maximum packet size support 9k - simulation

2 files changed, 43 insertions, 3 deletions

diff --git a/src/stateless/dp/trex_stateless_dp_core.cpp b/src/stateless/dp/trex_stateless_dp_core.cpp
index c211b9f5..6e936fc8 100644
--- a/src/stateless/dp/trex_stateless_dp_core.cpp
+++ b/src/stateless/dp/trex_stateless_dp_core.cpp
@@ -149,10 +149,34 @@ rte_mbuf_t   * CGenNodeStateless::alloc_node_with_vm(){
                 m_vm_flow_var,
                 (uint8_t*)p);
 
+    uint16_t pkt_new_size=runner.get_new_pkt_size();
+    if ( likely( pkt_new_size == 0) ) {
+        /* no packet size change */
+        rte_mbuf_t * m_const = get_const_mbuf();
+        if (  m_const != NULL) {
+            utl_rte_pktmbuf_add_after(m,m_const);
+        }
+        return (m);
+    }
 
+    /* packet size change there are a few changes */
     rte_mbuf_t * m_const = get_const_mbuf();
-    if (  m_const != NULL) {
-        utl_rte_pktmbuf_add_after(m,m_const);
+    if ( (m_const == 0 ) || (pkt_new_size<=prefix_size) ) {
+        /* one mbuf , just trim it */
+        m->data_len = pkt_new_size;
+        m->pkt_len  = pkt_new_size;
+        return (m);
+    }
+
+    rte_mbuf_t * mi= CGlobalInfo::pktmbuf_alloc_small(get_socket_id());
+    assert(mi);
+    rte_pktmbuf_attach(mi,m_const);
+    utl_rte_pktmbuf_add_after(m,mi);
+
+    if ( pkt_new_size < m->pkt_len) {
+        /* need to trim it */
+        mi->data_len = (pkt_new_size - prefix_size);
+        m->pkt_len   = pkt_new_size;
     }
     return (m);
 }
@@ -614,6 +638,12 @@ TrexStatelessDpCore::add_stream(TrexStatelessDpPerPort * lp_port,
         }
 
 
+        if ( lpDpVm->is_pkt_size_var() ) {
+            // mark the node as varible size 
+            node->set_var_pkt_size();
+        }
+
+
         if (lpDpVm->get_prefix_size() > pkt_size ) {
             lpDpVm->set_prefix_size(pkt_size);
         }
diff --git a/src/stateless/dp/trex_stream_node.h b/src/stateless/dp/trex_stream_node.h
index 70a66e6a..dfa4cc13 100644
--- a/src/stateless/dp/trex_stream_node.h
+++ b/src/stateless/dp/trex_stream_node.h
@@ -60,7 +60,9 @@ public:
         SL_NODE_FLAGS_DIR                  =1, //USED by master
         SL_NODE_FLAGS_MBUF_CACHE           =2, //USED by master
 
-        SL_NODE_CONST_MBUF                =4
+        SL_NODE_CONST_MBUF                 =4,
+
+        SL_NODE_VAR_PKT_SIZE               =8
 
     };
 
@@ -282,6 +284,14 @@ public:
         }
     }
 
+    inline void set_var_pkt_size(){
+        m_flags |= SL_NODE_VAR_PKT_SIZE;
+    }
+
+    inline bool is_var_pkt_size(){
+        return ( ( m_flags &SL_NODE_VAR_PKT_SIZE )?true:false);
+    }
+
     inline void set_const_mbuf(rte_mbuf_t * m){
         m_cache_mbuf=(void *)m;
         m_flags |= SL_NODE_CONST_MBUF;