Re: [PATCH 05/14] hrtimer: Fix invalid wakeup in do_nanosleep
From: Thomas Gleixner
Date: Thu Sep 12 2013 - 09:34:31 EST
On Thu, 29 Aug 2013, Libin wrote:
> If thread is preempted before calling set_current_state(TASK_INTERRUPTIBLE),
> and the other thread set the condition followed with wake_up_process. After
> that when this thread is re-scheduled, calling set_current_state to set itself
> as state TASK_INTERRUPTIBLE, if it is preempted again after that and before
> __set_current_state(TASK_RUNNING), it triggers the invalid wakeup problem.
do_nanosleep() is only called from sys_nanosleep() and
sys_clock_nanosleep() user space interfaces.
So the task is not going to be woken up by some magic other thread
except by a signal. The latter is handled by the scheduler which will
return with state running. So what kind of problem are you trying to
solve?
Thanks,
tglx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/