rlcmac: Avoid re-arming T3182 in TBF Acknowledged mode

Re-arming upon retransmission of block CV=0 is only described in the
unacknowledged mode of operation.

Change-Id: I532def7f87367b446b5370daf8c81f511e26eb5f

2 files changed, 14 insertions, 12 deletions

diff --git a/src/rlcmac/tbf_ul_fsm.c b/src/rlcmac/tbf_ul_fsm.c
index e5a2f9a..43cb02f 100644
--- a/src/rlcmac/tbf_ul_fsm.c
+++ b/src/rlcmac/tbf_ul_fsm.c
@@ -88,9 +88,13 @@ static void reinit_pkt_acces_procedure(struct gprs_rlcmac_tbf_ul_fsm_ctx *ctx)
 		gprs_rlcmac_ul_tbf_free(ctx->ul_tbf);
 }
 
-/* 9.3.3.3.2: Upon each retransmission of the last block with CV=0, the mobile station shall restart timer T3182 for the TBF.
-* Slight impl deviation from spec: If tbf is still in contention resolution, keep using T3166, otherwise start T3182
-*/
+/* 9.3.2.4.2 (acknowledged mode): When the mobile station has sent the RLC data
+ * block with CV = 0 and there are no elements in the V(B) array set to the value
+ * Nacked, it shall start timer T3182 for this TBF.
+ * 9.3.3.3.2 (unacknowledged mode): Upon each retransmission of the last block
+ * with CV=0, the mobile station shall restart timer T3182 for the TBF.
+ * Slight impl deviation from spec: If tbf is still in contention resolution, keep using T3166, otherwise start T3182
+ */
 static void arm_T3182_if_needed(struct gprs_rlcmac_tbf_ul_fsm_ctx *ctx)
 {
 	struct osmo_fsm_inst *fi = ctx->fi;
@@ -102,10 +106,13 @@ static void arm_T3182_if_needed(struct gprs_rlcmac_tbf_ul_fsm_ctx *ctx)
 	} else {
 		OSMO_ASSERT(!osmo_timer_pending(&fi->timer) ||
 			    (osmo_timer_pending(&fi->timer) && fi->T == 3182));
-		LOGPFSML(ctx->fi, LOGL_INFO, "Last UL block sent (CV=0), start T3182\n");
-		fi->T = 3182;
-		val_sec = osmo_tdef_get(g_rlcmac_ctx->T_defs, fi->T, OSMO_TDEF_S, -1);
-		osmo_timer_schedule(&fi->timer, val_sec, 0);
+		/* TODO: once unacked mode is supported: || unacked_mode(ctx->ul_tbf) */
+		if (!osmo_timer_pending(&fi->timer)) {
+			LOGPFSML(ctx->fi, LOGL_INFO, "Last UL block sent (CV=0), start T3182\n");
+			fi->T = 3182;
+			val_sec = osmo_tdef_get(g_rlcmac_ctx->T_defs, fi->T, OSMO_TDEF_S, -1);
+			osmo_timer_schedule(&fi->timer, val_sec, 0);
+		}
 	}
 }
 
