lib: bitmap: make the start index of bitmap_set unsigned

The compiler can generate slightly smaller and simpler code when it
knows that "start" is non-negative.

Also, use the names "start" and "len" for the two parameters in both
header file and implementation, instead of the previous mix.

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>

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index 64b0ebe9f9a8033e0264f2ea5d5143c89c0ac124..ad2c67d3583e9f931eb136798d4ce552a9f7f4dd 100644 (file)
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -112,7 +112,7 @@ extern int __bitmap_subset(const unsigned long *bitmap1,
                        const unsigned long *bitmap2, unsigned int nbits);
 extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
 
-extern void bitmap_set(unsigned long *map, int i, int len);
+extern void bitmap_set(unsigned long *map, unsigned int start, int len);
 extern void bitmap_clear(unsigned long *map, int start, int nr);
 extern unsigned long bitmap_find_next_zero_area(unsigned long *map,
                                         unsigned long size,

diff --git a/lib/bitmap.c b/lib/bitmap.c
index f69435c23f9c8278e99e774c8f0410a10a75f457..2a3a92fc33557c5be8d717a429de63cb86ea852c 100644 (file)
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -274,21 +274,21 @@ int __bitmap_weight(const unsigned long *bitmap, unsigned int bits)
 }
 EXPORT_SYMBOL(__bitmap_weight);
 
-void bitmap_set(unsigned long *map, int start, int nr)
+void bitmap_set(unsigned long *map, unsigned int start, int len)
 {
        unsigned long *p = map + BIT_WORD(start);
-       const int size = start + nr;
+       const unsigned int size = start + len;
        int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
        unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
 
-       while (nr - bits_to_set >= 0) {
+       while (len - bits_to_set >= 0) {
                *p |= mask_to_set;
-               nr -= bits_to_set;
+               len -= bits_to_set;
                bits_to_set = BITS_PER_LONG;
                mask_to_set = ~0UL;
                p++;
        }
-       if (nr) {
+       if (len) {
                mask_to_set &= BITMAP_LAST_WORD_MASK(size);
                *p |= mask_to_set;
        }