cgroup: Call cgroup_release() before __exit_signal()

cgroup_release() calls cgroup_subsys->release() which is used by the
pids controller to uncharge its pid.  We want to use it to manage
iteration of dying tasks which requires putting it before
__unhash_process().  Move cgroup_release() above __exit_signal().
While this makes it uncharge before the pid is freed, pid is RCU freed
anyway and the window is very narrow.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
This commit is contained in:
Tejun Heo 2019-05-31 10:38:57 -07:00
parent 8cfeb385e9
commit 6b115bf58e

View File

@ -195,6 +195,7 @@ repeat:
rcu_read_unlock();
proc_flush_task(p);
cgroup_release(p);
write_lock_irq(&tasklist_lock);
ptrace_release_task(p);
@ -220,7 +221,6 @@ repeat:
}
write_unlock_irq(&tasklist_lock);
cgroup_release(p);
release_thread(p);
call_rcu(&p->rcu, delayed_put_task_struct);