On Wed, May 21, 2014 at 3:25 PM, Andi Kleen <a...@firstfloor.org> wrote: > > Seems like a lot of effort and risk to essentially only optimize in kernel > interrupt handlers.
The idea is that it might allow us to remove a bunch of scary nested NMI code as well as speeding things up. > > AFAIK the most interesting cases (like user page faults) are not > affected at all. Usually most workloads don't spend all that much time > in the kernel, so it won't help most interrupts. > > I suspect the only case that's really interesting here is interrupting > idle. Maybe it would be possible to do some fast path in this case only. > > However idle currently has so much overhead that I suspect that there > are lower hanging fruit elsewhere. I will gladly buy a meal or beverage for whomever fixes the ttwu stuff to stop sending IPIs to idle CPUs, which will help a lot. --Andy -- 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/
