session: reschedule asap when snd space constrained

Type: feature

Improves fairness for sessions that are snd space or pacer constrained.

Change-Id: Ida5f523090f1dcbfb17bf5116bc7917747ac8593
Signed-off-by: Florin Coras <fcoras@cisco.com>
diff --git a/src/vnet/session/session.h b/src/vnet/session/session.h
index f738f39..9fe35b1 100644
--- a/src/vnet/session/session.h
+++ b/src/vnet/session/session.h
@@ -221,6 +221,14 @@
 		       pool_elt_at_index (wrk->event_elts, wrk->old_head));
 }
 
+static inline void
+session_evt_add_head_old (session_worker_t * wrk, session_evt_elt_t * elt)
+{
+  clib_llist_add (wrk->event_elts, evt_list, elt,
+		  pool_elt_at_index (wrk->event_elts, wrk->old_head));
+}
+
+
 static inline u32
 session_evt_ctrl_data_alloc (session_worker_t * wrk)
 {