On 08/16, Dan Aloni wrote:
>
> On Sun, Jul 01, 2007 at 07:37:49PM +0400, Oleg Nesterov wrote:
> > I don't know how to test this patch, the ack/nack from maintainer is wanted.
> > 
> > flush_scheduled_work() is evil and should be avoided. Change tty_set_ldisc()
> > and release_dev() to use cancel_delayed_work_sync/cancel_work_sync.
> > 
> > I am not sure we really need to call do_tty_hangup() when cancel_work_sync()
> > returns true, but this matches the current behaviour.
> 
> I also noticed this problem recently with 2.6.22, on a 2-CPU box where there 
> was one SCHED_RR userspace process stuck in a busy loop. The box was 
> completely 
> responsive but had this annoyance where all tty closings were stuck in 
> flush_scheduled_work(). It's especially noticable when you ssh to the machine
> and then try to log out.

cancel_work_sync(work) can hang too if some SCHED_RR userspace process does not
relinquish CPU, but the probability is much lower (it should preempt work->func
of that work_struct).

see also http://marc.info/?l=linux-kernel&m=118115098120503.

Oleg.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to