pespin has submitted this change. (
https://gerrit.osmocom.org/c/osmo-pcu/+/18323 )
Change subject: tbf_ul: Fix UL ACK not sent to MS if intermediate UL block is
lost
......................................................................
tbf_ul: Fix UL ACK not sent to MS if intermediate UL block is lost
In normal conditions ACKing of UL blocks is only sent every
SEND_ACK_AFTER_FRAMES (20) frames. Which means if CV=0 is received (and
hence no more packets are received) less than 20 frames before a lost,
the PCU won't ask for a retransmission and wait there until some timer
destroys the TBF.
This issue is shown by TTCN3 test PCU_Tests.ttcn
TC_ul_intermediate_retrans.
Unit tests triggering this condition are adapted. Some similar tests are
not triggering it because BSN/CV relation being used is totally wrong
(like CV=0 being sent on a BSN with previous value than others).
Change-Id: I9b4ef7b7277efa645bdb5becf2e9f6b32c99a9b1
---
M src/tbf_ul.cpp
M src/tbf_ul.h
M tests/tbf/TbfTest.cpp
M tests/tbf/TbfTest.err
4 files changed, 25 insertions(+), 15 deletions(-)
Approvals:
laforge: Looks good to me, but someone else must approve
daniel: Looks good to me, approved
Jenkins Builder: Verified
diff --git a/src/tbf_ul.cpp b/src/tbf_ul.cpp
index 9899580..009dfcb 100644
--- a/src/tbf_ul.cpp
+++ b/src/tbf_ul.cpp
@@ -188,6 +188,9 @@
const struct gprs_rlc_data_info *rlc,
uint8_t *data, struct pcu_l1_meas *meas)
{
+ const struct gprs_rlc_data_block_info *rdbi;
+ struct gprs_rlc_data *block;
+
int8_t rssi = meas->have_rssi ? meas->rssi : 0;
const uint16_t ws = m_window.ws();
@@ -218,10 +221,8 @@
for (block_idx = 0; block_idx < rlc->num_data_blocks; block_idx++) {
int num_chunks;
uint8_t *rlc_data;
- const struct gprs_rlc_data_block_info *rdbi =
- &rlc->block_info[block_idx];
+ rdbi = &rlc->block_info[block_idx];
bool need_rlc_data = false;
- struct gprs_rlc_data *block;
LOGPTBFUL(this, LOGL_DEBUG,
"Got %s RLC data block: CV=%d, BSN=%d, SPB=%d, PI=%d,
E=%d, TI=%d, bitoffs=%d\n",
@@ -330,14 +331,13 @@
assemble_forward_llc(m_rlc.block(index));
}
- /* Check CV of last frame in buffer */
+ /* Last frame in buffer: */
+ block = m_rlc.block(m_window.mod_sns(m_window.v_r() - 1));
+ rdbi = &block->block_info;
+
+ /* Check if we already received all data TBF had to send: */
if (this->state_is(GPRS_RLCMAC_FLOW) /* still in flow state */
&& this->m_window.v_q() == this->m_window.v_r()) { /* if complete */
- struct gprs_rlc_data *block =
- m_rlc.block(m_window.mod_sns(m_window.v_r() - 1));
- const struct gprs_rlc_data_block_info *rdbi =
- &block->block_info;
-
LOGPTBFUL(this, LOGL_DEBUG,
"No gaps in received block, last block: BSN=%d
CV=%d\n",
rdbi->bsn, rdbi->cv);
@@ -351,13 +351,13 @@
/* If TLLI is included or if we received half of the window, we send
* an ack/nack */
- maybe_schedule_uplink_acknack(rlc);
+ maybe_schedule_uplink_acknack(rlc, rdbi->cv == 0);
return 0;
}
void gprs_rlcmac_ul_tbf::maybe_schedule_uplink_acknack(
- const gprs_rlc_data_info *rlc)
+ const gprs_rlc_data_info *rlc, bool countdown_finished)
{
bool require_ack = false;
bool have_ti = rlc->block_info[0].ti ||
@@ -373,10 +373,14 @@
LOGPTBFUL(this, LOGL_DEBUG,
"Scheduling Ack/Nack, because TLLI is included.\n");
}
- if (state_is(GPRS_RLCMAC_FINISHED)) {
+ if (countdown_finished) {
require_ack = true;
- LOGPTBFUL(this, LOGL_DEBUG,
- "Scheduling final Ack/Nack, because all data was
received and last block has CV==0.\n");
+ if (state_is(GPRS_RLCMAC_FLOW))
+ LOGPTBFUL(this, LOGL_DEBUG,
+ "Scheduling Ack/Nack, because some data is
missing and last block has CV==0.\n");
+ else if (state_is(GPRS_RLCMAC_FINISHED))
+ LOGPTBFUL(this, LOGL_DEBUG,
+ "Scheduling final Ack/Nack, because all data
was received and last block has CV==0.\n");
}
if ((m_rx_counter % SEND_ACK_AFTER_FRAMES) == 0) {
require_ack = true;
diff --git a/src/tbf_ul.h b/src/tbf_ul.h
index 85da4f6..c6df0cd 100644
--- a/src/tbf_ul.h
+++ b/src/tbf_ul.h
@@ -21,6 +21,8 @@
#ifdef __cplusplus
+#include <stdbool.h>
+
#include "tbf.h"
/*
* TBF instance
@@ -97,7 +99,7 @@
struct rate_ctr_group *m_ul_egprs_ctrs;
protected:
- void maybe_schedule_uplink_acknack(const gprs_rlc_data_info *rlc);
+ void maybe_schedule_uplink_acknack(const gprs_rlc_data_info *rlc, bool
countdown_finished);
/* Please note that all variables below will be reset when changing
* from WAIT RELEASE back to FLOW state (re-use of TBF).
