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| author | Theodore Ts'o <tytso@mit.edu> | 2006-09-27 01:50:46 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-27 08:26:17 -0700 |
| commit | 8e18e2941c53416aa219708e7dcad21fb4bd6794 (patch) | |
| tree | 44118f8b09556193ac93e0b71aecfa3e1d4bc182 /arch/s390 | |
| parent | 6a1d9805ec506d8b9d04450997707da5f643d87c (diff) | |
| download | op-kernel-dev-8e18e2941c53416aa219708e7dcad21fb4bd6794.zip op-kernel-dev-8e18e2941c53416aa219708e7dcad21fb4bd6794.tar.gz | |
[PATCH] inode_diet: Replace inode.u.generic_ip with inode.i_private
The following patches reduce the size of the VFS inode structure by 28 bytes
on a UP x86. (It would be more on an x86_64 system). This is a 10% reduction
in the inode size on a UP kernel that is configured in a production mode
(i.e., with no spinlock or other debugging functions enabled; if you want to
save memory taken up by in-core inodes, the first thing you should do is
disable the debugging options; they are responsible for a huge amount of bloat
in the VFS inode structure).
This patch:
The filesystem or device-specific pointer in the inode is inside a union,
which is pretty pointless given that all 30+ users of this field have been
using the void pointer. Get rid of the union and rename it to i_private, with
a comment to explain who is allowed to use the void pointer. This is just a
cleanup, but it allows us to reuse the union 'u' for something something where
the union will actually be used.
[judith@osdl.org: powerpc build fix]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Judith Lebzelter <judith@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/hypfs/inode.c | 6 | ||||
| -rw-r--r-- | arch/s390/kernel/debug.c | 2 |
2 files changed, 4 insertions, 4 deletions
diff --git a/arch/s390/hypfs/inode.c b/arch/s390/hypfs/inode.c index bdade5f..8735024 100644 --- a/arch/s390/hypfs/inode.c +++ b/arch/s390/hypfs/inode.c @@ -104,13 +104,13 @@ static struct inode *hypfs_make_inode(struct super_block *sb, int mode) static void hypfs_drop_inode(struct inode *inode) { - kfree(inode->u.generic_ip); + kfree(inode->i_private); generic_delete_inode(inode); } static int hypfs_open(struct inode *inode, struct file *filp) { - char *data = filp->f_dentry->d_inode->u.generic_ip; + char *data = filp->f_dentry->d_inode->i_private; struct hypfs_sb_info *fs_info; if (filp->f_mode & FMODE_WRITE) { @@ -352,7 +352,7 @@ static struct dentry *hypfs_create_file(struct super_block *sb, parent->d_inode->i_nlink++; } else BUG(); - inode->u.generic_ip = data; + inode->i_private = data; d_instantiate(dentry, inode); dget(dentry); return dentry; diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c index 7ba2092..43f3d0c 100644 --- a/arch/s390/kernel/debug.c +++ b/arch/s390/kernel/debug.c @@ -603,7 +603,7 @@ debug_open(struct inode *inode, struct file *file) debug_info_t *debug_info, *debug_info_snapshot; down(&debug_lock); - debug_info = (struct debug_info*)file->f_dentry->d_inode->u.generic_ip; + debug_info = file->f_dentry->d_inode->i_private; /* find debug view */ for (i = 0; i < DEBUG_MAX_VIEWS; i++) { if (!debug_info->views[i]) |
