lib: bitmap: make nbits parameter of bitmap_weight unsigned

The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative.  Since no-one passes a negative
bit-count, this shouldn't affect the semantics.

I didn't change the return type, since that might change the semantics
of some expression containing a call to bitmap_weight(). Certainly an
int is capable of holding the result.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/lib/bitmap.c b/lib/bitmap.c
index c9bff5379795..f69435c23f9c 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -259,9 +259,10 @@ int __bitmap_subset(const unsigned long *bitmap1,
 }
 EXPORT_SYMBOL(__bitmap_subset);
 
-int __bitmap_weight(const unsigned long *bitmap, int bits)
+int __bitmap_weight(const unsigned long *bitmap, unsigned int bits)
 {
-        int k, w = 0, lim = bits/BITS_PER_LONG;
+        unsigned int k, lim = bits/BITS_PER_LONG;
+        int w = 0;
 
         for (k = 0; k < lim; k++)
                 w += hweight_long(bitmap[k]);