Re: RFC: Ideal Adaptive Spinning Conditions

From: john cooper
Date: Sat Apr 03 2010 - 14:11:47 EST


Darren Hart wrote:
> Right, and I'm looking to provide some kernel assistance for userspace
> spinlocks here, and am targeting short lived critical sections as well.

What did you have in mind beyond existing mechanisms
which address sibling contention?

One scenario which AFAICT isn't yet addressed is that
of a userspace spin lock holder taking a scheduling
preemption which may result in other threads piling up
on the lock orders of magnitude beyond normal wait times,
until the lock holder is rescheduled.

-john

--
john.cooper@xxxxxxxxxxxxxxxxxx
--
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/