diff --git a/tests/rlcmac/rlcmac_prim_test.err b/tests/rlcmac/rlcmac_prim_test.err
index 19b289f..9435c04 100644
--- a/tests/rlcmac/rlcmac_prim_test.err
+++ b/tests/rlcmac/rlcmac_prim_test.err
@@ -599,7 +599,6 @@ DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) Copying data unit 0 (BSN=1 CV=0)
 DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) msg block (BSN 1, CS-2): 00 00 02 1d 11 e5 10 00 e2 18 f2 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 00 
 DLGLOBAL INFO UL_TBF{FINISHED}: Received Event LAST_UL_DATA_SENT
 DLGLOBAL INFO UL_TBF{FINISHED}: Data block with CV=0 retransmit attempts=1
-DLGLOBAL INFO UL_TBF{FINISHED}: Last UL block sent (CV=0), start T3182
 DLGLOBAL DEBUG Tx to lower layers: L1CTL-PDCH_DATA.request
 DLGLOBAL DEBUG Rx from lower layers: L1CTL-PDCH_RTS.indication
 DLGLOBAL DEBUG Rx RTS.ind (fn=17, ts=7, usf=0)
@@ -611,7 +610,6 @@ DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) Copying data unit 0 (BSN=1 CV=0)
 DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) msg block (BSN 1, CS-2): 00 00 02 1d 11 e5 10 00 e2 18 f2 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 00 
 DLGLOBAL INFO UL_TBF{FINISHED}: Received Event LAST_UL_DATA_SENT
 DLGLOBAL INFO UL_TBF{FINISHED}: Data block with CV=0 retransmit attempts=2
-DLGLOBAL INFO UL_TBF{FINISHED}: Last UL block sent (CV=0), start T3182
 DLGLOBAL DEBUG Tx to lower layers: L1CTL-PDCH_DATA.request
 DLGLOBAL DEBUG Rx from lower layers: L1CTL-PDCH_RTS.indication
 DLGLOBAL DEBUG Rx RTS.ind (fn=21, ts=7, usf=0)
@@ -623,7 +621,6 @@ DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) Copying data unit 0 (BSN=1 CV=0)
 DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) msg block (BSN 1, CS-2): 00 00 02 1d 11 e5 10 00 e2 18 f2 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 00 
 DLGLOBAL INFO UL_TBF{FINISHED}: Received Event LAST_UL_DATA_SENT
 DLGLOBAL INFO UL_TBF{FINISHED}: Data block with CV=0 retransmit attempts=3
-DLGLOBAL INFO UL_TBF{FINISHED}: Last UL block sent (CV=0), start T3182
 DLGLOBAL DEBUG Tx to lower layers: L1CTL-PDCH_DATA.request
 DLGLOBAL DEBUG Rx from lower layers: L1CTL-PDCH_RTS.indication
 DLGLOBAL DEBUG Rx RTS.ind (fn=26, ts=7, usf=0)
@@ -635,7 +632,6 @@ DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) Copying data unit 0 (BSN=1 CV=0)
 DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) msg block (BSN 1, CS-2): 00 00 02 1d 11 e5 10 00 e2 18 f2 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 00 
 DLGLOBAL INFO UL_TBF{FINISHED}: Received Event LAST_UL_DATA_SENT
 DLGLOBAL INFO UL_TBF{FINISHED}: Data block with CV=0 retransmit attempts=4
-DLGLOBAL INFO UL_TBF{FINISHED}: Last UL block sent (CV=0), start T3182
 DLGLOBAL DEBUG Tx to lower layers: L1CTL-PDCH_DATA.request
 DLGLOBAL DEBUG Rx from lower layers: L1CTL-PDCH_RTS.indication
 DLGLOBAL DEBUG Rx RTS.ind (fn=30, ts=7, usf=0)
@@ -647,7 +643,6 @@ DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) Copying data unit 0 (BSN=1 CV=0)
 DLGLOBAL DEBUG TBF(UL:NR-0:TLLI-00002342) msg block (BSN 1, CS-2): 00 00 02 1d 11 e5 10 00 e2 18 f2 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 2b 00 
 DLGLOBAL INFO UL_TBF{FINISHED}: Received Event LAST_UL_DATA_SENT
 DLGLOBAL INFO UL_TBF{FINISHED}: Data block with CV=0 retransmit attempts=5
-DLGLOBAL INFO UL_TBF{FINISHED}: Last UL block sent (CV=0), start T3182
 DLGLOBAL DEBUG Tx to lower layers: L1CTL-PDCH_DATA.request
 DLGLOBAL INFO UL_TBF{FINISHED}: Timeout of T3182
 DLGLOBAL INFO UL_TBF_ASS{IDLE}: Deallocated