Fix bug that ARP replies are generated in ANALYZE mode

CHANGELOG.md

@@ -5,6 +5,7 @@
   - Increase meter entries & register entries to 512 to be able to use ports with PID > 255
 - Bug in analyze mode that returned an error when no streams / stream settings were provided
 - Preliminary import/export function for settings
+- Fix bug that prevents that ARP replies are always generated in ANALYZE mode
 
 ## v2.2.0
 - Added VxLAN support

Controller/src/core/traffic_gen.rs

@@ -438,6 +438,9 @@ impl TrafficGen {
         state.frame_type_monitor.lock().await.on_start(switch, &mode).await?;
         state.rate_monitor.lock().await.on_start(switch, &mode).await?;
 
+        // configure tg mode
+        self.configure_traffic_gen_mode_table(switch, &mode).await?;
+
         // configure default forwarding
         // this pushes rules for RX -> RX Recirc and TX Recirc -> TX
         self.configure_default_forwarding_path(switch, &state.port_mapping).await?;
@@ -782,9 +785,22 @@ impl TrafficGen {
         Ok(app_to_offset)
     }
 
+    /// Configures the traffic gen mode table in the data plane
+    /// that is used to detect the generation mode
+    async fn configure_traffic_gen_mode_table(&self, switch: &SwitchConnection, mode: &GenerationMode) -> Result<(), RBFRTError> {
+        let req = Request::new(TRAFFIC_GEN_MODE)
+            .match_key("ig_intr_md.ingress_port", MatchValue::lpm(0, 0))
+            .action("ingress.set_mode")
+            .action_data("mode", *mode as u8);
+
+        switch.write_table_entry(req).await?;
+
+        Ok(())
+    }
+
     /// Clears various tables that are refilled during traffic gen setup
     async fn reset_tables(&self, switch: &SwitchConnection) -> Result<(), RBFRTError> {
-        switch.clear_tables(vec![IS_EGRESS_TABLE, IS_TX_EGRESS_TABLE, VLAN_HEADER_REPLACE_TABLE, MPLS_HEADER_REPLACE_TABLE,  ETHERNET_IP_HEADER_REPLACE_TABLE, DEFAULT_FORWARD_TABLE]).await?;
+        switch.clear_tables(vec![TRAFFIC_GEN_MODE, IS_EGRESS_TABLE, IS_TX_EGRESS_TABLE, VLAN_HEADER_REPLACE_TABLE, MPLS_HEADER_REPLACE_TABLE,  ETHERNET_IP_HEADER_REPLACE_TABLE, DEFAULT_FORWARD_TABLE]).await?;
 
         Ok(())
     }

Controller/src/core/traffic_gen_core/const_definitions.rs

@@ -55,6 +55,9 @@ pub const MONITORING_FORWARD_TABLE: &str = "ingress.p4tg.monitor_forward";
 /// Triggers monitoring in egress for individual streams
 pub const MONITORING_EGRESS_TABLE: &str = "egress.monitor_stream";
 
+/// Indicates the current generation type
+pub const TRAFFIC_GEN_MODE: &str = "ingress.tg_mode";
+
 /// Table that indicates that a packet is on a front panel egress port.
 /// If thats the case, the packet is timestamped for RTT calculation.
 pub const IS_EGRESS_TABLE: &str = "egress.is_egress";

P4-Implementation/src/headers.p4

@@ -37,6 +37,8 @@ const bit<8> IP_PROTOCOL_P4TG = 110;
 const bit<16> UDP_VxLAN_PORT = 4789;
 const bit<16> UDP_P4TG_PORT = 50083;
 
+const bit<8> TG_MODE_ANALYZE = 4;
+
 
 
 header ethernet_h {
@@ -192,6 +194,7 @@ struct ingress_metadata_t {
     PortId_t ig_port;
     bit<1> vxlan;
     bit<1> arp_reply;
+    bit<8> tg_mode;
 }
 
 struct egress_metadata_t {

P4-Implementation/src/ingress.p4

@@ -9,7 +9,23 @@ control ingress(
     P4TG_Ingress() p4tg;
     ARP() arp;
 
+    action set_mode(bit<8> mode) {
+        ig_md.tg_mode = mode;
+    }
+
+    table tg_mode {
+        key = {
+            ig_intr_md.ingress_port: lpm;
+        }
+        actions = {
+            set_mode;
+        }
+        size = 1;
+    }
+
     apply {
+        tg_mode.apply();
+
         arp.apply(hdr, ig_md, ig_intr_md, ig_tm_md);
         p4tg.apply(hdr, ig_md, ig_intr_md, ig_prsr_md, ig_dprsr_md, ig_tm_md);
     }

P4-Implementation/src/libs/ingress/ARP.p4

@@ -45,7 +45,7 @@ control ARP(inout header_t hdr, inout ingress_metadata_t ig_md, in ingress_intri
     }
 
     apply {
-        if(hdr.arp.isValid() && hdr.arp.op == 1) { // it's an arp request
+        if(hdr.arp.isValid() && hdr.arp.op == 1 && ig_md.tg_mode != TG_MODE_ANALYZE) { // it's an arp request
             if(arp_reply.apply().hit) {
                 if(ig_md.arp_reply == 0) {
                     invalidate(ig_tm_md.ucast_egress_port);

P4-Implementation/src/parser.p4

@@ -53,6 +53,7 @@ parser SwitchIngressParser(
         ig_md.iat = 0;
         ig_md.rtt = 0;
         ig_md.vxlan = 0;
+        ig_md.tg_mode = 0;
         tofino_parser.apply(pkt, ig_intr_md);
         transition select(ig_intr_md.ingress_port) {
             68: parse_pkt_gen;