For sflow feature, SAI changes needed for sonic-vs platform

vslib/inc/sai_vs_state.h

@@ -253,11 +253,34 @@ class SwitchState
         return it->second;
     }
 
+    void setTapNameToPortId(
+            _In_ const std::string& tapname,
+            _In_ sai_object_id_t port_id)
+    {
+        SWSS_LOG_ENTER();
+
+        m_port_id_to_tapname[port_id] = tapname;
+    }
+
+    bool  getTapNameFromPortId(
+            _In_ const sai_object_id_t port_id,
+            _Out_ std::string& if_name)
+    {
+        SWSS_LOG_ENTER();
+
+        if (m_port_id_to_tapname.find(port_id) != m_port_id_to_tapname.end())
+        {
+            if_name = m_port_id_to_tapname[port_id];
+            return true;
+        }
+        return false;
+    }
+
     private:
 
         sai_object_id_t m_switch_id;
 
-        std::map<std::string, sai_object_id_t> m_ifname_to_port_id;
+        std::map<sai_object_id_t, std::string> m_port_id_to_tapname;
 
         swss::SelectableEvent m_link_thread_event;
 

vslib/src/sai_vs_hostintf.cpp

@@ -1235,6 +1235,7 @@ sai_status_t vs_create_hostif_tap_interface(
 
     g_switch_state_map.at(switch_id)->setIfNameToPortId(vname, obj_id);
 
+    g_switch_state_map.at(switch_id)->setTapNameToPortId(name, obj_id);
     // TODO what about FDB entries notifications, they also should
     // be generated if new mac address will show up on the interface/arp table
 

vslib/src/sai_vs_port.cpp

@@ -39,8 +39,138 @@ sai_status_t vs_create_port(
     return SAI_STATUS_SUCCESS;
 }
 
