From: Chunguang Xu <brookxu@xxxxxxxxxxx>
The code of mb_find_order_for_block is a bit obscure, but we can
simplify it with mb_find_buddy(), make the code more concise.
Signed-off-by: Chunguang Xu <brookxu@xxxxxxxxxxx>
Reviewed-by: Andreas Dilger <adilger@xxxxxxxxx>
---
fs/ext4/mballoc.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 5b74555..29dfeb04 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1289,22 +1289,18 @@ static void ext4_mb_unload_buddy(struct ext4_buddy *e4b)
static int mb_find_order_for_block(struct ext4_buddy *e4b, int block)
{
- int order = 1;
- int bb_incr = 1 << (e4b->bd_blkbits - 1);
+ int order = 1, max;
void *bb;
BUG_ON(e4b->bd_bitmap == e4b->bd_buddy);
BUG_ON(block >= (1 << (e4b->bd_blkbits + 3)));
- bb = e4b->bd_buddy;
while (order <= e4b->bd_blkbits + 1) {
- block = block >> 1;
- if (!mb_test_bit(block, bb)) {
+ bb = mb_find_buddy(e4b, order, &max);
+ if (!mb_test_bit(block >> order, bb)) {
/* this block is part of buddy of order 'order' */
return order;
}
- bb += bb_incr;
- bb_incr >>= 1;
order++;
}
return 0;
--
1.8.3.1
