On Mon, 24 Jul 2017 23:46:44 +1000 Michael Ellerman <m...@ellerman.id.au> wrote:
> 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. Not further special-casing, but just casing it based on NR_CPUS rather than BOOK3S. Thanks, Nick