+sai_status_t vs_set_port_attribute(
+            _In_ sai_object_id_t port_id,
+            _In_ const sai_attribute_t *attr)
+{
+    MUTEX();
+    SWSS_LOG_ENTER();
+
+    std::string cmd;
+
+    // Special handling for the sampling attribute modification
+    if (attr->id == SAI_PORT_ATTR_INGRESS_SAMPLEPACKET_ENABLE)
+    {
+        // Get the sample-packet object id
+        sai_object_id_t samplepacket_oid = attr->value.oid;
+
+        // Get the interface name from the port id
+        std::string if_name;
+
+        sai_object_id_t vs_switch_id = sai_switch_id_query(port_id);
+        if (vs_switch_id == SAI_NULL_OBJECT_ID)
+        {
+              SWSS_LOG_ERROR("vs_switch_id is null");
+              return SAI_STATUS_FAILURE;
+        }
+
+        auto it = g_switch_state_map.find(vs_switch_id);
+        if (it == g_switch_state_map.end())
+        {
+              SWSS_LOG_ERROR("No switch state found for the switch id %s",
+                 sai_serialize_object_id(vs_switch_id).c_str());
+              return SAI_STATUS_FAILURE;
+        }
+
+        auto sw = it->second;
+        if (sw == nullptr)
+        {
+              SWSS_LOG_ERROR("switch state for the switch id %s is null",
+                 sai_serialize_object_id(vs_switch_id).c_str());
+              return SAI_STATUS_FAILURE;
+        }
+
+        if (sw->getTapNameFromPortId(port_id, if_name) == false)
+        {
+              SWSS_LOG_ERROR("tap interface name corresponding to the port id %s is not found",
+                 sai_serialize_object_id(port_id).c_str());
+              return SAI_STATUS_FAILURE;
+        }
+
+        if (samplepacket_oid == SAI_NULL_OBJECT_ID)
+        {
+              //Delete the sampling session
+              cmd.assign("tc qdisc delete dev " + if_name + " handle ffff: ingress");
+              if (system(cmd.c_str()) == -1)
+              {
+                  SWSS_LOG_ERROR("unable to delete the sampling session \
+                                 for the interface %s",if_name);
+                  SWSS_LOG_ERROR("failed to apply the command: %s",cmd);
+                  return SAI_STATUS_FAILURE;
+              }
+              SWSS_LOG_INFO("successfully applied the command: %s", cmd);
+        } else {
+              //Get the sample rate from the sample object
+              sai_attribute_t samplepacket_attr;
+              samplepacket_attr.id = SAI_SAMPLEPACKET_ATTR_SAMPLE_RATE;
+
+              if (SAI_STATUS_SUCCESS == \
+                 vs_generic_get(SAI_OBJECT_TYPE_SAMPLEPACKET, samplepacket_oid, 1, &samplepacket_attr))
+              {
+                  int rate = samplepacket_attr.value.u32;
+
+                  //Set the default sample group ID
+                  std::string group("1");
+
+                  //Check if sampling is already enabled on the port
+                  sai_attribute_t port_attr;
+                  port_attr.id = SAI_PORT_ATTR_INGRESS_SAMPLEPACKET_ENABLE;
+
+                  // When the sampling parameters are updated,
+                  // a delete and add operation is performed on the sampling session.
+                  // If the sampling session is already created, it is deleted below.
+                  if ((vs_generic_get(SAI_OBJECT_TYPE_PORT, port_id, 1, &port_attr) \
+                       == SAI_STATUS_SUCCESS) && (port_attr.value.oid != SAI_NULL_OBJECT_ID))
+                  {
+                      //Sampling session is already created
+                      SWSS_LOG_INFO("sampling is already enabled on the port: %s .. Deleting it", \
+                                    sai_serialize_object_id(port_id).c_str());
+
+                      //Delete the sampling session
+                      cmd.assign("tc qdisc delete dev " + if_name + " handle ffff: ingress");
+                      if (system(cmd.c_str()) == -1){
+                         SWSS_LOG_ERROR("unable to delete the sampling session \
+                                         for the interface %s",if_name);
+                         SWSS_LOG_ERROR("failed to apply the command: %s",cmd);
+                         return SAI_STATUS_FAILURE;
+                      }
+                      SWSS_LOG_INFO("successfully applied the command: %s", cmd);
+                  }
+
+                  //Create a new sampling session
+                  cmd.assign("tc qdisc add dev " + if_name + " handle ffff: ingress");
+                  if (system(cmd.c_str()) == -1)
+                  {
+                      SWSS_LOG_ERROR("unable to create a sampling session for the interface %s", if_name);
+                      SWSS_LOG_ERROR("failed to apply the command: %s",cmd);
+                      return SAI_STATUS_FAILURE;
+                  }
+                  SWSS_LOG_INFO("successfully applied the command: %s", cmd);
+
+                  //Set the sampling rate of the port
+                  cmd.assign("tc filter add dev " + if_name + \
+                        " parent ffff: matchall action sample rate " + std::to_string(rate) + \
+                        " group " + group);
+                  if (system(cmd.c_str()) == -1)
+                  {
+                      SWSS_LOG_ERROR("unable to update the sampling rate of the interface %s",if_name);
+                      SWSS_LOG_ERROR("failed to apply the command: %s",cmd);
+                      return SAI_STATUS_FAILURE;
+                  }
+                  SWSS_LOG_INFO("successfully applied the command: %s", cmd);
+              } else {
+                  SWSS_LOG_ERROR("failed to update the port %s, unable to read the sample attr", if_name);
+                  return SAI_STATUS_FAILURE;
+              }
+        }
+        SWSS_LOG_INFO("successfully modified the sampling config of the port: %s",
+                      sai_serialize_object_id(port_id).c_str());
+    }
+
+    return meta_sai_set_oid((sai_object_type_t)SAI_OBJECT_TYPE_PORT, port_id, attr, &vs_generic_set);
+}
+
 VS_REMOVE(PORT,port);
-VS_SET(PORT,port);
 VS_GET(PORT,port);
 VS_GENERIC_QUAD(PORT_POOL,port_pool);
 VS_GENERIC_STATS(PORT,port);