From: Oleg Nesterov <oleg@redhat.com>
Date: Wed, 8 Jul 2015 19:42:13 +0000 (+0200)
Subject: net: pktgen: kill the "Wait for kthread_stop" code in pktgen_thread_worker()
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1fbe4b46caca;p=linux-beck.git

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 41489e3c69af..1ebdf1c0d118 100644
--- 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);
 	}