On Mon, 9 Jul 2018 12:32:51 +0100 Will Deacon <[email protected]> wrote:
> Hi Andrew, > > On Fri, Jul 06, 2018 at 05:30:49PM -0700, Andrew Morton wrote: > > On Tue, 19 Jun 2018 13:53:08 +0100 Will Deacon <[email protected]> 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>. Also, all these macros no longer `#ifdef __KERNEL__' protection, which wasn't mentioned in the changelog. Deliberate?
