Hi again, Andrew, On Mon, Jul 09, 2018 at 03:10:06PM -0700, Andrew Morton wrote: > On Mon, 9 Jul 2018 12:32:51 +0100 Will Deacon <will.dea...@arm.com> wrote: > > On Fri, Jul 06, 2018 at 05:30:49PM -0700, Andrew Morton wrote: > > > On Tue, 19 Jun 2018 13:53:08 +0100 Will Deacon <will.dea...@arm.com> > > > wrote: > > > > > > > In preparation for implementing the asm-generic atomic bitops in terms > > > > of atomic_long_*, we need to prevent asm/atomic.h implementations from > > > > pulling in linux/bitops.h. A common reason for this include is for the > > > > BITS_PER_BYTE definition, so move this and some other BIT() and masking > > > > macros into a new header file, linux/bits.h > > > > > > > > --- a/include/linux/bitops.h > > > > +++ b/include/linux/bitops.h > > > > @@ -2,29 +2,9 @@ > > > > #ifndef _LINUX_BITOPS_H > > > > #define _LINUX_BITOPS_H > > > > #include <asm/types.h> > > > > +#include <linux/bits.h> > > > > > > > > -#ifdef __KERNEL__ > > > > -#define BIT(nr) (1UL << (nr)) > > > > -#define BIT_ULL(nr) (1ULL << (nr)) > > > > -#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) > > > > -#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) > > > > -#define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG)) > > > > -#define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG) > > > > -#define BITS_PER_BYTE 8 > > > > #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * > > > > sizeof(long)) > > > > -#endif > > > > > > Why does it leave BITS_TO_LONGS() in place? > > > > > > That becomes unfortunate with Chris's patch, so I'm moving > > > BITS_TO_LONGS() into bits.h. > > > > The reason I avoided that was because it would pull in the dreaded > > kernel.h for DIV_ROUND_UP, and then we're back to circular include hell :( > > > > Well we should comment that so every reader doesn't wonder what I > wondered. > > Refactoring works well. I suppose DIV_ROUND_UP and friends await a new > <arithmacros.h>.
Yes; pulling apart kernel.h would certainly help solve some of the fragility here. > Also, all these macros no longer `#ifdef __KERNEL__' protection, which > wasn't mentioned in the changelog. Deliberate? Yes, these aren't under uapi/ so I dropped the guards now that they're not needed (my understanding is that they're only there because of the way the uapi split was originally scripted). I can also confirm that the generated user headers match exactly with and without my changes. Will
