[PATCH rdma-next 02/10] IB/ipoib: Use cancel_delayed_work_sync for neigh-clean task

[Leon Romanovsky]

From: Erez Shitrit <ere...@mellanox.com>

The neigh_reap_task is self restarting, but so long as we call
cancel_delayed_work_sync() it will be guaranteed to not be running and
never start again. Thus we don't need to have the racy
IPOIB_STOP_NEIGH_GC bit, or the confusing mismatch of places sometimes
calling flush_workqueue after the cancel.

This fixes a situation where the GC work could have been left running
in some rare situations.

Signed-off-by: Erez Shitrit <ere...@mellanox.com>
Signed-off-by: Leon Romanovsky <leo...@mellanox.com>
---
 drivers/infiniband/ulp/ipoib/ipoib_main.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c 
b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 7ca9013bf05c..7cd42619deb2 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -1661,7 +1661,7 @@ static void ipoib_neigh_hash_uninit(struct net_device 
*dev)
        /* Stop GC if called at init fail need to cancel work */
        stopped = test_and_set_bit(IPOIB_STOP_NEIGH_GC, &priv->flags);
        if (!stopped)
-               cancel_delayed_work(&priv->neigh_reap_task);
+               cancel_delayed_work_sync(&priv->neigh_reap_task);
 
        ipoib_flush_neighs(priv);
 
@@ -1837,7 +1837,7 @@ void ipoib_dev_cleanup(struct net_device *dev)
        list_for_each_entry_safe(cpriv, tcpriv, &priv->child_intfs, list) {
                /* Stop GC on child */
                set_bit(IPOIB_STOP_NEIGH_GC, &cpriv->flags);
-               cancel_delayed_work(&cpriv->neigh_reap_task);
+               cancel_delayed_work_sync(&cpriv->neigh_reap_task);
                unregister_netdevice_queue(cpriv->dev, &head);
        }
        unregister_netdevice_many(&head);
@@ -2346,7 +2346,7 @@ static struct net_device *ipoib_add_port(const char 
*format,
        flush_workqueue(ipoib_workqueue);
        /* Stop GC if started before flush */
        set_bit(IPOIB_STOP_NEIGH_GC, &priv->flags);
-       cancel_delayed_work(&priv->neigh_reap_task);
+       cancel_delayed_work_sync(&priv->neigh_reap_task);
        flush_workqueue(priv->wq);
        ipoib_dev_cleanup(priv->dev);
 
@@ -2412,7 +2412,7 @@ static void ipoib_remove_one(struct ib_device *device, 
void *client_data)
 
                /* Stop GC */
                set_bit(IPOIB_STOP_NEIGH_GC, &priv->flags);
-               cancel_delayed_work(&priv->neigh_reap_task);
+               cancel_delayed_work_sync(&priv->neigh_reap_task);
                flush_workqueue(priv->wq);
 
                /* Wrap rtnl_lock/unlock with mutex to protect sysfs calls */
-- 
2.14.4