openvswitch: Use RCU callback when detaching netdevices.
Currently, each time a device is detached from an OVS datapath
we call synchronize RCU before freeing associated data structures.
However, if a bridge is deleted (which detaches all ports) when
many devices are connected then there can be a long delay. This
switches to use call_rcu() to group the cost together.
Reported-by: Justin Pettit <jpettit@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
diff --git a/net/openvswitch/vport-netdev.c b/net/openvswitch/vport-netdev.c
index a903348..a9327e2 100644
--- a/net/openvswitch/vport-netdev.c
+++ b/net/openvswitch/vport-netdev.c
@@ -114,6 +114,15 @@
return ERR_PTR(err);
}
+static void free_port_rcu(struct rcu_head *rcu)
+{
+ struct netdev_vport *netdev_vport = container_of(rcu,
+ struct netdev_vport, rcu);
+
+ dev_put(netdev_vport->dev);
+ ovs_vport_free(vport_from_priv(netdev_vport));
+}
+
static void netdev_destroy(struct vport *vport)
{
struct netdev_vport *netdev_vport = netdev_vport_priv(vport);
@@ -122,10 +131,7 @@
netdev_rx_handler_unregister(netdev_vport->dev);
dev_set_promiscuity(netdev_vport->dev, -1);
- synchronize_rcu();
-
- dev_put(netdev_vport->dev);
- ovs_vport_free(vport);
+ call_rcu(&netdev_vport->rcu, free_port_rcu);
}
const char *ovs_netdev_get_name(const struct vport *vport)
diff --git a/net/openvswitch/vport-netdev.h b/net/openvswitch/vport-netdev.h
index f7072a2..6478079 100644
--- a/net/openvswitch/vport-netdev.h
+++ b/net/openvswitch/vport-netdev.h
@@ -20,12 +20,15 @@
#define VPORT_NETDEV_H 1
#include <linux/netdevice.h>
+#include <linux/rcupdate.h>
#include "vport.h"
struct vport *ovs_netdev_get_vport(struct net_device *dev);
struct netdev_vport {
+ struct rcu_head rcu;
+
struct net_device *dev;
};