tunnel: Avoid flow_to_string() call when rate-limited.

flow_to_string() is relatively expensive.  It is better to avoid it if the
string is not actually going to be used.

Signed-off-by: Ben Pfaff <blp@ovn.org>
Reviewed-by: Yifeng Sun <pkusunyifeng@gmail.com>
Acked-by: Ansis Atteka <aatteka@ovn.org>

1 files changed, 5 insertions, 4 deletions

diff --git a/ofproto/tunnel.c b/ofproto/tunnel.c
index 1676f4d46..9896d715a 100644
--- a/ofproto/tunnel.c
+++ b/ofproto/tunnel.c
@@ -309,10 +309,11 @@ tnl_port_receive(const struct flow *flow) OVS_EXCLUDED(rwlock)
     tnl_port = tnl_find(flow);
     ofport = tnl_port ? tnl_port->ofport : NULL;
     if (!tnl_port) {
-        char *flow_str = flow_to_string(flow, NULL);
-
-        VLOG_WARN_RL(&rl, "receive tunnel port not found (%s)", flow_str);
-        free(flow_str);
+        if (!VLOG_DROP_WARN(&rl)) {
+            char *flow_str = flow_to_string(flow, NULL);
+            VLOG_WARN("receive tunnel port not found (%s)", flow_str);
+            free(flow_str);
+        }
         goto out;
     }