pidns: Use task_active_pid_ns where appropriate
The expressions tsk->nsproxy->pid_ns and task_active_pid_ns
aka ns_of_pid(task_pid(tsk)) should have the same number of
cache line misses with the practical difference that
ns_of_pid(task_pid(tsk)) is released later in a processes life.
Furthermore by using task_active_pid_ns it becomes trivial
to write an unshare implementation for the the pid namespace.
So I have used task_active_pid_ns everywhere I can.
In fork since the pid has not yet been attached to the
process I use ns_of_pid, to achieve the same effect.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/kernel/signal.c b/kernel/signal.c
index 0af8868..b2445d8 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1752,7 +1752,7 @@
* see comment in do_notify_parent() about the following 4 lines
*/
rcu_read_lock();
- info.si_pid = task_pid_nr_ns(tsk, parent->nsproxy->pid_ns);
+ info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(parent));
info.si_uid = from_kuid_munged(task_cred_xxx(parent, user_ns), task_uid(tsk));
rcu_read_unlock();