On Fri, Jan 29, 2021 at 1:11 PM Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote: > > 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. Lower case for generic macro kind of breaking the rules. Behaviour has changed too. Before it was: 0 < VAL <= 32 Now it's 0 <= VAL < 32 Which is better for generic macro. So changing the name looks reasonable to me. > ... > > > --- 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?! git send-email wrong_dir/000* Will resubmit today later. > ... > > > 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
