2008-08-26 15:23:43

by Richard Kennedy

[permalink] [raw]
Subject: [PATCH] NFS: remove 8 bytes of padding from struct nfs_fattr on 64 bit builds

remove 8 bytes of padding from struct nfs_fattr on 64 bit builds

This also removes padding from several nfs structures, including
16 bytes from nfs4_opendata, nfs4_createdata,nfs3_createdata
& 8 bytes from nfs_read_data,nfs_write_data,nfs_removeres,nfs4_closedata

This also reduces the reported stack usage of many nfs functions (30+).

Signed-off-by: Richard Kennedy <[email protected]>
----

This patch is against the latest git 2.6.27-rc4.
I've built & run this on my AMD64 desktop, & successfully run _simple_
tests with a 64 bit client => 32 bit server & 32 bit client to 64 bit
server.

On fedora with gcc (GCC) 4.3.0 20080428 (Red Hat 4.3.0-8) checkpatch
reports 33 functions with reduced stack usage.
e.g.
__nfs_revalidate_inode [nfs] 216 => 200
_nfs4_proc_access [nfs] 304 => 288
_nfs4_proc_link [nfs] 536 => 504
_nfs4_proc_remove [nfs] 304 => 288
_nfs4_proc_rename [nfs] 584 => 552
nfs3_proc_access [nfs] 272 => 256
nfs3_proc_getacl [nfs] 384 => 368
nfs3_proc_link [nfs] 496 => 464
etc
I can supply the complete list if anyone is interested.

regards
Richard



diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 8c77c11..9cabbb3 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -36,6 +36,7 @@ struct nfs_fattr {
__u32 nlink;
__u32 uid;
__u32 gid;
+ dev_t rdev;
__u64 size;
union {
struct {
@@ -46,7 +47,6 @@ struct nfs_fattr {
__u64 used;
} nfs3;
} du;
- dev_t rdev;
struct nfs_fsid fsid;
__u64 fileid;
struct timespec atime;