On Mon, Oct 07, 2013 at 10:05:16PM -0300, Marcelo Tosatti wrote: > In certain occasions it is possible for a hung task detector > positive to be false: continuation from a paused VM, for example. > > Add a method to reset detection, similar as is done > with other kernel watchdogs. This makes sense to me. Should we throw the 'reset_hung_task_detector' in include/linux/sched.h like some of the other watchdog functions? Or is having a small hung_task.h file like this fine? Cheers, Don > > Signed-off-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx> > > Index: kvm/kernel/hung_task.c > =================================================================== > --- kvm.orig/kernel/hung_task.c > +++ kvm/kernel/hung_task.c > @@ -203,6 +203,14 @@ int proc_dohung_task_timeout_secs(struct > return ret; > } > > +static atomic_t reset_hung_task = ATOMIC_INIT(0); > + > +void reset_hung_task_detector(void) > +{ > + atomic_set(&reset_hung_task, 1); > +} > +EXPORT_SYMBOL_GPL(reset_hung_task_detector); > + > /* > * kthread which checks for tasks stuck in D state > */ > @@ -216,6 +224,9 @@ static int watchdog(void *dummy) > while (schedule_timeout_interruptible(timeout_jiffies(timeout))) > timeout = sysctl_hung_task_timeout_secs; > > + if (atomic_xchg(&reset_hung_task, 0)) > + continue; > + > check_hung_uninterruptible_tasks(timeout); > } > > Index: kvm/include/linux/hung_task.h > =================================================================== > --- /dev/null > +++ kvm/include/linux/hung_task.h > @@ -0,0 +1,15 @@ > +/* > + * linux/include/linux/hung_task.h > + */ > +#ifndef LINUX_HUNG_TASK_H > +#define LINUX_HUNG_TASK_H > + > +#ifdef CONFIG_DETECT_HUNG_TASK > +void reset_hung_task_detector(void); > +#else > +static inline void reset_hung_task_detector(void) > +{ > +} > +#endif > + > +#endif > > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html