On Fri, Mar 23, 2007 at 11:04:18AM +0100, Ingo Molnar wrote: >> isnt this patented by MS? (which might not worry you SuSE/Novell guys, >> but it might be a worry for the rest of the world ;-)
On Fri, Mar 23, 2007 at 11:32:44AM +0100, Nick Piggin wrote: > Hmm, it looks like they have implemented a system where the spinning > cpu sleeps on a per-CPU variable rather than the lock itself, and > the releasing cpu writes to that variable to wake it. They do this > so that spinners don't continually perform exclusive->shared > transitions on the lock cacheline. They call these things queued > spinlocks. They don't seem to be very patent worthy either, but > maybe it is what you're thinking of? Those exclusive-to-shared transitions are among the cacheline transfers typically accounted to the algorithms in their complexity analyses. -- wli - 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/