2011-02-06 04:27:19

by Coly Li

Subject: [PATCH 1/5] mballoc: code cleanup in mb_find_buddy()

Current code calculate max no matter whether order is zero, it's
unnecessary. This cleanup patch sets max to "1 << (e4b->bd_blkbits
+ 3)" only when order == 0.

Signed-off-by: Coly Li <[email protected]>
Cc: Alex Tomas <[email protected]>
Cc: Theodore Tso <[email protected]>
---
fs/ext4/mballoc.c | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 851f49b..d5b372c 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -427,9 +427,10 @@ static void *mb_find_buddy(struct ext4_buddy *e4b, int order, int *max)
}

/* at order 0 we see each particular block */
- *max = 1 << (e4b->bd_blkbits + 3);
- if (order == 0)
+ if (order == 0) {
+ *max = 1 << (e4b->bd_blkbits + 3);
return EXT4_MB_BITMAP(e4b);
+ }

bb = EXT4_MB_BUDDY(e4b) + EXT4_SB(e4b->bd_sb)->s_mb_offsets[order];
*max = EXT4_SB(e4b->bd_sb)->s_mb_maxs[order];
--
1.7.3.4

2011-02-24 19:06:49

by Theodore Ts'o

Subject: Re: [PATCH 1/5] mballoc: code cleanup in mb_find_buddy()

On Sun, Feb 06, 2011 at 12:53:44PM +0800, Coly Li wrote:
> Current code calculate max no matter whether order is zero, it's
> unnecessary. This cleanup patch sets max to "1 << (e4b->bd_blkbits
> + 3)" only when order == 0.
>
> Signed-off-by: Coly Li <[email protected]>
> Cc: Alex Tomas <[email protected]>
> Cc: Theodore Tso <[email protected]>

Added to the ext4 patch queue, thanks!

- Ted