[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>
diff --git a/drivers/infiniband/hw/ipath/ipath_fs.c b/drivers/infiniband/hw/ipath/ipath_fs.c
index a5eb30a..055cdd0 100644
--- a/drivers/infiniband/hw/ipath/ipath_fs.c
+++ b/drivers/infiniband/hw/ipath/ipath_fs.c
@@ -64,7 +64,7 @@
inode->i_blksize = PAGE_CACHE_SIZE;
inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
- inode->u.generic_ip = data;
+ inode->i_private = data;
if ((mode & S_IFMT) == S_IFDIR) {
inode->i_op = &simple_dir_inode_operations;
inode->i_nlink++;
@@ -119,7 +119,7 @@
u16 i;
struct ipath_devdata *dd;
- dd = file->f_dentry->d_inode->u.generic_ip;
+ dd = file->f_dentry->d_inode->i_private;
for (i = 0; i < NUM_COUNTERS; i++)
counters[i] = ipath_snap_cntr(dd, i);
@@ -139,7 +139,7 @@
struct ipath_devdata *dd;
u64 guid;
- dd = file->f_dentry->d_inode->u.generic_ip;
+ dd = file->f_dentry->d_inode->i_private;
guid = be64_to_cpu(dd->ipath_guid);
@@ -178,7 +178,7 @@
u32 tmp, tmp2;
struct ipath_devdata *dd;
- dd = file->f_dentry->d_inode->u.generic_ip;
+ dd = file->f_dentry->d_inode->i_private;
/* so we only initialize non-zero fields. */
memset(portinfo, 0, sizeof portinfo);
@@ -325,7 +325,7 @@
goto bail;
}
- dd = file->f_dentry->d_inode->u.generic_ip;
+ dd = file->f_dentry->d_inode->i_private;
if (ipath_eeprom_read(dd, pos, tmp, count)) {
ipath_dev_err(dd, "failed to read from flash\n");
ret = -ENXIO;
@@ -381,7 +381,7 @@
goto bail_tmp;
}
- dd = file->f_dentry->d_inode->u.generic_ip;
+ dd = file->f_dentry->d_inode->i_private;
if (ipath_eeprom_write(dd, pos, tmp, count)) {
ret = -ENXIO;
ipath_dev_err(dd, "failed to write to flash\n");
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_fs.c b/drivers/infiniband/ulp/ipoib/ipoib_fs.c
index 5dde380..f1cb836 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_fs.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_fs.c
@@ -141,7 +141,7 @@
return ret;
seq = file->private_data;
- seq->private = inode->u.generic_ip;
+ seq->private = inode->i_private;
return 0;
}
@@ -247,7 +247,7 @@
return ret;
seq = file->private_data;
- seq->private = inode->u.generic_ip;
+ seq->private = inode->i_private;
return 0;
}