openvswitch: Move table destroy to dp-rcu callback.

Ths simplifies flow-table-destroy API. No need to pass explicit
parameter about context.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Thomas Graf <tgraf@redhat.com>

net/openvswitch/datapath.c

@@ -187,6 +187,7 @@ static void destroy_dp_rcu(struct rcu_head *rcu)
 {
 	struct datapath *dp = container_of(rcu, struct datapath, rcu);
 
+	ovs_flow_tbl_destroy(&dp->table);
 	free_percpu(dp->stats_percpu);
 	release_net(ovs_dp_get_net(dp));
 	kfree(dp->ports);
@@ -1444,7 +1445,7 @@ err_destroy_ports_array:
 err_destroy_percpu:
 	free_percpu(dp->stats_percpu);
 err_destroy_table:
-	ovs_flow_tbl_destroy(&dp->table, false);
+	ovs_flow_tbl_destroy(&dp->table);
 err_free_dp:
 	release_net(ovs_dp_get_net(dp));
 	kfree(dp);
@@ -1476,8 +1477,6 @@ static void __dp_destroy(struct datapath *dp)
 	ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
 
 	/* RCU destroy the flow table */
-	ovs_flow_tbl_destroy(&dp->table, true);
-
 	call_rcu(&dp->rcu, destroy_dp_rcu);
 }
 

net/openvswitch/flow_table.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007-2013 Nicira, Inc.
+ * Copyright (c) 2007-2014 Nicira, Inc.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of version 2 of the GNU General Public
@@ -250,11 +250,14 @@ skip_flows:
 		__table_instance_destroy(ti);
 }
 
-void ovs_flow_tbl_destroy(struct flow_table *table, bool deferred)
+/* No need for locking this function is called from RCU callback or
+ * error path.
+ */
+void ovs_flow_tbl_destroy(struct flow_table *table)
 {
-	struct table_instance *ti = ovsl_dereference(table->ti);
+	struct table_instance *ti = rcu_dereference_raw(table->ti);
 
-	table_instance_destroy(ti, deferred);
+	table_instance_destroy(ti, false);
 }
 
 struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti,

net/openvswitch/flow_table.h

@@ -62,7 +62,7 @@ void ovs_flow_free(struct sw_flow *, bool deferred);
 
 int ovs_flow_tbl_init(struct flow_table *);
 int ovs_flow_tbl_count(struct flow_table *table);
-void ovs_flow_tbl_destroy(struct flow_table *table, bool deferred);
+void ovs_flow_tbl_destroy(struct flow_table *table);
 int ovs_flow_tbl_flush(struct flow_table *flow_table);
 
 int ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow,