From: Chao Yu <yuch...@huawei.com> Restructure struct seg_entry to eliminate holes in it, after that, in 32-bits machine, it reduces size from 32 bytes to 24 bytes; in 64-bits machine, it reduces size from 56 bytes to 40 bytes.
Signed-off-by: Chao Yu <yuch...@huawei.com> --- fs/f2fs/segment.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 975c33d..7a756ff 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -158,16 +158,17 @@ struct victim_sel_policy { }; struct seg_entry { - unsigned short valid_blocks; /* # of valid blocks */ + unsigned int type:6; /* segment type like CURSEG_XXX_TYPE */ + unsigned int valid_blocks:10; /* # of valid blocks */ + unsigned int ckpt_valid_blocks:10; /* # of valid blocks last cp */ + unsigned int padding:6; /* padding */ unsigned char *cur_valid_map; /* validity bitmap of blocks */ /* * # of valid blocks and the validity bitmap stored in the the last * checkpoint pack. This information is used by the SSR mode. */ - unsigned short ckpt_valid_blocks; - unsigned char *ckpt_valid_map; + unsigned char *ckpt_valid_map; /* validity bitmap of blocks last cp */ unsigned char *discard_map; - unsigned char type; /* segment type like CURSEG_XXX_TYPE */ unsigned long long mtime; /* modification time of the segment */ }; -- 2.7.2