diff options
Diffstat (limited to 'include/linux/bitmap.h')
| -rw-r--r-- | include/linux/bitmap.h | 25 |
1 files changed, 21 insertions, 4 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 262b6596eca5..b0395e4ccf90 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -23,7 +23,7 @@ struct device; * * Function implementations generic to all architectures are in * lib/bitmap.c. Functions implementations that are architecture - * specific are in various include/asm-<arch>/bitops.h headers + * specific are in various arch/<arch>/include/asm/bitops.h headers * and other arch/<arch> specific files. * * See lib/bitmap.c for more details. @@ -45,6 +45,7 @@ struct device; * bitmap_copy(dst, src, nbits) *dst = *src * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2 * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2 + * bitmap_weighted_or(dst, src1, src2, nbits) *dst = *src1 | *src2. Returns Hamming Weight of dst * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2 * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2) * bitmap_complement(dst, src, nbits) *dst = ~(*src) @@ -165,6 +166,8 @@ bool __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); +unsigned int __bitmap_weighted_or(unsigned long *dst, const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); bool __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, @@ -338,6 +341,18 @@ void bitmap_or(unsigned long *dst, const unsigned long *src1, } static __always_inline +unsigned int bitmap_weighted_or(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) { + *dst = *src1 | *src2; + return hweight_long(*dst & BITMAP_LAST_WORD_MASK(nbits)); + } else { + return __bitmap_weighted_or(dst, src1, src2, nbits); + } +} + +static __always_inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, const unsigned long *src2, unsigned int nbits) { @@ -560,9 +575,9 @@ void bitmap_replace(unsigned long *dst, * ...0..11...0..10 * dst: 0000001100000010 * - * A relationship exists between bitmap_scatter() and bitmap_gather(). + * A relationship exists between bitmap_scatter() and bitmap_gather(). See + * bitmap_gather() for the bitmap gather detailed operations. TL;DR: * bitmap_gather() can be seen as the 'reverse' bitmap_scatter() operation. - * See bitmap_scatter() for details related to this relationship. */ static __always_inline void bitmap_scatter(unsigned long *dst, const unsigned long *src, @@ -608,7 +623,9 @@ void bitmap_scatter(unsigned long *dst, const unsigned long *src, * dst: 0000000000011010 * * A relationship exists between bitmap_gather() and bitmap_scatter(). See - * bitmap_scatter() for the bitmap scatter detailed operations. + * bitmap_scatter() for the bitmap scatter detailed operations. TL;DR: + * bitmap_scatter() can be seen as the 'reverse' bitmap_gather() operation. + * * Suppose scattered computed using bitmap_scatter(scattered, src, mask, n). * The operation bitmap_gather(result, scattered, mask, n) leads to a result * equal or equivalent to src. |