Deprecate find_task_by_pid()

There are some places that are known to operate on tasks'
global pids only:

* the rest_init() call (called on boot)
* the kgdb's getthread
* the create_kthread() (since the kthread is run in init ns)

So use the find_task_by_pid_ns(..., &init_pid_ns) there
and schedule the find_task_by_pid for removal.

[sukadev@us.ibm.com: Fix warning in kernel/pid.c]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 1 insertions, 7 deletions

diff --git a/kernel/kthread.c b/kernel/kthread.c
index ac72eea48339..bd1b9ea024e1 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -98,7 +98,7 @@ static void create_kthread(struct kthread_create_info *create)
                 struct sched_param param = { .sched_priority = 0 };
                 wait_for_completion(&create->started);
                 read_lock(&tasklist_lock);
-                create->result = find_task_by_pid(pid);
+                create->result = find_task_by_pid_ns(pid, &init_pid_ns);
                 read_unlock(&tasklist_lock);
                 /*
                  * root may have changed our (kthreadd's) priority or CPU mask.
diff --git a/kernel/pid.c b/kernel/pid.c
index b322cdf401bf..a9ae9f7fb229 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -381,12 +381,6 @@ struct task_struct *find_task_by_pid_type_ns(int type, int nr,
 
 EXPORT_SYMBOL(find_task_by_pid_type_ns);
 
-struct task_struct *find_task_by_pid(pid_t nr)
-{
-        return find_task_by_pid_type_ns(PIDTYPE_PID, nr, &init_pid_ns);
-}
-EXPORT_SYMBOL(find_task_by_pid);
-
 struct task_struct *find_task_by_vpid(pid_t vnr)
 {
         return find_task_by_pid_type_ns(PIDTYPE_PID, vnr,