From: Jeff Layton <jlayton@redhat.com>
Date: Mon, 25 Mar 2013 11:59:57 +0000 (-0400)
Subject: nfs: allow the v4.1 callback thread to freeze
X-Git-Tag: next-20130422~99^2~25
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=25d280aad82e559cc7bc762410cd35ea5b98e294;p=karo-tx-linux.git

nfs: allow the v4.1 callback thread to freeze

The v4.1 callback thread has set_freezable() at the top, but it doesn't
ever try to freeze within the loop. Have it call try_to_freeze() at the
top of the loop. If a freeze event occurs, recheck kthread_should_stop()
after thawing.

Reported-by: Yanchuan Nian <ycnian@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 5088b57b078a..cff089a412c7 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -125,6 +125,9 @@ nfs41_callback_svc(void *vrqstp)
 	set_freezable();
 
 	while (!kthread_should_stop()) {
+		if (try_to_freeze())
+			continue;
+
 		prepare_to_wait(&serv->sv_cb_waitq, &wq, TASK_INTERRUPTIBLE);
 		spin_lock_bh(&serv->sv_cb_lock);
 		if (!list_empty(&serv->sv_cb_list)) {