Nicholas Piggin <npig...@gmail.com> writes: > On Mon, 24 Jul 2017 14:28:02 +1000 > Benjamin Herrenschmidt <b...@kernel.crashing.org> wrote: > >> Instead of comparing the whole CPU mask every time, let's >> keep a counter of how many bits are set in the mask. Thus >> testing for a local mm only requires testing if that counter >> is 1 and the current CPU bit is set in the mask. ... > > Also does it make sense to define it based on NR_CPUS > BITS_PER_LONG? > If it's <= then it should be similar load and compare, no?
Do we make a machine with that few CPUs? ;) I don't think it's worth special casing, all the distros run with much much larger NR_CPUs than that. cheers