From: Charles Manning <cdhmanning@gmail.com>
Date: Sun, 5 Dec 2010 21:45:02 +0000 (+1300)
Subject: yaffs : Change bitmap counting function to use hweight8()
X-Git-Tag: linux-mainline-patchset-4~11^2
X-Git-Url: http://www.aleph1.co.uk/gitweb/?p=yaffs2.git;a=commitdiff_plain;h=7620f7d1207e72dc6b3c58bc452000b9ec82b57b

yaffs : Change bitmap counting function to use hweight8()

Better than shift counting.

Signed-off-by: Charles Manning <cdhmanning@gmail.com>
---

diff --git a/yaffs_bitmap.c b/yaffs_bitmap.c
index 5d1cfb2..b254266 100644
--- a/yaffs_bitmap.c
+++ b/yaffs_bitmap.c
@@ -90,15 +90,9 @@ int yaffs_count_chunk_bits(struct yaffs_dev *dev, int blk)
 	u8 *blk_bits = yaffs_block_bits(dev, blk);
 	int i;
 	int n = 0;
-	for (i = 0; i < dev->chunk_bit_stride; i++) {
-		u8 x = *blk_bits;
-		while (x) {
-			if (x & 1)
-				n++;
-			x >>= 1;
-		}
 
-		blk_bits++;
-	}
+	for (i = 0; i < dev->chunk_bit_stride; i++, blk_bits++)
+		n += hweight8(*blk_bits);
+
 	return n;
 }