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bitmap: make bitmap_{get,set}_value8() use bitmap_{read,write}()

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Now that we have generic bitmap_read() and bitmap_write(), which are
inline and try to take care of non-bound-crossing and aligned cases
to keep them optimized, collapse bitmap_{get,set}_value8() into
simple wrappers around the former ones.
bloat-o-meter shows no difference in vmlinux and -2 bytes for
gpio-pca953x.ko, which says the optimization didn't suffer due to
that change. The converted helpers have the value width embedded
and always compile-time constant and that helps a lot.

Suggested-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alexander Lobakin 2024-03-27 16:23:50 +01:00 committed by David S. Miller
parent a37fbe666c
commit b44759705f
1 changed files with 5 additions and 33 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

38
include/linux/bitmap.h
View file

@ -727,39 +727,6 @@ static inline void bitmap_from_u64(unsigned long *dst, u64 mask)
bitmap_from_arr64(dst, &mask, 64); bitmap_from_arr64(dst, &mask, 64);
} }
/**
* bitmap_get_value8 - get an 8-bit value within a memory region
* @map: address to the bitmap memory region
* @start: bit offset of the 8-bit value; must be a multiple of 8
*
* Returns the 8-bit value located at the @start bit offset within the @src
* memory region.
*/
static inline unsigned long bitmap_get_value8(const unsigned long *map,
unsigned long start)
{
const size_t index = BIT_WORD(start);
const unsigned long offset = start % BITS_PER_LONG;
return (map[index] >> offset) & 0xFF;
}
/**
* bitmap_set_value8 - set an 8-bit value within a memory region
* @map: address to the bitmap memory region
* @value: the 8-bit value; values wider than 8 bits may clobber bitmap
* @start: bit offset of the 8-bit value; must be a multiple of 8
*/
static inline void bitmap_set_value8(unsigned long *map, unsigned long value,
unsigned long start)
{
const size_t index = BIT_WORD(start);
const unsigned long offset = start % BITS_PER_LONG;
map[index] &= ~(0xFFUL << offset);
map[index] |= value << offset;
}
/** /**
* bitmap_read - read a value of n-bits from the memory region * bitmap_read - read a value of n-bits from the memory region
* @map: address to the bitmap memory region * @map: address to the bitmap memory region
@ -833,6 +800,11 @@ static inline void bitmap_write(unsigned long *map, unsigned long value,
map[index + 1] |= (value >> space); map[index + 1] |= (value >> space);
} }
#define bitmap_get_value8(map, start) \
bitmap_read(map, start, BITS_PER_BYTE)
#define bitmap_set_value8(map, value, start) \
bitmap_write(map, value, start, BITS_PER_BYTE)
#endif /* __ASSEMBLY__ */ #endif /* __ASSEMBLY__ */
#endif /* __LINUX_BITMAP_H */ #endif /* __LINUX_BITMAP_H */