Add comments.

openair2/LAYER2/MAC/ue_procedures.c

@@ -2563,6 +2563,10 @@ ue_scheduler(const module_id_t module_idP,
     //Rrc_xface->Frame_index=Mac_rlc_xface->frameP;
     //if (subframe%5 == 0)
     //LG#ifdef EXMIMO
+
+    // data to/from NETLINK is treated in pdcp_run.
+    // one socket is used in multiple UE's L2 FAPI simulator and
+    // only first UE need to do this.
     if(module_idP == 0){
       pdcp_run(&ctxt);
     }

targets/RT/USER/lte-enb.c

@@ -1002,7 +1002,7 @@ void init_eNB_proc(int inst) {
       pthread_create( &proc_rxtx[0].pthread_rxtx, attr0, eNB_thread_rxtx, proc );
       pthread_create( &proc_rxtx[1].pthread_rxtx, attr1, tx_thread, proc);
     }
-    else if (nfapi_mode == 2) {
+    else if (nfapi_mode == 2) { // this is neccesary in VNF or L2 FAPI simulator.
       pthread_create( &proc_rxtx[0].pthread_rxtx, attr0, eNB_thread_rxtx, &proc_rxtx[0] );
       pthread_create( &proc_rxtx[1].pthread_rxtx, attr1, eNB_thread_rxtx, &proc_rxtx[1] );
     }