[PATCH net-next v2] openvswitch: Print error when ovs_execute_actions() fails

[Yifeng Sun <pkusunyifeng@gmail.com>]

Currently in function ovs_dp_process_packet(), return values of
ovs_execute_actions() are silently discarded. This patch prints out
an debug message when error happens so as to provide helpful hints
for debugging.
---
v1->v2: Fixed according to Pravin's review.

 net/openvswitch/datapath.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 892287d..12d9850 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -222,6 +222,7 @@ void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key)
 	struct dp_stats_percpu *stats;
 	u64 *stats_counter;
 	u32 n_mask_hit;
+	int error;
 
 	stats = this_cpu_ptr(dp->stats_percpu);
 
@@ -229,7 +230,6 @@ void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key)
 	flow = ovs_flow_tbl_lookup_stats(&dp->table, key, &n_mask_hit);
 	if (unlikely(!flow)) {
 		struct dp_upcall_info upcall;
-		int error;
 
 		memset(&upcall, 0, sizeof(upcall));
 		upcall.cmd = OVS_PACKET_CMD_MISS;
@@ -246,7 +246,10 @@ void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key)
 
 	ovs_flow_stats_update(flow, key->tp.flags, skb);
 	sf_acts = rcu_dereference(flow->sf_acts);
-	ovs_execute_actions(dp, skb, sf_acts, key);
+	error = ovs_execute_actions(dp, skb, sf_acts, key);
+	if (unlikely(error))
+		net_dbg_ratelimited("ovs: action execution error on datapath %s: %d\n",
+							ovs_dp_name(dp), error);
 
 	stats_counter = &stats->n_hit;
 
-- 
2.7.4