[v2] lockd: added cleanup checks in exit_net hook

Commit Message

Vasily Averin Nov. 3, 2017, 6:55 p.m. UTC

Patch generates warnings if exit_net hook detects that 
structures initialized in init_net hook are still in use. 

[ 9313.047796] NFSD: starting 90-second grace period (net ffff880e307fe240)
[ 9317.257203] nfsd: last server has exited, flushing export cache
[ 9320.059256] net ffff880e307fe240 exit: lockd_manager.list is not empty
[ 9320.060434] WARNING: CPU: 5 PID: 1556 at fs/lockd/svc.c:682 lockd_exit_net+0x5c/0x90 [lockd]
...
[ 9320.077346] net ffff880e307fe240 exit: grace_period_end was not canceled
[ 9320.078494] WARNING: CPU: 5 PID: 1556 at fs/lockd/svc.c:686 lockd_exit_net+0x88/0x90 [lockd]

v2: net pointer was added to output
Signed-off-by: Vasily Averin <[e-mail]>
---
 fs/lockd/svc.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Patch

diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index 809cbcc..2f28850 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -690,6 +690,14 @@  static int lockd_init_net(struct net *net)
 
 static void lockd_exit_net(struct net *net)
 {
+	struct lockd_net *ln = net_generic(net, lockd_net_id);
+
+	WARN(!list_empty(&ln->lockd_manager.list),
+	     "net %p exit: lockd_manager.list is not empty\n", net);
+	WARN(!list_empty(&ln->nsm_handles),
+	     "net %p exit: nsm_handles list is not empty\n", net);
+	WARN(delayed_work_pending(&ln->grace_period_end),
+	     "net %p exit: grace_period_end was not canceled\n", net);
 }
 
 static struct pernet_operations lockd_net_ops = {