diff options
| author | San Mehat <san@google.com> | 2009-08-13 09:40:42 -0700 |
|---|---|---|
| committer | Dan Willemsen <dwillemsen@nvidia.com> | 2011-11-30 21:38:12 -0800 |
| commit | 5289f2b5e494ee01f6a2b914b8075f1eb33e5721 (patch) | |
| tree | 9921ab1150324146416350567ce1586413d4a6da /drivers | |
| parent | d4076ae3b7eff09f9d4c1f4193572e27db59dbd9 (diff) | |
drivers: power: Add watchdog timer to catch drivers which lockup during suspend.
Rather than hard-lock the kernel, we now BUG() when a driver takes
> 3 seconds to suspend. If the underlying platform supports panic dumps,
then the data can be collected for debug.
Signed-off-by: San Mehat <san@google.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/base/power/main.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index a85459126bc6..5e576466a189 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -27,6 +27,7 @@ #include <linux/sched.h> #include <linux/async.h> #include <linux/suspend.h> +#include <linux/timer.h> #include "../base.h" #include "power.h" @@ -49,6 +50,9 @@ LIST_HEAD(dpm_noirq_list); static DEFINE_MUTEX(dpm_list_mtx); static pm_message_t pm_transition; +static void dpm_drv_timeout(unsigned long data); +static DEFINE_TIMER(dpm_drv_wd, dpm_drv_timeout, 0, 0); + static int async_error; /** @@ -592,6 +596,45 @@ static bool is_async(struct device *dev) } /** + * dpm_drv_timeout - Driver suspend / resume watchdog handler + * @data: struct device which timed out + * + * Called when a driver has timed out suspending or resuming. + * There's not much we can do here to recover so + * BUG() out for a crash-dump + * + */ +static void dpm_drv_timeout(unsigned long data) +{ + struct device *dev = (struct device *) data; + + printk(KERN_EMERG "**** DPM device timeout: %s (%s)\n", dev_name(dev), + (dev->driver ? dev->driver->name : "no driver")); + BUG(); +} + +/** + * dpm_drv_wdset - Sets up driver suspend/resume watchdog timer. + * @dev: struct device which we're guarding. + * + */ +static void dpm_drv_wdset(struct device *dev) +{ + dpm_drv_wd.data = (unsigned long) dev; + mod_timer(&dpm_drv_wd, jiffies + (HZ * 3)); +} + +/** + * dpm_drv_wdclr - clears driver suspend/resume watchdog timer. + * @dev: struct device which we're no longer guarding. + * + */ +static void dpm_drv_wdclr(struct device *dev) +{ + del_timer_sync(&dpm_drv_wd); +} + +/** * dpm_resume - Execute "resume" callbacks for non-sysdev devices. * @state: PM transition of the system being carried out. * @@ -962,7 +1005,9 @@ int dpm_suspend(pm_message_t state) get_device(dev); mutex_unlock(&dpm_list_mtx); + dpm_drv_wdset(dev); error = device_suspend(dev); + dpm_drv_wdclr(dev); mutex_lock(&dpm_list_mtx); if (error) { |