[PATCH] reduce sizeof(struct file)
Now that RCU applied on 'struct file' seems stable, we can place f_rcuhead
in a memory location that is not anymore used at call_rcu(&f->f_rcuhead,
file_free_rcu) time, to reduce the size of this critical kernel object.
The trick I used is to move f_rcuhead and f_list in an union called f_u
The callers are changed so that f_rcuhead becomes f_u.fu_rcuhead and f_list
becomes f_u.f_list
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index d50d7a7..bb62838 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1609,7 +1609,7 @@
if (tty) {
file_list_lock();
- file = list_entry(tty->tty_files.next, typeof(*file), f_list);
+ file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
if (file) {
/* Revalidate access to controlling tty.
Use inode_has_perm on the tty inode directly rather