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. From: Chris Wilson <[email protected]> Subject: include/linux/bitops.h: introduce BITS_PER_TYPE net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the macro to bitops.h, alongside BITS_PER_BYTE, for wider usage. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Chris Wilson <[email protected]> Reviewed-by: Jani Nikula <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Andy Gospodarek <[email protected]> Cc: David S. Miller <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Signed-off-by: Andrew Morton <[email protected]> --- include/linux/bitops.h | 3 ++- include/linux/net_dim.h | 1 - 2 files changed, 2 insertions(+), 2 deletions(-) diff -puN include/linux/bitops.h~bitops-introduce-bits_per_type include/linux/bitops.h --- a/include/linux/bitops.h~bitops-introduce-bits_per_type +++ a/include/linux/bitops.h @@ -11,7 +11,8 @@ #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)) +#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE) +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long)) #endif /* diff -puN include/linux/net_dim.h~bitops-introduce-bits_per_type include/linux/net_dim.h --- a/include/linux/net_dim.h~bitops-introduce-bits_per_type +++ a/include/linux/net_dim.h @@ -363,7 +363,6 @@ static inline void net_dim_sample(u16 ev } #define NET_DIM_NEVENTS 64 -#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE) #define BIT_GAP(bits, end, start) ((((end) - (start)) + BIT_ULL(bits)) & (BIT_ULL(bits) - 1)) static inline void net_dim_calc_stats(struct net_dim_sample *start, _
