udp: fix rx event generation

When session is owned by another thread, avoid postponing the generation
of the rx event.

Type:fix

Change-Id: Ie6afc8116ce40e83d8aae0432b48e19b31287d8b
Signed-off-by: Florin Coras <fcoras@cisco.com>

diff --git a/src/vnet/udp/udp_input.c b/src/vnet/udp/udp_input.c
index ad86f43..e5a8242 100644 (file)
--- a/src/vnet/udp/udp_input.c
+++ b/src/vnet/udp/udp_input.c
@@ -225,8 +225,8 @@ udp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
                      error0 = UDP_ERROR_CREATE_SESSION;
                      goto trace0;
                    }
-                 s0 =
-                   session_get (child0->c_s_index, child0->c_thread_index);
+                 s0 = session_get (child0->c_s_index,
+                                   child0->c_thread_index);
                  s0->session_state = SESSION_STATE_READY;
                  tc0 = &child0->connection;
                  uc0 = udp_get_connection_from_transport (tc0);
@@ -255,9 +255,22 @@ udp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
          hdr0.is_ip4 = is_ip4;
 
          clib_spinlock_lock (&uc0->rx_lock);
-         wrote0 = session_enqueue_dgram_connection (s0, &hdr0, b0,
-                                                    TRANSPORT_PROTO_UDP,
-                                                    queue_event);
+         /* If session is owned by another thread and rx event needed,
+          * enqueue event now while we still have the peeker lock */
+         if (s0->thread_index != my_thread_index)
+           {
+             wrote0 = session_enqueue_dgram_connection (s0, &hdr0, b0,
+                                                        TRANSPORT_PROTO_UDP,
+                                                        /* queue event */ 0);
+             if (queue_event && !svm_fifo_has_event (s0->rx_fifo))
+               session_enqueue_notify (s0);
+           }
+         else
+           {
+             wrote0 = session_enqueue_dgram_connection (s0, &hdr0, b0,
+                                                        TRANSPORT_PROTO_UDP,
+                                                        queue_event);
+           }
          clib_spinlock_unlock (&uc0->rx_lock);
          ASSERT (wrote0 > 0);
 
@@ -287,7 +300,8 @@ udp46_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
     }
 
-  errors = session_main_flush_all_enqueue_events (TRANSPORT_PROTO_UDP);
+  errors = session_main_flush_enqueue_events (TRANSPORT_PROTO_UDP,
+                                             my_thread_index);
   udp_input_inc_counter (vm, is_ip4, UDP_ERROR_EVENT_FIFO_FULL, errors);
   return frame->n_vectors;
 }