On Tue, Oct 08, 2013 at 02:12:18PM -0700, Paul E. McKenney wrote: > On Tue, Oct 08, 2013 at 10:34:28PM +0200, Frederic Weisbecker wrote: > > So I wonder, do we want to continue to allow this nesting? I remember that > > DYNTICK_TASK_NEST_* > > stuff is there to protects against non finishing interrupts on some archs > > (I also remember that > > this, or at least a practical scenario for this, was hard to really define > > though :o) > > But then wouldn't it involve other kind of scenario like this? > > > > rcu_irq_enter() > > rcu_eqs_enter() > > rcu_eqs_exit() > > ... > > > > Anyway, that's just random thougths on further simplifications, in any > > case, this > > patch looks good. > > Yep, if no task-level nesting is ever required, things could be a bit > simpler. I would be a bit slow about making such a change, though. > After all, the need to deal with Hotel California interrupts means that > handling nesting isn't that big of a deal comparatively. ;-)
Right, well ideally it would be even best to fix the corner case(s) if there aren't that many of them. I mean calling rcu_irq_exit() from the end of those half interrupts I guess. It would make it much simpler than this complicated nesting handled on the core code. But I agree there is a bit of unknown out there, so yeah lets be prudent :) > May I add your Reviewed-by? Sure, thanks! -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
