dealloc SCH pdu in MAC instead of pdu_queue

- this is basically e9fcb10c9e
  but with the counterpart in the eNB's MAC

lib/include/srslte/common/buffer_pool.h

@@ -93,6 +93,10 @@ public:
 #endif
   }
 
+  uint32_t nof_available_pdus() {
+    return available.size();
+  }
+
   bool is_almost_empty() {
     return available.size() < capacity/20;
   }

lib/src/common/pdu_queue.cc

@@ -48,7 +48,7 @@ uint8_t* pdu_queue::request(uint32_t len)
     fprintf(stderr, "Error request buffer of invalid size %d. Max bytes %d\n", len, MAX_PDU_LEN);
     return NULL; 
   }
-  pdu_t *pdu = pool.allocate();  
+  pdu_t *pdu = pool.allocate("pdu_queue::request");
   if (!pdu) {
     if (log_h) {
       log_h->error("Not enough buffers for MAC PDU\n");      
@@ -96,11 +96,6 @@ bool pdu_queue::process_pdus()
     if (callback) {
       callback->process_pdu(pdu->ptr, pdu->len, pdu->channel, pdu->tstamp);
     }
-    if (pdu->channel == DCH) {
-      if (!pool.deallocate(pdu)) {
-        log_h->warning("Error deallocating from buffer pool in process_pdus(): buffer not created in this pool.\n");
-      }
-    }
     cnt++;
     have_data = true;
   }

srsenb/src/mac/ue.cc

@@ -152,6 +152,8 @@ void ue::process_pdu(uint8_t* pdu, uint32_t nof_bytes, srslte::pdu_queue::channe
     pcap->write_ul_crnti(pdu, nof_bytes, rnti, true, last_tti);
   }
 
+  pdus.deallocate(pdu);
+
   uint32_t lcid_most_data = 0;
   int most_data = -99;
   

srsue/src/mac/demux.cc

@@ -148,6 +148,8 @@ void demux::process_pdu(uint8_t *mac_pdu, uint32_t nof_bytes, srslte::pdu_queue:
 
       process_sch_pdu(&mac_msg);
       //srslte_vec_fprint_byte(stdout, mac_pdu, nof_bytes);
+
+      pdus.deallocate(mac_pdu);
       break;
     case srslte::pdu_queue::BCH:
       rlc->write_pdu_bcch_dlsch(mac_pdu, nof_bytes);