diff --git a/tests/alloc/AllocTest.cpp b/tests/alloc/AllocTest.cpp
index 80e8c34..830ca90 100644
--- a/tests/alloc/AllocTest.cpp
+++ b/tests/alloc/AllocTest.cpp
@@ -36,6 +36,17 @@
 void *tall_pcu_ctx;
 int16_t spoof_mnc = 0, spoof_mcc = 0;
 
+static gprs_rlcmac_tbf *tbf_alloc(struct gprs_rlcmac_bts *bts,
+		struct gprs_rlcmac_tbf *old_tbf, gprs_rlcmac_tbf_direction dir,
+		uint8_t tfi, uint8_t trx,
+		uint8_t ms_class, uint8_t single_slot)
+{
+	if (dir == GPRS_RLCMAC_UL_TBF)
+		return tbf_alloc_ul_tbf(bts, old_tbf, tfi, trx, ms_class, single_slot);
+	else
+		return tbf_alloc_dl_tbf(bts, old_tbf, tfi, trx, ms_class, single_slot);
+}
+
 static void test_alloc_a(gprs_rlcmac_tbf_direction dir, const int count)
 {
 	int tfi;
@@ -136,14 +147,14 @@
 
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 		OSMO_ASSERT(tfi >= 0);
-		ul_tbf = tbf_alloc(bts, NULL, GPRS_RLCMAC_UL_TBF, tfi, trx_no, ms_class, 1);
+		ul_tbf = tbf_alloc_ul_tbf(bts, NULL, tfi, trx_no, ms_class, 1);
 		OSMO_ASSERT(ul_tbf);
 		dump_assignment(ul_tbf, "UL");
 
 		/* assume final ack has not been sent */
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 		OSMO_ASSERT(tfi >= 0);
-		dl_tbf = tbf_alloc(bts, ul_tbf, GPRS_RLCMAC_DL_TBF, tfi, trx_no, ms_class, 0);
+		dl_tbf = tbf_alloc_dl_tbf(bts, ul_tbf, tfi, trx_no, ms_class, 0);
 		OSMO_ASSERT(dl_tbf);
 		dump_assignment(dl_tbf, "DL");
 
@@ -177,7 +188,7 @@
 
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 		OSMO_ASSERT(tfi >= 0);
-		dl_tbf = tbf_alloc(bts, NULL, GPRS_RLCMAC_DL_TBF, tfi, trx_no, ms_class, 1);
+		dl_tbf = tbf_alloc_dl_tbf(bts, NULL, tfi, trx_no, ms_class, 1);
 		dl_tbf->m_tlli = 0x23;
 		dl_tbf->m_tlli_valid = true;
 		OSMO_ASSERT(dl_tbf);
@@ -185,7 +196,7 @@
 
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 		OSMO_ASSERT(tfi >= 0);
-		ul_tbf = tbf_alloc(bts, dl_tbf, GPRS_RLCMAC_UL_TBF, tfi, trx_no, ms_class, 0);
+		ul_tbf = tbf_alloc_ul_tbf(bts, dl_tbf, tfi, trx_no, ms_class, 0);
 		ul_tbf->m_tlli = 0x23;
 		ul_tbf->m_tlli_valid = true;
 		ul_tbf->dir.ul.contention_resolution_done = 1;
@@ -226,14 +237,14 @@
 
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 		OSMO_ASSERT(tfi >= 0);
-		ul_tbf = tbf_alloc(bts, NULL, GPRS_RLCMAC_UL_TBF, tfi, trx_no, ms_class, 0);
+		ul_tbf = tbf_alloc_ul_tbf(bts, NULL, tfi, trx_no, ms_class, 0);
 		OSMO_ASSERT(ul_tbf);
 		dump_assignment(ul_tbf, "UL");
 
 		/* assume final ack has not been sent */
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 		OSMO_ASSERT(tfi >= 0);
-		dl_tbf = tbf_alloc(bts, ul_tbf, GPRS_RLCMAC_DL_TBF, tfi, trx_no, ms_class, 0);
+		dl_tbf = tbf_alloc_dl_tbf(bts, ul_tbf, tfi, trx_no, ms_class, 0);
 		OSMO_ASSERT(dl_tbf);
 		dump_assignment(dl_tbf, "DL");
 
@@ -290,13 +301,13 @@
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 
 		OSMO_ASSERT(tfi >= 0);
-		ul_tbf = tbf_alloc(bts, NULL, GPRS_RLCMAC_UL_TBF, tfi, trx_no, ms_class, 1);
+		ul_tbf = tbf_alloc_ul_tbf(bts, NULL, tfi, trx_no, ms_class, 1);
 		OSMO_ASSERT(ul_tbf);
 
 		/* assume final ack has not been sent */
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 		OSMO_ASSERT(tfi >= 0);
-		dl_tbf = tbf_alloc(bts, ul_tbf, GPRS_RLCMAC_DL_TBF, tfi, trx_no, ms_class, 0);
+		dl_tbf = tbf_alloc_dl_tbf(bts, ul_tbf, tfi, trx_no, ms_class, 0);
 		OSMO_ASSERT(dl_tbf);
 
 		/* verify that both are on the same ts */
@@ -333,14 +344,14 @@
 
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 		OSMO_ASSERT(tfi >= 0);
-		dl_tbf = tbf_alloc(bts, NULL, GPRS_RLCMAC_DL_TBF, tfi, trx_no, ms_class, 1);
+		dl_tbf = tbf_alloc_dl_tbf(bts, NULL, tfi, trx_no, ms_class, 1);
 		OSMO_ASSERT(dl_tbf);
 		dl_tbf->m_tlli = 0x23;
 		dl_tbf->m_tlli_valid = true;
 
 		tfi = the_bts.tfi_find_free(GPRS_RLCMAC_UL_TBF, &trx_no, -1);
 		OSMO_ASSERT(tfi >= 0);
-		ul_tbf = tbf_alloc(bts, dl_tbf, GPRS_RLCMAC_UL_TBF, tfi, trx_no, ms_class, 0);
+		ul_tbf = tbf_alloc_ul_tbf(bts, dl_tbf, tfi, trx_no, ms_class, 0);
 		OSMO_ASSERT(ul_tbf);
 		ul_tbf->m_tlli = 0x23;
 		ul_tbf->m_tlli_valid = true;