From mboxrd@z Thu Jan 1 00:00:00 1970 From: Miao Xie Subject: [PATCH 02/18] btrfs: Calculate member variant's address directly for btrfs_##name Date: Thu, 25 Mar 2010 20:28:18 +0800 Message-ID: <4BAB56E2.6050809@cn.fujitsu.com> Reply-To: miaox@cn.fujitsu.com Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: Linux Btrfs To: Chris Mason Return-path: List-ID: From: Zhao Lei It can decrease a additional address calculation and increase little speed. Signed-off-by: Zhao Lei Signed-off-by: Miao Xie --- fs/btrfs/struct-funcs.c | 10 +++++----- 1 files changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/struct-funcs.c b/fs/btrfs/struct-funcs.c index c0f7eca..b0f80c0 100644 --- a/fs/btrfs/struct-funcs.c +++ b/fs/btrfs/struct-funcs.c @@ -49,13 +49,13 @@ u##bits btrfs_##name(struct extent_buffer *eb, \ { \ unsigned long part_offset = (unsigned long)s; \ unsigned long offset = part_offset + offsetof(type, member); \ - type *p; \ + u##bits *p; \ /* ugly, but we want the fast path here */ \ if (eb->map_token && offset >= eb->map_start && \ offset + sizeof(((type *)0)->member) <= eb->map_start + \ eb->map_len) { \ - p = (type *)(eb->kaddr + part_offset - eb->map_start); \ - return le##bits##_to_cpu(p->member); \ + p = (u##bits *)(eb->kaddr + offset - eb->map_start); \ + return le##bits##_to_cpu(*p); \ } \ { \ int err; \ @@ -74,8 +74,8 @@ u##bits btrfs_##name(struct extent_buffer *eb, \ read_eb_member(eb, s, type, member, &leres); \ return le##bits##_to_cpu(leres); \ } \ - p = (type *)(kaddr + part_offset - map_start); \ - res = le##bits##_to_cpu(p->member); \ + p = (u##bits *)(kaddr + offset - map_start); \ + res = le##bits##_to_cpu(*p); \ if (unmap_on_exit) \ unmap_extent_buffer(eb, map_token, KM_USER1); \ return res; \ -- 1.6.5.2