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/fork.c b/kernel/fork.c
index 8b20ab7..7798c24 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1442,7 +1442,7 @@
if (thread_group_leader(p)) {
if (is_child_reaper(pid))
- p->nsproxy->pid_ns->child_reaper = p;
+ ns_of_pid(pid)->child_reaper = p;
p->signal->leader_pid = pid;
p->signal->tty = tty_kref_get(current->signal->tty);