net: pktgen: kill the "Wait for kthread_stop" code in pktgen_thread_worker()

pktgen_thread_worker() doesn't need to wait for kthread_stop(), it
can simply exit. Just pktgen_create_thread() and pg_net_exit() should
do get_task_struct()/put_task_struct(). kthread_stop(dead_thread) is
fine.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 41489e3..1ebdf1c 100644 (file)
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -3571,15 +3571,6 @@ static int pktgen_thread_worker(void *arg)
        pr_debug("%s removing thread\n", t->tsk->comm);
        pktgen_rem_thread(t);
 
-       /* Wait for kthread_stop */
-       for (;;) {
-               set_current_state(TASK_INTERRUPTIBLE);
-               if (kthread_should_stop())
-                       break;
-               schedule();
-       }
-       __set_current_state(TASK_RUNNING);
-
        return 0;
 }
 
@@ -3771,6 +3762,7 @@ static int __net_init pktgen_create_thread(int cpu, struct pktgen_net *pn)
        }
 
        t->net = pn;
+       get_task_struct(p);
        wake_up_process(p);
        wait_for_completion(&t->start_done);
 
@@ -3893,6 +3885,7 @@ static void __net_exit pg_net_exit(struct net *net)
                t = list_entry(q, struct pktgen_thread, th_list);
                list_del(&t->th_list);
                kthread_stop(t->tsk);
+               put_task_struct(t->tsk);
                kfree(t);
        }