[PATCH v3 5/6] lib/bitmap: remove bitmap_ord_to_pos

From: Yury Norov
Date: Sat Sep 17 2022 - 23:08:05 EST


Now that we have find_nth_bit(), we can drop bitmap_ord_to_pos().

Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx>
---
include/linux/bitmap.h | 1 -
include/linux/nodemask.h | 3 +--
lib/bitmap.c | 36 +++---------------------------------
3 files changed, 4 insertions(+), 36 deletions(-)

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index b2aef45af0db..7d6d73b78147 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -225,7 +225,6 @@ void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int n
#else
#define bitmap_copy_le bitmap_copy
#endif
-unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
int bitmap_print_to_pagebuf(bool list, char *buf,
const unsigned long *maskp, int nmaskbits);

diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h
index 4b71a96190a8..0c45fb066caa 100644
--- a/include/linux/nodemask.h
+++ b/include/linux/nodemask.h
@@ -508,8 +508,7 @@ static inline int node_random(const nodemask_t *maskp)

w = nodes_weight(*maskp);
if (w)
- bit = bitmap_ord_to_pos(maskp->bits,
- get_random_int() % w, MAX_NUMNODES);
+ bit = find_nth_bit(maskp->bits, MAX_NUMNODES, get_random_int() % w);
return bit;
#else
return 0;
diff --git a/lib/bitmap.c b/lib/bitmap.c
index 3fc2e338ec30..1c81413c51f8 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -968,36 +968,6 @@ static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigne
return bitmap_weight(buf, pos);
}

-/**
- * bitmap_ord_to_pos - find position of n-th set bit in bitmap
- * @buf: pointer to bitmap
- * @ord: ordinal bit position (n-th set bit, n >= 0)
- * @nbits: number of valid bit positions in @buf
- *
- * Map the ordinal offset of bit @ord in @buf to its position in @buf.
- * Value of @ord should be in range 0 <= @ord < weight(buf). If @ord
- * >= weight(buf), returns @nbits.
- *
- * If for example, just bits 4 through 7 are set in @buf, then @ord
- * values 0 through 3 will get mapped to 4 through 7, respectively,
- * and all other @ord values returns @nbits. When @ord value 3
- * gets mapped to (returns) @pos value 7 in this example, that means
- * that the 3rd set bit (starting with 0th) is at position 7 in @buf.
- *
- * The bit positions 0 through @nbits-1 are valid positions in @buf.
- */
-unsigned int bitmap_ord_to_pos(const unsigned long *buf, unsigned int ord, unsigned int nbits)
-{
- unsigned int pos;
-
- for (pos = find_first_bit(buf, nbits);
- pos < nbits && ord;
- pos = find_next_bit(buf, nbits, pos + 1))
- ord--;
-
- return pos;
-}
-
/**
* bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap
* @dst: remapped result
@@ -1047,7 +1017,7 @@ void bitmap_remap(unsigned long *dst, const unsigned long *src,
if (n < 0 || w == 0)
set_bit(oldbit, dst); /* identity map */
else
- set_bit(bitmap_ord_to_pos(new, n % w, nbits), dst);
+ set_bit(find_nth_bit(new, nbits, n % w), dst);
}
}
EXPORT_SYMBOL(bitmap_remap);
@@ -1086,7 +1056,7 @@ int bitmap_bitremap(int oldbit, const unsigned long *old,
if (n < 0 || w == 0)
return oldbit;
else
- return bitmap_ord_to_pos(new, n % w, bits);
+ return find_nth_bit(new, bits, n % w);
}
EXPORT_SYMBOL(bitmap_bitremap);

@@ -1210,7 +1180,7 @@ void bitmap_onto(unsigned long *dst, const unsigned long *orig,
* The following code is a more efficient, but less
* obvious, equivalent to the loop:
* for (m = 0; m < bitmap_weight(relmap, bits); m++) {
- * n = bitmap_ord_to_pos(orig, m, bits);
+ * n = find_nth_bit(orig, bits, m);
* if (test_bit(m, orig))
* set_bit(n, dst);
* }
--
2.34.1