fix Issue 250 RLC AM

openair2/LAYER2/RLC/AM_v9.3.0/rlc_am_retransmit.c

@@ -206,23 +206,28 @@ boolean_t rlc_am_nack_pdu (
 void rlc_am_ack_pdu (
   const protocol_ctxt_t* const  ctxt_pP,
   rlc_am_entity_t *const rlc_pP,
-  const rlc_sn_t snP)
+  const rlc_sn_t snP,
+  boolean_t free_pdu)
 {
   mem_block_t* mb_p         = rlc_pP->tx_data_pdu_buffer[snP % RLC_AM_WINDOW_SIZE].mem_block;
   rlc_am_tx_data_pdu_management_t *tx_data_pdu_buffer = &rlc_pP->tx_data_pdu_buffer[snP % RLC_AM_WINDOW_SIZE];
 
   tx_data_pdu_buffer->flags.retransmit = 0;
 
-  if ((tx_data_pdu_buffer->flags.ack == 0) && (mb_p != NULL)) {
-    //if (mb_pP != NULL) {
+  if (mb_p != NULL) {
+    if (free_pdu) {
     free_mem_block(mb_p, __func__);
     tx_data_pdu_buffer->mem_block = NULL;
     LOG_D(RLC, PROTOCOL_RLC_AM_CTXT_FMT"[ACK-PDU] ACK PDU SN %05d previous retx_count %d \n",
           PROTOCOL_RLC_AM_CTXT_ARGS(ctxt_pP,rlc_pP),
           snP,
 		  tx_data_pdu_buffer->retx_count);
+    }
 
     if (tx_data_pdu_buffer->retx_payload_size) {
+    	AssertFatal (tx_data_pdu_buffer->flags.ack == 0,
+    			"RLC AM Rx Status Report sn=%d acked twice but is pending for Retx vtA=%d vtS=%d LcId=%d\n",
+				snP, rlc_pP->vt_a,rlc_pP->vt_s,rlc_pP->channel_id);
       rlc_pP->retrans_num_bytes_to_retransmit -= tx_data_pdu_buffer->retx_payload_size;
       tx_data_pdu_buffer->retx_payload_size = 0;
       tx_data_pdu_buffer->num_holes = 0;

openair2/LAYER2/RLC/AM_v9.3.0/rlc_am_retransmit.h

@@ -74,12 +74,14 @@ protected_rlc_am_retransmit(boolean_t         rlc_am_nack_pdu (
 * \param[in]  ctxtP        Running context.
 * \param[in]  rlcP         RLC AM protocol instance pointer.
 * \param[in]  snP          Sequence number of the PDU that is acknowledged.
+* \param[in]  free_pdu     Boolean indicating that the PDU can be freed because smaller than new vtA.
 * \note                    Depending on the state of the retransmission buffer, positive confirmation can be sent to higher layers about the receiving by the peer RLC AM instance of a particular SDU.
 */
 protected_rlc_am_retransmit(void         rlc_am_ack_pdu (
                               const protocol_ctxt_t* const  ctxt_pP,
                               rlc_am_entity_t *const rlcP,
-                              const rlc_sn_t snP);)
+                              const rlc_sn_t snP,
+							  boolean_t free_pdu);)
 
 /*! \fn mem_block_t* rlc_am_retransmit_get_copy (const protocol_ctxt_t* const  ctxt_pP, rlc_am_entity_t *rlcP, rlc_sn_t snP)
 * \brief      The RLC AM PDU which have the sequence number snP is marked ACKed.

openair2/LAYER2/RLC/AM_v9.3.0/rlc_am_status_report.c

@@ -318,7 +318,7 @@ rlc_am_receive_process_control_pdu(
     {
       if (rlc_pP->control_pdu_info.num_nack == 0) {
         while (sn_cursor != ack_sn) {
-          rlc_am_ack_pdu(ctxt_pP, rlc_pP, sn_cursor);
+          rlc_am_ack_pdu(ctxt_pP, rlc_pP, sn_cursor,TRUE);
           sn_cursor = RLC_AM_NEXT_SN(sn_cursor);
         }
 
@@ -330,7 +330,7 @@ rlc_am_receive_process_control_pdu(
         prev_nack_sn = 0x3FFF;
 
         while (sn_cursor != nack_sn) {
-            rlc_am_ack_pdu(ctxt_pP, rlc_pP, sn_cursor);
+            rlc_am_ack_pdu(ctxt_pP, rlc_pP, sn_cursor,TRUE);
             sn_cursor = RLC_AM_NEXT_SN(sn_cursor);
         }
 
@@ -354,7 +354,8 @@ rlc_am_receive_process_control_pdu(
           if (sn_cursor != nack_sn) {
             rlc_am_ack_pdu(ctxt_pP,
                            rlc_pP,
-                           sn_cursor);
+                           sn_cursor,
+						   FALSE);
           } else {
         	status = rlc_am_nack_pdu (ctxt_pP,
                              rlc_pP,

openair2/LAYER2/RLC/AM_v9.3.0/rlc_am_timer_poll_retransmit.c

@@ -88,8 +88,8 @@ rlc_am_check_timer_poll_retransmit(
           /* Look for the first retransmittable PDU starting from vtS - 1 */
 		  while (sn != sn_end) {
 			tx_data_pdu_buffer_p = &rlc_pP->tx_data_pdu_buffer[sn % RLC_AM_WINDOW_SIZE];
-			AssertFatal (tx_data_pdu_buffer_p->mem_block != NULL, "RLC AM Tpoll Retx expiry sn=%d is empty vtA=%d vtS=%d LcId=%d\n",
-					sn, rlc_pP->vt_a,rlc_pP->vt_s,rlc_pP->channel_id);
+			AssertFatal (tx_data_pdu_buffer_p->mem_block != NULL, "RLC AM Tpoll Retx expiry sn=%d ack=%d is empty vtA=%d vtS=%d LcId=%d\n",
+					sn, tx_data_pdu_buffer_p->flags.ack,rlc_pP->vt_a,rlc_pP->vt_s,rlc_pP->channel_id);
 		    if ((tx_data_pdu_buffer_p->flags.ack == 0) && (tx_data_pdu_buffer_p->flags.max_retransmit == 0)) {
 		    	tx_data_pdu_buffer_p->flags.retransmit = 1;
 		    	tx_data_pdu_buffer_p->retx_payload_size = tx_data_pdu_buffer_p->payload_size;