On Fri, Jan 29, 2021 at 10:49 PM Yury Norov <yury.norov@xxxxxxxxx> wrote: > > Many algorithms become simplier if they are passed with relatively small simpler > input values. One example is bitmap operations when the whole bitmap fits > into one word. To implement such simplifications, linux/bitmap.h declares > small_const_nbits() macro. > > Other subsystems may also benefit from optimizations of this sort, like > find_bit API in the following patches. So it looks helpful to generalize > the macro and extend it's visibility. > It should probably go to linux/kernel.h, but doing that creates circular > dependencies. So put it in asm-generic/bitsperlong.h. No, no, please leave kernel.h alone. It's already quite a mess. And this shouldn't be in the commit message either. ... > - if (small_const_nbits(nbits)) > + if (SMALL_CONST(nbits - 1)) Not sure if we need to rename it. ... > --- a/include/linux/bits.h > +++ b/include/linux/bits.h > @@ -37,7 +37,7 @@ > #define GENMASK(h, l) \ > (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l)) > > -#define BITS_FIRST(nr) GENMASK(nr), 0) > +#define BITS_FIRST(nr) GENMASK((nr), 0) How come?! ... > diff --git a/tools/include/asm-generic/bitsperlong.h b/tools/include/asm-generic/bitsperlong.h > index 8f2283052333..432d272baf27 100644 > --- a/tools/include/asm-generic/bitsperlong.h > +++ b/tools/include/asm-generic/bitsperlong.h I think a tools update would be better to have in a separate patch. -- With Best Regards, Andy Shevchenko
