5 files changed, 30 insertions, 24 deletions

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index 98d393e70de3..a3f1204f1ed2 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -778,7 +778,7 @@ static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
 			}
 		}
 		/* Non-ICMP, fall thru to initialize if needed. */
-		/* fall through */
+		fallthrough;
 	case IP_CT_NEW:
 		/* Seen it before?  This can happen for loopback, retrans,
 		 * or local packets.
@@ -1540,7 +1540,7 @@ static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
 		switch (type) {
 		case OVS_CT_ATTR_FORCE_COMMIT:
 			info->force = true;
-			/* fall through. */
+			fallthrough;
 		case OVS_CT_ATTR_COMMIT:
 			info->commit = true;
 			break;
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 42f8cc70bb2c..6e47ef7ef036 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -1756,6 +1756,7 @@ err:
 /* Called with ovs_mutex. */
 static void __dp_destroy(struct datapath *dp)
 {
+	struct flow_table *table = &dp->table;
 	int i;
 
 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
@@ -1774,7 +1775,14 @@ static void __dp_destroy(struct datapath *dp)
 	 */
 	ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
 
-	/* RCU destroy the flow table */
+	/* Flush sw_flow in the tables. RCU cb only releases resource
+	 * such as dp, ports and tables. That may avoid some issues
+	 * such as RCU usage warning.
+	 */
+	table_instance_flow_flush(table, ovsl_dereference(table->ti),
+				  ovsl_dereference(table->ufid_ti));
+
+	/* RCU destroy the ports, meters and flow tables. */
 	call_rcu(&dp->rcu, destroy_dp_rcu);
 }
 
diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c
index 03942c30d83e..b03d142ec82e 100644
--- a/net/openvswitch/flow.c
+++ b/net/openvswitch/flow.c
@@ -675,7 +675,7 @@ static int key_extract_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
 			case -EINVAL:
 				memset(&key->ip, 0, sizeof(key->ip));
 				memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
-				/* fall-through */
+				fallthrough;
 			case -EPROTO:
 				skb->transport_header = skb->network_header;
 				error = 0;
diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c
index 8c12675cbb67..e2235849a57e 100644
--- a/net/openvswitch/flow_table.c
+++ b/net/openvswitch/flow_table.c
@@ -473,19 +473,15 @@ static void table_instance_flow_free(struct flow_table *table,
 	flow_mask_remove(table, flow->mask);
 }
 
-static void table_instance_destroy(struct flow_table *table,
-				   struct table_instance *ti,
-				   struct table_instance *ufid_ti,
-				   bool deferred)
+/* Must be called with OVS mutex held. */
+void table_instance_flow_flush(struct flow_table *table,
+			       struct table_instance *ti,
+			       struct table_instance *ufid_ti)
 {
 	int i;
 
-	if (!ti)
-		return;
-
-	BUG_ON(!ufid_ti);
 	if (ti->keep_flows)
-		goto skip_flows;
+		return;
 
 	for (i = 0; i < ti->n_buckets; i++) {
 		struct sw_flow *flow;
@@ -497,18 +493,16 @@ static void table_instance_destroy(struct flow_table *table,
 
 			table_instance_flow_free(table, ti, ufid_ti,
 						 flow, false);
-			ovs_flow_free(flow, deferred);
+			ovs_flow_free(flow, true);
 		}
 	}
+}
 
-skip_flows:
-	if (deferred) {
-		call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
-		call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb);
-	} else {
-		__table_instance_destroy(ti);
-		__table_instance_destroy(ufid_ti);
-	}
+static void table_instance_destroy(struct table_instance *ti,
+				   struct table_instance *ufid_ti)
+{
+	call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);
+	call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb);
 }
 
 /* No need for locking this function is called from RCU callback or
@@ -523,7 +517,7 @@ void ovs_flow_tbl_destroy(struct flow_table *table)
 
 	call_rcu(&mc->rcu, mask_cache_rcu_cb);
 	call_rcu(&ma->rcu, mask_array_rcu_cb);
-	table_instance_destroy(table, ti, ufid_ti, false);
+	table_instance_destroy(ti, ufid_ti);
 }
 
 struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti,
@@ -641,7 +635,8 @@ int ovs_flow_tbl_flush(struct flow_table *flow_table)
 	flow_table->count = 0;
 	flow_table->ufid_count = 0;
 
-	table_instance_destroy(flow_table, old_ti, old_ufid_ti, true);
+	table_instance_flow_flush(flow_table, old_ti, old_ufid_ti);
+	table_instance_destroy(old_ti, old_ufid_ti);
 	return 0;
 
 err_free_ti:
diff --git a/net/openvswitch/flow_table.h b/net/openvswitch/flow_table.h
index 74ce48fecba9..6e7d4ac59353 100644
--- a/net/openvswitch/flow_table.h
+++ b/net/openvswitch/flow_table.h
@@ -105,5 +105,8 @@ void ovs_flow_mask_key(struct sw_flow_key *dst, const struct sw_flow_key *src,
 		       bool full, const struct sw_flow_mask *mask);
 
 void ovs_flow_masks_rebalance(struct flow_table *table);
+void table_instance_flow_flush(struct flow_table *table,
+			       struct table_instance *ti,
+			       struct table_instance *ufid_ti);
 
 #endif /* flow_table.h */