reiserfs: use hweight_long()

Use hweight_long() to count free bits in the bitmap.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/reiserfs/bitmap.c

@@ -1222,15 +1222,11 @@ void reiserfs_cache_bitmap_metadata(struct super_block *sb,
 	info->free_count = 0;
 
 	while (--cur >= (unsigned long *)bh->b_data) {
-		int i;
-
 		/* 0 and ~0 are special, we can optimize for them */
 		if (*cur == 0)
 			info->free_count += BITS_PER_LONG;
 		else if (*cur != ~0L)	/* A mix, investigate */
-			for (i = BITS_PER_LONG - 1; i >= 0; i--)
-				if (!reiserfs_test_le_bit(i, cur))
-					info->free_count++;
+			info->free_count += BITS_PER_LONG - hweight_long(*cur);
 	}
 }