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| author | Yury Norov <yury.norov@gmail.com> | 2024-01-28 22:21:04 -0800 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2024-02-01 13:06:40 +0100 |
| commit | c1f5204efcbcced83f67f12fa8f1a7f5f244fb87 (patch) | |
| tree | 4cf65b8c65041554ba6cdccd75ace4b62f247028 /include/linux/bitmap.h | |
| parent | 3723b56d6f73f7c8c3b521a80556f129830f6fb9 (diff) | |
| download | linux-stable-c1f5204efcbcced83f67f12fa8f1a7f5f244fb87.tar.gz linux-stable-c1f5204efcbcced83f67f12fa8f1a7f5f244fb87.tar.bz2 linux-stable-c1f5204efcbcced83f67f12fa8f1a7f5f244fb87.zip | |
cpumask: add cpumask_weight_andnot()
Similarly to cpumask_weight_and(), cpumask_weight_andnot() is a handy
helper that may help to avoid creating an intermediate mask just to
calculate number of bits that set in a 1st given mask, and clear in 2nd
one.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'include/linux/bitmap.h')
| -rw-r--r-- | include/linux/bitmap.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 99451431e4d6..5814e9ee40ba 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -54,6 +54,7 @@ struct device; * bitmap_full(src, nbits) Are all bits set in *src? * bitmap_weight(src, nbits) Hamming Weight: number set bits * bitmap_weight_and(src1, src2, nbits) Hamming Weight of and'ed bitmap + * bitmap_weight_andnot(src1, src2, nbits) Hamming Weight of andnot'ed bitmap * bitmap_set(dst, pos, nbits) Set specified bit area * bitmap_clear(dst, pos, nbits) Clear specified bit area * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area @@ -169,6 +170,8 @@ bool __bitmap_subset(const unsigned long *bitmap1, unsigned int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits); unsigned int __bitmap_weight_and(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int nbits); +unsigned int __bitmap_weight_andnot(const unsigned long *bitmap1, + const unsigned long *bitmap2, unsigned int nbits); void __bitmap_set(unsigned long *map, unsigned int start, int len); void __bitmap_clear(unsigned long *map, unsigned int start, int len); @@ -425,6 +428,15 @@ unsigned long bitmap_weight_and(const unsigned long *src1, return __bitmap_weight_and(src1, src2, nbits); } +static __always_inline +unsigned long bitmap_weight_andnot(const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) + return hweight_long(*src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)); + return __bitmap_weight_andnot(src1, src2, nbits); +} + static __always_inline void bitmap_set(unsigned long *map, unsigned int start, unsigned int nbits) { |