diff --git a/tests/tbf/TbfTest.cpp b/tests/tbf/TbfTest.cpp
index 36f9ced..3f2925a 100644
--- a/tests/tbf/TbfTest.cpp
+++ b/tests/tbf/TbfTest.cpp
@@ -1459,6 +1459,7 @@
pdch = &the_bts->bts_data()->trx[trx_no].pdch[ts_no];
pdch->rcv_block(&data[0], sizeof(data), *fn, &meas);
+ ul_tbf->create_ul_ack(*fn, ts_no);
request_dl_rlc_block(ul_tbf, fn);
diff --git a/tests/tbf/TbfTest.err b/tests/tbf/TbfTest.err
index a1530c1..57787c5 100644
--- a/tests/tbf/TbfTest.err
+++ b/tests/tbf/TbfTest.err
@@ -7193,6 +7193,9 @@
TBF(TFI=0 TLLI=0xf1223344 DIR=UL STATE=FLOW EGPRS) Got MCS-4 RLC data block:
CV=0, BSN=64, SPB=0, PI=0, E=1, TI=0, bitoffs=33
TBF(TFI=0 TLLI=0xf1223344 DIR=UL STATE=FLOW EGPRS) BSN 64 storing in window
(1..192)
TBF(TFI=0 TLLI=0xf1223344 DIR=UL STATE=FLOW EGPRS) data_length=44, data=80 95
95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95
95 95 95 95 95 95 95 95 95 95 95 95 95 95 95 95
+TBF(TFI=0 TLLI=0xf1223344 DIR=UL STATE=FLOW EGPRS) Scheduling Ack/Nack,
because some data is missing and last block has CV==0.
+TBF(TFI=0 TLLI=0xf1223344 DIR=UL STATE=FLOW EGPRS) changes UL ACK state from
GPRS_RLCMAC_UL_ACK_NONE to GPRS_RLCMAC_UL_ACK_SEND_ACK
+TBF(TFI=0 TLLI=0xf1223344 DIR=UL STATE=FLOW EGPRS) changes UL ACK state from
GPRS_RLCMAC_UL_ACK_SEND_ACK to GPRS_RLCMAC_UL_ACK_NONE
Received RTS for PDCH: TRX=0 TS=7 FN=2654279 block_nr=10 scheduling USF=0 for
required uplink resource of UL TFI=0
TBF(TFI=0 TLLI=0xf1223344 DIR=DL STATE=ASSIGN EGPRS) start Packet Downlink
Assignment (PACCH)
+++++++++++++++++++++++++ TX : Packet Downlink Assignment
+++++++++++++++++++++++++
--
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Gerrit-Project: osmo-pcu
Gerrit-Branch: master
Gerrit-Change-Id: I9b4ef7b7277efa645bdb5becf2e9f6b32c99a9b1
Gerrit-Change-Number: 18323
Gerrit-PatchSet: 3
Gerrit-Owner: pespin <[email protected]>
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: Vadim Yanitskiy <[email protected]>
Gerrit-Reviewer: daniel <[email protected]>
Gerrit-Reviewer: laforge <[email protected]>
Gerrit-Reviewer: osmith <[email protected]>
Gerrit-Reviewer: pespin <[email protected]>
Gerrit-MessageType: merged
