,7 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) pm_callback_t callback = NULL; char *info = NULL; int error = 0; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); TRACE_DEVICE(dev); TRACE_RESUME(0); @@ -584,6 +652,7 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) goto Complete; dpm_wait(dev->parent, async); + dpm_watchdog_set(&wd, dev); device_lock(dev); /* @@ -642,6 +711,7 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) Unlock: device_unlock(dev); + dpm_watchdog_clear(&wd); Complete: complete_all(&dev->power.completion); @@ -1060,6 +1130,7 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) pm_callback_t callback = NULL; char *info = NULL; int error = 0; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); dpm_wait_for_children(dev, async); @@ -1083,6 +1154,7 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) if (dev->power.syscore) goto Complete; + dpm_watchdog_set(&wd, dev); device_lock(dev); if (dev->pm_domain) { @@ -1139,6 +1211,7 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) } device_unlock(dev); + dpm_watchdog_clear(&wd); Complete: complete_all(&dev->power.completion); diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index d444c4e..2fac9cc 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -178,6 +178,22 @@ config PM_SLEEP_DEBUG def_bool y depends on PM_DEBUG && PM_SLEEP +config DPM_WATCHDOG + bool "Device suspend/resume watchdog" + depends on PM_DEBUG && PSTORE + ---help--- + Sets up a watchdog timer to capture drivers that are + locked up attempting to suspend/resume a device. + A detected lockup causes system panic with message + captured in pstore device for inspection in subsequent + boot session. + +config DPM_WATCHDOG_TIMEOUT + int "Watchdog timeout in seconds" + range 1 120 + default 12 + depends on DPM_WATCHDOG + config PM_TRACE bool help diff --git a/kernel/power/user.c b/kernel/power/user.c index 957f061..2485027 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -36,9 +36,9 @@ static struct snapshot_data { struct snapshot_handle handle; int swap; int mode; - char frozen; - char ready; - char platform_support; + bool frozen; + bool ready; + bool platform_support; bool free_bitmaps; } snapshot_state; @@ -93,9 +93,9 @@ static int snapshot_open(struct inode *inode, struct file *filp) if (error) atomic_inc(&snapshot_device_available); - data->frozen = 0; - data->ready = 0; - data->platform_support = 0; + data->frozen = false; + data->ready = false; + data->platform_support = false; Unlock: unlock_system_sleep(); @@ -229,7 +229,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, if (error) thaw_processes(); else - data->frozen = 1; + data->frozen = true; break; @@ -240,7 +240,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, free_basic_memory_bitmaps(); data->free_bitmaps = false; thaw_processes(); - data->frozen = 0; + data->frozen = false; break; case SNAPSHOT_CREATE_IMAGE: @@ -270,7 +270,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, case SNAPSHOT_FREE: swsusp_free(); memset(&data->handle, 0, sizeof(struct snapshot_handle)); - data->ready = 0; + data->ready = false; /* * It is necessary to thaw kernel threads here, because * SNAPSHOT_CREATE_IMAGE may be invoked directly after @@ -334,7 +334,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, * PM_HIBERNATION_PREPARE */ error = suspend_devices_and_enter(PM_SUSPEND_MEM); - data->ready = 0; + data->ready = false; break; case SNAPSHOT_PLATFORM_SUPPORT: |
