From af4b8a83add95ef40716401395b44a1b579965f4 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 1 Aug 2012 15:03:42 -0700 Subject: pidns: Wait in zap_pid_ns_processes until pid_ns->nr_hashed == 1 Looking at pid_ns->nr_hashed is a bit simpler and it works for disjoint process trees that an unshare or a join of a pid_namespace may create. Acked-by: "Serge E. Hallyn" Signed-off-by: "Eric W. Biederman" --- kernel/pid.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) (limited to 'kernel/pid.c') diff --git a/kernel/pid.c b/kernel/pid.c index 9c219117af36..6e8da291de49 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -273,10 +273,20 @@ void free_pid(struct pid *pid) spin_lock_irqsave(&pidmap_lock, flags); for (i = 0; i <= pid->level; i++) { struct upid *upid = pid->numbers + i; + struct pid_namespace *ns = upid->ns; hlist_del_rcu(&upid->pid_chain); - if (--upid->ns->nr_hashed == 0) { - upid->ns->nr_hashed = -1; - schedule_work(&upid->ns->proc_work); + switch(--ns->nr_hashed) { + case 1: + /* When all that is left in the pid namespace + * is the reaper wake up the reaper. The reaper + * may be sleeping in zap_pid_ns_processes(). + */ + wake_up_process(ns->child_reaper); + break; + case 0: + ns->nr_hashed = -1; + schedule_work(&ns->proc_work); + break; } } spin_unlock_irqrestore(&pidmap_lock, flags); -- cgit v1.2.1