Re: [RFC][PATCH 3/7] sched: Allow balance callbacks for check_class_changed()

[Peter Zijlstra]

On Tue, Jun 02, 2015 at 07:27:19PM +0300, Kirill Tkhai wrote:
> > +	 * task_dead_dl() will cancel our timer if we happen to die while
> > +	 * its still pending.
> 
> task_dead_dl() is called for tasks of deadline class only. So if we do that,
> the timer may be executed after final task's dead.

Indeed; sleep deprived brain misses the obvious :/

I can't seem to come up with anything much better than pulling that
hrtimer_cancel() into finish_task_switch(), however sad that is.

Something like:

  for_each_class(class) {
	if (class->task_dead)
		class->task_dead(prev);
  }

Would be nicest, but will slow down the common case. And a callback list
has the downside of having to preallocate entries for every task,
causing mostly pointless memory overhead.


--
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/