Commit c1f5204e authored by Yury Norov's avatar Yury Norov Committed by Paolo Abeni
Browse files

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: default avatarYury Norov <yury.norov@gmail.com>
Reviewed-by: default avatarJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 3723b56d

include/linux/bitmap.h

+12 −0
Original line number Diff line number Diff line
@@ -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)

{

include/linux/cpumask.h

+13 −0
Original line number Diff line number Diff line
@@ -719,6 +719,19 @@ static inline unsigned int cpumask_weight_and(const struct cpumask *srcp1, 
	return bitmap_weight_and(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);

}



/**

 * cpumask_weight_andnot - Count of bits in (*srcp1 & ~*srcp2)

 * @srcp1: the cpumask to count bits (< nr_cpu_ids) in.

 * @srcp2: the cpumask to count bits (< nr_cpu_ids) in.

 *

 * Return: count of bits set in both *srcp1 and *srcp2

 */

static inline unsigned int cpumask_weight_andnot(const struct cpumask *srcp1,

						const struct cpumask *srcp2)

{

	return bitmap_weight_andnot(cpumask_bits(srcp1), cpumask_bits(srcp2), small_cpumask_bits);

}



/**

 * cpumask_shift_right - *dstp = *srcp >> n

 * @dstp: the cpumask result

lib/bitmap.c

+7 −0
Original line number Diff line number Diff line
@@ -348,6 +348,13 @@ unsigned int __bitmap_weight_and(const unsigned long *bitmap1, 
}

EXPORT_SYMBOL(__bitmap_weight_and);



unsigned int __bitmap_weight_andnot(const unsigned long *bitmap1,

				const unsigned long *bitmap2, unsigned int bits)

{

	return BITMAP_WEIGHT(bitmap1[idx] & ~bitmap2[idx], bits);

}

EXPORT_SYMBOL(__bitmap_weight_andnot);



void __bitmap_set(unsigned long *map, unsigned int start, int len)

{

	unsigned long *p = map + BIT_WORD(start);